WorldWideScience

Sample records for rocket site antelope

  1. Streamlined Approach for Environmental Restoration Plan for Corrective Action Unit 496: Buried Rocket Site, Antelope Lake, Tonopah Test Range

    Energy Technology Data Exchange (ETDEWEB)

    U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office; Bechtel Nevada

    2004-05-01

    This Streamlined Approach for Environmental Restoration (SAFER) plan details the activities necessary to close Corrective Action Unit 496: Buried Rocket Site, Antelope Lake. CAU 496 consists of one site located at the Tonopah Test Range, Nevada.

  2. Closure Letter Report for Corrective Action Unit 496: Buried Rocket Site - Antelope Lake

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environmental Restoration

    2007-05-01

    A Streamlined Approach for Environmental Restoration (SAFER) Plan for investigation and closure of CAU 496, Corrective Action Site (CAS) TA-55-008-TAAL (Buried Rocket), at the Tonopah Test Range (TTR), was approved by the Nevada Department of Environmental Protection (NDEP) on July 21,2004. Approval to transfer CAS TA-55-008-TAAL from CAU 496 to CAU 4000 (No Further Action Sites) was approved by NDEP on December 21, 2005, based on the assumption that the rocket did not present any environmental concern. The approval letter included the following condition: ''NDEP understands, from the NNSA/NSO letter dated November 30,2005, that a search will be conducted for the rocket during the planned characterization of other sites at the Tonopah Test Range and, if found, the rocket will be removed as a housekeeping measure''. NDEP and U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office personnel located the rocket on Mid Lake during a site visit to TTR, and a request to transfer CAS TA-55-008-TAAL from CAU 4000 back to CAU 496 was approved by NDEP on September 11,2006. CAS TA-55-008-TAAL was added to the ''Federal Facility Agreement and Consent Order'' of 1996, based on an interview with a retired TTR worker in 1993. The original interview documented that a rocket was launched from Area 9 to Antelope Lake and was never recovered due to the high frequency of rocket tests being conducted during this timeframe. The interviewee recalled the rocket being an M-55 or N-55 (the M-50 ''Honest John'' rocket was used extensively at TTR from the 1960s to early 1980s). A review of previously conducted interviews with former TTR personnel indicated that the interviewees confused information from several sites. The location of the CAU 496 rocket on Mid Lake is directly south of the TTR rocket launch facility in Area 9 and is consistent with information gathered on the lost rocket during recent

  3. Rocket

    Directory of Open Access Journals (Sweden)

    K. Karmarkar

    1952-09-01

    Full Text Available The rockets of World War II represented, not the invention of a new weapon, but the modernization of a very old one. As early as 1232 A.D, the Chinese launched rockets against the Mongols. About a hundred years later the knowledge of ledge of rockets was quite widespread and they were used to set fire to buildings and to terrorize the enemy. But as cannon developed, rockets declined in warfare. However rockets were used occasionally as weapons till about 1530 A.D. About this time improvements in artillery-rifled gun barrel and mechanism to absorb recoil-established a standard of efficiency with which rockets could not compare until World War II brought pew conditions

  4. Aquifer-System Compaction and Land Subsidence: Measurements, Analyses, and Simulations-the Holly Site, Edwards Air Force Base, Antelope Valley, California

    Science.gov (United States)

    Sneed, Michelle; Galloway, Devin L.

    2000-01-01

    Land subsidence resulting from ground-water-level declines has long been recognized as a problem in Antelope Valley, California. At Edwards Air Force Base (EAFB), ground-water extractions have caused more than 150 feet of water-level decline, resulting in nearly 4 feet of subsidence. Differential land subsidence has caused sinklike depressions and earth fissures and has accelerated erosion of the playa lakebed surface of Rogers Lake at EAFB, adversely affecting the runways on the lakebed which are used for landing aircraft such as the space shuttles. Since 1990, about 0.4 foot of aquifer-system compaction has been measured at a deep (840 feet) borehole extensometer (Holly site) at EAFB. More than 7 years of paired ground-water-level and aquifer-system compaction measurements made at the Holly site were analyzed for this study. Annually, seasonal water-level fluctuations correspond to steplike variations in aquifer-system compaction; summer water-level drawdowns are associated with larger rates of compaction, and winter water-level recoveries are associated with smaller rates of compaction. The absence of aquifer-system expansion during recovery is consistent with the delayed drainage and resultant delayed, or residual, compaction of thick aquitards. A numerical one-dimensional MODFLOW model of aquitard drainage was used to refine estimates of aquifer-system hydraulic parameters that control compaction and to predict potential future compaction at the Holly site. The analyses and simulations of aquifer-system compaction are based on established theories of aquitard drainage. Historical ground-water-level and land-subsidence data collected near the Holly site were used to constrain simulations of aquifer-system compaction and land subsidence at the site for the period 1908?90, and ground-water-level and aquifer- system compaction measurements collected at the Holly site were used to constrain the model for the period 1990?97. Model results indicate that two thick

  5. Radiological effluents released from nuclear rocket and ramjet engine tests at the Nevada Test Site 1959 through 1969: Fact Book

    Energy Technology Data Exchange (ETDEWEB)

    Friesen, H.N.

    1995-06-01

    Nuclear rocket and ramjet engine tests were conducted on the Nevada Test Site (NTS) in Area 25 and Area 26, about 80 miles northwest of Las Vegas, Nevada, from July 1959 through September 1969. This document presents a brief history of the nuclear rocket engine tests, information on the off-site radiological monitoring, and descriptions of the tests.

  6. Draft genome sequence of the Tibetan antelope

    OpenAIRE

    Ge, Ri-Li; Cai, Qingle; Shen, Yong-Yi; San, A.; Ma, Lan; Zhang, Yong; Yi, Xin; Chen, Yan; Yang, Lingfeng; Huang, Ying; He, Rongjun; Hui, Yuanyuan; Hao, Meirong; Li, Yue; Wang, Bo

    2013-01-01

    The Tibetan antelope (Pantholops hodgsonii) is endemic to the extremely inhospitable high-altitude environment of the Qinghai-Tibetan Plateau, a region that has a low partial pressure of oxygen and high ultraviolet radiation. Here we generate a draft genome of this artiodactyl and use it to detect the potential genetic bases of highland adaptation. Compared with other plain-dwelling mammals, the genome of the Tibetan antelope shows signals of adaptive evolution and gene-family expansion in ge...

  7. Running a seismic data center with Antelope at ZAMG

    Science.gov (United States)

    Horn, Nikolaus

    2010-05-01

    Beeing one one of the first customers of the commercial data acquisition system Antelope, ZAMG has now over 10 years of experience running a medium size data center with the commercial software package Antelope from BRTT. We outline the configuration of the data center facilities, and describe a few application that have been designed based on the Antelope toolbox for software development. Since ZAMG hosts the Austrian NDC, we present the usage of the Antelope software in that framework.

  8. Draft genome sequence of the Tibetan antelope.

    Science.gov (United States)

    Ge, Ri-Li; Cai, Qingle; Shen, Yong-Yi; San, A; Ma, Lan; Zhang, Yong; Yi, Xin; Chen, Yan; Yang, Lingfeng; Huang, Ying; He, Rongjun; Hui, Yuanyuan; Hao, Meirong; Li, Yue; Wang, Bo; Ou, Xiaohua; Xu, Jiaohui; Zhang, Yongfen; Wu, Kui; Geng, Chunyu; Zhou, Weiping; Zhou, Taicheng; Irwin, David M; Yang, Yingzhong; Ying, Liu; Bao, Haihua; Kim, Jaebum; Larkin, Denis M; Ma, Jian; Lewin, Harris A; Xing, Jinchuan; Platt, Roy N; Ray, David A; Auvil, Loretta; Capitanu, Boris; Zhang, Xiufeng; Zhang, Guojie; Murphy, Robert W; Wang, Jun; Zhang, Ya-Ping; Wang, Jian

    2013-01-01

    The Tibetan antelope (Pantholops hodgsonii) is endemic to the extremely inhospitable high-altitude environment of the Qinghai-Tibetan Plateau, a region that has a low partial pressure of oxygen and high ultraviolet radiation. Here we generate a draft genome of this artiodactyl and use it to detect the potential genetic bases of highland adaptation. Compared with other plain-dwelling mammals, the genome of the Tibetan antelope shows signals of adaptive evolution and gene-family expansion in genes associated with energy metabolism and oxygen transmission. Both the highland American pika, and the Tibetan antelope have signals of positive selection for genes involved in DNA repair and the production of ATPase. Genes associated with hypoxia seem to have experienced convergent evolution. Thus, our study suggests that common genetic mechanisms might have been utilized to enable high-altitude adaptation.

  9. Drowsy Cheetah Hunting Antelopes: A Diffusing Predator Seeking Fleeing Prey

    OpenAIRE

    Winkler, Karen; Bray, Alan J.

    2004-01-01

    We consider a system of three random walkers (a `cheetah' surrounded by two `antelopes') diffusing in one dimension. The cheetah and the antelopes diffuse, but the antelopes experience in addition a deterministic relative drift velocity, away from the cheetah, proportional to their distance from the cheetah, such that they tend to move away from the cheetah with increasing time. Using the backward Fokker-Planck equation we calculate, as a function of their initial separations, the probability...

  10. Drowsy Cheetah Hunting Antelopes: A Diffusing Predator Seeking Fleeing Prey

    OpenAIRE

    Winkler, Karen; Bray, Alan J.

    2004-01-01

    We consider a system of three random walkers (a `cheetah' surrounded by two `antelopes') diffusing in one dimension. The cheetah and the antelopes diffuse, but the antelopes experience in addition a deterministic relative drift velocity, away from the cheetah, proportional to their distance from the cheetah, such that they tend to move away from the cheetah with increasing time. Using the backward Fokker-Planck equation we calculate, as a function of their initial separations, the probability...

  11. Drowsy cheetah hunting antelopes: a diffusing predator seeking fleeing prey

    Science.gov (United States)

    Winkler, Karen; Bray, Alan J.

    2005-02-01

    We consider a system of three random walkers (a 'cheetah' surrounded by two 'antelopes') diffusing in one dimension. The cheetah and the antelopes diffuse, but the antelopes experience in addition a deterministic relative drift velocity, away from the cheetah, proportional to their distance from the cheetah, such that they tend to move away from the cheetah with increasing time. Using the backward Fokker-Planck equation we calculate, as a function of their initial separations, the probability that the cheetah has caught neither antelope after infinite time.

  12. Running energetics in the pronghorn antelope.

    Science.gov (United States)

    Lindstedt, S L; Hokanson, J F; Wells, D J; Swain, S D; Hoppeler, H; Navarro, V

    1991-10-24

    The pronghorn antelope (Antilocapra americana) has an alleged top speed of 100 km h-1, second only to the cheetah (Acionyx jubatus) among land vertebrates, a possible response to predation in the exposed habitat of the North American prairie. Unlike cheetahs, however, pronghorn antelope are distance runners rather than sprinters, and can run 11 km in 10 min, an average speed of 65 km h-1. We measured maximum oxygen uptake in pronghorn antelope to distinguish between two potential explanations for this ability: either they have evolved a uniquely high muscular efficiency (low cost of transport) or they can supply oxygen to the muscles at unusually high levels. Because the cost of transport (energy per unit distance covered per unit body mass) varies as a predictable function of body mass among terrestrial vertebrates, we can calculate the predicted cost to maintain speeds of 65 and 100 km h-1 in an average 32-kg animal. The resulting range of predicted values, 3.2-5.1 ml O2 kg-1 s-1, far surpasses the predicted maximum aerobic capacity of a 32-kg mammal (1.5 ml O2 kg-1 s-1). We conclude that their performance is achieved by an extraordinary capacity to consume and process enough oxygen to support a predicted running speed greater than 20 ms-1 (70 km h-1), attained without unique respiratory-system structures.

  13. 78 FR 45114 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2013-07-26

    ... proposing to approve revisions to the Antelope Valley Air Quality Management District (AVAQMD) portion of... Rule 431.1 was actually for the South Coast Air Quality Management District (SCAQMD). The Antelope... Antelope Valley amended or rescinded the rule. On January 1, 2002, Antelope Valley Air Quality...

  14. Rocket Flight.

    Science.gov (United States)

    Van Evera, Bill; Sterling, Donna R.

    2002-01-01

    Describes an activity for designing, building, and launching rockets that provides students with an intrinsically motivating and real-life application of what could have been classroom-only concepts. Includes rocket design guidelines and a sample grading rubric. (KHR)

  15. 78 FR 59840 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2013-09-30

    ... of plan. * * * * * (c) * * * (428) * * * (i) * * * (B) Antelope Valley Air Quality Management...) * * * (i) * * * (B) Antelope Valley Air Quality Management District. (1) Rule 431.1, ``Sulfur Content of... AGENCY 40 CFR Part 52 Revisions to the California State Implementation Plan, Antelope Valley Air...

  16. 77 FR 2469 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2012-01-18

    ... to the Antelope Valley Air Quality Management District (AVAQMD) and Imperial County Air Pollution.... * * * * * (G) Antelope Valley Air Quality Management District. (1) Rule 1134, ``Stationary Gas Turbines... AGENCY 40 CFR Part 52 Revisions to the California State Implementation Plan, Antelope Valley Air Quality...

  17. Superfund record of decision (EPA Region 2): Malta Rocket Fuel Area Site, Towns of Malta and Stillwater, Saratoga County, NY, July 13, 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    This Record of Decision (ROD) documents the U.S. Environmental Protection Agency`s (EPA`s) selection of the remedial action for the Malta Rocket Fuel Area site (the Site). The remedy addresses the principal threats to human health and the environment that are posed by conditions at the Site. Exposure to soil contamination at the Malta Test Station will be addressed by excavation and off-site disposal of the contaminated soil. Ingestion of contaminated ground water by on-site employees will be addressed by pumping the Test Station water supply wells and treating the water to acceptable drinking water standards using an air stripper. Ground water not captured by the air stripper will be remediated to cleanup standards through natural attenuation and degradation processes.

  18. The species of the Antelope-genus Pediotragus

    NARCIS (Netherlands)

    Jentink, F.A.

    1900-01-01

    A skin of a male antelope, collected by Mr. A. Sharpe in Southern Angoniland has been described by Mr. Oldfield Thomas under a new specific title, Rhaphiceros Sharpei (P. Z. S. L. 1896, p. 796, plate XXXIX); the author had no cranial evidence of its age, as the skull of the individual was wanting.

  19. Implementation of a new picking procedure in the Antelope software

    Science.gov (United States)

    Tiberi, Lara; Costa, Giovanni; Spallarossa, Daniele

    2014-05-01

    Automatic estimates of earthquake parameters continues to be of considerable interest to the seismological community. In this study we present a new automatic procedure for a quasi real-time location of events. This procedure is a combination of the solid and tested Antelope sotfware with a new picking procedure, the AutoPicker (DipTeRiS, University of Genova). Antelope picking procedure consists on: a) Prefiltering into different frequency pass bands; b) Run STA/LTA detectors in one or more channels of the waveform data; c) Associate event locations by searching over one or more spatial grids for a candidate hypocenter that produces theoretical time moveout (P and S) to each station that most closely matches the observations. The main characteristics of the AutoPicker picking algorithm are: a) Pre-filtering and envelope calculation to prearrange the onset; b) Preliminary detection of P onset using the AIC based picker; c) P validation, Signal Variance/Noise Variance analysis sample by sample; d) Preliminary earthquake location; e) Detection of S onset adopting the AIC based picker; f) S/N analysis, S validation; g) Earthquake location. We have applied these two automatic procedures to the Emilia sequence occurred in May-June 2012. In this comparison the distribution of the differences between the manual and the two automatic P-onset are comparable. The average values of P differences are similar, but we have to point out that the AutoPicker procedure gives a st.deviation value lower than the Antelope ones and most important it picks the 16% of phases more than the other algoritm. For S-phases the AutoPicker algorithm picks 178 phases with a mean value of 0.09 sec, instead of the 16s of Antelope with a mean value of 3.75 sec. For more than 90% events the epicentral differences of AutoPicker is less than 5 kms, instead of the Antelope differences which are less than 10 kms. For the depth differences the mean values and the distributions of the two procedures are

  20. Visitor center at the Antelope Valley California Poppy Reserve, Lancaster, California

    Energy Technology Data Exchange (ETDEWEB)

    Colyer, R.D.; Freeman, S.P.

    1981-01-01

    The Antelope Valley California Poppy Reserve contains the largest remaining stand of the California Poppy (Eschschozia Californica), the state flower of California. To welcome the thousands of people viewing the desert wildflowers each spring, the State of California decided to build a visitor/interpretive center. This building deals primarily with the question of fit; a building's fit aesthetically with its site and the fit of a building's design response to the climate of the site. In this case, both aspects of this question led the client and architects to seek an earth sheltered solution using materials at least metaphorically indigenous to the region. On both a technical and formal level, this building seeks to fit the unique climate and historical heritage of its site.

  1. DNA in the conservation and management of African antelope

    DEFF Research Database (Denmark)

    Lorenzen, Eline

    2016-01-01

    tool in informed species conservation and sustainable wildlife management. The movement of antelope through translocations, reintroductions, and population augmentations is common practice in wildlife management. DNA-led species identification using genetic barcoding is an effective use of genetic data......This chapter addresses species conservation using population genetics, including delimiting species and subspecies, revealing cryptic diversity, and assessing hybridization between distinct populations. The molecular information from these studies is publicly available and can be found in online...

  2. Large-Scale Land Development, Fugitive Dust, and Increased Coccidioidomycosis Incidence in the Antelope Valley of California, 1999-2014.

    Science.gov (United States)

    Colson, Aaron J; Vredenburgh, Larry; Guevara, Ramon E; Rangel, Natalia P; Kloock, Carl T; Lauer, Antje

    2017-06-01

    Ongoing large-scale land development for renewable energy projects in the Antelope Valley, located in the Western Mojave Desert, has been blamed for increased fugitive dust emissions and coccidioidomycosis incidence among the general public in recent years. Soil samples were collected at six sites that were destined for solar farm construction and were analyzed for the presence of the soil-borne fungal pathogen Coccidioides immitis which is endemic to many areas of central and southern California. We used a modified culture-independent nested PCR approach to identify the pathogen in all soil samples and also compared the sampling sites in regard to soil physical and chemical parameters, degree of disturbance, and vegetation. Our results indicated the presence of C. immitis at four of the six sites, predominantly in non-disturbed soils of the Pond-Oban complex, which are characterized by an elevated pH and salt bush communities, but also in grassland characterized by different soil parameters and covered with native and non-native annuals. Overall, we were able to detect the pathogen in 40% of the soil samples (n = 42). Incidence of coccidioidomycosis in the Antelope Valley was positively correlated with land use and particulate matter in the air (PM10) (Pearson correlation coefficient >0.5). With the predicted population growth and ongoing large-scale disturbance of soil in the Antelope Valley in coming years, incidence of coccidioidomycosis will likely further increase if policy makers and land developers continue to ignore the risk of grading land without implementing long-term dust mitigation plans in Environmental Impact Reports.

  3. 76 FR 38572 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2011-07-01

    ... taking direct final action to approve revisions to the Antelope Valley Air Quality Management District... Valley Air Quality Management District (AVAQMD) and submitted by the California Air Resources Board (CARB... AGENCY 40 CFR Part 52 Revisions to the California State Implementation Plan, Antelope Valley Air...

  4. 76 FR 38589 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2011-07-01

    ... AGENCY 40 CFR Part 52 Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management District AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule. SUMMARY: EPA is proposing to approve revisions to the Antelope Valley Air Quality Management District (AVAQMD) portion...

  5. 78 FR 49925 - Revisions to California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2013-08-16

    ... the Antelope Valley Air Quality Air Management District (AVAQMD) and Ventura County Air Pollution... AGENCY 40 CFR Part 52 Revisions to California State Implementation Plan, Antelope Valley Air Quality Management District and Ventura County Air Pollution Control District AGENCY: Environmental Protection...

  6. 77 FR 12495 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2012-03-01

    ... AGENCY 40 CFR Part 52 Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management District and Mojave Desert Quality Management District AGENCY: Environmental Protection Agency... the Antelope Valley Air Quality Management District (AVAQMD) and Mojave Desert Air Quality...

  7. Land use and water use in the Antelope Valley, California

    Science.gov (United States)

    Templin, W.E.; Phillips, S.P.; Cherry, D.E.; DeBortoli, M.L.; Haltom, T.C.; McPherson, K.R.; Mrozek, C.A.

    1995-01-01

    Urban land use and water use in the Antelope Valley, California, have increased greatly since the devel- opment of the valley began in the late 1800's. Ground water always has been a major source of supply in this area because of limited local surface-water resources. Ground-water pumpage reportedly increased from about 29,000 acre-feet in 1919 to about 400,000 acre-feet in the 1950's. Declines in ground-water levels and increased costs of electrical power in the 1970's resulted in a reduction in the quantity of ground-water pumped annually for irrigation uses. Ground-water pumpage was further reduced in the 1970's following the completion of the California Aqueduct, which conveys water from northern California. Total annual reported ground-water pumpage decreased to a low of about 53,200 acre-feet in 1983 and increased again to about 91,700 acre-feet in 1991. Rapid urban development and the 1987-92 drought renewed concern about a possible return to extensive ground-water- storage depletion and increased land subsidence. Water-demand forecasts in 1980 for the Antelope Valley indicated that total annual demand by the year 2020 was expected to be about 250,000 acre- feet per year, with agricultural uses to be about 65 percent of this total demand. In 1990, total demand. In 1993, preliminary forecasts for total demand for 2010 ranged from about 127,000 to 329,000 acre-feet with urban water uses accounting for all but a few percent of the total anticipated demand. This history of forecasts indicates that expectations change with time. Factors that affect water demand change and different forecasting methods are used. Water-conservation options may be adopted to employ best-management practices that would further influence future water demands in the Antelope Valley.

  8. Rocket Tablet,

    Science.gov (United States)

    1984-09-12

    is a vast and desolate world, this is a strip of mir- aculous land! How many struggling dramas full of power and * grandeur were cheered, resisted and...rocket officers and men, a group enormous and powerful , marched into this land soaked with the fresh blood of our ancestors. This place is about to...and tough pestering said he wanted an American aircraft ob- tained on the battlefield to transport goods from Lanzhou, Xian, Beijing, Guangzhou and

  9. In vivo and in vitro development of Tibetan antelope (Pantholops hodgsonii interspecific cloned embryos

    Directory of Open Access Journals (Sweden)

    Guanghua SU,Lei CHENG,Yu GAO,Kun LIU,Zhuying WEI,Chunling BAI,Fengxia YIN,Li GAO,Guangpeng LI,Shorgan BOU

    2014-02-01

    Full Text Available The Tibetan antelope is endemic to the Tibetan Plateau, China, and is now considered an endangered species. As a possible rescue strategy, the development of embryos constructed by interspecies somatic cell nuclear transfer (iSCNT was examined. Tibetan antelope fibroblast cells were transferred into enucleated bovine, ovine and caprine oocytes. These cloned embryos were then cultured in vitro or in the oviducts of intermediate animals. Less than 0.5% of the reconstructed antelope-bovine embryos cultured in vitro developed to the blastocyst stage. However, when the cloned antelope-bovine embryos were transferred to caprine oviducts, about 1.6% of the embryos developed to the blastocyst stage. In contrast, only 0.7% of the antelope-ovine embryos developed to the morula stage and none developed to blastocysts in ovine oviducts. The treatment of donor cells and bovine oocytes with trichostatin A did not improve the embryo development even when cultured in the oviducts of ovine and caprine. When the antelope-bovine embryos, constructed from oocytes treated with roscovitine or trichostatin A, were cultured in rabbit oviducts 2.3% and 14.3% developed to blastocysts, respectively. It is concluded that although some success was achieved with the protocols used, interspecies cloning of Tibetan antelope presents difficulties still to be overcome. The mechanisms resulting in the low embryo development need investigation and progress might require a deeper understanding of cellular reprogramming.

  10. Health evaluation of a pronghorn antelope population in Oregon

    Science.gov (United States)

    Dunbar, M.R.; Velarde, R.; Gregg, M.A.; Bray, M.

    1999-01-01

    During 1996 and 1997, the U.S. Fish and Wildlife Service conducted a study to determine the cause(s) of population decline and low survival of pronghorn antelope (Antilocapra americana) fawns on Hart Mountain National Antelope Refuge (HMNAR) located in southeastern Oregon (USA). As part of that study, blood, fecal, and tissue samples from 104 neonatal fawns, 40 adult does, and nine adult male pronghorns were collected to conduct a health evaluation of the population. Physiological parameters related to nutrition and/or disease were studied. No abnormalities were found in the complete blood cell counts of adults (n = 40) or fawns (n = 44 to 67). Serum total protein and blood urea nitrogen (BUN) levels were lower compared to other pronghorn populations. Does had mean BUN values significantly lower (P bovine rhinotracheitis (n = 18, negative), and bovine viral diarrhea (n = 18, negative). Considering the parameters examined, we found no apparent predisposing factors to mortality including those killed by coyotes, but some nutritional parameters suggest that pronghorns on HMNAR exist on a diet low in protein and Se and marginal in Cu. The effect these factors have on the population is not known.

  11. A questionnaire survey of the management and use of anthelmintics in cattle and antelope in mixed farming systems in Zimbabwe

    Directory of Open Access Journals (Sweden)

    O. Madzingira

    2002-07-01

    Full Text Available A survey of the management of mixed farming of cattle and antelope and use of anthelmintics was conducted on eleven farms between August and December 1999 by a self-administered questionnaire. Seventeen antelope species ranging from grey duikers (Sylvicapra grimmia to eland (Taurotragus oryx occurred on the farms. Impala (Aepyceros melampus was the most abundant antelope on the farms. Seventy-five per cent of the antelope species on the farms were grazers and mixed feeders and shared grazing with cattle. Most farmers (n =8 did not consider the stocking density for cattle and antelope as an important management factor. Fifty-four per cent of the farmers (n = 6 routinely dewormed both cattle and antelopes. Albendazole and fenbendazole were the most commonly used drugs for deworming cattle (72.7 % and antelope species (54.5 %. The deworming of antelope was carried out during the dry season, using albendazole-, fenbendazole-and rafoxanide-medicated supplementary feed blocks. Doramectin injections were given to antelopes on two farms. Cattle were dewormed preventively and according to the general body condition of the animal. Few farmers (n = 4 followed the recommended deworming programme for cattle in Zimbabwe and only one farmer followed a specified dosing programme for game. However, results from the survey on the deworming of game indicate that farmers perceived helminth infections in antelope to be important.

  12. Groundwater-flow and land-subsidence model of Antelope Valley, California

    Science.gov (United States)

    Siade, Adam J.; Nishikawa, Tracy; Rewis, Diane L.; Martin, Peter; Phillips, Steven P.

    2014-01-01

    Antelope Valley, California, is a topographically closed basin in the western part of the Mojave Desert, about 50 miles northeast of Los Angeles. The Antelope Valley groundwater basin is about 940 square miles and is separated from the northern part of Antelope Valley by faults and low-lying hills. Prior to 1972, groundwater provided more than 90 percent of the total water supply in the valley; since 1972, it has provided between 50 and 90 percent. Most groundwater pumping in the valley occurs in the Antelope Valley groundwater basin, which includes the rapidly growing cities of Lancaster and Palmdale. Groundwater-level declines of more than 270 feet in some parts of the groundwater basin have resulted in an increase in pumping lifts, reduced well efficiency, and land subsidence of more than 6 feet in some areas. Future urban growth and limits on the supply of imported water may increase reliance on groundwater.

  13. Antelope Valley Air Quality Management District; Approval of California Air Plan Revisions

    Science.gov (United States)

    EPA is proposing to approve and conditionally approve revisions to the Antelope Valley Air Quality Management District (AVAQMD or “District”) portion of the California State Implementation Plan (SIP).

  14. Colorado Plateau Rapid Ecoregion Assessment Conservation Elements - Terrestrial Species: Pronghorn Antelope

    Data.gov (United States)

    Bureau of Land Management, Department of the Interior — This map shows the potential current distribution of pronghorn antelope, in the context of current and near-term terrestrial intactness and long-term potential for...

  15. Preliminary study on migration pattern of the Tibetan antelope ( Pantholops hodgsonii) based on satellite tracking

    Science.gov (United States)

    Buho, Hoshino; Jiang, Z.; Liu, C.; Yoshida, T.; Mahamut, Halik; Kaneko, M.; Asakawa, M.; Motokawa, M.; Kaji, K.; Wu, X.; Otaishi, N.; Ganzorig, Sumiya; Masuda, R.

    2011-07-01

    The spatial and temporal patterns of the endangered Tibetan antelope or chiru ( Pantholops hodgsonii) have been studied using satellite-based ARGOS platform transmitter terminal (PTT) tracking data. The data was obtained from the satellite tracking of two female Tibetan antelopes that were collared with satellite transmitters and have been tracked from August 2007 to April 2009. Analysis of the locality data (LC) obtained, shows that both antelopes were migrant individuals, they shared the same calving ground surrounding lake Huiten (or Zhuonai lake), but different wintering pastures. Each antelope covered 250-300 km from the wintering to summer pastures. Annual range consisted of a core area that was used for at least 9 months; a calving ground used for a short time (from 8-20 days); and temporal pastures used during migration to and from the calving ground. Seasonal migration cycle was about 3 months, 27-30 days to reach the calving ground; 8-20 days staying there; and 36-40 days returning to the core area. Examination of the spatial distribution during migration showed that both chiru crossed the Qinghai-Tibetan railway (QTR) and the Golmud-Lhasa highway (GLH) at least two times, and reached calving ground (118-120 km from there) in 8 days, maintaining an average speed of 15 km per day. However, the return migration took twice as long (from 14 to 16 days). Each time, after reaching the QTR and GLH, the antelopes spent 20-40 days in that area, probably looking for passages and waiting. So far, we suppose that the QTR and the GLH have become a hindrance to the migration of the Tibetan antelopes and seriously delay their movement to and from the calving area. Extended aggregation of the herds of Tibetan antelopes along the QTR and the GLH may impact negatively with increased mortality among offspring, the spread of various diseases and overgrazing of pastures.

  16. Larger antelopes are sensitive to heat stress throughout all seasons but smaller antelopes only during summer in an African semi-arid environment

    NARCIS (Netherlands)

    Shrestha, A.K.; Wieren, van S.E.; Langevelde, van F.; Fuller, A.; Hetem, R.S.; Meyer, L.; Bie, de S.; Prins, H.H.T.

    2014-01-01

    Heat stress can limit the activity time budget of ungulates due to hyperthermia, which is relevant for African antelopes in ecosystems where temperature routinely increases above 40 °C. Body size influences this thermal sensitivity as large bodied ungulates have a lower surface area to volume ratio

  17. Rocket propulsion elements

    CERN Document Server

    Sutton, George P

    2011-01-01

    The definitive text on rocket propulsion-now revised to reflect advancements in the field For sixty years, Sutton's Rocket Propulsion Elements has been regarded as the single most authoritative sourcebook on rocket propulsion technology. As with the previous edition, coauthored with Oscar Biblarz, the Eighth Edition of Rocket Propulsion Elements offers a thorough introduction to basic principles of rocket propulsion for guided missiles, space flight, or satellite flight. It describes the physical mechanisms and designs for various types of rockets' and provides an unders

  18. Demographic history of the Tibetan antelope Pantholops hodgsoni(chiru)

    Institute of Scientific and Technical Information of China (English)

    Yu-Rong DU; Song-Chang GUO; Zhao-Feng WANG; Hai-Xing CI; Zhen-Yuan CAI; Qian ZHANG; Jian-Ping SU; Jian-Quan LIU

    2010-01-01

    The Tibetan antelope(chiru,Pantholops hodgsoni),a heavily poached species and symbol of the QinghaiTibetan Plateau(QTP),is noted worldwide for its special calving migration.This species originated in the early Quaternary and it is interesting to know how the following climatic oscillations affected its demographic dynamics in the climate-sensitive QTP.In this study,we analyzed the mitochondrial D-loop region from 312 individuals sampled in all of the six major populations.We found high rates of gene flow and little genetic differentiation between populations,suggesting that the calving migration may have homogenized the genetic pool of this species.Both mismatch distribution analyses and coalescent simulations suggested that this species experienced a demographic expansion approximately 600-200 Kyt following the retreat of the large glaciers developed in the QTP at 800-600 Kyr,rather than at the end of the last glacial age,as previously suggested based on a limited sample size.In addition,we found evidence of a chiru population decrease probably related to the human settings at the QTP during the middle Holocene.

  19. Solar Thermal Rocket Propulsion

    Science.gov (United States)

    Sercel, J. C.

    1986-01-01

    Paper analyzes potential of solar thermal rockets as means of propulsion for planetary spacecraft. Solar thermal rocket uses concentrated Sunlight to heat working fluid expelled through nozzle to produce thrust.

  20. Helminths of saiga antelope (Saiga tatarica L. in the “Askania Nova” Biosphere Reserve, Ukraine

    Directory of Open Access Journals (Sweden)

    Zvegintsova N. S.

    2015-09-01

    Full Text Available Analysis of the species composition and community structure of helminths in saiga antelope (Saiga tatarica was performed using multi-year (1979-2013 data collected from the “Askania Nova” Biosphere Reserve, Ukraine. During this period, 31 saiga antelopes of different ages (7 calves, 24 adults were examined; totally, more then 63,900 helminth specimens were collected and identified by morphological criteria. Levels of saiga infection by nematodes were from 39 to 671 EPG (207±132 SD; seasonal fluctuations in saiga infections were insignificant (Mann-Whitney test; p>0.05.

  1. Rockets two classic papers

    CERN Document Server

    Goddard, Robert

    2002-01-01

    Rockets, in the primitive form of fireworks, have existed since the Chinese invented them around the thirteenth century. But it was the work of American Robert Hutchings Goddard (1882-1945) and his development of liquid-fueled rockets that first produced a controlled rocket flight. Fascinated by rocketry since boyhood, Goddard designed, built, and launched the world's first liquid-fueled rocket in 1926. Ridiculed by the press for suggesting that rockets could be flown to the moon, he continued his experiments, supported partly by the Smithsonian Institution and defended by Charles Lindbergh. T

  2. Body temperature variation of South African antelopes in two climatically contrasting environments

    NARCIS (Netherlands)

    Shrestha, A.K.; Wieren, van S.E.; Langevelde, van F.; Fuller, A.; Hetem, R.S.; Meyer, L.C.R.; Bie, de S.; Prins, H.H.T.

    2012-01-01

    To understand the adaptive capacity of a species in response to rapid habitat destruction and climate change, we investigated variation in body temperature (Tb) of three species of antelope, namely eland, blue wildebeest and impala, using abdominally-implanted temperature data loggers. The study was

  3. 77 FR 12526 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2012-03-01

    ... AGENCY 40 CFR Part 52 Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management District and Mojave Desert Quality Management District AGENCY: Environmental Protection Agency... Quality Management District (AVAQMD) and Mojave Desert Air Quality Management District (MDAQMD) portion...

  4. 78 FR 58459 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2013-09-24

    ... AGENCY 40 CFR Part 52 Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management District, Santa Barbara County Air Pollution Control District, South Coast Air Quality Management... Quality Management District (SCAQMD) and Ventura County Air Pollution Control District (VCAPCD)...

  5. 78 FR 49992 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2013-08-16

    ... Quality Management District (AVAQMD) and Ventura County Air Pollution Control District (VCAPCD) portions... AGENCY 40 CFR Part 52 Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management District and Ventura County Air Pollution Control District AGENCY: Environmental Protection...

  6. 77 FR 2496 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2012-01-18

    ... Valley Air Quality Management District (AVAQMD) and Imperial County Air Pollution Control District... AGENCY 40 CFR Part 52 Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management District and Imperial Valley Air Pollution Control District AGENCY: Environmental Protection...

  7. Status of Nilgai antelope as a host of cattle fever tick (Boophilus microplus) and Babesiosis

    Science.gov (United States)

    In 2014 an outbreak of cattle fever ticks, Boophilus microplus, was discovered in Cameron County Texas. It was suspected that the ticks had spread from Mexico into Texas carried by Nilgai antelope, a bovid game animal that ranges freely, across the river between Mexico and the US. Between 9 October ...

  8. Antelope bitterbrush reestablishment: a case study of plant size and browse protection effects.

    Science.gov (United States)

    G. Randy Johnson; Joel P. Okula

    2006-01-01

    After an intense stand-replacement fire in south-central Oregon, 1-y-old (1+0) bareroot seedlings of antelope bitterbrush (Purshia tridentata (Pursh) DC. [Rosaceae]) were outplanted over a 4-y period. Paired-plots were established to examine the benefits of protecting the plants from damage due to animal browsing with Vexar mesh tubing. In the first...

  9. Introduction to rocket science and engineering

    CERN Document Server

    Taylor, Travis S

    2009-01-01

    What Are Rockets? The History of RocketsRockets of the Modern EraRocket Anatomy and NomenclatureWhy Are Rockets Needed? Missions and PayloadsTrajectoriesOrbitsOrbit Changes and ManeuversBallistic Missile TrajectoriesHow Do Rockets Work? ThrustSpecific ImpulseWeight Flow RateTsiolkovsky's Rocket EquationStagingRocket Dynamics, Guidance, and ControlHow Do Rocket Engines Work? The Basic Rocket EngineThermodynamic Expansion and the Rocket NozzleExit VelocityRocket Engine Area Ratio and LengthsRocket Engine Design ExampleAre All Rockets the Same? Solid Rocket EnginesLiquid Propellant Rocket Engines

  10. The flight of uncontrolled rockets

    CERN Document Server

    Gantmakher, F R; Dryden, H L

    1964-01-01

    International Series of Monographs on Aeronautics and Astronautics, Division VII, Volume 5: The Flight of Uncontrolled Rockets focuses on external ballistics of uncontrolled rockets. The book first discusses the equations of motion of rockets. The rocket as a system of changing composition; application of solidification principle to rockets; rotational motion of rockets; and equations of motion of the center of mass of rockets are described. The text looks at the calculation of trajectory of rockets and the fundamentals of rocket dispersion. The selection further focuses on the dispersion of f

  11. Hybrid Rocket Technology

    National Research Council Canada - National Science Library

    Sankaran Venugopal; K K Rajesh; V Ramanujachari

    2011-01-01

    With their unique operational characteristics, hybrid rockets can potentially provide safer, lower-cost avenues for spacecraft and missiles than the current solid propellant and liquid propellant systems...

  12. Road and Street Centerlines, Antelope, Published in 2007, 1:24000 (1in=2000ft) scale, Iron County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — , published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2007. It is described as 'Antelope'. The extent of these data is...

  13. Vulnerability assessment and strategies for the Sheldon National Wildlife Refuge and Hart Mountain National Antelope Refuge Complex : Final report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report provides the results of the Refuge Vulnerability Assessment (RVA) for the Sheldon National Wildlife Refuge and Hart Mountain National Antelope Refuge...

  14. Genetic patterns in forest antelope populations in the Udzungwa Mountains, Tanzania, as inferred from non-invasive sampling

    DEFF Research Database (Denmark)

    Bowkett, Andrew E.; Jones, Trevor; Rovero, Francesco

    2015-01-01

    As for many tropical regions, the evolutionary and demographic status of antelope populations in the Udzungwa Mountains, Tanzania, are poorly resolved. We employed genetic information from 618 faecal samples to assess the status of forest antelope species in terms of their distribution, intraspec...... except the endangered C. spadix. Overall, our results demonstrate the value of non-invasive genetic sampling in studying the distribution and evolution of rarely observed species.......As for many tropical regions, the evolutionary and demographic status of antelope populations in the Udzungwa Mountains, Tanzania, are poorly resolved. We employed genetic information from 618 faecal samples to assess the status of forest antelope species in terms of their distribution......, intraspecific diversity and population subdivision within the Udzungwa landscape. Most species were detected in the majority of forest fragments, except for Philantomba monticola. Phylogenetic analyses were consistent with traditional taxonomy with the exception of Cephalophus harveyi which was paraphyletic...

  15. The Ion Rocket

    Science.gov (United States)

    1961-05-29

    discharge velocity w and the speci- fic impulse lap respectively cannot be increased. At this limit condition the thermal rocket oecouos "choked up...structural quality is 900 t, 3) In the case of an atomic-driven thermal rocket ’,;lth specific Ipipulse ISjy«8C0 sec and thrust to weight ratio « 1, the

  16. Model Rockets and Microchips.

    Science.gov (United States)

    Fitzsimmons, Charles P.

    1986-01-01

    Points out the instructional applications and program possibilities of a unit on model rocketry. Describes the ways that microcomputers can assist in model rocket design and in problem calculations. Provides a descriptive listing of model rocket software for the Apple II microcomputer. (ML)

  17. Analysis and Mapping of Vegetation and Habitat for the Hart Mountain National Antelope Refuge

    Energy Technology Data Exchange (ETDEWEB)

    Tagestad, Jerry D.

    2010-06-01

    The Lakeview, Oregon, office of the U.S. Fish and Wildlife Service (USFWS) contracted Pacific Northwest National Laboratory to classify vegetation communities on Hart Mountain National Antelope Refuge in northeastern Nevada. The objective of the mapping project was to provide USFWS refuge biologists and planners with detailed vegetation and habitat information that can be referenced to make better decisions regarding wildlife resources, fuels and fire risk, and land management. This letter report describes the datasets and methods used to develop vegetation cover type and shrub canopy cover maps for the Hart Mountain National Antelope Refuge. The two map products described in this report are 1) a vegetation cover classification that provides updated information on the vegetation associations occurring on the refuge and 2) a map of shrub canopy cover based on high-resolution images and field data.

  18. Devonian and Mississippian rocks of the northern Antelope Range, Eureka County, Nevada

    Science.gov (United States)

    Hose, Richard Kenneth; Armstrong, A.K.; Harris, A.G.; Mamet, B.L.

    1982-01-01

    Lower through Upper Devonian rocks of the northern Antelope Range, Nev., consist of four formational rank units more than 800 m thick, separated from Mississippian units by an unconformity. The lower three Devonian units, the Beacon Peak Dolomite, McColley Canyon Formation, and Denay Limestone are known in other areas; the top unit, the Fenstermaker Wash Formation, is new. The Mississippian units, more than 280 m thick, are divisible into three units which are unlike coeval units elsewhere, and are herein named the Davis Spring Formation, Kinkead Spring Limestone, and Antelope Range Formation. Systematic sampling of the Devonian sequence has yielded relatively abundant conodonts containing several biostratigraphic ally significant taxa. The Mississippian units contain redeposited conodonts of chiefly Late Devonian and Early Mississippian (Kinderhookian) age together with indigenous Osagean foraminifers and algae in the Kinkead Spring Limestone.

  19. Questing ixodid ticks on the vegetation of sable antelope and multi-herbivore enclosures in Thabazimbi

    Directory of Open Access Journals (Sweden)

    André C. Uys

    2015-03-01

    Full Text Available This survey of ixodid ticks was the first to compare the species composition and population dynamics of free-living ticks in intensive, sable antelope breeding enclosures, now commonplace in commercial wildlife ranching in South Africa, with those of multi-herbivore enclosures. The species composition, abundance and seasonal abundance of questing ixodid ticks on the vegetation in intensive breeding enclosures for sable antelope (Hippotragus niger, on which strategic tick control is practised, were compared with those of ticks in a multi-species herbivore enclosure surrounding the breeding enclosures in which no tick control is practised. A total of eight ixodid tick species were collected by drag-sampling the woodland and grassland habitats in each enclosure type monthly from July 2011 to July 2013. Rhipicephalus decoloratus, a potential vector of fatal tick-borne disease in sable antelopes, was the most abundant, accounting for 65.4% of the total number of ticks collected in the sable enclosures, whilst representing only 25.4% of number of ticks collected in the multi-species herbivore enclosure. Rhipicephalus decoloratus and R. evertsi evertsi were more abundant than R. appendiculatus (both p < 0.05 and Amblyomma hebraeum (p < 0.001 and p < 0.01, respectively. Rhipicephalus decoloratus larvae were collected throughout the year, with peak collections in November 2012 and October to December 2013 in the sable enclosures; and in April/May 2012 and February/April 2013 in the multi-species herbivore enclosure. More R. decoloratus were recovered in the second year than in the first year in the grassland habitat of the sable enclosures (V = 7.0, p < 0.05 possibly as a result of acaricide resistance. The apparent temporal over-abundance of R. decoloratus in sable antelope breeding enclosures, in the face of strategic tick control, is of concern and requires further investigation.

  20. Another Look at Rocket Thrust

    Science.gov (United States)

    Hester, Brooke; Burris, Jennifer

    2012-01-01

    Rocket propulsion is often introduced as an example of Newton's third law. The rocket exerts a force on the exhaust gas being ejected; the gas exerts an equal and opposite force--the thrust--on the rocket. Equivalently, in the absence of a net external force, the total momentum of the system, rocket plus ejected gas, remains constant. The law of…

  1. Another Look at Rocket Thrust

    Science.gov (United States)

    Hester, Brooke; Burris, Jennifer

    2012-01-01

    Rocket propulsion is often introduced as an example of Newton's third law. The rocket exerts a force on the exhaust gas being ejected; the gas exerts an equal and opposite force--the thrust--on the rocket. Equivalently, in the absence of a net external force, the total momentum of the system, rocket plus ejected gas, remains constant. The law of…

  2. Rocket University at KSC

    Science.gov (United States)

    Sullivan, Steven J.

    2014-01-01

    "Rocket University" is an exciting new initiative at Kennedy Space Center led by NASA's Engineering and Technology Directorate. This hands-on experience has been established to develop, refine & maintain targeted flight engineering skills to enable the Agency and KSC strategic goals. Through "RocketU", KSC is developing a nimble, rapid flight engineering life cycle systems knowledge base. Ongoing activities in RocketU develop and test new technologies and potential customer systems through small scale vehicles, build and maintain flight experience through balloon and small-scale rocket missions, and enable a revolving fresh perspective of engineers with hands on expertise back into the large scale NASA programs, providing a more experienced multi-disciplined set of systems engineers. This overview will define the Program, highlight aspects of the training curriculum, and identify recent accomplishments and activities.

  3. 航天发射场导流槽综合性能评价指标体系研究%Research on Global Performance Design Method of Blast Deflector in Rocket Launch Site

    Institute of Scientific and Technical Information of China (English)

    刘利宏; 张志成; 周旭

    2014-01-01

    导流槽是航天发射场的重要核心设施,作用是排导火箭发动机产生的高温高压燃气射流。基于计算流体动力学原理,利用理论分析、试验研究和数值仿真方法,开展发动机燃气射流在导流槽内部流动特性以及射流噪声传播和辐射特性等火箭发射环境效应问题研究,对导流槽设计中关心的冲击、烧蚀、通畅性以及喷水冷却系统的效率和噪声防护等问题进行评价,初步建立导流槽优化设计综合性能评价指标,为导流槽综合性能设计提供重要的参考依据。%Blast deflector is one of the key infrastructures in the rocket launch site which deflects the high temperature and high pressure jet emitted by the rocket engine .Based on the computational flu-id dynamics theory , theoretical analysis , experimental investigations and numerical simulation were adopted to study the launch environment effects including the flow characteristic of jet engine flame in blast deflector and the disseminated property of jet engine noise .Issues concerning the flow safety and smoothness and the efficiency of spray system in design of blast deflector were evaluated .The performance assessment index of blast deflector was preliminarily set up by multiple analysis methods which may provide reference for the global performance optimization design of the blast deflector .

  4. "Antelope": a hybrid-logic model checker for branching-time Boolean GRN analysis

    Directory of Open Access Journals (Sweden)

    Arellano Gustavo

    2011-12-01

    Full Text Available Abstract Background In Thomas' formalism for modeling gene regulatory networks (GRNs, branching time, where a state can have more than one possible future, plays a prominent role. By representing a certain degree of unpredictability, branching time can model several important phenomena, such as (a asynchrony, (b incompletely specified behavior, and (c interaction with the environment. Introducing more than one possible future for a state, however, creates a difficulty for ordinary simulators, because infinitely many paths may appear, limiting ordinary simulators to statistical conclusions. Model checkers for branching time, by contrast, are able to prove properties in the presence of infinitely many paths. Results We have developed Antelope ("Analysis of Networks through TEmporal-LOgic sPEcifications", http://turing.iimas.unam.mx:8080/AntelopeWEB/, a model checker for analyzing and constructing Boolean GRNs. Currently, software systems for Boolean GRNs use branching time almost exclusively for asynchrony. Antelope, by contrast, also uses branching time for incompletely specified behavior and environment interaction. We show the usefulness of modeling these two phenomena in the development of a Boolean GRN of the Arabidopsis thaliana root stem cell niche. There are two obstacles to a direct approach when applying model checking to Boolean GRN analysis. First, ordinary model checkers normally only verify whether or not a given set of model states has a given property. In comparison, a model checker for Boolean GRNs is preferable if it reports the set of states having a desired property. Second, for efficiency, the expressiveness of many model checkers is limited, resulting in the inability to express some interesting properties of Boolean GRNs. Antelope tries to overcome these two drawbacks: Apart from reporting the set of all states having a given property, our model checker can express, at the expense of efficiency, some properties that ordinary

  5. Gaseous Helium Reclamation at Rocket Test Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The ability to restore large amounts of vented gaseous helium (GHe) at rocket test sites preserves the GHe and reduces operating cost. The used GHe is vented into...

  6. Rocket noise - A review

    Science.gov (United States)

    McInerny, S. A.

    1990-10-01

    This paper reviews what is known about far-field rocket noise from the controlled studies of the late 1950s and 1960s and from launch data. The peak dimensionless frequency, the dependence of overall sound power on exhaust parameters, and the directivity of the overall sound power of rockets are compared to those of subsonic jets and turbo-jets. The location of the dominant sound source in the rocket exhaust plume and the mean flow velocity in this region are discussed and shown to provide a qualitative explanation for the low peak Strouhal number, fD(e)/V(e), and large angle of maximum directivity. Lastly, two empirical prediction methods are compared with data from launches of a Titan family vehicle (two, solid rocket motors of 5.7 x 10 to the 6th N thrust each) and the Saturn V (five, liquid oxygen/rocket propellant engines of 6.7 x 10 to the 6th N thrust, each). The agreement is favorable. In contrast, these methods appear to overpredict the far-field sound pressure levels generated by the Space Shuttle.

  7. Analysis of Tests of Subsurface Injection, Storage, and Recovery of Freshwater in Lancaster, Antelope Valley, California

    Science.gov (United States)

    Phillips, Steven P.; Carlson, Carl S.; Metzger, Loren F.; Howle, James F.; Galloway, Devin L.; Sneed, Michelle; Ikehara, Marti E.; Hudnut, Kenneth W.; King, Nancy E.

    2003-01-01

    Ground-water levels in Lancaster, California, declined more than 200 feet during the 20th century, resulting in reduced ground-water supplies and more than 6 feet of land subsidence. Facing continuing population growth, water managers are seeking solutions to these problems. Injection of imported, treated fresh water into the aquifer system when it is most available and least expensive, for later use during high-demand periods, is being evaluated as part of a management solution. The U.S. Geological Survey, in cooperation with the Los Angeles County Department of Public Works and the Antelope Valley-East Kern Water Agency, monitored a pilot injection program, analyzed the hydraulic and subsidence-related effects of injection, and developed a simulation/optimization model to help evaluate the effectiveness of using existing and proposed wells in an injection program for halting the decline of ground-water levels and avoiding future land subsidence while meeting increasing ground-water demand. A variety of methods were used to measure aquifer-system response to injection. Water levels were measured continuously in nested (multi-depth) piezometers and monitoring wells and periodically in other wells that were within several miles of the injection site. Microgravity surveys were done to estimate changes in the elevation of the water table in the absence of wells and to estimate specific yield. Aquifer-system deformation was measured directly and continuously using a dual borehole extensometer and indirectly using continuous Global Positioning System (GPS), first-order spirit leveling, and an array of tiltmeters. The injected water and extracted water were sampled periodically and analyzed for constituents, including chloride and trihalomethanes. Measured injection rates of about 750 gallons per minute (gal/min) per well at the injection site during a 5-month period showed that injection at or above the average extraction rates at that site (about 800 gal/min) was

  8. Rocket Flight Path

    Directory of Open Access Journals (Sweden)

    Jamie Waters

    2014-09-01

    Full Text Available This project uses Newton’s Second Law of Motion, Euler’s method, basic physics, and basic calculus to model the flight path of a rocket. From this, one can find the height and velocity at any point from launch to the maximum altitude, or apogee. This can then be compared to the actual values to see if the method of estimation is a plausible. The rocket used for this project is modeled after Bullistic-1 which was launched by the Society of Aeronautics and Rocketry at the University of South Florida.

  9. Rockets in World War I

    Science.gov (United States)

    2004-01-01

    World War I enlisted rockets once again for military purposes. French pilots rigged rockets to the wing struts of their airplanes and aimed them at enemy observation balloons filled with highly inflammable hydrogen.

  10. An Evaluation Of Rocket Parameters

    Directory of Open Access Journals (Sweden)

    J. N. Beri

    1959-07-01

    Full Text Available The dependence of conventional parameters of internal ballistics of Solid Propellant Rockets using external burning cruciform charge, on the geometry of charge aad rocket motor is discussed and results applied in a special case.

  11. Anthrax immunization of free-ranging Roan Antelope Hippotragus Equinus in the Kruger National Park

    Directory of Open Access Journals (Sweden)

    V. de Vos

    1973-07-01

    Full Text Available An aerial method of immunization is presented as afeasible means of vaccinating free-ranging roan antelope Hippotragus equinus against anthrax in the Kruger National Park. Themethod is described in detail and the results, obtained aftertwo consecutive years of application, are noted, tabulated andevaluated. A helicopter and a fixed wing aircraft were success-fully utilized in the location of widely dispersed roan antelopeherds and to bring the operator within effective firing rangeof the animal to be darted. A disposable projectile syringe,which simultaneously administers vaccine and effectively marksthe animal for later identification, is considered a vital part inthe successful implementation of the aerial method of immunization.

  12. Baking Soda and Vinegar Rockets

    Science.gov (United States)

    Claycomb, James R.; Zachary, Christopher; Tran, Quoc

    2009-01-01

    Rocket experiments demonstrating conservation of momentum will never fail to generate enthusiasm in undergraduate physics laboratories. In this paper, we describe tests on rockets from two vendors that combine baking soda and vinegar for propulsion. The experiment compared two analytical approximations for the maximum rocket height to the…

  13. Baking Soda and Vinegar Rockets

    Science.gov (United States)

    Claycomb, James R.; Zachary, Christopher; Tran, Quoc

    2009-01-01

    Rocket experiments demonstrating conservation of momentum will never fail to generate enthusiasm in undergraduate physics laboratories. In this paper, we describe tests on rockets from two vendors that combine baking soda and vinegar for propulsion. The experiment compared two analytical approximations for the maximum rocket height to the…

  14. Introduction to Rocket Propulsion

    Science.gov (United States)

    1991-12-01

    Von Braun; 1966. 4. Introduction to Ordnance Technology; IHSP 76-129; 1976. 5. Physics; D. Halliday and R. Resnick ; 1963. 6. Physics Tells Why: 0...to Luke Sky- walker in Star Wars when he said "Don’t get cocky." We never plan for EVERYTHING, though we like to think we do. As we’ve said, rocket

  15. Low toxicity rocket propellants

    NARCIS (Netherlands)

    Wink, J.

    2014-01-01

    Hydrazine (N2H4) and its hypergolic mate nitrogen tetroxide (N2O4) are used on virtually all spacecraft and on a large number of launch vehicles. In recent years however, there has been an effort in identifying and developing alternatives to replace hydrazine as a rocket propellant.

  16. This "Is" Rocket Science!

    Science.gov (United States)

    Keith, Wayne; Martin, Cynthia; Veltkamp, Pamela

    2013-01-01

    Using model rockets to teach physics can be an effective way to engage students in learning. In this paper, we present a curriculum developed in response to an expressed need for helping high school students review physics equations in preparation for a state-mandated exam. This required a mode of teaching that was more advanced and analytical…

  17. The Relativistic Rocket

    Science.gov (United States)

    Antippa, Adel F.

    2009-01-01

    We solve the problem of the relativistic rocket by making use of the relation between Lorentzian and Galilean velocities, as well as the laws of superposition of successive collinear Lorentz boosts in the limit of infinitesimal boosts. The solution is conceptually simple, and technically straightforward, and provides an example of a powerful…

  18. Rocketing to the Skies

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    ONE sunny morning,we startedfor Yanqi Lake,Huairou District,Beijing,to try“rocket bungy”,so farthe only facility for this sport inChina.On the way there,wequestioned our courage and heartendurance. Entering the gate we saw,towering over a banner saying,

  19. Low toxicity rocket propellants

    NARCIS (Netherlands)

    Wink, J.

    2014-01-01

    Hydrazine (N2H4) and its hypergolic mate nitrogen tetroxide (N2O4) are used on virtually all spacecraft and on a large number of launch vehicles. In recent years however, there has been an effort in identifying and developing alternatives to replace hydrazine as a rocket propellant.

  20. Ibex-associated malignant catarrhal fever-like disease in a group of bongo antelope (Tragelaphus euryceros)

    Science.gov (United States)

    A private zoological facility experienced an outbreak of fatal malignant catarrhal fever (MCF) in a group of bongo antelope (Tragelaphus euryceros). Three periparturient female bongos exhibited an acute onset of anorexia beginning ~6 weeks after being housed with a Nubian ibex (Capra nubiana). Disea...

  1. Anthelmintic efficacy in captive wild impala antelope (Aepyceros melampus) in Lusaka, Zambia.

    Science.gov (United States)

    Nalubamba, King S; Mudenda, Ntombi B

    2012-05-25

    There has been an increase in the number of wild ungulates kept in captivity for ecotourism and conservation in Zambia and these animals are susceptible to a number of diseases including gastrointestinal helminth infections. Surveys to determine anthelmintic efficacy to gastrointestinal nematodes in captive-wildlife are not common and there have been no reports of anthelmintic resistance in captive-wildlife in Zambia. This study was carried out to determine the efficacy of the benzimidazole anthelmintic fenbendazole in captive wild impala (Aepyceros melampus) in Zambia. During the month of April 2011, at the end of the rainy season, the faecal egg count reduction test was performed at a private game facility for assessing anthelmintic efficacy of oral fenbendazole and the anthelmintic treatment showed an efficacy of 90%. Haemonchus spp. and Trichostrongylus spp. were the predominant genera present before treatment, but Haemonchus spp. larvae were the only genus recovered from the faecal cultures after anthelmintic treatment. This represents the first documentation of anthelmintic treatment failure in captive wild-antelopes in Zambia. It also demonstrated the ineffectiveness of the common traditional practice of deworming captive-wild antelopes at the end of the rainy season due to the rapid re-infection of impala that occurs due to high pasture infectivity. Suggestions on changes to current anthelmintic use/practices that will make them more efficacious and reduce the possibility of development of anthelmintic resistance in captive wild game in Zambia are also made.

  2. Tuberculosis in Kafue lechwe antelopes (Kobus leche Kafuensis) of the Kafue Basin in Zambia.

    Science.gov (United States)

    Munyeme, M; Muma, J B; Siamudaala, V M; Skjerve, E; Munang'andu, H M; Tryland, M

    2010-07-01

    Tuberculosis (TB) has been reported in the Kafue lechwe antelopes (Kobus leche Kafuensis) of Zambia. However, previous reports are restricted to the southern parts in Lochinvar, where only old male animals were investigated. This study was conducted to gather epidemiological information on TB in Lechwe antelopes across sexes and age groups in relation to other explanatory variables of disease occurrence in the Kafue Basin. Animals were hunted under a special licence to investigate diseases in the Kafue Basin during the 2004, 2005 and 2008 hunting seasons. Histopathology, acid-fast staining and mycobacterial culturing from tissue samples were conducted. A total of 119 animals were slaughtered with an estimated age range of 2.5-20 years. Of these, 29 (24.3% [95% CI: 16.5, 32.3%]) had necropsy lesions suggestive of tuberculosis, of which 21 (17.6% [95% CI: 10.7, 24.6%]) tested positive on acid-fast staining while 33 (27.7% [95% CI: 19.6, 35.9%]) showed culture and colony morphological characteristics suggestive of Mycobacterium species. On univariate analysis, animals with poor body condition were twice as likely to have tuberculosis associated lesions as those having good body conditions (OR=2.3, 95% CI: 0.6, 9.3%). Based on lesion distribution, a respiratory route of mycobacterial infection is intimated.

  3. Hybrid Rocket Technology

    Directory of Open Access Journals (Sweden)

    Sankaran Venugopal

    2011-04-01

    Full Text Available With their unique operational characteristics, hybrid rockets can potentially provide safer, lower-cost avenues for spacecraft and missiles than the current solid propellant and liquid propellant systems. Classical hybrids can be throttled for thrust tailoring, perform in-flight motor shutdown and restart. In classical hybrids, the fuel is stored in the form of a solid grain, requiring only half the feed system hardware of liquid bipropellant engines. The commonly used fuels are benign, nontoxic, and not hazardous to store and transport. Solid fuel grains are not highly susceptible to cracks, imperfections, and environmental temperature and are therefore safer to manufacture, store, transport, and use for launch. The status of development based on the experience of the last few decades indicating the maturity of the hybrid rocket technology is given in brief.Defence Science Journal, 2011, 61(3, pp.193-200, DOI:http://dx.doi.org/10.14429/dsj.61.518

  4. Liquid rocket engine injectors

    Science.gov (United States)

    Gill, G. S.; Nurick, W. H.

    1976-01-01

    The injector in a liquid rocket engine atomizes and mixes the fuel with the oxidizer to produce efficient and stable combustion that will provide the required thrust without endangering hardware durability. Injectors usually take the form of a perforated disk at the head of the rocket engine combustion chamber, and have varied from a few inches to more than a yard in diameter. This monograph treats specifically bipropellant injectors, emphasis being placed on the liquid/liquid and liquid/gas injectors that have been developed for and used in flight-proven engines. The information provided has limited application to monopropellant injectors and gas/gas propellant systems. Critical problems that may arise during injector development and the approaches that lead to successful design are discussed.

  5. Liquid Rocket Engine Testing

    Science.gov (United States)

    2016-10-21

    booster rocket engines • 6000-10000 psia capabilities – Can use gaseous nitrogen, helium, or hydrogen to pressurize propellant tanks 9Distribution A...Approved for Public Release; Distribution Unlimited. PA Clearance 16493 Simplified Test Stand Layout Oxidizer  TankFuel  Tank High  Pressure   Gas (GN2...requires large, complex facilities to deliver propellant at the proper pressure , temperature, and flow rates • The enormous energies involved

  6. Solid propellant rocket motor

    Science.gov (United States)

    Dowler, W. L.; Shafer, J. I.; Behm, J. W.; Strand, L. D. (Inventor)

    1973-01-01

    The characteristics of a solid propellant rocket engine with a controlled rate of thrust buildup to a desired thrust level are discussed. The engine uses a regressive burning controlled flow solid propellant igniter and a progressive burning main solid propellant charge. The igniter is capable of operating in a vacuum and sustains the burning of the propellant below its normal combustion limit until the burning propellant surface and combustion chamber pressure have increased sufficiently to provide a stable chamber pressure.

  7. Nuclear Thermal Rocket Propulsion Systems

    Science.gov (United States)

    2007-11-02

    NUCLEAR THERMAL ROCKET PROPULSION SYSTEMS, IAA WHITE PAPER PARIS, FRANCE, MARCH 2005 Lt Col Timothy J. Lawrence U.S. Air Force Academy...YYYY) 18-03-2005 2. REPORT TYPE White Paper 3. DATES COVERED (From - To) 18 Mar 2005 4. TITLE AND SUBTITLE NUCLEAR THERMAL ROCKET PROPULSION...reduce radiation exposure, is to have a high energy system like a nuclear thermal rocket that can get the payload to the destination in the fastest

  8. Rocket Assembly and Checkout Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Integrates, tests, and calibrates scientific instruments flown on sounding rocket payloads. The scientific instruments are assembled on an optical bench;...

  9. Rocket + Science = Dialogue

    Science.gov (United States)

    Morris,Bruce; Sullivan, Greg; Burkey, Martin

    2010-01-01

    It's a cliche that rocket engineers and space scientists don t see eye-to-eye. That goes double for rocket engineers working on human spaceflight and scientists working on space telescopes and planetary probes. They work fundamentally different problems but often feel that they are competing for the same pot of money. Put the two groups together for a weekend, and the results could be unscientific or perhaps combustible. Fortunately, that wasn't the case when NASA put heavy lift launch vehicle designers together with astronomers and planetary scientists for two weekend workshops in 2008. The goal was to bring the top people from both groups together to see how the mass and volume capabilities of NASA's Ares V heavy lift launch vehicle could benefit the science community. Ares V is part of NASA's Constellation Program for resuming human exploration beyond low Earth orbit, starting with missions to the Moon. In the current mission scenario, Ares V launches a lunar lander into Earth orbit. A smaller Ares I rocket launches the Orion crew vehicle with up to four astronauts. Orion docks with the lander, attached to the Ares V Earth departure stage. The stage fires its engine to send the mated spacecraft to the Moon. Standing 360 feet high and weighing 7.4 million pounds, NASA's new heavy lifter will be bigger than the 1960s-era Saturn V. It can launch almost 60 percent more payload to translunar insertion together with the Ares I and 35 percent more mass to low Earth orbit than the Saturn V. This super-sized capability is, in short, designed to send more people to more places to do more things than the six Apollo missions.

  10. Overt female mate competition and preference for central males in a lekking antelope.

    Science.gov (United States)

    Bro-Jørgensen, Jakob

    2002-07-01

    In mammals, there exists only scant evidence of female mate choice in species mating on arenas, so-called leks. This has led to hypotheses of lek evolution that are based on benefits to females from reduced harassment by males, low predation risk, or improved availability of scarce nutrients. Here I report that female topi antelopes (Damaliscus lunatus) compete aggressively for matings with preferred males on central lek territories. Females fight at higher rates and more likely disrupt mating attempts of others in the lek center than elsewhere. Contrary to the predictions of the alternative hypotheses, food resources were insignificant, and harassment levels and estimated predation risk were higher on than off lek. These results clearly demonstrate female competition for mates in a lekking mammal in which a female chooses between males for the sole purpose of mating. The finding suggests that the forces leading to lek evolution in mammals and birds may be more similar than previously acknowledged.

  11. A WILDLIFE MONITORING SYSTEM BASED ON TIANDITU AND BEIDOU: IN CASE OF THE TIBETAN ANTELOPE

    Directory of Open Access Journals (Sweden)

    H. Zhang

    2016-06-01

    Full Text Available Positioning and tracking wildlife is already being an effective way to collect biological information for research and species of wildlife protection. The common technologies of tracking wildlife are divided into several categories, such as radio tracking technology, GPS tracking system, radio frequency identification technology (RFID, and SIM card based technology. Some positive results achieved from these technologies, but there are some problems in location accuracy, price of the system. Taking the case of the protection of the Tibetan antelope, this paper introduces a wildlife monitoring system based on Tianditu and Beidou navigation satellite system. The system consists of two parts: real-time location system and 3D display system. The practical application demonstrates that the system is stable, and data transmission is reliable with lower construction cost, which can improve the capability of national rare wildlife monitoring and protection effectively.

  12. Evaluation of Brucella abortus strain RB51 and strain 19 in pronghorn antelope

    Science.gov (United States)

    Elzer, P.H.; Smith, J.; Roffe, T.; Kreeger, T.; Edwards, J.; Davis, D.

    2002-01-01

    Free-roaming elk and bison in the Greater Yellowstone Area remain the only wildlife reservoirs for Brucella abortus in the United States, and the large number of animals and a lack of holding facilities make it unreasonable to individually vaccinate each animal. Therefore, oral delivery is being proposed as a possible option to vaccinate these wild ungulates. One of the main problems associated with oral vaccination is the potential exposure of nontarget species to the vaccines. The purpose of this study was to determine the effects of two Brucella vaccines, strain 19 (S19) and the rough strain RB51 (SRB51), in pregnant pronghorn antelope. We conclude that S19 and SRB51 rarely colonize maternal and fetal tissues of pregnant pronghorn and were not associated with fetal death. Oral delivery of either vaccine at this dose appears to be nonhazardous to pregnant pronghorn.

  13. Ibex-associated malignant catarrhal fever in a bongo antelope (Tragelaphus euryceros).

    Science.gov (United States)

    Okeson, Danelle M; Garner, Michael M; Taus, Naomi S; Li, Hong; Coke, Rob L

    2007-09-01

    A 4-yr-old male bongo antelope (Tragelaphus euryceros) died after an acute clinical course involving a febrile illness, anorexia, lethargy, minor oculonasal discharge, and diarrhea. Histologic lesions were compatible with malignant catarrhal fever (MCF). Polymerase chain reaction (PCR) revealed an amplified region of a herpesviral DNA polymerase gene sequence nearly identical to that of a MCF virus previously identified in Nubian ibex (Capra nubiana). The bongo had been housed across from an exhibit containing Nubian ibex that tested positive for MCF viral antibodies by competitive inhibition enzyme-linked immunosorbent assay. Further testing of the zoo's ibex via PCR also revealed viral DNA sequences nearly identical to those found in the bongo's tissues.

  14. a Wildlife Monitoring System Based on Tianditu and Beidou: in Case of the Tibetan Antelope

    Science.gov (United States)

    Zhang, Hongping; Jiang, Jie; Wei, Dong; Jiang, Jie

    2016-06-01

    Positioning and tracking wildlife is already being an effective way to collect biological information for research and species of wildlife protection. The common technologies of tracking wildlife are divided into several categories, such as radio tracking technology, GPS tracking system, radio frequency identification technology (RFID), and SIM card based technology. Some positive results achieved from these technologies, but there are some problems in location accuracy, price of the system. Taking the case of the protection of the Tibetan antelope, this paper introduces a wildlife monitoring system based on Tianditu and Beidou navigation satellite system. The system consists of two parts: real-time location system and 3D display system. The practical application demonstrates that the system is stable, and data transmission is reliable with lower construction cost, which can improve the capability of national rare wildlife monitoring and protection effectively.

  15. Detection and characterisation of papillomavirus in skin lesions of giraffe and sable antelope in South Africa

    Directory of Open Access Journals (Sweden)

    E. van Dyk

    2011-04-01

    Full Text Available Papillomavirus was detected electron microscopically in cutaneous fibropapillomas of a giraffe (Giraffa camelopardalis and a sable antelope (Hippotragus niger. The virus particles measured 45 nm in diameter. Histopathologically, the lesions showed histopathological features similar to those of equine sarcoid as well as positive immunoperoxidase-staining of tissue sections for papillomavirus antigen. Polymerase chain reaction (PCR detected bovine papillomavirus (BPV DNA. Bovine papillomavirus-1 was characterised by real-time PCR in the sable and giraffe, and cloning and sequencing of the PCR product revealed a similarity to BPV-1. As in the 1st giraffe, the lesions from a 2nd giraffe revealed locally malignant pleomorphism, possibly indicating the lesional end-point of papilloma infection. Neither virus particles nor positively staining papillomavirus antigen could be demonstrated in the 2nd giraffe but papillomavirus DNA was detected by real-time PCR which corresponded with BPV-1 and BPV-2.

  16. Bayesian, Maximum Parsimony and UPGMA Models for Inferring the Phylogenies of Antelopes Using Mitochondrial Markers

    Directory of Open Access Journals (Sweden)

    Haseeb A. Khan

    2008-01-01

    Full Text Available This investigation was aimed to compare the inference of antelope phylogenies resulting from the 16S rRNA, cytochrome-b (cyt-b and d-loop segments of mitochondrial DNA using three different computational models including Bayesian (BA, maximum parsimony (MP and unweighted pair group method with arithmetic mean (UPGMA. The respective nucleotide sequences of three Oryx species (Oryx leucoryx, Oryx dammah and Oryx gazella and an out-group (Addax nasomaculatus were aligned and subjected to BA, MP and UPGMA models for comparing the topologies of respective phylogenetic trees. The 16S rRNA region possessed the highest frequency of conserved sequences (97.65% followed by cyt-b (94.22% and d-loop (87.29%. There were few transitions (2.35% and none transversions in 16S rRNA as compared to cyt-b (5.61% transitions and 0.17% transversions and d-loop (11.57% transitions and 1.14% transversions while com- paring the four taxa. All the three mitochondrial segments clearly differentiated the genus Addax from Oryx using the BA or UPGMA models. The topologies of all the gamma-corrected Bayesian trees were identical irrespective of the marker type. The UPGMA trees resulting from 16S rRNA and d-loop sequences were also identical (Oryx dammah grouped with Oryx leucoryx to Bayesian trees except that the UPGMA tree based on cyt-b showed a slightly different phylogeny (Oryx dammah grouped with Oryx gazella with a low bootstrap support. However, the MP model failed to differentiate the genus Addax from Oryx. These findings demonstrate the efficiency and robustness of BA and UPGMA methods for phylogenetic analysis of antelopes using mitochondrial markers.

  17. Engineering geology considerations for park planning, Antelope Island State Park, Davis County, Utah

    Science.gov (United States)

    Hecker, Suzanne; Case, William F.; King, Jon K.; Willis, Grant C.

    2000-01-01

    Report: 00-1 In the mid-1980s, historically high levels of Great Salt Lake caused damage to park facilities on Antelope Island and destroyed the causeway linking the park to the mainland. Information on the engineering geology of Antelope Islandcan be used to improve park facilities and reduce the risk from geologic hazards and poor construction conditions. Certain characteristics of the geologic environment need to be considered in park planning. During wet cycles, Great Salt Lake may reach static levels of 4,217 feet (1,285.3 m), and wave- and wind-elevated levels locally may reach 6.5 feet (2 m) higher. A probabilistic assessment of the earthquake ground-shaking hazard along the Wasatch Front indicates that peak ground accelerations of approximately 0.20 to 0.30 g have a one-in-ten chance of being exceeded in 50 years on the island. A slope-failure hazard exists locally in colluvial and Lake Bonneville deposits, along the modern shore, and beneath cliffs. Flash-flood and debris-flow hazards exist on alluvial fans. Areas in the southern two-thirds of the island may have a relatively high potential for radon emission. Particular soil types on the island may be expansive, compressible, erodible, impermeable, or susceptible to liquefaction or hydrocompaction. The distribution of most geologic hazards can be defined, and many locations on the island have conditions suitable for construction. Lacustrine sand and gravel deposits are wide-spread and have engineering characteristics that are generally favorable for foundations. However, facilities and roads built close to the modern shoreline may be susceptible to lake flooding and erosion, slope failures, shallow ground water, and burial by active sand dunes. Well-graded (poorly sorted) alluvial-fan deposits are generally most suitable for wastewater disposal, although they may be subject to flooding or be underlain by low-permeability, fine-grained lacustrine deposits.

  18. Mars Rocket Propulsion System

    Science.gov (United States)

    Zubrin, Robert; Harber, Dan; Nabors, Sammy

    2008-01-01

    A report discusses the methane and carbon monoxide/LOX (McLOx) rocket for ascent from Mars as well as other critical space propulsion tasks. The system offers a specific impulse over 370 s roughly 50 s higher than existing space-storable bio-propellants. Current Mars in-situ propellant production (ISPP) technologies produce impure methane and carbon monoxide in various combinations. While separation and purification of methane fuel is possible, it adds complexity to the propellant production process and discards an otherwise useful fuel product. The McLOx makes such complex and wasteful processes unnecessary by burning the methane/CO mixtures produced by the Mars ISPP systems without the need for further refinement. Despite the decrease in rocket-specific impulse caused by the CO admixture, the improvement offered by concomitant increased propellant density can provide a net improvement in stage performance. One advantage is the increase of the total amount of propellant produced, but with a decrease in mass and complexity of the required ISPP plant. Methane/CO fuel mixtures also may be produced by reprocessing the organic wastes of a Moon base or a space station, making McLOx engines key for a human Lunar initiative or the International Space Station (ISS) program. Because McLOx propellant components store at a common temperature, very lightweight and compact common bulkhead tanks can be employed, improving overall stage performance further.

  19. What fuel for a rocket?

    CERN Document Server

    Miranda, E N

    2012-01-01

    Elementary concepts from general physics and thermodynamics have been used to analyze rocket propulsion. Making some reasonable assumptions, an expression for the exit velocity of the gases is found. From that expression one can conclude what are the desired properties for a rocket fuel.

  20. Rocket launchers as passive controllers

    Science.gov (United States)

    Cochran, J. E., Jr.; Gunnels, R. T.; McCutchen, R. K., Jr.

    1981-12-01

    A concept is advanced for using the motion of launchers of a free-flight launcher/rocket system which is caused by random imperfections of the rockets launched from it to reduce the total error caused by the imperfections. This concept is called 'passive launcher control' because no feedback is generated by an active energy source after an error is sensed; only the feedback inherent in the launcher/rocket interaction is used. Relatively simple launcher models with two degrees of freedom, pitch and yaw, were used in conjunction with a more detailed, variable-mass model in a digital simulation code to obtain rocket trajectories with and without thrust misalignment and dynamic imbalance. Angular deviations of rocket velocities and linear deviations of the positions of rocket centers of mass at burnout were computed for cases in which the launcher was allowed to move ('flexible' launcher) and was constrained so that it did not rotate ('rigid' launcher) and ratios of flexible to rigid deviations were determined. Curves of these error ratios versus launcher frequency are presented. These show that a launcher which has a transverse moment of inertia about its pivot point of the same magnitude as that of the centroidal transverse moments of inertia of the rockets launched from it can be tuned to passively reduce the errors caused by rocket imperfections.

  1. Diet of the Four-horned Antelope Tetracerus quadricornis (De Blainville, 1816 in the Churia Hills of Nepal

    Directory of Open Access Journals (Sweden)

    Amar Kunwar

    2016-05-01

    Full Text Available The food composition of the Four-horned Antelope Tetracerus quadricornis was studied in the Churia Hills of Nepal during summer, monsoon and the winter seasons of 2012–2013.  Microhistological technique was used to determine the diet.  The Four-horned Antelope was found to be a mixed feeder feeding on trees, shrubs, forbs, grasses and climbers.  Trees and shrubs contribute the major percentage of diet in all the three seasons.  The Gramineae family is consumed in highest proportion.  Mitragyna parvifolia, Bridelia retusa, Bambusa vulgaris, Hymenodictyon sp. and Ziziphus mauritiana are major tree species while Barleria cristata, Pogostemon benghalensis, Achyranthes sp., Clerodendrum viscosum are among shrubs.  Ageratum conyzoides and Blumea virens are the main forbs Eulaliopsis binata and Imperata cylindrica are the principal grass species.  Climber Trachelospermum lucidum is consumed in a small proportion.  Grasses in monsoon were consumed distinctly at a higher percentage than during the other two seasons.  The Four-horned Antelopes are concentrated feeders and browsers with a generalized feeding strategy. Similar studies need to be conducted in other landscapes and with sympatric and potential competitor species to understand its niche overlaps and degree of competition. 

  2. Challenges faced in the conservation of rare antelope: a case study on the northern basalt plains of the Kruger National Park

    Directory of Open Access Journals (Sweden)

    C.C. Grant

    2002-12-01

    Full Text Available The conservation of rare antelope has long been one of the goals of the Kruger National Park. The roan antelope Hippotragus equinus, and to a lesser extent the tsessebe Damaliscus lunatus, represent low-density species or rare antelope in the park. Specific management approaches representing the older equilibrium approach, have been employed to conserve these antelope. Of these, the supply of artificial water over many decades was the most resource intensive. The sudden, severe drop in the roan antelope population towards the end of the 1980s was unexpected and, retrospectively, attributed to the development of a high density of perennial waterpoints. The postulated mechanism was that the perennial presence of water allowed Burchell’s zebra Equus burchelli to stay permanently in an area that was previously only seasonally accessible. The combined effect of a long, dry climatic cycle, high numbers of zebra and their associated predators was proposed to be the cause of this decline. As part of the new nature evolving or ecosystem resilience approach, twelve artificial waterpoints were closed in the prime roan antelope habitat in 1994 in an attempt to move the zebra out of this area. The zebra numbers declined as the rainfall increased. Closure of waterholes clearly led to redistribution of zebra numbers on the northern plains, zebra tending to avoid areas within several kilometres of closed waterpoints. However, at a larger scale, regional densities appeared similar in areas with and without closed waterpoints. There was an initial drop in the lion numbers in 1995, after which they stabilised. In spite of an improvement in the grass species composition and an increase in biomass the roan antelope population did not increase. The complexity of maintaining a population at the edge of their distribution and the problems associated with the conservation of such populations are discussed in terms of management options and monitoring approaches that

  3. Nuclear Rocket Engine Reactor

    CERN Document Server

    Lanin, Anatoly

    2013-01-01

    The development of a nuclear rocket engine reactor (NRER ) is presented in this book. The working capacity of an active zone NRER under mechanical and thermal load, intensive neutron fluxes, high energy generation (up to 30 MBT/l) in a working medium (hydrogen) at temperatures up to 3100 K is displayed. Design principles and bearing capacity of reactors area discussed on the basis of simulation experiments and test data of a prototype reactor. Property data of dense constructional, porous thermal insulating and fuel materials like carbide and uranium carbide compounds in the temperatures interval 300 - 3000 K are presented. Technological aspects of strength and thermal strength resistance of materials are considered. The design procedure of possible emergency processes in the NRER is developed and risks for their origination are evaluated. Prospects of the NRER development for pilotless space devices and piloted interplanetary ships are viewed.

  4. Rocket propulsion elements - An introduction to the engineering of rockets (6th revised and enlarged edition)

    Science.gov (United States)

    Sutton, George P.

    The subject of rocket propulsion is treated with emphasis on the basic technology, performance, and design rationale. Attention is given to definitions and fundamentals, nozzle theory and thermodynamic relations, heat transfer, flight performance, chemical rocket propellant performance analysis, and liquid propellant rocket engine fundamentals. The discussion also covers solid propellant rocket fundamentals, hybrid propellant rockets, thrust vector control, selection of rocket propulsion systems, electric propulsion, and rocket testing.

  5. NASA's Advanced solid rocket motor

    Science.gov (United States)

    Mitchell, Royce E.

    The Advanced Solid Rocket Motor (ASRM) will not only bring increased safety, reliability and performance for the Space Shuttle Booster, it will enhance overall Shuttle safety by effectively eliminating 174 failure points in the Space Shuttle Main Engine throttling system and by reducing the exposure time to aborts due to main engine loss or shutdown. In some missions, the vulnerability time to Return-to-Launch Site aborts is halved. The ASRM uses case joints which will close or remain static under the effects of motor ignition and pressurization. The case itself is constructed of the weldable steel alloy HP 9-4-0.30, having very high strength and with superior fracture toughness and stress corrosion resistance. The internal insulation is strip-wound and is free of asbestos. The nozzle employs light weight ablative parts and is some 5,000 pounds lighter than the Shuttle motor used to date. The payload performance of the ASRM-powered Shuttle is 12,000 pounds higher than that provided by the present motor. This is of particular benefit for payloads delivered to higher inclinations and/or altitudes. The ASRM facility uses state-of-the-art manufacturing techniques, including continuous propellant mixing and direct casting.

  6. NASA's Advanced solid rocket motor

    Science.gov (United States)

    Mitchell, Royce E.

    1993-01-01

    The Advanced Solid Rocket Motor (ASRM) will not only bring increased safety, reliability and performance for the Space Shuttle Booster, it will enhance overall Shuttle safety by effectively eliminating 174 failure points in the Space Shuttle Main Engine throttling system and by reducing the exposure time to aborts due to main engine loss or shutdown. In some missions, the vulnerability time to Return-to-Launch Site aborts is halved. The ASRM uses case joints which will close or remain static under the effects of motor ignition and pressurization. The case itself is constructed of the weldable steel alloy HP 9-4-0.30, having very high strength and with superior fracture toughness and stress corrosion resistance. The internal insulation is strip-wound and is free of asbestos. The nozzle employs light weight ablative parts and is some 5,000 pounds lighter than the Shuttle motor used to date. The payload performance of the ASRM-powered Shuttle is 12,000 pounds higher than that provided by the present motor. This is of particular benefit for payloads delivered to higher inclinations and/or altitudes. The ASRM facility uses state-of-the-art manufacturing techniques, including continuous propellant mixing and direct casting.

  7. Mineral Resources of the Antelope Wilderness Study Area, Nye County, Nevada

    Science.gov (United States)

    Hardyman, Richard F.; Poole, Forrest G.; Kleinhampl, Frank J.; Turner, Robert L.; Plouff, Donald; Duval, Joe S.; Johnson, Fredrick L.; Benjamin, David A.

    1987-01-01

    At the request of the U.S. Bureau of land Management, 83,100 acres of the Antelope Wilderness Study Area (NV-4)60-231/241) was studied. In this report the studied area is called the 'wilderness study area', or simply the 'study area.' No identified mineral or energy resources occur within the study area. The southern part of the area has moderate mineral resource potential for undiscovered gold and silver, and the Woodruff Formation in the southern part of the area has high resource potential for undiscovered vanadium, zinc, selenium, molybdenum, and silver (fig. 1). This assessment is based on field geochemical studies in 1984 and 1985 by the U.S. Bureau of Mines and field geochemical studies and geologic mapping by the U.S. Geological Survey in 1984 and 1985. The remainder of the study area has low resource potential for undiscovered gold, silver, lead, zinc, manganese, tin, and molybdenum. The study area also has low resource potential for undiscovered oil and gas resources. The Antelope Wilderness Study Area is about midway between Tonopah and Eureka, Nev., in the northern Hot Creek Range and southern Antelope Range of central Nevada. It is accessible by unimproved dirt roads extending 20 mi (miles) north from U.S. Highway 6 and 40 mi south from U.S. Highway 50 (fig. 2). Most of the study area consists of rugged mountainous terrain having approximately 2,600 ft (feet) of relief. The mountain range is a block tilted gently to the east and bounded on both sides by normal faults that dip steeply to moderately west and have major displacements. Most of the study area is underlain by a thick sequence of Tertiary volcanic rocks that predominantly consist of silicic ash-flow tuff, the Windous Butte Formation. Paleozoic and lower Mesozoic (see geologic time chart in appendix) marine sediments occur along the southern margin of the study area, and lower Paleozoic rocks are exposed in the northeast corner. The areas of exposed Paleozoic-Mesozoic rocks along the southern

  8. British used Congreve Rockets to Attack Napoleon

    Science.gov (United States)

    2004-01-01

    Sir William Congreve developed a rocket with a range of about 9,000 feet. The incendiary rocket used black powder, an iron case, and a 16-foot guide stick. In 1806, British used Congreve rockets to attack Napoleon's headquarters in France. In 1807, Congreve directed a rocket attack against Copenhagen.

  9. Alternate Propellant Thermal Rocket Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Alternate Propellant Thermal Rocket (APTR) is a novel concept for propulsion of space exploration or orbit transfer vehicles. APTR propulsion is provided by...

  10. Electrets used in measuring rocket exhaust effluents from the space shuttle's solid rocket booster during static test firing, DM-3

    Science.gov (United States)

    Susko, M.

    1979-01-01

    The purpose of this experimental research was to compare Marshall Space Flight Center's electrets with Thiokol's fixed flow air samplers during the Space Shuttle Solid Rocket Booster Demonstration Model-3 static test firing on October 19, 1978. The measurement of rocket exhaust effluents by Thiokol's samplers and MSFC's electrets indicated that the firing of the Solid Rocket Booster had no significant effect on the quality of the air sampled. The highest measurement by Thiokol's samplers was obtained at Plant 3 (site 11) approximately 8 km at a 113 degree heading from the static test stand. At sites 11, 12, and 5, Thiokol's fixed flow air samplers measured 0.0048, 0.00016, and 0.00012 mg/m3 of CI. Alongside the fixed flow measurements, the electret counts from X-ray spectroscopy were 685, 894, and 719 counts. After background corrections, the counts were 334, 543, and 368, or an average of 415 counts. An additional electred, E20, which was the only measurement device at a site approximately 20 km northeast from the test site where no power was available, obtained 901 counts. After background correction, the count was 550. Again this data indicate there was no measurement of significant rocket exhaust effluents at the test site.

  11. Improved hybrid rocket fuel

    Science.gov (United States)

    Dean, David L.

    1995-01-01

    McDonnell Douglas Aerospace, as part of its Independent R&D, has initiated development of a clean burning, high performance hybrid fuel for consideration as an alternative to the solid rocket thrust augmentation currently utilized by American space launch systems including Atlas, Delta, Pegasus, Space Shuttle, and Titan. It could also be used in single stage to orbit or as the only propulsion system in a new launch vehicle. Compared to solid propellants based on aluminum and ammonium perchlorate, this fuel is more environmentally benign in that it totally eliminates hydrogen chloride and aluminum oxide by products, producing only water, hydrogen, nitrogen, carbon oxides, and trace amounts of nitrogen oxides. Compared to other hybrid fuel formulations under development, this fuel is cheaper, denser, and faster burning. The specific impulse of this fuel is comparable to other hybrid fuels and is between that of solids and liquids. The fuel also requires less oxygen than similar hybrid fuels to produce maximum specific impulse, thus reducing oxygen delivery system requirements.

  12. Not just rocket science

    Energy Technology Data Exchange (ETDEWEB)

    MacAdam, S.; Anderson, R. [Celan Energy Systems, Rancho Cordova, CA (United States)

    2007-10-15

    The paper explains a different take on oxyfuel combustion. Clean Energy Systems (CES) has integrated aerospace technology into conventional power systems, creating a zero-emission power generation technology that has some advantages over other similar approaches. When using coal as a feedstock, the CES process burns syngas rather than raw coal. The process uses recycled water and steam to moderate the temperature, instead of recycled CO{sub 2}. With no air ingress, the CES process produces very pure CO{sub 2}. This makes it possible to capture over 99% of the CO{sub 2} resulting from combustion. CES uses the combustion products to drive the turbines, rather than indirectly raising steam for steam turbines, as in the oxyfuel process used by companies such as Vattenfall. The core of the process is a high-pressure oxy-combustor adapted from rocket engine technology. This combustor burns gaseous or liquid fuels with gaseous oxygen in the presence of water. Fuels include natural gas, coal or coke-derived synthesis gas, landfill and biodigester gases, glycerine solutions and oil/water emulsion. 2 figs.

  13. Wildlife mitigation and monitoring report Gunnison, Colorado, site

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    The Uranium Mill Tailings Remedial Action (UMTRA) Project is administered by the U.S. Department of Energy (DOE); its purpose is to cleanup uranium mill tailings and other contaminated material at 24 UMTRA Project sites in 10 states. This report summarizes the wildlife mitigation and monitoring program under way at the Gunnison UMTRA Project, Gunnison, Colorado. Remedial action at the Gunnison site was completed in December 1995 and is described in detail in the Gunnison completion report. The impacts of this activity were analyzed in the Gunnison environmental assessment (EA). These impacts included two important game species: the pronghorn antelope (Antilocapra americans) and sage grouse (Wentrocerus urophasianus). Haul truck traffic was predicted to limit antelope access to water sources north of the Tenderfoot Mountain haul road and that truck traffic along this and other haul roads could result in antelope road kills. Clearing land at the disposal cell, haul road and borrow site activities, and the associated human activities also were predicted to negatively impact (directly and indirectly) sage grouse breeding, nesting, loafing, and wintering habitat. As a result, an extensive mitigation and monitoring plan began in 1992. Most of the monitoring studies are complete and the results of these studies, written by different authors, appear in numerous reports. This report will: (1) Analyze existing impacts and compare them to predicted impacts. (2) Summarize mitigation measures. (3) Summarize all existing monitoring data in one report. (4) Analyze the effectiveness of the mitigation measures.

  14. Echinococcus granulosus sensu stricto (s.s.) from the critically endangered antelope Addax nasomaculatus in Tunisia.

    Science.gov (United States)

    Boufana, Belgees; Saïd, Yousra; Dhibi, Mokhtar; Craig, Philip S; Lahmar, Samia

    2015-12-01

    Echinococcus granulosus sensu lato (s.l.) is a zoonotic disease highly endemic in Tunisia. Canids including stray and semi-stray dogs, jackals and foxes are known as definitive hosts and a wide range of ungulates have been shown to harbour the metacestode hydatid stage and may serve as intermediate hosts. Fertile hydatid cysts of Echinococcus equinus and E. granulosus sensu stricto (s.s.) were recently molecularly identified for the first time from Tunisian donkeys. E. granulosus (s.s.) was also identified from wild boars in Tunisia. Here we report the confirmation of hydatid cysts caused by E. granulosus (s.s.) in the critically endangered antelope, Addax nasomaculatus in Tunisia. DNA-based molecular analysis revealed that A.nasomaculatus was infected with E. granulosus (s.s.) which had a 100% identity with the main globally distributed E. granulosus (s.s.) (EgTu01) haplotype. Cysts of Taenia hydatigena (n=33) were also observed on the liver and in the body cavity. Due to their endangered status and their relatively small numbers, it is unlikely that hydatid infection of A. nasomaculatus will form a major contribution to the epidemiology and transmission of E. granulosus in Tunisia, but infection may result in pathology, morbidity and early mortality, and may still play a role in the perpetuation of the parasite in wildlife cycles.

  15. Insights into the skeletal muscle characteristics of three southern African antelope species

    Directory of Open Access Journals (Sweden)

    Tertius Abraham Kohn

    2014-10-01

    Full Text Available Skeletal muscle fibre type, cross-sectional area (CSA, maximum enzyme capacities and fibre oxidative capacities were investigated in three southern African antelope species. Muscle samples from blesbok (Damaliscus pygargus phillipsi, mountain reedbuck (Redunca fulvorufula and greater kudu (Tragelaphus strepsiceros were collected post mortem from the Vastus lateralis and analysed for myosin heavy chain (MHC isoform content, citrate synthase (CS, 3-hydroxyacyl Co A dehydrogenase (3-HAD, phosphofructokinase (PFK, lactate dehydrogenase (LDH and creatine kinase (CK activities. Histochemistry and immunohistochemistry were performed to determine relative fibre oxidative capacity, fibre type and cross-sectional area (CSA. Type IIX fibres were the most abundant fibre type in all three species, ranging from 43 to 57%. Kudu had less type IIX fibres than mountain reedbuck and blesbok (P<0.05, values confirmed by their respective MHC isoform content. Blesbok had the smallest fibres, followed by mountain reedbuck and finally kudu (P<0.001. Overall, all three species had high oxidative and glycolytic capacities, but species differences were found. Kudu had the lowest CS activity, followed by blesbok and mountain reedbuck, but the highest PFK, LDH and CK activities. This study confirmed large variation in oxidative capacities within a single fibre type, as well as overlap between the fibre types with no distinct differences between the three species. The fibre type profile of each species is discussed and confirms some of their physical attributes and capabilities.

  16. A note on the behaviour of Four-horned Antelope Tetracerus quadricornis de Blainville, 1816 (Mammalia: Cetartiodactyla: Bovidae in lowland Nepal

    Directory of Open Access Journals (Sweden)

    Krishna Prasad Pokharel

    2015-05-01

    Full Text Available Behavioural studies provide the reasons behind habitat preferences of animals and their fitness to survive and propagate.  The Four-horned Antelope, an endangered endemic species to the Indian subcontinent was monitored at Ratamate area of Babai Valley in Bardia National Park, Nepal.  We used ad libitum sampling and focal animal sampling within the rule for continuous recording of ‘all-occurrences’ of ‘vigilance’ behaviour. We found that the Four-horned Antelope remains ‘alert and vigilant’ during 40% of its behavioural time budget when it scans the surroundings with raised head, with or without chewing. In the event of sudden threat it ‘freezes’, lying down still and hiding in the ground cover.  Therefore, maintenance of ground cover should form a regular practice in conservation management of the Four-horned Antelope

  17. Testing the global capabilities of the Antelope software suite: fast location and Mb determination of teleseismic events using the ASAIN and GSN seismic networks

    Science.gov (United States)

    Pesaresi, D.; Russi, M.; Plasencia, M.; Cravos, C.

    2009-04-01

    The Italian National Institute for Oceanography and Experimental Geophysics (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, OGS) is running the Antarctic Seismographic Argentinean Italian Network (ASAIN), made of 5 seismic stations located in the Scotia Sea region in Antarctica and in Argentina: data from these stations are transferred in real time to the OGS headquarters in Trieste (Italy) via satellite links. OGS is also running, in close cooperation with the Friuli-Venezia Giulia Civil Defense, the North East (NI) Italy seismic network, making use of the Antelope commercial software suite from BRTT as the main acquisition system. As a test to check the global capabilities of Antelope, we set up an instance of Antelope acquiring data in real time from both the regional ASAIN seismic network in Antarctica and a subset of the Global Seismic Network (GSN) funded by the Incorporated Research Institution for Seismology (IRIS). The facilities of the IRIS Data Management System, and specifically the IRIS Data Management Center, were used for real time access to waveform required in this study. Preliminary results over 1 month period indicated that about 82% of the earthquakes with magnitude M>5.0 listed in the PDE catalogue of the National Earthquake Information Center (NEIC) of the United States Geological Survey (USGS) were also correctly detected by Antelope, with an average location error of 0.05 degrees and average body wave magnitude Mb estimation error below 0.1. The average time difference between event origin time and the actual time of event determination by Antelope was of about 45': the comparison with 20', the IASPEI91 P-wave travel time for 180 degrees distance, and 25', the estimate of our test system data latency, indicate that Antelope is a serious candidate for regional and global early warning systems. Updated figures calculated over a longer period of time will be presented and discussed.

  18. Towards an adaptive management approach for the conservation of rare antelope in the Kruger National Park - outcome of a workshop held in May 2000

    Directory of Open Access Journals (Sweden)

    C.C. Grant

    2000-07-01

    Full Text Available A precipitous drop in rare antelope numbers specifically roan (Hippotragus equinis sable (Hippotragus niger and tsessebe (Damaliscus lunatus since 1986 has become one of the main concerns of management. The zebra (Equus burchelli population in the preferred habitats of these species had increased with the development of artificial waterpoints especially in the areas occupied by roan and tsessebe, and these events are hypothesised to be the main cause of the decline. Closure of artificial waterpoints resulted in moving the high-density, water-dependent zebra from the northern basalt plains, the preferred roan habitat. However, the expected responding increase in the rare antelope populations did not materialise. This lack of response over six years necessitated a critical re-evaluation of the management of rare antelope in the Kruger National Park. Subsequently, a workshop was held at Skukuza during May 2000. The options for adaptive management of the declining rare antelope populations, which was discussed at the workshop, is the subject of this manuscript. The participants felt that the removal/closure of artificial waterpoints was the most unintrusive management tool available to move high density grazers from the habitats preferred by rare antelope. Waterpoints to be closed should be carefully evaluated, and time allowed for rare antelope to respond to habitat changes. Boosting populations of roan and tsessebe by supplementing animals was seriously considered, with the proviso that it should be done under favourable circumstances. Small patch fires that could provide green grazing over extended periods were recommended. Predator control was discussed but could not obtain general support as a viable option in the Kruger National Park.

  19. Preliminary hydrogeologic assessment near the boundary of the Antelope Valley and El Mirage Valley groundwater basins, California

    Science.gov (United States)

    Stamos, Christina L.; Christensen, Allen H.; Langenheim, Victoria

    2017-07-19

    The increasing demands on groundwater for water supply in desert areas in California and the western United States have resulted in the need to better understand groundwater sources, availability, and sustainability. This is true for a 650-square-mile area that encompasses the Antelope Valley, El Mirage Valley, and Upper Mojave River Valley groundwater basins, about 50 miles northeast of Los Angeles, California, in the western part of the Mojave Desert. These basins have been adjudicated to ensure that groundwater rights are allocated according to legal judgments. In an effort to assess if the boundary between the Antelope Valley and El Mirage Valley groundwater basins could be better defined, the U.S. Geological Survey began a cooperative study in 2014 with the Mojave Water Agency to better understand the hydrogeology in the area and investigate potential controls on groundwater flow and availability, including basement topography.Recharge is sporadic and primarily from small ephemeral washes and streams that originate in the San Gabriel Mountains to the south; estimates range from about 400 to 1,940 acre-feet per year. Lateral underflow from adjacent basins has been considered minor in previous studies; underflow from the Antelope Valley to the El Mirage Valley groundwater basin has been estimated to be between 100 and 1,900 acre-feet per year. Groundwater discharge is primarily from pumping, mostly by municipal supply wells. Between October 2013 and September 2014, the municipal pumpage in the Antelope Valley and El Mirage Valley groundwater basins was reported to be about 800 and 2,080 acre-feet, respectively.This study was motivated by the results from a previously completed regional gravity study, which suggested a northeast-trending subsurface basement ridge and saddle approximately 3.5 miles west of the boundary between the Antelope Valley and El Mirage Valley groundwater basins that might influence groundwater flow. To better define potential basement

  20. [Identification and conservation assessment of suitable habitats for Tibetan antelope in the alpine desert, Qinghai-Tibet Plateau].

    Science.gov (United States)

    Zhuge, Hai-jin; Li, Xiao-wen; Zhang, Xiang; Gao, Feng; Xu, Dong-hua

    2014-12-01

    As a flagship and one of most endangered ungulates in the alpine desert of Qinghai-Tibet Plateau, the habitat conservation of Tibetan antelope (Pantholops hodgsonii) is vital to sustain its long-term population existence. In consideration of key habitat factors of the Tibetan antelope (i.e., food, topography and water source) as well as human interference factors like roads and settlements, the habitat suitability was modeled, and potential and valid suitable habitats were identified for Tibetan antelope in the alpine desert, Qinghai-Tibet Plateau. Furthermore, the conservation proportion index and conservation efficacy index were developed to facilitate the conservation assessment of three national reserves (i.e., Altun Mountain, Kekexili and Qiangtang) and their associated functional zones in the study area. The results showed that potential and valid area of suitable habitat across overall study area were 2.84 x 10(5) and 2.08 x 10(5) km2 respectively, with 16.1% of suitable habitat loss by human disturbance. At reserve level, the potential suitable habitats of Altun Mountain, Kekexili and Qiangtang were 2.01 x 10(4), 3.13 x 104 and 1.26 x 10(5) km2, which however decreased by 12.9%, 10.2% and 21.1% human disturbance respectively, indicating a prominent habitat fragmentation especially in Qiangtang National Nature Reserve (NNR). Although three NNRs had captured nearly 2/3 of the potential/valid suitable habitats with favorable conservation efficacy, there were still obvious conservation gaps outside the existing reserve network. At the functional zone level, buffer and experimental zones also showed significant conservation proportion and efficacy besides the core zone. Our research highlighted the necessity to optimize the existing re serve system by filling the conservation gaps, restructuring the functional zones and safeguarding the potential refuge habitats for those endangered ungulates in face of climate change.

  1. Remarkable vocal identity in wild-living mother and neonate saiga antelopes: a specialization for breeding in huge aggregations?

    Science.gov (United States)

    Sibiryakova, Olga V.; Volodin, Ilya A.; Frey, Roland; Zuther, Steffen; Kisebaev, Talgat B.; Salemgareev, Albert R.; Volodina, Elena V.

    2017-04-01

    Saiga antelopes Saiga tatarica tatarica give birth in large aggregations, and offspring follow the herd soon after birth. Herding is advantageous as anti-predator strategy; however, communication between mothers and neonates is strongly complicated in large aggregations. Individual series of nasal and oral contact calls of mother and neonate saiga antelopes were selected from recordings made with automated recording systems placed near the hiding neonates on the saiga breeding grounds in Northern Kazakhstan during synchronized parturitions of 30,000 calving females. We used for comparison of the acoustic structure of nasal and oral contact calls 168 nasal calls of 18 mothers, 192 oral calls of 21 mothers, 78 nasal calls of 16 neonates, and 197 oral calls of 22 neonates. In the oral calls of either mothers or neonates, formant frequencies were higher and the duration was longer than in the nasal calls, whereas fundamental frequencies did not differ between oral and nasal calls. Discriminant function analysis (DFA) based on six acoustic variables, accurately classified individual identity for 99.4% of oral calls of 18 mothers, for 89.3% of nasal calls of 18 mothers, and for 94.4% of oral calls of 18 neonates. The average value of correct classification to individual was higher in mother oral than in mother nasal calls and in mother oral calls than in neonate oral calls; no significant difference was observed between mother nasal and neonate oral calls. Variables mainly responsible for vocal identity were the fundamental frequency and the second and third formants in either mothers or neonates, and in either nasal or oral calls. The high vocal identity of mothers and neonates suggests a powerful potential for the mutual mother-offspring recognition in dense aggregations of saiga antelopes as an important component of their survival strategy.

  2. Rocket Science 101 Interactive Educational Program

    Science.gov (United States)

    Armstrong, Dennis; Funkhouse, Deborah; DiMarzio, Donald

    2007-01-01

    To better educate the public on the basic design of NASA s current mission rockets, Rocket Science 101 software has been developed as an interactive program designed to retain a user s attention and to teach about basic rocket parts. This program also has helped to expand NASA's presence on the Web regarding educating the public about the Agency s goals and accomplishments. The software was designed using Macromedia s Flash 8. It allows the user to select which type of rocket they want to learn about, interact with the basic parts, assemble the parts to create the whole rocket, and then review the basic flight profile of the rocket they have built.

  3. Rocket Science at the Nanoscale.

    Science.gov (United States)

    Li, Jinxing; Rozen, Isaac; Wang, Joseph

    2016-06-28

    Autonomous propulsion at the nanoscale represents one of the most challenging and demanding goals in nanotechnology. Over the past decade, numerous important advances in nanotechnology and material science have contributed to the creation of powerful self-propelled micro/nanomotors. In particular, micro- and nanoscale rockets (MNRs) offer impressive capabilities, including remarkable speeds, large cargo-towing forces, precise motion controls, and dynamic self-assembly, which have paved the way for designing multifunctional and intelligent nanoscale machines. These multipurpose nanoscale shuttles can propel and function in complex real-life media, actively transporting and releasing therapeutic payloads and remediation agents for diverse biomedical and environmental applications. This review discusses the challenges of designing efficient MNRs and presents an overview of their propulsion behavior, fabrication methods, potential rocket fuels, navigation strategies, practical applications, and the future prospects of rocket science and technology at the nanoscale.

  4. Low-thrust rocket trajectories

    Energy Technology Data Exchange (ETDEWEB)

    Keaton, P.W.

    1986-01-01

    The development of low-thrust propulsion systems to complement chemical propulsion systems will greatly enhance the evolution of future space programs. Two advantages of low-thrust rockets are stressed: first, in a strong gravitational field, such as occurs near the Earth, freighter missions with low-thrust engines require one-tenth as much propellant as do chemical engines. Second, in a weak gravitational field, such as occurs in the region between Venus and Mars, low-thrust rockets are faster than chemical rockets with comparable propellant mass. The purpose here is to address the physics of low-thrust trajectories and to interpret the results with two simple models. Analytic analyses are used where possible - otherwise, the results of numerical calculations are presented in graphs. The author has attempted to make this a self-contained report. 57 refs., 10 figs.

  5. Low-thrust rocket trajectories

    Energy Technology Data Exchange (ETDEWEB)

    Keaton, P.W.

    1987-03-01

    The development of low-thrust propulsion systems to complement chemical propulsion systems will greatly enhance the evolution of future space programs. Two advantages of low-thrust rockets are stressed: first, in a strong gravitational field, such as occurs near the Earth, freighter missions with low-thrust engines require one-tenth as much propellant as do chemical engines. Second, in a weak gravitational field, such as occurs in the region between Venus and Mars, low-thrust rockets are faster than chemical rockets with comparable propellant mass. The purpose here is to address the physics of low-thrust trajectories and to interpret the results with two simple models. Analytic analyses are used where possible - otherwise, the results of numerical calculations are presented in graphs. The author has attempted to make this a self-contained report.

  6. Rocket Plume Burn Hazard.

    Science.gov (United States)

    1980-01-03

    Directorate Command Projects 20 Systems Directorate 30 Sensors & Avionics Technology Directorate 40 Communication 6r Navigation Technology Directorate 50...the criterion for permissible flame contact as measured at the operational site of exposure. EXPERIENTAL PROCEDURES AND MATERIALS A synthesis of the...postulated from extrapolations of actual measurements (1) and computer analyses of combustion ingredients (W. Stone, NL, China Lake, personal communication

  7. Some typical solid propellant rocket motors

    NARCIS (Netherlands)

    Zandbergen, B.T.C.

    2013-01-01

    Typical Solid Propellant Rocket Motors (shortly referred to as Solid Rocket Motors; SRM's) are described with the purpose to form a database, which allows for comparative analysis and applications in practical SRM engineering.

  8. Integrated Composite Rocket Nozzle Extension Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop and demonstrate an Integrated Composite Rocket Nozzle Extension (ICRNE) for use in rocket thrust chambers. The ICRNE will utilize an...

  9. Some typical solid propellant rocket motors

    NARCIS (Netherlands)

    Zandbergen, B.T.C.

    2013-01-01

    Typical Solid Propellant Rocket Motors (shortly referred to as Solid Rocket Motors; SRM's) are described with the purpose to form a database, which allows for comparative analysis and applications in practical SRM engineering.

  10. Blood values of captive beira antelope (Dorcatragus megalotis) prior to and during an outbreak of fibrinous pleuropneumonia syndrome (FPPS).

    Science.gov (United States)

    Gull, Jessica M; Hebel, Christiana; Deb, Amrita; Arif, Abdi; Clauss, Marcus; Hatt, Jean-Michel; Hammer, Sven

    2014-12-01

    Currently the only captive population of beira antelope (Dorcatragus megalotis) is held at the Al Wabra Wildlife Preservation, Qatar. An outbreak of a severe respiratory disease--fibrinous pleuropneumonia syndrome, most likely caused by Mycoplasma ovipneumoniae--led to a marked population decline. Reactive systemic inflammatory (AA) amyloidosis was noted as a chronic manifestation of the disease. Blood samples had been collected for biochemistry and hematology baseline values prior to the outbreak. Population-level changes were analyzed before and during the course of the outbreak in selected blood parameters (white blood cells [WBC], blood urea nitrogen [BUN], and creatinine). The annual population WBC increased and decreased concurrently with the population size, with a significant correlation between the two measures (R = 0.92; P = 0.001). Both BUN and creatinine values were higher during the outbreak. These values peaked at the same time as mortality, which was 1 yr after the WBC peak. These changes were interpreted as the transition from an acute disease with a primary respiratory manifestation into a chronic condition where renal amyloidosis led to chronic renal failure and death. Also, elevated liver values in diseased animals were attributed to amyloidosis. Parallels to a literature report on a lung disease complex caused by M. ovipneumoniae in bighorn sheep (Ovis canadensis) were found. Trends in population-level blood values of the beira antelopes implicate amyloidosis as a significant, long-term consequence of the putative Mycoplasma infection.

  11. Summarization on variable liquid thrust rocket engines

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The technology actuality and development trend of variable thrust rocket engines at home and abroad are summarized. Key technologies of developing variable thrust rocket engines are analyzed. Development advices on developing variable thrust rocket engines that are adapted to the situation of our country are brought forward.

  12. Nuclear-Thermal Rocket Orbits Mars

    Science.gov (United States)

    1960-01-01

    Originally investigated in the 1960's by Marshall Space Flight Center plarners as part of the Nuclear Energy for Rocket Vehicle Applications (NERVA) program, nuclear-thermal rocket propulsion has been more recently considered in spacecraft designs for interplanetary human exploration. This artist's concept illustrates a nuclear-thermal rocket with an aerobrake disk as it orbits Mars.

  13. Measuring Model Rocket Engine Thrust Curves

    Science.gov (United States)

    Penn, Kim; Slaton, William V.

    2010-01-01

    This paper describes a method and setup to quickly and easily measure a model rocket engine's thrust curve using a computer data logger and force probe. Horst describes using Vernier's LabPro and force probe to measure the rocket engine's thrust curve; however, the method of attaching the rocket to the force probe is not discussed. We show how a…

  14. Measuring Model Rocket Engine Thrust Curves

    Science.gov (United States)

    Penn, Kim; Slaton, William V.

    2010-01-01

    This paper describes a method and setup to quickly and easily measure a model rocket engine's thrust curve using a computer data logger and force probe. Horst describes using Vernier's LabPro and force probe to measure the rocket engine's thrust curve; however, the method of attaching the rocket to the force probe is not discussed. We show how a…

  15. 藏羚羊PGC-1α基因编码区的克隆与分析%Molecular Cloning and Sequence Analysis of PGC-1α cDNA in Tibetan Antelope

    Institute of Scientific and Technical Information of China (English)

    马燕; 常荣; 祁玉娟; 格日力

    2012-01-01

    Total RNAs were extracted from myocardium of Tibetan Antelope {Pantholops hodgsonii) and Tibetan Sheep,both inhabiting on Tibetan Plateau (altitude 4 300 m). PGC-la coding cDNA sequences were cloned with reverse transcription polymerase chain reaction ( RT-PCR) , and the sequences were confirmed by DNA sequencing. The cloning and sequencing results confirmed that the PGC-la gene coding sequences of both Tibetan Antelope and Tibetan sheep showed above 90% identity with other species. In addition, the cloned sequences contained the RNA/DNA binding sites, RRM (RNA recognition motif) , the domains involved in the interaction with NRF-1 and MEF2C , Arg/Ser rich domain, negative regulatory domain, LXXLL motif, as well as conserved sequences like TPPTTPP and DHDYCQ, which are present in all PGC-l family members. Fourteen variable amino acid sites were identified in the functional domains mentioned above. Additionally, analysis of generic phosphorylation sites and kinase specific phosphorylation prediction sites indicated that the 329-threonine amino acid site could be phosphorylated by PKG,which may be unique to Tibetan Antelope. Secondary structures of PGC-la protein from Tibetan Antelope and Tibetan Sheep were also predicted in this study. In summary,the PGC-la gene coding regions from Tibetan antelope and Tibetan Sheep have been successfully cloned,which may provide fundamental data for further investigating high altitude adaptation related to genetics in the future.%以藏羚羊(Pantholops hodgsonii)及同海拔分布的藏系绵羊(Tibetan Sheep)的心肌组织为材料,提取总RNA,利用逆转录聚合酶链反应(RT-PCR)技术扩增出过氧化物酶体增生物激活受体γ辅激活因子-1α(PGC-1α)的基因编码区cDNA片段,与载体连接构建重组质粒,经转化、扩增培养、鉴定后测序.利用生物信息学方法分析显示,藏羚羊和藏系绵羊的PGC-1α基因编码区长度均为2 349 bp,编码797个氨基

  16. Unique nuclear thermal rocket engine

    Energy Technology Data Exchange (ETDEWEB)

    Culver, D.W. (Aerojet Propulsion Division, P.O. Box 13222, Sacramento, California 95813-6000 (United States)); Rochow, R. (Babcock Wilcox Space Nuclear Systems, P.O. Box 11165, Lynchburg, Virginia 24506-1165 (United States))

    1993-01-15

    Earlier this year Aerojet Propulsion Division (APD) introduced a new, advanced nuclear thermal rocket engine (NTRE) concept intended for manned missions to the moon and to Mars. This NTRE promises to be both shorter and lighter in weight than conventionally designed engines, because its forward flowing reactor is located within an expansion-deflection (E-D) rocket nozzle. The concept has matured during the year, and this paper discusses a nearer term version that resolves four open issues identified in the initial concept: (1)Reactor design and cooling scheme simplification while retaining a high pressure power balance option; (2)Eliminate need for a new, uncooled nozzle throat material suitable for long life application; (3)Practical provision for reactor power control; and (4)Use near term, long life turbopumps.

  17. Nanoparticles for solid rocket propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Galfetti, L [Politecnico di Milano, SPLab, Milan (Italy); De Luca, L T [Politecnico di Milano, SPLab, Milan (Italy); Severini, F [Politecnico di Milano, SPLab, Milan (Italy); Meda, L [Polimeri Europa, Istituto G Donegani, Novara (Italy); Marra, G [Polimeri Europa, Istituto G Donegani, Novara (Italy); Marchetti, M [Universita di Roma ' La Sapienza' , Dipartimento di Ingegneria Aerospaziale ed Astronautica, Rome (Italy); Regi, M [Universita di Roma ' La Sapienza' , Dipartimento di Ingegneria Aerospaziale ed Astronautica, Rome (Italy); Bellucci, S [INFN, Laboratori Nazionali di Frascati, Frascati (Italy)

    2006-08-23

    The characterization of several differently sized aluminium powders, by BET (specific surface), EM (electron microscopy), XRD (x-ray diffraction), and XPS (x-ray photoelectron spectroscopy), was performed in order to evaluate their application in solid rocket propellant compositions. These aluminium powders were used in manufacturing several laboratory composite solid rocket propellants, based on ammonium perchlorate (AP) as oxidizer and hydroxil-terminated polybutadiene (HTPB) as binder. The reference formulation was an AP/HTPB/Al composition with 68/17/15% mass fractions respectively. The ballistic characterization of the propellants, in terms of steady burning rates, shows better performance for propellant compositions employing nano-aluminium when compared to micro-aluminium. Results obtained in the pressure range 1-70 bar show that by increasing the nano-Al mass fraction or decreasing the nano-Al size, larger steady burning rates are measured with essentially the same pressure sensitivity.

  18. Unique nuclear thermal rocket engine

    Science.gov (United States)

    Culver, Donald W.; Rochow, Richard

    1993-06-01

    In January, 1992, a new, advanced nuclear thermal rocket engine (NTRE) concept intended for manned missions to the moon and to Mars was introduced (Culver, 1992). This NTRE promises to be both shorter and lighter in weight than conventionally designed engines, because its forward flowing reactor is located within an expansion-deflection rocket nozzle. The concept has matured during the year, and this paper discusses a nearer term version that resolves four open issues identified in the initial concept: (1) the reactor design and cooling scheme simplification while retaining a high pressure power balance option; (2) elimination need for a new, uncooled nozzle throat material suitable for long life application; (3) a practical provision for reactor power control; and (4) use of near-term, long-life turbopumps.

  19. Nanoparticles for solid rocket propulsion

    Science.gov (United States)

    Galfetti, L.; DeLuca, L. T.; Severini, F.; Meda, L.; Marra, G.; Marchetti, M.; Regi, M.; Bellucci, S.

    2006-08-01

    The characterization of several differently sized aluminium powders, by BET (specific surface), EM (electron microscopy), XRD (x-ray diffraction), and XPS (x-ray photoelectron spectroscopy), was performed in order to evaluate their application in solid rocket propellant compositions. These aluminium powders were used in manufacturing several laboratory composite solid rocket propellants, based on ammonium perchlorate (AP) as oxidizer and hydroxil-terminated polybutadiene (HTPB) as binder. The reference formulation was an AP/HTPB/Al composition with 68/17/15% mass fractions respectively. The ballistic characterization of the propellants, in terms of steady burning rates, shows better performance for propellant compositions employing nano-aluminium when compared to micro-aluminium. Results obtained in the pressure range 1-70 bar show that by increasing the nano-Al mass fraction or decreasing the nano-Al size, larger steady burning rates are measured with essentially the same pressure sensitivity.

  20. Environmental impact statement Space Shuttle advanced solid rocket motor program

    Science.gov (United States)

    1989-01-01

    The proposed action is design, development, testing, and evaluation of Advanced Solid Rocket Motors (ASRM) to replace the motors currently used to launch the Space Shuttle. The proposed action includes design, construction, and operation of new government-owned, contractor-operated facilities for manufacturing and testing the ASRM's. The proposed action also includes transport of propellant-filled rocket motor segments from the manufacturing facility to the testing and launch sites and the return of used and/or refurbished segments to the manufacturing site. Sites being considered for the new facilities include John C. Stennis Space Center, Hancock County, Mississippi; the Yellow Creek site in Tishomingo County, Mississippi, which is currently in the custody and control of the Tennessee Valley Authority; and John F. Kennedy Space Center, Brevard County, Florida. TVA proposes to transfer its site to the custody and control of NASA if it is the selected site. All facilities need not be located at the same site. Existing facilities which may provide support for the program include Michoud Assembly Facility, New Orleans Parish, Louisiana; and Slidell Computer Center, St. Tammany Parish, Louisiana. NASA's preferred production location is the Yellow Creek site, and the preferred test location is the Stennis Space Center.

  1. Extended temperature range rocket injector

    Science.gov (United States)

    Schneider, Steven J. (Inventor)

    1991-01-01

    A rocket injector is provided with multiple sets of manifolds for supplying propellants to injector elements. Sensors transmit the temperatures of the propellants to a suitable controller which is operably connnected to valves between these manifolds and propellant storage tanks. When cryogenic propellant temperatures are sensed, only a portion of the valves are opened to furnish propellants to some of the manifolds. When lower temperatures are sensed, additional valves are opened to furnish propellants to more of the manifolds.

  2. Mini-Rocket User Guide

    Science.gov (United States)

    2007-08-01

    Missile Research , Development, and Engineering Center and Ray Sells DESE Research , Inc. 315 Wynn Drive Huntsville, AL 35805 August 2007...with the minirock command, you are prompted for a filename: Mini-Rocket v1.01 by Ray Sells, DESE Research , Inc. Input file: - Output is printed...nancv.bucher@us.army.mil Commander, U.S. Army ARDEC Picatinny Arsenal, NJ 07806-5000 ATTN: AMSRD-AR-AIS -SA DESE Research , Inc. 3 15 Wynn Drive

  3. Optimization Problem of Multistage Rocket

    Directory of Open Access Journals (Sweden)

    V. B. Tawakley

    1972-04-01

    Full Text Available The necessary conditions for the existence of minimum of a function of initial and final values of mass, position and velocity components and time of a multistage rocket have been reviewed when the thrust levels in each stage are considered to bounded and variation in gravity with height has been taken into account. The nature of the extremal subarcs comprising the complete extremal are has been studied. A few simple examples have been given as illustrations.

  4. Ibex-associated malignant catarrhal fever-like disease in a group of bongo antelope (Tragelaphus eurycerus).

    Science.gov (United States)

    Gasper, D; Barr, B; Li, H; Taus, N; Peterson, R; Benjamin, G; Hunt, T; Pesavento, P A

    2012-05-01

    A private zoological facility experienced an outbreak of malignant catarrhal fever (MCF) in 3 bongo antelope (Tragelaphus eurycerus). All cases were periparturient bongos that presented acutely anorectic beginning ~6 weeks after being housed with a Nubian ibex. Disease quickly progressed to respiratory distress and death within 24-72 hours of onset of clinical signs. Consistent gross findings in affected bongos were pulmonary edema and small pale tan foci in the livers. Histological lesions included a nonsuppurative vasculitis in multiple tissues, which is well recognized in MCF, but additionally included necrotizing cholangiohepatitis and neutrophilic, necrotizing myocarditis. Ibex-associated viral DNA was detected by polymerase chain reaction and was identical in sequence whether derived from bongos or ibex. The sequence closely matched an MCF viral DNA fragment that had been amplified from an ibex and bongo in a previous case report.

  5. Reusable rocket engine optical condition monitoring

    Science.gov (United States)

    Wyett, L.; Maram, J.; Barkhoudarian, S.; Reinert, J.

    1987-01-01

    Plume emission spectrometry and optical leak detection are described as two new applications of optical techniques to reusable rocket engine condition monitoring. Plume spectrometry has been used with laboratory flames and reusable rocket engines to characterize both the nominal combustion spectra and anomalous spectra of contaminants burning in these plumes. Holographic interferometry has been used to identify leaks and quantify leak rates from reusable rocket engine joints and welds.

  6. The four INTA-300 rocket prototypes

    Science.gov (United States)

    Calero, J. S.

    1985-03-01

    A development history and performance capability assessment is presented for the INTA-300 'Flamenco' sounding rocket prototype specimens. The Flamenco is a two-stage solid fuel rocket, based on British sounding rocket technology, that can lift 50 km payloads to altitudes of about 300 km. The flight of the first two prototypes, in 1974 and 1975, pointed to vibration problems which reduced the achievable apogee, and the third prototype's flight was marred by a premature detonation that destroyed the rocket. The fourth Flamenco flight, however, yielded much reliable data.

  7. Demilitarization of Lance rocket motors

    Science.gov (United States)

    Sargent, Peter

    1995-02-01

    In 1992 Royal Ordnance was awarded contract by NAMSA for the demilitarization of NATO's European stock of Lance missile rocket motors. Lance is a liquid fueled surface to surface guided missile designed to give general battlefield support with either a nuclear or conventional capability at ranges of up to 130 km. The NAMSA contract required Royal Ordnance to undertake the following: (1) transportation of missiles from NATO depots in Europe to Royal Ordnance's factory at Bishopton in Scotland; (2) establishment of a dedicated demilitarization facility at Bishopton; and (3) demilitarization of live M5 and M6 training missiles by the end of 1994.

  8. The Advanced Solid Rocket Motor

    Science.gov (United States)

    Mitchell, Royce E.

    1992-08-01

    The Advanced Solid Rocket Motor will utilize improved design features and automated manufacturing methods to produce an inherently safer propulsive system for the Space Shuttle and future launch systems. This second-generation motor will also provide an additional 12,000 pounds of payload to orbit, enhancing the utility and efficiency of the Shuttle system. The new plant will feature strip-wound, asbestos-free insulation; propellant continuous mixing and casting; and extensive robotic systems. Following a series of static tests at the Stennis Space Center, MS flights are targeted to begin in early 1997.

  9. The Advanced Solid Rocket Motor

    Science.gov (United States)

    Mitchell, Royce E.

    1992-01-01

    The Advanced Solid Rocket Motor will utilize improved design features and automated manufacturing methods to produce an inherently safer propulsive system for the Space Shuttle and future launch systems. This second-generation motor will also provide an additional 12,000 pounds of payload to orbit, enhancing the utility and efficiency of the Shuttle system. The new plant will feature strip-wound, asbestos-free insulation; propellant continuous mixing and casting; and extensive robotic systems. Following a series of static tests at the Stennis Space Center, MS flights are targeted to begin in early 1997.

  10. Solid Rocket Booster-Illustration

    Science.gov (United States)

    1977-01-01

    This illustration is a cutaway of the solid rocket booster (SRB) sections with callouts. The Shuttle's two SRB's are the largest solids ever built and the first designed for refurbishment and reuse. Standing nearly 150-feet high, the twin boosters provide the majority of thrust for the first two minutes of flight, about 5.8 million pounds, augmenting the Shuttle's main propulsion system during liftoff. The major design drivers for the solid rocket motors (SRM's) were high thrust and reuse. The desired thrust was achieved by using state-of-the-art solid propellant and by using a long cylindrical motor with a specific core design that allows the propellant to burn in a carefully controlled marner. At burnout, the boosters separate from the external tank and drop by parachute to the ocean for recovery and subsequent refurbishment. The boosters are designed to survive water impact at almost 60 miles per hour, maintain flotation with minimal damage, and preclude corrosion of the hardware exposed to the harsh seawater environment. Under the project management of the Marshall Space Flight Center, the SRB's are assembled and refurbished by the United Space Boosters. The SRM's are provided by the Morton Thiokol Corporation.

  11. Reducing Thrusts In Solid-Fuel Rockets

    Science.gov (United States)

    Bement, Laurence J.

    1989-01-01

    Thrust-terminating system conceived to reduce thrust of solid-propellant rocket motor in controlled manner such that thrust loads not increased or decreased beyond predictable levels. Concept involves explosively cutting opposing venting pairs in case of rocket motor above nozzles to initiate venting of chamber and reduction of thrust. Vents sized and numbered to control amount and rate of reduction in thrust.

  12. Aerodynamics and flow characterisation of multistage rockets

    Science.gov (United States)

    Srinivas, G.; Prakash, M. V. S.

    2017-05-01

    The main objective of this paper is to conduct a systematic flow analysis on single, double and multistage rockets using ANSYS software. Today non-air breathing propulsion is increasing dramatically for the enhancement of space exploration. The rocket propulsion is playing vital role in carrying the payload to the destination. Day to day rocket aerodynamic performance and flow characterization analysis has becoming challenging task to the researchers. Taking this task as motivation a systematic literature is conducted to achieve better aerodynamic and flow characterization on various rocket models. The analyses on rocket models are very little especially in numerical side and experimental area. Each rocket stage analysis conducted for different Mach numbers and having different flow varying angle of attacks for finding the critical efficiency performance parameters like pressure, density and velocity. After successful completion of the analysis the research reveals that flow around the rocket body for Mach number 4 and 5 best suitable for designed payload. Another major objective of this paper is to bring best aerodynamics flow characterizations in both aero and mechanical features. This paper also brings feature prospectus of rocket stage technology in the field of aerodynamic design.

  13. Hybrid Rocket Experiment Station for Capstone Design

    Science.gov (United States)

    Conley, Edgar; Hull, Bethanne J.

    2012-01-01

    Portable hybrid rocket motors and test stands can be seen in many papers but none have been reported on the design or instrumentation at such a small magnitude. The design of this hybrid rocket and test stand is to be small and portable (suitcase size). This basic apparatus will be used for demonstrations in rocket propulsion. The design had to include all of the needed hardware to operate the hybrid rocket unit (with the exception of the external Oxygen tank). The design of this project includes making the correlation between the rocket's thrust and its size, the appropriate transducers (physical size, resolution, range, and cost), compatability with a laptop analog card, the ease of setup, and its portability.

  14. Integrated approach for hybrid rocket technology development

    Science.gov (United States)

    Barato, Francesco; Bellomo, Nicolas; Pavarin, Daniele

    2016-11-01

    Hybrid rocket motors tend generally to be simple from a mechanical point of view but difficult to optimize because of their complex and still not well understood cross-coupled physics. This paper addresses the previous issue presenting the integrated approach established at University of Padua to develop hybrid rocket based systems. The methodology tightly combines together system analysis and design, numerical modeling from elementary to sophisticated CFD, and experimental testing done with incremental philosophy. As an example of the approach, the paper presents the experience done in the successful development of a hybrid rocket booster designed for rocket assisted take off operations. It is thought that following the proposed approach and selecting carefully the most promising applications it is possible to finally exploit the major advantages of hybrid rocket motors as safety, simplicity, low cost and reliability.

  15. Rocket Experiment For Neutral Upwelling

    Science.gov (United States)

    Kenward, D. R.; Lessard, M.

    2015-12-01

    Observations from the CHAMP satellite from 2004 show relatively small scale heating in the thermosphere. Several different mechanisms have been proposed to explain this phenomenon. The RENU 2 rocket mission includes a suite of 14 instruments which will acquire data to help understand processes involved in neutral upwelling in the cusp. Neutral, ion, and electron measurements will be made to provide an assessment of the upwelling process. SUPERDarn measurements of large- scale Joule heating in the cusp during overflight will also be acquired. Small-scale data which could possibly be associated with Alfvén waves, will be acquired using onboard electric field measurements. In-situ measurement of precipitating electrons and all other measurements will be used in thermodynamic and electrodynamic models for comparison to the observed upwelling.

  16. Heterogeneous fuel for hybrid rocket

    Science.gov (United States)

    Stickler, David B. (Inventor)

    1996-01-01

    Heterogeneous fuel compositions suitable for use in hybrid rocket engines and solid-fuel ramjet engines, The compositions include mixtures of a continuous phase, which forms a solid matrix, and a dispersed phase permanently distributed therein. The dispersed phase or the matrix vaporizes (or melts) and disperses into the gas flow much more rapidly than the other, creating depressions, voids and bumps within and on the surface of the remaining bulk material that continuously roughen its surface, This effect substantially enhances heat transfer from the combusting gas flow to the fuel surface, producing a correspondingly high burning rate, The dispersed phase may include solid particles, entrained liquid droplets, or gas-phase voids having dimensions roughly similar to the displacement scale height of the gas-flow boundary layer generated during combustion.

  17. Draft environmental impact statement: Space Shuttle Advanced Solid Rocket Motor Program

    Science.gov (United States)

    1988-01-01

    The proposed action is design, development, testing, and evaluation of Advanced Solid Rocket Motors (ASRM) to replace the motors currently used to launch the Space Shuttle. The proposed action includes design, construction, and operation of new government-owned, contractor-operated facilities for manufacturing and testing the ASRM's. The proposed action also includes transport of propellant-filled rocket motor segments from the manufacturing facility to the testing and launch sites and the return of used and/or refurbished segments to the manufacturing site.

  18. If an antelope is a document, then a rock is data: preserving earth science samples for the future

    Science.gov (United States)

    Ramdeen, S.

    2015-12-01

    As discussed in seminal works by Briet (1951) and Buckland (1998), physical objects can be considered documents when given specific context. In the case of an antelope, in the wild it's an animal, in a zoo it's a document. It is the primary source of information, specifically when it is made an object of study. When discussing earth science data, we may think about numbers in a spreadsheet or verbal descriptions of a rock. But what about physical materials such as cores, cuttings, fossils, and other tangible objects? The most recent version of the American Geophysical Union's data position statement states data preservation and management policies should apply to both "digital data and physical objects"[1]. If an antelope is a document, than isn't a rock a form of data? Like books in a library or items in a museum, these objects require surrogates (digital or analog) that allow researchers to access and retrieve them. Once these scientific objects are acquired, researchers can process the information they contain. Unlike books, and some museum materials, most earth science objects cannot yet be completely replaced by digital surrogates. A fossil may be scanned, but the original is needed for chemical testing and ultimately for 'not yet developed' processes of scientific analysis. These objects along with their metadata or other documentation become scientific data when they are used in research. Without documentation of key information (i.e. the location where it was collected) these objects may lose their scientific value. This creates a complex situation where we must preserve the object, its metadata, and the connection between them. These factors are important as we consider the future of earth science data, our definitions of what constitutes scientific data, as well as our data preservation and management practices. This talk will discuss current initiatives within the earth science communities (EarthCube's EC3 and iSamples; USGS's data preservation program

  19. Environmental assessment of remedial action at the Gunnison Uranium Mill Tailings Site near Gunnison, Colorado. Final

    Energy Technology Data Exchange (ETDEWEB)

    1992-02-01

    The presence of contaminated uranium mill tailings adjacent to the city of Gunnison has been a local concern for many years. The following issues were identified during public meetings that were held by the DOE prior to distribution of an earlier version of this EA. Many of these issues will require mitigation. Groundwater contamination; in December 1989, a herd of 105 antelope were introduced in an area that includes the Landfill disposal site. There is concern that remedial action-related traffic in the area would result in antelope mortality. The proposed Tenderfoot Mountain haul road may restrict antelope access to their water supply; a second wildlife issue concerns the potential reduction in sage grouse use of breeding grounds (leks) and nesting habitat; the proposed Tenderfoot Mountain haul road would cross areas designated as wetlands by US Army Corps of Engineers (COE); the proposed disposal site is currently used for grazing by cattle six weeks a year in the spring. Additional concerns were stated in comments on a previous version of this EA. The proposed action is to consolidate and remove all contaminated materials associated with the Gunnison processing site to the Landfill disposal site six air miles east of Gunnison. All structures on the site (e.g., water tower, office buildings) were demolished in 1991. The debris is being stored on the site until it can be incorporated into the disposal cell at the disposal site. All contaminated materials would be trucked to the Landfill disposal site on a to-be-constructed haul road that crosses BLM-administered land.

  20. Centaur Rocket Installation in PSL #1

    Science.gov (United States)

    1962-01-01

    Centaur Rocket Installation in PSL - Propulsion Systems Laboratory #1. The RL-10 Rocket was developed by Pratt and Whitney in the late 1950's and tested at the Lewis Research Center (now known as the John H. Glenn Research Lewis Field). This power plant was the propulsion system for NASA's upper stage Centaur rocket and was significant for being the first to use liquid hydrogen and oxygen as fuel. The Centaur suffered a number of early failures, but later proved to be a very successful upper stage for numerous commercial, NASA and military payloads.

  1. Genetic structure analysis of a highly inbred captive population of the African antelope Addax nasomaculatus. Conservation and management implications.

    Science.gov (United States)

    Armstrong, E; Leizagoyen, C; Martínez, A M; González, S; Delgado, J V; Postiglioni, A

    2011-01-01

    The African antelope Addax nasomaculatus is a rare mammal at high risk of extinction, with no more than 300 individuals in the wild and 1,700 captive animals distributed in zoos around the world. In this work, we combine genetic data and genealogical information to assess the structure and genetic diversity of a captive population located at Parque Lecocq Zoo (N=27), originated from only two founders. We amplified 39 microsatellites previously described in other Artiodactyls but new to this species. Seventeen markers were polymorphic, with 2-4 alleles per locus (mean=2.71). Mean expected heterozygosity (He) per locus was between 0.050 (marker ETH3) and 0.650 (marker D5S2), with a global He of 0.43. The mean inbreeding coefficient of the population computed from pedigree records of all registered individuals (N=53) was 0.222. The mean coancestry of the population was 0.298 and F(IS) index was -0.108. These results reflect the importance of an adequate breeding management on a severely bottlenecked captive population, which would benefit by the incorporation of unrelated individuals. Thanks to the successful amplification of a large number of microsatellites commonly used in domestic bovids, this study will provide useful information for the management of this population and serve as future reference for similar studies in other captive populations of this species.

  2. Reprint of "Echinococcus granulosus sensu stricto (s.s.) from the critically endangered antelope Addax nasomaculatus in Tunisia".

    Science.gov (United States)

    Boufana, Belgees; Saïd, Yousra; Dhibi, Mokhtar; Craig, Philip S; Lahmar, Samia

    2017-01-01

    Echinococcus granulosus sensu lato (s.l.) is a zoonotic disease highly endemic in Tunisia. Canids including stray and semi-stray dogs, jackals and foxes are known as definitive hosts and a wide range of ungulates have been shown to harbour the metacestode hydatid stage and may serve as intermediate hosts. Fertile hydatid cysts of Echinococcus equinus and E. granulosus sensu stricto (s.s.) were recently molecularly identified for the first time from Tunisian donkeys. E. granulosus (s.s.) was also identified from wild boars in Tunisia. Here we report the confirmation of hydatid cysts caused by E. granulosus (s.s.) in the critically endangered antelope, Addax nasomaculatus in Tunisia. DNA-based molecular analysis revealed that A. nasomaculatus was infected with E. granulosus (s.s.) which had a 100% identity with the main globally distributed E. granulosus (s.s.) (EgTu01) haplotype. Cysts of Taenia hydatigena (n=33) were also observed on the liver and in the body cavity. Due to their endangered status and their relatively small numbers, it is unlikely that hydatid infection of A. nasomaculatus will form a major contribution to the epidemiology and transmission of E. granulosus in Tunisia, but infection may result in pathology, morbidity and early mortality, and may still play a role in the perpetuation of the parasite in wildlife cycles.

  3. Early Spin-Stabilised Rockets - the Rockets of Bergrat Heinrich Gottlob Kuhn

    Science.gov (United States)

    Fricke, H.-D.

    19th century's war rockets were at first stabilised by sticks, but these sticks produced a very uncertain flight path and it often happened that rockets changed their direction and even flew back to their firing position. So very many early inventors in Europe, America, and British-India tried to stabilise the rocket's flight in a better way. They tried fins and even rotation but they did not succeed. It is said in history that William Hale was the first who succeeded in constructing a spin stabilised (i.e. rotating) rocket which worked. But before him, in the thirties of that century, a German amateur rocket inventor succeeded as well and secretly proved his stickless rotating rockets in trials for Prussian officers and some years later officially for Saxon artillery officers. His invention was then bought by the kingdom of Saxony, but these were never use in the field because of lack of money.

  4. Hydrocarbon Rocket Technology Impact Forecasting

    Science.gov (United States)

    Stuber, Eric; Prasadh, Nishant; Edwards, Stephen; Mavris, Dimitri N.

    2012-01-01

    Forecasting method is a normative forecasting technique that allows the designer to quantify the effects of adding new technologies on a given design. This method can be used to assess and identify the necessary technological improvements needed to close the gap that exists between the current design and one that satisfies all constraints imposed on the design. The TIF methodology allows for more design knowledge to be brought to the earlier phases of the design process, making use of tools such as Quality Function Deployments, Morphological Matrices, Response Surface Methodology, and Monte Carlo Simulations.2 This increased knowledge allows for more informed decisions to be made earlier in the design process, resulting in shortened design cycle time. This paper will investigate applying the TIF method, which has been widely used in aircraft applications, to the conceptual design of a hydrocarbon rocket engine. In order to reinstate a manned presence in space, the U.S. must develop an affordable and sustainable launch capability. Hydrocarbon-fueled rockets have drawn interest from numerous major government and commercial entities because they offer a low-cost heavy-lift option that would allow for frequent launches1. However, the development of effective new hydrocarbon rockets would likely require new technologies in order to overcome certain design constraints. The use of advanced design methods, such as the TIF method, enables the designer to identify key areas in need of improvement, allowing one to dial in a proposed technology and assess its impact on the system. Through analyses such as this one, a conceptual design for a hydrocarbon-fueled vehicle that meets all imposed requirements can be achieved.

  5. 21 CFR 866.4830 - Rocket immunoelectro-phoresis equipment.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rocket immunoelectro-phoresis equipment. 866.4830... § 866.4830 Rocket immunoelectro-phoresis equipment. (a) Identification. Rocket immunoelectrophoresis... called rocket immunoelectrophoresis. In this procedure, an electric current causes the protein...

  6. Development of Kabila rocket: A radioisotope heated thermionic plasma rocket engine

    OpenAIRE

    2015-01-01

    A new type of plasma rocket engine, the Kabila rocket, using a radioisotope heated thermionic heating chamber instead of a conventional combustion chamber or catalyst bed is introduced and it achieves specific impulses similar to the ones of conventional solid and bipropellant rockets. Curium-244 is chosen as a radioisotope heat source and a thermal reductive layer is also used to obtain precise thermionic emissions. The self-sufficiency principle is applied by simultaneously heating up the e...

  7. High-speed schlieren imaging of rocket exhaust plumes

    Science.gov (United States)

    Coultas-McKenney, Caralyn; Winter, Kyle; Hargather, Michael

    2016-11-01

    Experiments are conducted to examine the exhaust of a variety of rocket engines. The rocket engines are mounted in a schlieren system to allow high-speed imaging of the engine exhaust during startup, steady state, and shutdown. A variety of rocket engines are explored including a research-scale liquid rocket engine, consumer/amateur solid rocket motors, and water bottle rockets. Comparisons of the exhaust characteristics, thrust and cost for this range of rockets is presented. The variety of nozzle designs, target functions, and propellant type provides unique variations in the schlieren imaging.

  8. Hydroxyl Tagging Velocimetry for Rocket Plumes Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A non-intrusive method for measuring velocities in a rocket exhaust is proposed in a joint effort by MetroLaser and Vanderbilt University. Hydroxyl Tagging...

  9. Fundamentals of aircraft and rocket propulsion

    CERN Document Server

    El-Sayed, Ahmed F

    2016-01-01

    This book provides a comprehensive basics-to-advanced course in an aero-thermal science vital to the design of engines for either type of craft. The text classifies engines powering aircraft and single/multi-stage rockets, and derives performance parameters for both from basic aerodynamics and thermodynamics laws. Each type of engine is analyzed for optimum performance goals, and mission-appropriate engines selection is explained. Fundamentals of Aircraft and Rocket Propulsion provides information about and analyses of: thermodynamic cycles of shaft engines (piston, turboprop, turboshaft and propfan); jet engines (pulsejet, pulse detonation engine, ramjet, scramjet, turbojet and turbofan); chemical and non-chemical rocket engines; conceptual design of modular rocket engines (combustor, nozzle and turbopumps); and conceptual design of different modules of aero-engines in their design and off-design state. Aimed at graduate and final-year undergraduate students, this textbook provides a thorough grounding in th...

  10. Magnesium Based Rockets for Martian Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In the proposed Phase II program, we will continue the development of Mg bipropellant rockets for Martian PAV applications. In Phase I, we proved the feasibility of...

  11. Magnesium Based Rockets for Martian Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop Mg rockets for Martian ascent vehicle applications. The propellant can be acquired in-situ from MgO in the Martian regolith (5.1% Mg by mass)...

  12. Advanced Vortex Hybrid Rocket Engine (AVHRE) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Orbital Technologies Corporation (ORBITEC) proposes to develop a unique Advanced Vortex Hybrid Rocket Engine (AVHRE) to achieve a highly-reliable, low-cost and...

  13. Advanced Vortex Hybrid Rocket Engine (AVHRE) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop a unique Advanced Vortex Hybrid Rocket Engine (AVHRE) to achieve a safe, highly-reliable, low-cost and uniquely versatile propulsion...

  14. Nuclear Thermal Rocket Element Environmental Simulator (NTREES)

    Science.gov (United States)

    Schoenfeld, Michael

    2009-01-01

    A detailed description of the Nuclear Thermal Rocket Element Environmental Simulator (NTREES) is presented. The contents include: 1) Design Requirements; 2) NTREES Layout; 3) Data Acquisition and Control System Schematics; 4) NTREES System Schematic; and 5) NTREES Setup.

  15. Hydroxyl Tagging Velocimetry for Rocket Plumes Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To address the need for non-intrusive sensors for rocket plume properties, we propose a laser-based velocity diagnostic that does not require seeding, works in high...

  16. Electrodynamic actuators for rocket engine valves

    Science.gov (United States)

    Fiet, O.; Doshi, D.

    1972-01-01

    Actuators, employed in acoustic loudspeakers, operate liquid rocket engine valves by replacing light paper cones with flexible metal diaphragms. Comparative analysis indicates better response time than solenoid actuators, and improved service life and reliability.

  17. Manufacturing Advanced Channel Wall Rocket Liners Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR will adapt and demonstrate a low cost flexible method of manufacturing channel wall liquid rocket nozzles and combustors, while providing developers a...

  18. Collaborative Sounding Rocket launch in Alaska and Development of Hybrid Rockets

    Science.gov (United States)

    Ono, Tomohisa; Tsutsumi, Akimasa; Ito, Toshiyuki; Kan, Yuji; Tohyama, Fumio; Nakashino, Kyouichi; Hawkins, Joseph

    Tokai University student rocket project (TSRP) was established in 1995 for a purpose of the space science and engineering hands-on education, consisting of two space programs; the one is sounding rocket experiment collaboration with University of Alaska Fairbanks and the other is development and launch of small hybrid rockets. In January of 2000 and March 2002, two collaborative sounding rockets were successfully launched at Poker Flat Research Range in Alaska. In 2001, the first Tokai hybrid rocket was successfully launched at Alaska. After that, 11 hybrid rockets were launched to the level of 180-1,000 m high at Hokkaido and Akita in Japan. Currently, Tokai students design and build all parts of the rockets. In addition, they are running the organization and development of the project under the tight budget control. This program has proven to be very effective in providing students with practical, real-engineering design experience and this program also allows students to participate in all phases of a sounding rocket mission. Also students learn scientific, engineering subjects, public affairs and system management through experiences of cooperative teamwork. In this report, we summarize the TSRP's hybrid rocket program and discuss the effectiveness of the program in terms of educational aspects.

  19. Estimation of Initial Disturbances for Rockets Based on Interactions of Rockets and Directional Tubes

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In the range of the rockets/launcher system itself, the dynamic equations for rocket and directional tube during semi-constraint period have been constructed by using Newton-Euler method. Considering the interaction of rockets and directional tubes when clearances exist, the method of estimating initial disturbances for the rocket by using vibration data of the directional tube has been given. The estimated results have been compared with the simulation results computed by the dynamic simulating software ADAMS. Results computed by the two methods are basically consistent and the computing errors do not increase with the variation of the clearance. The validity of the proposed method has been proved.

  20. Stability of Rocket Flight during Burning

    Directory of Open Access Journals (Sweden)

    T. N. Srivastava

    1967-10-01

    Full Text Available Stability of the rocket motion during burning is discussed taking into consideration gravity, aerodynamic forces and torques. Conditions for stabilizing the rocket motion are investigated. Analysis for initial and final phases of burning is given separately. Stability regions of the projected motions on two dimensional co-ordinate planes are obtained and thereby stability region of the actual motion is derived. Stability diagrams illustrate statically and dynamically stable and unstable regions.

  1. Rocket Rendezvous at Preassigned Destinations with Optimum

    Directory of Open Access Journals (Sweden)

    T. N. Srivastava

    1982-10-01

    Full Text Available The problem of rendezvous of an interceptor rocket vehicle through optimal exit path with a destination rocket vehicle at a preassigned location on the destination orbit has been investigated for non-coaxial coplanar elliptic launch and destination orbits in an inverse square gravitational field. The case, when launch and destination orbits are coplanar circular, is also discussed. In the end numerical results for rendezvous have been obtained taking Earth and Mars orbits as launch and destination orbits respectively.

  2. Computational modeling of nuclear thermal rockets

    Science.gov (United States)

    Peery, Steven D.

    1993-01-01

    The topics are presented in viewgraph form and include the following: rocket engine transient simulation (ROCETS) system; ROCETS performance simulations composed of integrated component models; ROCETS system architecture significant features; ROCETS engineering nuclear thermal rocket (NTR) modules; ROCETS system easily adapts Fortran engineering modules; ROCETS NTR reactor module; ROCETS NTR turbomachinery module; detailed reactor analysis; predicted reactor power profiles; turbine bypass impact on system; and ROCETS NTR engine simulation summary.

  3. The CODEX sounding rocket payload

    Science.gov (United States)

    Zeiger, B.; Shipley, A.; Cash, W.; Rogers, T.; Schultz, T.; McEntaffer, R.; Kaiser, M.

    2011-05-01

    We present the CODEX sounding rocket payload, a soft x-ray (0.1-1.0 keV) spectrometer designed to observe diffuse high-surface brightness astronomical sources. The payload is composed of two modules, each with a 3.25° x 3.25° field of view defined by a stack of wire grids that block light not coming to a 3.0 m focus and admit only nearly-collimated light onto an array of 67 diffraction gratings in an off-plane mount. After a 2.0 m throw, the spectrum is detected by offset large-format gaseous electron multiplier (GEM) detectors. CODEX will target the Vela supernova remnant later this year to measure the temperature and abundances and to determine the contributions of various soft x-ray emission mechanisms to the remnant's energy budget; resulting spectra will have resolution (E/▵E) ranging from 50 to 100 across the band. CODEX is the third-generation of similar payloads from the University of Colorado, with an increased bandpass, higher throughput, and a more robust mechanical structure than its predecessors.

  4. NASA Space Rocket Logistics Challenges

    Science.gov (United States)

    Neeley, James R.; Jones, James V.; Watson, Michael D.; Bramon, Christopher J.; Inman, Sharon K.; Tuttle, Loraine

    2014-01-01

    The Space Launch System (SLS) is the new NASA heavy lift launch vehicle and is scheduled for its first mission in 2017. The goal of the first mission, which will be uncrewed, is to demonstrate the integrated system performance of the SLS rocket and spacecraft before a crewed flight in 2021. SLS has many of the same logistics challenges as any other large scale program. Common logistics concerns for SLS include integration of discreet programs geographically separated, multiple prime contractors with distinct and different goals, schedule pressures and funding constraints. However, SLS also faces unique challenges. The new program is a confluence of new hardware and heritage, with heritage hardware constituting seventy-five percent of the program. This unique approach to design makes logistics concerns such as commonality especially problematic. Additionally, a very low manifest rate of one flight every four years makes logistics comparatively expensive. That, along with the SLS architecture being developed using a block upgrade evolutionary approach, exacerbates long-range planning for supportability considerations. These common and unique logistics challenges must be clearly identified and tackled to allow SLS to have a successful program. This paper will address the common and unique challenges facing the SLS programs, along with the analysis and decisions the NASA Logistics engineers are making to mitigate the threats posed by each.

  5. Environmentally compatible solid rocket propellants

    Science.gov (United States)

    Jacox, James L.; Bradford, Daniel J.

    1995-01-01

    Hercules' clean propellant development research is exploring three major types of clean propellant: (1) chloride-free formulations (no chlorine containing ingredients), being developed on the Clean Propellant Development and Demonstration (CPDD) contract sponsored by Phillips Laboratory, Edwards Air Force Base, CA; (2) low HCl scavenged formulations (HCl-scavenger added to propellant oxidized with ammonium perchlorate (AP)); and (3) low HCl formulations oxidized with a combination of AN and AP (with or without an HCl scavenger) to provide a significant reduction (relative to current solid rocket boosters) in exhaust HCl. These propellants provide performance approaching that of current systems, with less than 2 percent HCl in the exhaust, a significant reduction (greater than or equal to 70 percent) in exhaust HCl levels. Excellent processing, safety, and mechanical properties were achieved using only readily available, low cost ingredients. Two formulations, a sodium nitrate (NaNO3) scavenged HTPB and a chloride-free hydroxy terminated polyether (HTPE) propellant, were characterized for ballistic, mechanical, and rheological properties. In addition, the hazards properties were demonstrated to provide two families of class 1.3, 'zero-card' propellants. Further characterization is planned which includes demonstration of ballistic tailorability in subscale (one to 70 pound) motors over the range of burn rates required for retrofit into current Hercules space booster designs (Titan 4 SRMU and Delta 2 GEM).

  6. Nitrous Oxide/Paraffin Hybrid Rocket Engines

    Science.gov (United States)

    Zubrin, Robert; Snyder, Gary

    2010-01-01

    Nitrous oxide/paraffin (N2OP) hybrid rocket engines have been invented as alternatives to other rocket engines especially those that burn granular, rubbery solid fuels consisting largely of hydroxyl- terminated polybutadiene (HTPB). Originally intended for use in launching spacecraft, these engines would also be suitable for terrestrial use in rocket-assisted takeoff of small airplanes. The main novel features of these engines are (1) the use of reinforced paraffin as the fuel and (2) the use of nitrous oxide as the oxidizer. Hybrid (solid-fuel/fluid-oxidizer) rocket engines offer advantages of safety and simplicity over fluid-bipropellant (fluid-fuel/fluid-oxidizer) rocket en - gines, but the thrusts of HTPB-based hybrid rocket engines are limited by the low regression rates of the fuel grains. Paraffin used as a solid fuel has a regression rate about 4 times that of HTPB, but pure paraffin fuel grains soften when heated; hence, paraffin fuel grains can, potentially, slump during firing. In a hybrid engine of the present type, the paraffin is molded into a 3-volume-percent graphite sponge or similar carbon matrix, which supports the paraffin against slumping during firing. In addition, because the carbon matrix material burns along with the paraffin, engine performance is not appreciably degraded by use of the matrix.

  7. A3 Subscale Rocket Hot Fire Testing

    Science.gov (United States)

    Saunders, G. P.; Yen, J.

    2009-01-01

    This paper gives a description of the methodology and results of J2-X Subscale Simulator (JSS) hot fire testing supporting the A3 Subscale Diffuser Test (SDT) project at the E3 test facility at Stennis Space Center, MS (SSC). The A3 subscale diffuser is a geometrically accurate scale model of the A3 altitude simulating rocket test facility. This paper focuses on the methods used to operate the facility and obtain the data to support the aerodynamic verification of the A3 rocket diffuser design and experimental data quantifying the heat flux throughout the facility. The JSS was operated at both 80% and 100% power levels and at gimbal angle from 0 to 7 degrees to verify the simulated altitude produced by the rocket-rocket diffuser combination. This was done with various secondary GN purge loads to quantify the pumping performance of the rocket diffuser. Also, special tests were conducted to obtain detailed heat flux measurements in the rocket diffuser at various gimbal angles and in the facility elbow where the flow turns from vertical to horizontal upstream of the 2nd stage steam ejector.

  8. Advanced Solid Rocket Launcher and Its Evolution

    Science.gov (United States)

    Morita, Yasuhiro; Imoto, Takayuki; Habu, Hiroto; Ohtsuka, Hirohito; Hori, Keiichi; Koreki, Takemasa; Fukuchi, Apollo; Uekusa, Yasuyuki; Akiba, Ryojiro

    The research on next generation solid propellant rockets is actively underway in various spectra. JAXA is developing the Advanced Solid Rocket (ASR) as a successor to the M-V launch vehicle, which was utilized over past ten years for space science programs including planetary missions. ASR is a result of the development of the next generation technology including a highly intelligent autonomous check-out system, which is connected to not only the solid rocket but also future transportation systems. It is expected to improve the efficiency of the launch system and double the cost performance. Far beyond this effort, the passion of the volunteers among the industry-government-academia cooperation has been united to establish the society of the freewheeling thinking “Next generation Solid Rocket Society (NSRS)”. It aims at a larger revolution than what the ASR provides so that the order of the cost performance is further improved. A study of the Low melting temperature Thermoplastic Propellant (LTP) is now at the experimental stage, which is expected to reform the manufacturing process of the solid rocket propellant and lead to a significant increase in cost performance. This paper indicates the direction of the big flow towards the next generation solid-propellant rockets: the concept of the intelligent ASR under development; and the innovation behind LTP.

  9. [Identification of ecological corridors for Tibetan antelope and assessment of their human disturbances in the alpine desert of Qinghai-Tibet Plateau].

    Science.gov (United States)

    Zhuge, Hai-jin; Lin, Dan-qi; Li, Xiao-wen

    2015-08-01

    The alpine desert of Qinghai-Tibet Plateau (QTP) provides the largest habitats for those endangered ungulates (e.g., Tibetan antelope, Tibetan Kiang and wild yak) on the earth. However, human disturbance especially infrastructure constructions (e.g., railway & highway) has increasingly fragmented the habitats of those endangered ungulates by disturbing and interrupting their ecological corridors for their seasonal migration. Aiming at identifying the potential ecological corridors for Tibetan antelope, a GIS-based model-Linkage Mapper was used to model and detect the potential ecological corridors of Tibetan antelope based on the principle of least cost path. Three categories of ecological corridors, i. e., closed (inside reserves), linking (linking the reserves) and open (starting from reserve but ending outside) corridors were distinguished by their spatial interactions with existing major national nature reserves (i.e., Altun, Kekexili and Qiangtang NNRs) in the alpine desert of QTP, and their spatial patterns, conservation status associated with human disturbance were also examined. Although our research indicated a general ecological integration of both habitats and ecological corridors in the alpine desert ecosystem, increasing human disturbance should not be ignored, which particularly partially undermined the functioning of those ecological corridors linking the nature reserves. Considering disadvantages of prevailing separate administrative structure of nature reserve on the effective conservation of ecological corridors for those endangered ungulates, a coordinative conservation network among these major national nature reserves should be established to ensure the unified trans-boundary conservation efforts and to enhance its overall conservation efficacy by sharing information, knowledge and optimizing conservation resources.

  10. Rockets and People. Volume 1

    Science.gov (United States)

    Chertok, Boris E; Siddiqi, Asif A. (Editor)

    2005-01-01

    Much has been written in the West on the history of the Soviet space program but few Westerners have read direct first-hand accounts of the men and women who were behind the many Russian accomplishments in exploring space.The memoirs of Academician Boris Chertok, translated from the original Russian, fills that gap.Chertok began his career as an electrician in 1930 at an aviation factory near Moscow.Twenty-seven years later, he became deputy to the founding figure of the Soviet space program, the mysterious Chief Designer Sergey Korolev. Chertok s sixty-year-long career and the many successes and failures of the Soviet space program constitute the core of his memoirs, Rockets and People. These writings are spread over four volumes. This is volume I. Academician Chertok not only describes and remembers, but also elicits and extracts profound insights from an epic story about a society s quest to explore the cosmos. In Volume 1, Chertok describes his early years as an engineer and ends with the mission to Germany after the end of World War II when the Soviets captured Nazi missile technology and expertise. Volume 2 takes up the story with the development of the world s first intercontinental ballistic missile ICBM) and ends with the launch of Sputnik and the early Moon probes. In Volume 3, Chertok recollects the great successes of the Soviet space program in the 1960s including the launch of the world s first space voyager Yuriy Gagarin as well as many events connected with the Cold War. Finally, in Volume 4, Chertok meditates at length on the massive Soviet lunar project designed to beat the Americans to the Moon in the 1960s, ending with his remembrances of the Energiya-Buran project.

  11. Exploring the Solid Rocket Boosters and Properties of Matter

    Science.gov (United States)

    Moffett, Amy

    2007-01-01

    I worked for the United Space Alliance, LLC (USA) with the Solid Rocket Booster (SRB) Materials and Process engineers (M&P). I was assigned a project in which I needed to research and collect chemical and physical properties information, material safety data sheets (MSDS), and other product information from the vendor's websites and existing "inhouse" files for a select group of materials used in building and refurbishing the SRBs. This information was then compiled in a report that summarized the information collected. My work site was at the Kennedy Space Center (KSC). This allowed for many opportunities to visit and tour sites operated by NASA, by USA, and by the Air Force. This included the vehicle assembly building (VAB), orbital processing facilities (OPF), the crawler with the mobile launch pad (MLP), and the SRB assembly and refurbishment facility (ARF), to name a few. In addition, the launch, of STS- 117 took place within the first week of employment allowing a day by day following of that mission including post flight operations for the SRBs. Two Delta II rockets were also launched during these 7 weeks. The sights were incredible and the operations witnessed were amazing. I learned so many things I never knew about the entire program and the shuttle itself. The entire experience, especially my work with the SRB materials, inspired my plan for implementation into the classroom.

  12. Knee-clicks and visual traits indicate fighting ability in eland antelopes: multiple messages and back-up signals

    Directory of Open Access Journals (Sweden)

    Dabelsteen Torben

    2008-11-01

    Full Text Available Abstract Background Given the costs of signalling, why do males often advertise their fighting ability to rivals using several signals rather than just one? Multiple signalling theories have developed largely in studies of sexual signals, and less is known about their applicability to intra-sexual communication. We here investigate the evolutionary basis for the intricate agonistic signalling system in eland antelopes, paying particular attention to the evolutionary phenomenon of loud knee-clicking. Results A principal components analysis separated seven male traits into three groups. The dominant frequency of the knee-clicking sound honestly indicated body size, a main determinant of fighting ability. In contrast, the dewlap size increased with estimated age rather than body size, suggesting that, by magnifying the silhouette of older bulls disproportionately, the dewlap acts as an indicator of age-related traits such as fighting experience. Facemask darkness, frontal hairbrush size and body greyness aligned with a third underlying variable, presumed to be androgen-related aggression. A longitudinal study provided independent support of these findings. Conclusion The results show that the multiple agonistic signals in eland reflect three separate components of fighting ability: (1 body size, (2 age and (3 presumably androgen-related aggression, which is reflected in three backup signals. The study highlights how complex agonistic signalling systems can evolve through the simultaneous action of several selective forces, each of which favours multiple signals. Specifically, loud knee-clicking is discovered to be an honest signal of body size, providing an exceptional example of the potential for non-vocal acoustic communication in mammals.

  13. Feed consumption, diet digestibility and mineral utilization in captive blackbuck (Antelope cervicapra) fed different levels of concentrates.

    Science.gov (United States)

    Das, A; Katole, S; Choubey, M; Gupta, S P; Saini, M; Kumar, V; Swarup, D

    2013-02-01

    A feeding trial was conducted to know the level of concentrates in the diet of Antelope cervicapra at which diet digestibility and mineral utilization were optimum. Fifteen blackbucks (25-33 kg BW) were distributed into three groups of five each. Fresh oat (Avena sativa) and berseem (Trifolium alexandrinum) fodders were offered ad libitum to all the animals. In addition, animals in groups II and III received concentrate mixture at the rate of 0.5 and 1% of BW, whereas animals in group I received no concentrates. As the level of concentrates increased, consumption of fodder decreased resulting in decreased consumption of neutral detergent fibre (NDFom), acid detergent fibre (ADFom), hemicellulose and cellulose. However, overall total dry matter (DM) and organic matter (OM) intake was not significantly different between the groups. Digestibility of DM, OM and gross energy (GE) increased while that of NDFom and ADFom decreased with increased level of concentrates in the diet. Intake of P, Zn, Cu and Mn increased with increased level of concentrate supplementation; however, consumption of Ca and Fe followed the reverse trend. Absorption of P and Zn increased with increased level of concentrate supplementation. Serum concentration of Zn increased when concentrate was supplemented at the rate of 0.5% BW beyond which there was no further improvement. Increasing the level of concentrates in the diet was resulted in increased serum glucose and cholesterol levels. Forage-only diet was inadequate in supply of energy, P and zinc. Supplementation of concentrates at the rate of 0.5% BW was able to meet the requirement of these nutrients. Supplementation at the rate of 1% BW supplied energy and P in excess of requirement. It was concluded that the feeding of concentrates to the captive blackbuck fed forage-based diets should be restricted to 0.5% of BW.

  14. Monitoring the endangered population of the antelope Kobus leche smithemani (Artiodactyla: Bovidae, in the Bangweulu ecosystem, Zambia

    Directory of Open Access Journals (Sweden)

    Victor M. Siamudaala

    2012-12-01

    Full Text Available Black lechwe (Kobus leche smithemani is a semi-aquatic medium sized antelope currently enlisted on the IUCN red list of endangered species and is only endemic to the Bangweulu basin of Zambia. Its population has significantly decreased due to floods that took place during the period 1930-1940 from over 250 000-15 000 leading the Zambian government to gazette all habitats of Black lechwe into state protected areas, and to establish urgent management strategies needed to save the remaining population from extinction. Using retrospective data, our findings show that the population has increased from 15 000 animals in 1954 to 55 632 in 2009. The current population is estimated at 34.77% (55 632/160 000 of the carrying capacity of the Bangweulu basin. Although the Black lechwe is one of the 42 species offered for consumptive utilization by the Zambia Wildlife Authority (ZAWA, only 0.12% and 0.08% of the current stock was offered for safari and resident hunting annually for the period 2005-2009, respectively. Annual quota utilization were estimated at 67% (n=37 and 81% (n=37 for safari and resident hunting, respectively. Hence, overall income obtained from utilization of Black lechwe is very low accounting for only 2.1% of the total revenue earned from wildlife utilization. Although the current population trend is showing a unit increase of 639 animals per year, it is still far below levels ideal for the lucrative utilization. In this study, we demonstrate that adverse ecological changes on wildlife species, can lead to their vulnerability and danger of extinction, and that their recovery to full carrying capacity may demand a considerable amount of time

  15. Monitoring the endangered population of the antelope Kobus leche smithemani (Artiodactyla: Bovidae), in the Bangweulu Ecosystem, Zambia.

    Science.gov (United States)

    Siamudaala, Victor M; Munyeme, Musso; Matandiko, Wigganson; Muma, John B; Munang'andu, Hetron M

    2012-12-01

    Black lechwe (Kobus leche smithemani) is a semi-aquatic medium sized antelope currently enlisted on the IUCN red list of endangered species and is only endemic to the Bangweulu basin of Zambia. Its population has significantly decreased due to floods that took place during the period 1930-1940 from over 250 000-15000 leading the Zambian government to gazette all habitats of Black lechwe into state protected areas, and to establish urgent management strategies needed to save the remaining population from extinction. Using retrospective data, our findings show that the population has increased from 15000 animals in 1954 to 55 632 in 2009. The current population is estimated at 34.77% (55 632/160 000) of the carrying capacity of the Bangweulu basin. Although the Black lechwe is one of the 42 species offered for consumptive utilization by the Zambia Wildlife Authority (ZAWA), only 0.12% and 0.08% of the current stock was offered for safari and resident hunting annually for the period 2005-2009, respectively. Annual quota utilization were estimated at 67% (n=37) and 81% (n=37) for safari and resident hunting, respectively. Hence, overall income obtained from utilization of Black lechwe is very low accounting for only 2.1% of the total revenue earned from wildlife utilization. Although the current population trend is showing a unit increase of 639 animals per year, it is still far below levels ideal for the lucrative utilization. In this study, we demonstrate that adverse ecological changes on wildlife species, can lead to their vulnerability and danger of extinction, and that their recovery to full carrying capacity may demand a considerable amount of time.

  16. Spatial and temporal turbulence evolution as inferred from the WADIS sounding rocket project

    Science.gov (United States)

    Strelnikov, Boris; Asmus, Heiner; Latteck, Ralph; Strelnikova, Irina; Lübken, Franz-Josef; Baumgarten, Gerd; Hildebrand, Jens; Höffner, Josef; Wörl, Raimund; Rapp, Markus; Friedrich, Martin

    2016-04-01

    The WADIS project (Wave propagation and dissipation in the middle atmosphere: energy budget and distribution of trace constituents) aimed at studying waves, their dissipation, and effects on trace constituents. The project comprised two sounding rocket campaigns conducted at the Andøya Space Center (69 °N, 16 °E). One sounding rocket was launched in summer 2013 and one in winter 2015. The WADIS-1 sounding rocket was launched on 27 of June 2013 into Polar Mesosphere Summer Echo (PMSE). Ground based PMSE observations were conducted using the MAARSY VHF- and the EISCAT-Tromsø radars. IAP RMR-lidar observed NLC colocated with PMSE. The WADIS-2 sounding rocket was launched on 5 of March of 2015 and had the same instrumentation on board. ALOMAR RMR- and IAP Fe-lidars and SAURA-MF radar measured mesospheric temperatures and winds throughout the launch window. In-situ measurements delivered high resolution altitude-profiles of neutral and plasma densities, neutral air temperature and turbulence. Extensive turbulence measurements were conducted employing different techniques. In-situ measurements were done on both upleg and downleg, implying that two profiles of each quantity were near simultaneously measured with high altitude resolution at ˜30 km horizontal distance. The measurements with MAARSY cover both up- and downleg parts of the rocket trajectory and the EISCAT-Tromsø radar is located 100 km away of the launch site. We discuss these turbulence measurements and its spatial and time evolution.

  17. Web-based tools for real-time assessment of Earthscope's Transportable Array state-of- health: integration of the Antelope Real Time System, RRDtool, AJAX and PHP

    Science.gov (United States)

    Newman, R. L.; Lindquist, K. G.; Vernon, F. L.; Davis, G. A.; Eakins, J.; Astiz, L.

    2007-05-01

    Over the past three years the Array Network Facility (ANF) has developed a robust, extensible web-based toolkit for monitoring the state-of-health of Earthscope's Transportable Array. The tools are constructed within a framework of the Antelope Real Time System (ARTS) and the Antelope interface to the PHP Hypertext Processor (PHP), an inline scripting language. Exporting data from Datascope databases and Object Ring Buffer (ORB) packets into XML allows comprehensive client-side interaction via Asynchronous Javascript And XML (AJAX) calls. Navigating and displaying the resultant XML Document Object Model (DOM) trees are done using eXtensible Stylesheet Language Transformation (XSLT) and PHP's built-in DOM classes. Tools include regional and individual station and event maps, state-of-health statistics, waveform plots, and datalogger monitoring. Combined with real-time graphing of state-of-health parameters from status ORB packets using Round Robin Database Tool (RRDtool), this toolkit allows analysts, station engineers, scientists, and the general public to view, assess, interact with, and download data collected from the 250+ stations in the Transportable Array seismic network. Tools are available at the Array Network Facility website, http:anf.ucsd.edu.

  18. Helminth parasites of the Kafue lechwe antelope ( Kobus leche kafuensis): a potential source of infection to domestic animals in the Kafue wetlands of Zambia.

    Science.gov (United States)

    Phiri, A M; Chota, A; Muma, J B; Munyeme, M; Sikasunge, C S

    2011-03-01

    The Kafue lechwe antelope (Kobus leche kafuensis), a medium-sized, semi-aquatic antelope, grazes extensively on pastures accessed by livestock in and around Lochinvar and Blue Lagoon national parks in the Kafue wetlands of Zambia. This interaction has a potential for bi-modal transmission of a wide range of parasitic helminths between lechwe and domestic ruminants. A survey was conducted to investigate the status of helminths in the Kafue lechwe during the 2008 (July-December) hunting season, involving 65 animals hunted under special research licences. Worm identification was based on morphological features using standard identification keys. Eleven different types of helminths were identified in the animals studied; namely, Oesophagostomum, Bunostomum, Cooperia, Dictyocaulus, Marshallagia, Stilesia, Setaria, Trichuris, Fasciola, amphistomes and Schistosoma. Amphistomes (100%) and Oesophagostomum (60.9%) were the most common while Fasciola (7.8%) and Stilesia (1.6%) were the least of the identified helminths. There was no evidence that helminths, at intensities observed, adversely affected the health of the lechwe. The degree of worm infection was observed to vary between the two study areas, with Blue Lagoon recording higher infection levels compared to Lochinvar. The host range of many of the helminths found in the Kafue lechwe is broad and could serve as a potentially stable source of infection to domestic animals such as goats and cattle. Therefore, issues concerning livestock management and conservation may arise.

  19. Regenerative Cooling for Liquid Rocket Engines

    Institute of Scientific and Technical Information of China (English)

    QiFeng

    1995-01-01

    Heat transfer in the thrust chamber is of great importance in the design of liquid propellant rocket engines.Regenerative cooling is and advanced method which can ensure not only the proper running but also higher performance of a rocket engine.The theoretical model is complicated,it relates to fluid bynamics,heat transfer,combustion.etc…,In this paper,a regenerative cooling model is presented.Effects such as radiation,heat transfer to environment,variable thermal properties and coking are included in the model.This model can be applied to all kinds of liquid propellant rocket engines as well as similar constructions.The modularized computer code is completed in the work.

  20. Metallic Hydrogen: A Game Changing Rocket Propellant

    Science.gov (United States)

    Silvera, Isaac F.

    2016-01-01

    The objective of this research is to produce metallic hydrogen in the laboratory using an innovative approach, and to study its metastability properties. Current theoretical and experimental considerations expect that extremely high pressures of order 4-6 megabar are required to transform molecular hydrogen to the metallic phase. When metallic hydrogen is produced in the laboratory it will be extremely important to determine if it is metastable at modest temperatures, i.e. remains metallic when the pressure is released. Then it could be used as the most powerful chemical rocket fuel that exists and revolutionize rocketry, allowing single-stage rockets to enter orbit and chemically fueled rockets to explore our solar system.

  1. Laser-fusion rocket for interplanetary propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, R.A.

    1983-09-27

    A rocket powered by fusion microexplosions is well suited for quick interplanetary travel. Fusion pellets are sequentially injected into a magnetic thrust chamber. There, focused energy from a fusion Driver is used to implode and ignite them. Upon exploding, the plasma debris expands into the surrounding magnetic field and is redirected by it, producing thrust. This paper discusses the desired features and operation of the fusion pellet, its Driver, and magnetic thrust chamber. A rocket design is presented which uses slightly tritium-enriched deuterium as the fusion fuel, a high temperature KrF laser as the Driver, and a thrust chamber consisting of a single superconducting current loop protected from the pellet by a radiation shield. This rocket can be operated with a power-to-mass ratio of 110 W gm/sup -1/, which permits missions ranging from occasional 9 day VIP service to Mars, to routine 1 year, 1500 ton, Plutonian cargo runs.

  2. The Norwegian Sounding Rocket and Balloon Program

    Science.gov (United States)

    Skatteboe, Rolf

    2001-08-01

    The status and recent developments of the Norwegian Sounding Rocket and Balloon Program are presented with focus on national activities and recent achievements. The main part of the Norwegian program is sounding rocket launches conducted by Andøya Rocket Range from the launch facilities on Andøya and at Svalbard. For the majority of the programs, the scientific goal is investigation of processes in the middle and upper atmosphere. The in situ measurements are supplemented by a large number of ground-based support instruments located at the ALOMAR Observatory. The ongoing and planned projects are described and the highlights of the latest completed projects are given. The scientific program for the period 2001-2003 will be reviewed. Several new programs have been started to improve the services available to the international science comunity. The Hotel Payload project and MiniDusty are important examples that will be introduced in the paper. Available space related infrastructure is summarized.

  3. Atmospheric scavenging of solid rocket exhaust effluents

    Science.gov (United States)

    Fenton, D. L.; Purcell, R. Y.

    1978-01-01

    Solid propellant rocket exhaust was directly utilized to ascertain raindrop scavenging rates for hydrogen chloride. Two chambers were used to conduct the experiments; a large, rigid walled, spherical chamber stored the exhaust constituents, while the smaller chamber housing all the experiments was charged as required with rocket exhaust HCl. Surface uptake experiments demonstrated an HCl concentration dependence for distilled water. Sea water and brackish water HCl uptake was below the detection limit of the chlorine-ion analysis technique used. Plant life HCl uptake experiments were limited to corn and soybeans. Plant age effectively correlated the HCl uptake data. Metallic corrosion was not significant for single 20 minute exposures to the exhaust HCl under varying relative humidity. Characterization of the aluminum oxide particles substantiated the similarity between the constituents of the small scale rocket and the full size vehicles.

  4. Additive Manufacturing for Affordable Rocket Engines

    Science.gov (United States)

    West, Brian; Robertson, Elizabeth; Osborne, Robin; Calvert, Marty

    2016-01-01

    Additive manufacturing (also known as 3D printing) technology has the potential to drastically reduce costs and lead times associated with the development of complex liquid rocket engine systems. NASA is using 3D printing to manufacture rocket engine components including augmented spark igniters, injectors, turbopumps, and valves. NASA is advancing the process to certify these components for flight. Success Story: MSFC has been developing rocket 3D-printing technology using the Selective Laser Melting (SLM) process. Over the last several years, NASA has built and tested several injectors and combustion chambers. Recently, MSFC has 3D printed an augmented spark igniter for potential use the RS-25 engines that will be used on the Space Launch System. The new design is expected to reduce the cost of the igniter by a factor of four. MSFC has also 3D printed and tested a liquid hydrogen turbopump for potential use on an Upper Stage Engine. Additive manufacturing of the turbopump resulted in a 45% part count reduction. To understanding how the 3D printed parts perform and to certify them for flight, MSFC built a breadboard liquid rocket engine using additive manufactured components including injectors, turbomachinery, and valves. The liquid rocket engine was tested seven times in 2016 using liquid oxygen and liquid hydrogen. In addition to exposing the hardware to harsh environments, engineers learned to design for the new manufacturing technique, taking advantage of its capabilities and gaining awareness of its limitations. Benefit: The 3D-printing technology promises reduced cost and schedule for rocket engines. Cost is a function of complexity, and the most complicated features provide the largest opportunities for cost reductions. This is especially true where brazes or welds can be eliminated. The drastic reduction in part count achievable with 3D printing creates a waterfall effect that reduces the number of processes and drawings, decreases the amount of touch

  5. CODEX sounding rocket wire grid collimator design

    Science.gov (United States)

    Shipley, Ann; Zeiger, Ben; Rogers, Thomas

    2011-05-01

    CODEX is a sounding rocket payload designed to operate in the soft x-ray (0.1-1.0 kV) regime. The instrument has a 3.25 degree square field of view that uses a one meter long wire grid collimator to create a beam that converges to a line in the focal plane. Wire grid collimator performance is directly correlated to the geometric accuracy of actual grid features and their relative locations. Utilizing a strategic combination of manufacturing and assembly techniques, this design is engineered for precision within the confines of a typical rocket budget. Expected resilience of the collimator under flight conditions is predicted by mechanical analysis.

  6. The XQC microcalorimeter sounding rocket: a stable LTD platform 30 seconds after rocket motor burnout

    Energy Technology Data Exchange (ETDEWEB)

    Porter, F.S. E-mail: frederick.s.porter@gsfc.nasa.gov; Almy, R.; Apodaca, E.; Figueroa-Feliciano, E.; Galeazzi, M.; Kelley, R.; McCammon, D.; Stahle, C.K.; Szymkowiak, A.E.; Sanders, W.T

    2000-04-07

    The XQC microcalorimeter sounding rocket experiment is designed to provide a stable thermal environment for an LTD detector system within 30 s of the burnout of its second stage rocket motor. The detector system used for this instrument is a 36-pixel microcalorimeter array operated at 60 mK with a single-stage adiabatic demagnetization refrigerator (ADR). The ADR is mounted on a space-pumped liquid helium tank with vapor cooled shields which is vibration isolated from the rocket structure. We present here some of the design and performance details of this mature LTD instrument, which has just completed its third suborbital flight.

  7. Cusp Alfven and Plasma Electrodynamics Rocket (CAPER) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Launch a single rocket from Andoya Rocket Range into an active cusp event. Observe electric and magnetic fields, HF waves, electron and ion distributions and...

  8. Hydrocarbon Rocket Engine Plume Imaging with Laser Induced Incandescence Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA/ Marshall Space Flight Center (MSFC) needs sensors that can be operated on rocket engine plume environments to improve NASA/SSC rocket engine performance. In...

  9. A study of early korean rockets (1377-1600)

    Science.gov (United States)

    Chae, Yeon Seok

    The first Korean rocket was fired between 1377 and 1389 and began the Korean development of rockets as a tactical weapon. Although, Korea had successfully demonstrated the use of rockets as firearms in the fifteenth century, there had been no effort to present the historical development of the early Korean rockets in a paper which will be useful to both historians and scientists. The book entitled Kuk Cho Ore Sorye (1474) in the Korean language provided extensive rocket system description, however it required considerable research to interpret them. This paper is the first study of early Korean rockets and launchers. The major effort in this study is directed toward the development of design concepts and details of early Korean rockets. Also, to substantiate support of the historical data presented, some versions of the early Korean rockets were made according to their specifications and fired successfully by the author in 1981.

  10. Regression Rate Study in HTPB/GOX Hybrid Rocket Motors.

    OpenAIRE

    Philmon George; Krishnan, S; Lalitha Ramachandran; P. M. Varkey; Raveendran, M.

    1996-01-01

    The theoretical and experimenIal studies on hybrid rocket motor combustion research are briefly reviewed and the need for a clear understanding of hybrid rocket fuel regression rate mechanism is brought out. A test facility established at the Indian Institute of Technology, Madras, for hybrid rocket motor research study is described.The results of an experimental study on hydroxyl terminated polybutadiene and gaseous oxygen hybrid rocket motor are presented. Fuel grains with ammonium perchlor...

  11. Diet and habitat of the saiga antelope during the late Quaternary using stable carbon and nitrogen isotope ratios

    Science.gov (United States)

    Jürgensen, Jonathan; Drucker, Dorothée G.; Stuart, Anthony J.; Schneider, Matthias; Buuveibaatar, Bayarbaatar; Bocherens, Hervé

    2017-03-01

    Saiga antelope (Saiga tatarica) is one of the typical late Pleistocene species of the cold and arid mammoth steppe that covered a large area of northern hemisphere. The species is currently endangered and persists only in small areas of Central Asian steppe and desert ecosystems. The investigation of the ecology of the Pleistocene saiga using stable isotope ratios (δ13C, δ15N) aimed to decipher how different their diet and habitat were from those observed nowadays in relict populations. Up to 76 samples of bone collagen of ancient saiga from Western Europe, Siberia and Eastern Beringia were analysed and compared with 52 samples of hair and bone collagen of modern specimens from Kazahkstan, Russia and Mongolia. The δ13C values of the ancient saiga do not exhibit a clear trend over time. They cover the same range of values as the modern ones, from a C3-dominated to a C3-C4-dominated mixed diet (including probably Chenopodiaceae). In contrast, the δ15N values of fossil saigas are more variable and lower on average than the extant ones. The lowest δ15N values of ancient saiga are found around the Last Glacial Maximum, reflecting the influence of the cold conditions at that time. On the other hand, fossil saiga occupying the same regions as the historical and modern populations exhibit high δ15N values similar to the modern ones, confirming ecological continuity over time. Modern saiga is thus occupying just one of its potential diverse habitats they used in the past. Therefore, the extant saiga is not a refugee species confined to a suboptimal habitat. During the late Pleistocene, the saiga occupied a separate niche compared with the other ungulates of the mammoth steppe. However, this species could also adapt to a lichen-dominated diet normally seen in reindeer, leading to an isotopic overlap between the two species in south-western France and Alaska around the Last Glacial Maximum. This adaptation allowed a geographical expansion that does not correspond to a

  12. Influence of Rocket Engine Characteristics on Shaft Sealing Technology Needs

    Science.gov (United States)

    Keba, John E.

    1999-01-01

    This paper presents viewgraphs of The Influence of Rocket Engine Characteristics on Shaft Sealing Technology Needs. The topics include: 1) Rocket Turbomachinery Shaft Seals (Inter-Propellant-Seal (IPS) Systems, Lift-off Seal Systems, and Technology Development Needs); 2) Rocket Engine Characteristics (Engine cycles, propellants, missions, etc., Influence on shaft sealing requirements); and 3) Conclusions.

  13. 14 CFR 437.67 - Tracking a reusable suborbital rocket.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Tracking a reusable suborbital rocket. 437... a reusable suborbital rocket. A permittee must— (a) During permitted flight, measure in real time the position and velocity of its reusable suborbital rocket; and (b) Provide position and...

  14. Specific Impulses Losses in Solid Propellant Rockets

    Science.gov (United States)

    1974-12-17

    to use the collision function form proposed by Golovin to simplify this production term: 4C><=) <P- .: Accordingly: m hence, by integration: Now, we...November 21, 1940 in Paris, Seine. VFirst Thesis. "Contribution to the Study of Specific i Impulse Loss in Solid Propellant Rockets." Second Thesis

  15. An Analysis of Rocket Propulsion Testing Costs

    Science.gov (United States)

    Ramirez, Carmen; Rahman, Shamim

    2010-01-01

    The primary mission at NASA Stennis Space Center (SSC) is rocket propulsion testing. Such testing is commonly characterized as one of two types: production testing for certification and acceptance of engine hardware, and developmental testing for prototype evaluation or research and development (R&D) purposes. For programmatic reasons there is a continuing need to assess and evaluate the test costs for the various types of test campaigns that involve liquid rocket propellant test articles. Presently, in fact, there is a critical need to provide guidance on what represents a best value for testing and provide some key economic insights for decision-makers within NASA and the test customers outside the Agency. Hence, selected rocket propulsion test databases and references have been evaluated and analyzed with the intent to discover correlations of technical information and test costs that could help produce more reliable and accurate cost projections in the future. The process of searching, collecting, and validating propulsion test cost information presented some unique obstacles which then led to a set of recommendations for improvement in order to facilitate future cost information gathering and analysis. In summary, this historical account and evaluation of rocket propulsion test cost information will enhance understanding of the various kinds of project cost information; identify certain trends of interest to the aerospace testing community.

  16. The rocket problem in general relativity

    CERN Document Server

    Henriques, Pedro G

    2011-01-01

    We derive the covariant optimality conditions for rocket trajectories in general relativity, with and without a bound on the magnitude of the proper acceleration. The resulting theory is then applied to solve two specific problems: the minimum fuel consumption transfer between two galaxies in a FLRW model, and between two stable circular orbits in the Schwarzschild spacetime.

  17. Rocket and Laboratory Studies in Astronomy

    Science.gov (United States)

    Feldman, Paul D.

    2001-01-01

    This is the final report for NASA Grant NAG5-5122 and covers the period from March 1, 1997 to February 28, 2001. This grant was a continuation of a program in rocket and laboratory studies in ultraviolet astronomy that was supported by NASA grant NAG5-619. As of March 1, 2001, this program is continuing under grant NAG5-5315. During the period of the grant, annual status reports have been submitted detailing the scientific achievements and current objectives of each report period. These will not be repeated here. Among the highlights of the program are four successful rocket launches including participation in the campaign to study comet Hale-Bopp in April 1997. We have continued our emphasis on long-slit spectroscopy of extended sources in the shorter wavelength far-ultraviolet, necessitating the development of evacuated telescope/spectrograph payloads. Finally, we also note the use of our ultraviolet calibration facilities in support of other sounding rocket investigators and for other space missions such as the Far Ultraviolet Spectroscopic Explorer. We include a list of the sounding rocket launches performed under NASA sponsorship during this period, a list of Ph.D. degrees awarded to students who worked in this program, and a summary bibliography of publications between 1997 and 2001.

  18. NASA Sounding Rocket Program educational outreach

    Science.gov (United States)

    Eberspeaker, P. J.

    2005-08-01

    Educational and public outreach is a major focus area for the National Aeronautics and Space Administration (NASA). The NASA Sounding Rocket Program (NSRP) shares in the belief that NASA plays a unique and vital role in inspiring future generations to pursue careers in science, mathematics, and technology. To fulfill this vision, the NASA Sounding Rocket Program engages in a host of student flight projects providing unique and exciting hands-on student space flight experiences. These projects include single stage Orion missions carrying "active" high school experiments and "passive" Explorer School modules, university level Orion and Terrier-Orion flights, and small hybrid rocket flights as part of the Small-scale Educational Rocketry Initiative (SERI) currently under development. Efforts also include educational programs conducted as part of major campaigns. The student flight projects are designed to reach students ranging from Kindergarteners to university undergraduates. The programs are also designed to accommodate student teams with varying levels of technical capabilities - from teams that can fabricate their own payloads to groups that are barely capable of drilling and tapping their own holes. The program also conducts a hands-on student flight project for blind students in collaboration with the National Federation of the Blind. The NASA Sounding Rocket Program is proud of its role in inspiring the "next generation of explorers" and is working to expand its reach to all regions of the United States and the international community as well.

  19. Straw Rockets Are out of This World

    Science.gov (United States)

    Gillman, Joan

    2013-01-01

    To capture students' excitement and engage their interest in rocketships and visiting planets in the solar system, the author designed lessons that give students the opportunity to experience the joys and challenges of developing straw rockets, and then observing which design can travel the longest distance. The lessons are appropriate for…

  20. Government Relations: It's Not Rocket Science

    Science.gov (United States)

    Radway, Mike

    2007-01-01

    Many people in the early childhood education field are afraid of government relations work, intimidated by politicians, and believe the whole process is unseemly. The author asserts that they should not be afraid nor be intimidated because government relations is not rocket science and fundamentally officeholders are no different from the rest of…

  1. Simulation of Airplane and Rocket Trajectories

    Science.gov (United States)

    Wahbah, Magdy M.; Berning, Michael J.; Choy, Tony S.

    1987-01-01

    Simulation and Optimization of Rocket Trajectories program (SORT) contains comprehensive mathematical models for simulating aircraft dynamics, freely falling objects, and many types of ballistic trajectories. Provides high-fidelity, three-degrees-of-freedom simulation for atmospheric and exoatmospheric flight. It numerically models vehicle subsystems and vehicle environment. Used for wide range of simulations. Written in machine-independent FORTRAN 77.

  2. Scaled Rocket Testing in Hypersonic Flow

    Science.gov (United States)

    Dufrene, Aaron; MacLean, Matthew; Carr, Zakary; Parker, Ron; Holden, Michael; Mehta, Manish

    2015-01-01

    NASA's Space Launch System (SLS) uses four clustered liquid rocket engines along with two solid rocket boosters. The interaction between all six rocket exhaust plumes will produce a complex and severe thermal environment in the base of the vehicle. This work focuses on a recent 2% scale, hot-fire SLS base heating test. These base heating tests are short-duration tests executed with chamber pressures near the full-scale values with gaseous hydrogen/oxygen engines and RSRMV analogous solid propellant motors. The LENS II shock tunnel/Ludwieg tube tunnel was used at or near flight duplicated conditions up to Mach 5. Model development was strongly based on the Space Shuttle base heating tests with several improvements including doubling of the maximum chamber pressures and duplication of freestream conditions. Detailed base heating results are outside of the scope of the current work, rather test methodology and techniques are presented along with broader applicability toward scaled rocket testing in supersonic and hypersonic flow.

  3. Infrared spectroradiometer for rocket exhaust analysis

    Science.gov (United States)

    Herget, W. F.

    1968-01-01

    Infrared spectroradiometer measures high-resolution spectral absorption, emission, temperature, and concentration of chemical species in radically symmetric zones of the exhaust plumes of large rocket engines undergoing static firing tests. Measurements are made along predetermined lines of sight through the plume.

  4. Rocketing into the future the history and technology of rocket planes

    CERN Document Server

    van Pelt, Michel

    2012-01-01

    Rocketing into the Future journeys into the exciting world of rocket planes, examining the exotic concepts and actual flying vehicles that have been devised over the last one hundred years. Lavishly illustrated with over 150 photographs, it recounts the history of rocket planes from the early pioneers who attached simple rockets on to their wooden glider airplanes to the modern world of high-tech research vehicles. The book then looks at the possibilities for the future. The technological and economic challenges of the Space Shuttle proved insurmountable, and thus the program was unable to fulfill its promise of low-cost access to space. However, the burgeoning market of suborbital space tourism may yet give the necessary boost to the development of a truly reusable spaceplane.

  5. US Rocket Propulsion Industrial Base Health Metrics

    Science.gov (United States)

    Doreswamy, Rajiv

    2013-01-01

    The number of active liquid rocket engine and solid rocket motor development programs has severely declined since the "space race" of the 1950s and 1960s center dot This downward trend has been exacerbated by the retirement of the Space Shuttle, transition from the Constellation Program to the Space launch System (SLS) and similar activity in DoD programs center dot In addition with consolidation in the industry, the rocket propulsion industrial base is under stress. To Improve the "health" of the RPIB, we need to understand - The current condition of the RPIB - How this compares to past history - The trend of RPIB health center dot This drives the need for a concise set of "metrics" - Analogous to the basic data a physician uses to determine the state of health of his patients - Easy to measure and collect - The trend is often more useful than the actual data point - Can be used to focus on problem areas and develop preventative measures The nation's capability to conceive, design, develop, manufacture, test, and support missions using liquid rocket engines and solid rocket motors that are critical to its national security, economic health and growth, and future scientific needs. center dot The RPIB encompasses US government, academic, and commercial (including industry primes and their supplier base) research, development, test, evaluation, and manufacturing capabilities and facilities. center dot The RPIB includes the skilled workforce, related intellectual property, engineering and support services, and supply chain operations and management. This definition touches the five main segments of the U.S. RPIB as categorized by the USG: defense, intelligence community, civil government, academia, and commercial sector. The nation's capability to conceive, design, develop, manufacture, test, and support missions using liquid rocket engines and solid rocket motors that are critical to its national security, economic health and growth, and future scientific needs

  6. Flutter Analysis of RX-420 Balistic Rocket Fin Involving Rigid Body Modes of Rocket Structures

    OpenAIRE

    Novi Andria

    2013-01-01

    Flutter is a phenomenon that has brought a catastrophic failure to the flight vehicle structure. In this experiment, flutter was analyzed for its symmetric and antisymmetric configuration to understand the effect of rocket rigid modes to the fin flutter characteristic. This research was also expected to find out the safety level of RX-420 structure design. The analysis was performed using half rocket model. Fin structure used in this research was a fin which has semispan 600 mm, thickness 12 ...

  7. Peregrine 100-km Sounding Rocket Project

    Science.gov (United States)

    Zilliac, Gregory

    2012-01-01

    The Peregrine Sounding Rocket Program is a joint basic research program of NASA Ames Research Center, NASA Wallops, Stanford University, and the Space Propulsion Group, Inc. (SPG). The goal is to determine the applicability of this technology to a small launch system. The approach is to design, build, and fly a stable, efficient liquefying fuel hybrid rocket vehicle to an altitude of 100 km. The program was kicked off in October of 2006 and has seen considerable progress in the subsequent 18 months. This research group began studying liquifying hybrid rocket fuel technology more than a decade ago. The overall goal of the research was to gain a better understanding of the fundamental physics of the liquid layer entrainment process responsible for the large increase in regression rate observed in these fuels, and to demonstrate the effect of increased regression rate on hybrid rocket motor performance. At the time of this reporting, more than 400 motor tests were conducted with a variety of oxidizers (N2O, GOx, LOx) at ever increasing scales with thrust levels from 5 to over 15,000 pounds (22 N to over 66 kN) in order to move this technology from the laboratory to practical applications. The Peregrine program is the natural next step in this development. A number of small sounding rockets with diameters of 3, 4, and 6 in. (7.6, 10.2, and 15.2 cm) have been flown, but Peregrine at a diameter of 15 in. (38.1 cm) and 14,000-lb (62.3-kN) thrust is by far the largest system ever attempted and will be one of the largest hybrids ever flown. Successful Peregrine flights will set the stage for a wide range of applications of this technology.

  8. Development of Kabila rocket: A radioisotope heated thermionic plasma rocket engine

    Directory of Open Access Journals (Sweden)

    Kalomba Mboyi

    2015-04-01

    Full Text Available A new type of plasma rocket engine, the Kabila rocket, using a radioisotope heated thermionic heating chamber instead of a conventional combustion chamber or catalyst bed is introduced and it achieves specific impulses similar to the ones of conventional solid and bipropellant rockets. Curium-244 is chosen as a radioisotope heat source and a thermal reductive layer is also used to obtain precise thermionic emissions. The self-sufficiency principle is applied by simultaneously heating up the emitting material with the radioisotope decay heat and by powering the different valves of the plasma rocket engine with the same radioisotope decay heat using a radioisotope thermoelectric generator. This rocket engine is then benchmarked against a 1 N hydrazine thruster configuration operated on one of the Pleiades-HR-1 constellation spacecraft. A maximal specific impulse and power saving of respectively 529 s and 32% are achieved with helium as propellant. Its advantages are its power saving capability, high specific impulses and simultaneous ease of storage and restart. It can however be extremely voluminous and potentially hazardous. The Kabila rocket is found to bring great benefits to the existing spacecraft and further research should optimize its geometric characteristics and investigate the physical principals of its operation.

  9. Measurements of temperature profiles at the exit of small rockets.

    Science.gov (United States)

    Griggs, M; Harshbarger, F C

    1966-02-01

    The sodium line reversal technique was used to determine the reversal temperature profile across the exit of small rockets. Measurements were made on one 73-kg thrust rocket, and two 23-kg thrust rockets with different injectors. The large rocket showed little variation of reversal temperature across the plume. However, the 23-kg rockets both showed a large decrease of reversal temperature from the axis to the edge of the plume. In addition, the sodium line reversal technique of temperature measurement was compared with an infrared technique developed in these laboratories.

  10. Replacement of chemical rocket launchers by beamed energy propulsion.

    Science.gov (United States)

    Fukunari, Masafumi; Arnault, Anthony; Yamaguchi, Toshikazu; Komurasaki, Kimiya

    2014-11-01

    Microwave Rocket is a beamed energy propulsion system that is expected to reach space at drastically lower cost. This cost reduction is estimated by replacing the first-stage engine and solid rocket boosters of the Japanese H-IIB rocket with Microwave Rocket, using a recently developed thrust model in which thrust is generated through repetitively pulsed microwave detonation with a reed-valve air-breathing system. Results show that Microwave Rocket trajectory, in terms of velocity versus altitude, can be designed similarly to the current H-IIB first stage trajectory. Moreover, the payload ratio can be increased by 450%, resulting in launch-cost reduction of 74%.

  11. Mixing and reaction processes in rocket based combined cycle and conventional rocket engines

    Science.gov (United States)

    Lehman, Matthew Kurt

    Raman spectroscopy was used to make species measurements in two rocket engines. An airbreathing rocket, the rocket based combined cycle (RBCC) engine, and a conventional rocket were investigated. A supersonic rocket plume mixing with subsonic coflowing air characterizes the ejector mode of the RBCC engine. The mixing length required for the air and plume to become homogenous is a critical dimension. For the conventional rocket experiments, a gaseous oxygen/gaseous hydrogen single-element shear coaxial injector was used. Three chamber Mach number conditions, 0.1, 0.2 and 0.3, were chosen to assess the effect of Mach number on mixing. The flow within the chamber was entirely subsonic. For the RBCC experiments, vertical Raman line measurements were made at multiple axial locations downstream from the rocket nozzle plane. Species profiles assessed the mixing progress between the supersonic plume and subsonic air. For the conventional rocket, Raman line measurements were made downstream from the injector face. The goal was to evaluate the effect of increased chamber Mach number on injector mixing/reaction. For both engines, quantitative and qualitative information was collected for computational fluid dynamics (CFD development. The RBCC experiments were conducted for three distinct geometries. The primary flow path was a diffuse and afterburner design with a direct-connect air supply. A sea-level static (SLS) version and a thermally choked variant were also tested. The experimental results show that mixing length increases with additional coflow air in the DAB geometry. Operation of variable rocket mixture ratios at identical air flow rates did not significantly affect the mixing length. The thermally choked variant had a longer mixing length compared to the DAB geometry, and the SLS modification had a shorter mixing length due to a reduced air flow. The conventional rocket studies focused on the effect of chamber Mach number on primary injector mixing. Chamber Mach

  12. Pressure-Equalizing Cradle for Booster Rocket Mounting

    Science.gov (United States)

    Rutan, Elbert L. (Inventor)

    2015-01-01

    A launch system and method improve the launch efficiency of a booster rocket and payload. A launch aircraft atop which the booster rocket is mounted in a cradle, is flown or towed to an elevation at which the booster rocket is released. The cradle provides for reduced structural requirements for the booster rocket by including a compressible layer, that may be provided by a plurality of gas or liquid-filled flexible chambers. The compressible layer contacts the booster rocket along most of the length of the booster rocket to distribute applied pressure, nearly eliminating bending loads. Distributing the pressure eliminates point loading conditions and bending moments that would otherwise be generated in the booster rocket structure during carrying. The chambers may be balloons distributed in rows and columns within the cradle or cylindrical chambers extending along a length of the cradle. The cradle may include a manifold communicating gas between chambers.

  13. 藏羚羊种群资源及其保护%Resources Regarding Populations of Tibetan Antelope (Pantholops hodgsoni)and the Status of Its Protection

    Institute of Scientific and Technical Information of China (English)

    吴晓民; 张洪峰

    2011-01-01

    藏羚羊(Pantholops hodgsoni)属中国国家I级保护动物,被列入(CITES)公约附录I.藏羚羊主要分布于中国青海、西藏、新疆和四川四省(区)海拔3 700~5 500 m的高山荒漠草甸草原和高原草原等环境中.独特的高原生态环境,使藏羚羊在漫长的进化过程中,从外部形态、内部器官结构、生态习性和行为上都适应了青藏高原独特且恶劣的自然条件,从而具有最优秀的基因,因此,藏羚羊被公认为青藏高原动物区系的典型代表和自然生态系统的重要指示物种,在科学研究、生态平衡乃至人文和美学等方面都具有难以估量的价值.20世纪80年代末到90年代,出产于克什米尔的稀有奢华的藏羚羊绒披肩(沙图什)就深受贵族和富人们的青睐,被视为财富和地位的象征,巨额利润促使盗猎者大最捕杀藏羚羊,后经国家林业、环保等部门加大保护力度,加强保护区及栖息地建设等诸多措施后,种群数量及分布区逐渐恢复,但目前藏羚羊面临着生存环境、人类经济社会发展、盗猎的巨大压力,物种整体抗逆境能力仍然十分脆弱.%Tibetan antelope is listed as the first grade wildlife of China, and included in the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendix Ⅰ.It is mainly located in alpine desert meadow steppe and upland grassland from 3 700 to 5 500 metres, Tibet, Xinjiang, Qinghai and Sichuan Provinces of China. During the long process of evolution,Tibetan antelope was adapt to unique and formidable natural conditions from the aspects of the external form, internal organ structure, ecological habits and behavior. It was recognized for the department of typical representative Qinghai-Tibet plateau animal area and important indicating species in natural ecological system,which had inestimable value in scientific research, ecological balance and humanities and aesthetics. Due to luxury of shawl

  14. Processes Affecting the Trihalomethane Concentrations Associated with the Third Injection, Storage, and Recovery Test at Lancaster, Antelope Valley, California, March 1998 through April 1999

    Science.gov (United States)

    Fram, Miranda S.; Bergamaschi, Brian A.; Goodwin, Kelly D.; Fujii, Roger; Clark, Jordan F.

    2003-01-01

    The formation and fate of trihalomethanes (THM) during the third injection, storage, and recovery test at Lancaster, Antelope Valley, California, were investigated as part of a program to assess the long-term feasibility of using injection, storage, and recovery as a water-supply method and as a way to reduce water-level declines and land-subsidence in the Antelope Valley. The program was conducted by the U.S. Geological Survey in cooperation with the Los Angeles County Department of Public Works and the Antelope Valley-East Kern Water Agency. The water used for injection, storage, and recovery must be disinfected before injection and thus contains THMs and other disinfection by-products. THMs (chloroform, CHCl3, bromodichloromethane, CHCl2Br, dibromochloromethane, CHClBr2, and bromoform, CHBr3) are formed by reaction between natural dissolved organic carbon that is present in water and chlorine that is added during the disinfection step of the drinking water treatment process. THMs are carcinogenic compounds, and their concentrations in drinking water are regulated by the U.S. Environmental Protection Agency. During previous cycles of the Lancaster program, extracted water still contained measurable concentrations of THMs long after continuous pumping had extracted a greater volume of water than had been injected. This raised concerns about the potential long-term effect of injection, storage, and recovery cycles on ground-water quality in Antelope Valley aquifers. The primary objectives of this investigation were to determine (1) what controlled continued THM formation in the aquifer after injection, (2) what caused of the persistence of THMs in the extracted water, even after long periods of pumping, (3) what controlled the decrease of THM concentrations during the extraction period, and (4) the potential for natural attenuation of THMs in the aquifer. Laboratory experiments on biodegradation of THMs in microcosms of aquifer materials indicate that aquifer

  15. A long-standing Pleistocene refugium in southern Africa and a mosaic of refugia in East Africa: insights from mtDNA and the common eland antelope

    DEFF Research Database (Denmark)

    Lorenzen, Eline; Masembe, Charles; Arctander, Peter;

    2010-01-01

    East Africa could result from colonization following extinction from the region. Only two other dated African ungulate phylogenies have been published, applying different methods, and the similarity of dates obtained from the three distinct approaches indicates a significant event c. 200 ka, which left....... Phylogeographic analysis of the common eland antelope, Taurotragus oryx (Bovidae), was used to assess these hypotheses and the existence of genetic signatures of Pleistocene climate change. Location The sub-Saharan savanna biome of East and southern Africa. Methods Mitochondrial DNA control-region fragments (414......-based methods and a calibrated fossil root of 1.6 Ma for the split between the common eland and the giant eland, Taurotragus derbianus. Results Two major phylogeographic lineages comprising East and southern African localities, respectively, were separated by a net nucleotide distance of 4.7%. A third...

  16. NASA's Hydrogen Outpost: The Rocket Systems Area at Plum Brook Station

    Science.gov (United States)

    Arrighi, Robert S.

    2016-01-01

    "There was pretty much a general knowledge about hydrogen and its capabilities," recalled former researcher Robert Graham. "The question was, could you use it in a rocket engine? Do we have the technology to handle it? How will it cool? Will it produce so much heat release that we can't cool the engine? These were the questions that we had to address." The National Aeronautics and Space Administration's (NASA) Glenn Research Center, referred to historically as the Lewis Research Center, made a concerted effort to answer these and related questions in the 1950s and 1960s. The center played a critical role transforming hydrogen's theoretical potential into a flight-ready propellant. Since then NASA has utilized liquid hydrogen to send humans and robots to the Moon, propel dozens of spacecraft across the universe, orbit scores of satellite systems, and power 135 space shuttle flights. Rocket pioneers had recognized hydrogen's potential early on, but its extremely low boiling temperature and low density made it impracticable as a fuel. The Lewis laboratory first demonstrated that liquid hydrogen could be safely utilized in rocket and aircraft propulsion systems, then perfected techniques to store, pump, and cleanly burn the fuel, as well as use it to cool the engine. The Rocket Systems Area at Lewis's remote testing area, Plum Brook Station, played a little known, but important role in the center's hydrogen research efforts. This publication focuses on the activities at the Rocket Systems Area, but it also discusses hydrogen's role in NASA's space program and Lewis's overall hydrogen work. The Rocket Systems Area included nine physically modest test sites and three test stands dedicated to liquid-hydrogen-related research. In 1962 Cleveland Plain Dealer reporter Karl Abram claimed, "The rocket facility looks more like a petroleum refinery. Its test rigs sprout pipes, valves and tanks. During the night test runs, excess hydrogen is burned from special stacks in the best

  17. Development of small solid rocket boosters for the ILR-33 sounding rocket

    Science.gov (United States)

    Nowakowski, Pawel; Okninski, Adam; Pakosz, Michal; Cieslinski, Dawid; Bartkowiak, Bartosz; Wolanski, Piotr

    2017-09-01

    This paper gives an overview of the development of a 6000 Newton-class solid rocket motor for suborbital applications. The design configuration and results of interior ballistics calculations are given. The initial use of the motor as the main propulsion system of the H1 experimental in-flight test platform, within the Polish Small Sounding Rocket Program, is presented. Comparisons of theoretical and experimental performance are shown. Both on-ground and in-flight tests are discussed. A novel composite-case manufacturing technology, which enabled to reach high propellant mass fractions, was validated and significant cost-reductions were achieved. This paper focuses on the process of adapting the design for use as the booster stage of the ILR-33 sounding rocket, under development at the Institute of Aviation in Warsaw, Poland. Parallel use of two of the flight-proven rocket motors along with the main stage is planned. The process of adapting the rocket motor for booster application consists of stage integration, aerothermodynamics and reliability analyses. The separation mechanism and environmental impact are also discussed within this paper. Detailed performance analysis with focus on propellant grain geometry is provided. The evolution of the design since the first flights of the H1 rocket is covered and modifications of the manufacturing process are described. Issues of simultaneous ignition of two motors and their non-identical performance are discussed. Further applications and potential for future development are outlined. The presented results are based on the initial work done by the Rocketry Group of the Warsaw University of Technology Students' Space Association. The continuation of the Polish Small Sounding Rocket Program on a larger scale at the Institute of Aviation proves the value of the outcomes of the initial educational project.

  18. Rocket center Peenemünde — Personal memories

    Science.gov (United States)

    Dannenberg, Konrad; Stuhlinger, Ernst

    Von Braun built his first rockets as a young teenager. At 14, he started making plans for rockets for human travel to the Moon and Mars. The German Army began a rocket program in 1929. Two years later, Colonel (later General) Becker contacted von Braun who experimented with rockets in Berlin, gave him a contract in 1932, and, jointly with the Air Force, in 1936 built the rocket center Peenemünde where von Braun and his team developed the A-4 (V-2) rocket under Army auspices, while the Air Force developed the V-1 (buzz bomb), wire-guided bombs, and rocket planes. Albert Speer, impressed by the work of the rocketeers, allowed a modest growth of the Peenemünde project; this brought Dannenberg to the von Braun team in 1940. Hitler did not believe in rockets; he ignored the A-4 project until 1942 when he began to support it, expecting that it could turn the fortunes of war for him. He drastically increased the Peenemünde work force and allowed the transfer of soldiers from the front to Peenemünde; that was when Stuhlinger, in 1943, came to Peenemünde as a Pfc.-Ph.D. Later that year, Himmler wrenched the authority over A-4 production out of the Army's hands, put it under his command, and forced production of the immature rocket at Mittelwerk, and its military deployment against targets in France, Belgium, and England. Throughout the development of the A-4 rocket, von Braun was the undisputed leader of the project. Although still immature by the end of the war, the A-4 had proceeded to a status which made it the first successful long-range precision rocket, the prototype for a large number of military rockets built by numerous nations after the war, and for space rockets that launched satellites and traveled to the Moon and the planets.

  19. Nuclear rocket using indigenous Martian fuel NIMF

    Science.gov (United States)

    Zubrin, Robert

    1991-01-01

    In the 1960's, Nuclear Thermal Rocket (NTR) engines were developed and ground tested capable of yielding isp of up to 900 s at thrusts up to 250 klb. Numerous trade studies have shown that such traditional hydrogen fueled NTR engines can reduce the inertial mass low earth orbit (IMLEO) of lunar missions by 35 percent and Mars missions by 50 to 65 percent. The same personnel and facilities used to revive the hydrogen NTR can also be used to develop NTR engines capable of using indigenous Martian volatiles as propellant. By putting this capacity of the NTR to work in a Mars descent/acent vehicle, the Nuclear rocket using Indigenous Martian Fuel (NIMF) can greatly reduce the IMLEO of a manned Mars mission, while giving the mission unlimited planetwide mobility.

  20. Ignition transient analysis of solid rocket motor

    Science.gov (United States)

    Han, Samuel S.

    1991-01-01

    Measurement data on the performance of Space Shuttle Solid Rocket Motor show wide variations in the head-end pressure changes and the total thrust build-up during the ignition transient periods. To analyze the flow and thermal behavior in the tested solid rocket motors, a 1-dimensional, ideal gas flow model via the SIMPLE algorithm was developed. Numerical results showed that burning patterns in the star-shaped head-end segment of the propellant and the erosive burning rate are two important factors controlling the ignition transients. The objective of this study is to extend the model to include the effects of aluminum particle commonly used in solid propellants. To treat the effects of aluminum-oxide particles in the combustion gas, conservation of mass, momentum, and energy equations for the particles are added in the numerical formulation and integrated by an inter-phase-slip algorithm.

  1. Performance Charts for Multistage Rocket Boosters

    Science.gov (United States)

    MacKay, John S.; Weber, Richard J.

    1961-01-01

    Charts relating the stage propellant fractions are given for two-and three-stage rockets launching payloads into nominal low-altitude circular orbits about the earth. A simple method is described for extending these data to higher orbit or escape missions. Various combinations of stages using RP - liquid-oxygen and hydrogen - liquid-oxygen propellants are considered. However, the results can be generalized with little error to any other propellant combination.Charts relating the stage propellant fractions are given for two-and three-stage rockets launching payloads into nominal low-altitude circular orbits about the earth. A simple method is described for extending these data to higher orbit or escape missions. Various combinations of stages using RP - liquid-oxygen and hydrogen - liquid-oxygen propellants are considered. However, the results can be generalized with little error to any other propellant combination.

  2. Rocket plume tomography of combustion species

    OpenAIRE

    2001-01-01

    Interest in accurate detection and targeting of aggressor missiles has received considerable interest with the national priority of developing a missile defense system. Understanding the thermal signatures of the exhaust plumes of such missiles is key to accomplishing that mission. Before signature models can be precisely developed for specific rockets, the radiation of the molecular or combustion species within those plumes must be accurately predicted. A combination translation / rotation s...

  3. Design Study: Rocket Based MHD Generator

    Science.gov (United States)

    1997-01-01

    This report addresses the technical feasibility and design of a rocket based MHD generator using a sub-scale LOx/RP rocket motor. The design study was constrained by assuming the generator must function within the performance and structural limits of an existing magnet and by assuming realistic limits on (1) the axial electric field, (2) the Hall parameter, (3) current density, and (4) heat flux (given the criteria of heat sink operation). The major results of the work are summarized as follows: (1) A Faraday type of generator with rectangular cross section is designed to operate with a combustor pressure of 300 psi. Based on a magnetic field strength of 1.5 Tesla, the electrical power output from this generator is estimated to be 54.2 KW with potassium seed (weight fraction 3.74%) and 92 KW with cesium seed (weight fraction 9.66%). The former corresponds to a enthalpy extraction ratio of 2.36% while that for the latter is 4.16%; (2) A conceptual design of the Faraday MHD channel is proposed, based on a maximum operating time of 10 to 15 seconds. This concept utilizes a phenolic back wall for inserting the electrodes and inter-electrode insulators. Copper electrode and aluminum oxide insulator are suggested for this channel; and (3) A testing configuration for the sub-scale rocket based MHD system is proposed. An estimate of performance of an ideal rocket based MHD accelerator is performed. With a current density constraint of 5 Amps/cm(exp 2) and a conductivity of 30 Siemens/m, the push power density can be 250, 431, and 750 MW/m(sup 3) when the induced voltage uB have values of 5, 10, and 15 KV/m, respectively.

  4. Nuclear Thermal Rocket Element Environmental Simulator (NTREES)

    Science.gov (United States)

    Emrich, William J.

    2008-01-01

    To support a potential future development of a nuclear thermal rocket engine, a state-of-the-art non nuclear experimental test setup has been constructed to evaluate the performance characteristics of candidate fuel element materials and geometries in representative environments. The test device simulates the environmental conditions (minus the radiation) to which nuclear rocket fuel components could be subjected during reactor operation. Test articles mounted in the simulator are inductively heated in such a manner as to accurately reproduce the temperatures and heat fluxes normally expected to occur as a result of nuclear fission while at the same time being exposed to flowing hydrogen. This project is referred to as the Nuclear Thermal Rocket Element Environment Simulator or NTREES. The NTREES device is located at the Marshall Space flight Center in a laboratory which has been modified to accommodate the high powers required to heat the test articles to the required temperatures and to handle the gaseous hydrogen flow required for the tests. Other modifications to the laboratory include the installation of a nitrogen gas supply system and a cooling water supply system. During the design and construction of the facility, every effort was made to comply with all pertinent regulations to provide assurance that the facility could be operated in a safe and efficient manner. The NTREES system can currently supply up to 50 kW of inductive heating to the fuel test articles, although the facility has been sized to eventually allow test article heating levels of up to several megawatts.

  5. Computational simulation of liquid rocket injector anomalies

    Science.gov (United States)

    Przekwas, A. J.; Singhal, A. K.; Tam, L. T.; Davidian, K.

    1986-01-01

    A computer model has been developed to analyze the three-dimensional two-phase reactive flows in liquid fueled rocket combustors. The model is designed to study the influence of liquid propellant injection nonuniformities on the flow pattern, combustion and heat transfer within the combustor. The Eulerian-Lagrangian approach for simulating polidisperse spray flow, evaporation and combustion has been used. Full coupling between the phases is accounted for. A nonorthogonal, body fitted coordinate system along with a conservative control volume formulation is employed. The physical models built into the model include a kappa-epsilon turbulence model, a two-step chemical reaction, and the six-flux radiation model. Semiempirical models are used to describe all interphase coupling terms as well as chemical reaction rates. The purpose of this study was to demonstrate an analytical capability to predict the effects of reactant injection nonuniformities (injection anomalies) on combustion and heat transfer within the rocket combustion chamber. The results show promising application of the model to comprehensive modeling of liquid propellant rocket engines.

  6. Nuclear Thermal Rocket Element Environmental Simulator (NTREES)

    Science.gov (United States)

    Emrich, William J., Jr.

    2008-01-01

    To support the eventual development of a nuclear thermal rocket engine, a state-of-the-art experimental test setup has been constructed to evaluate the performance characteristics of candidate fuel element materials and geometries in representative environments. The test device simulates the environmental conditions (minus the radiation) to which nuclear rocket fuel components will be subjected during reactor operation. Test articles mounted in the simulator are inductively heated in such a manner as to accurately reproduce the temperatures and heat fluxes normally expected to occur as a result of nuclear fission while at the same time being exposed to flowing hydrogen. This project is referred to as the Nuclear Thermal Rocket Element Environment Simulator or NTREES. The NTREES device is located at the Marshall Space flight Center in a laboratory which has been modified to accommodate the high powers required to heat the test articles to the required temperatures and to handle the gaseous hydrogen flow required for the tests. Other modifications to the laboratory include the installation of a nitrogen gas supply system and a cooling water supply system. During the design and construction of the facility, every effort was made to comply with all pertinent regulations to provide assurance that the facility could be operated in a safe and efficient manner. The NTREES system can currently supply up to 50 kW of inductive heating to the fuel test articles, although the facility has been sized to eventually allow test article heating levels of up to several megawatts.

  7. Groundwater-Quality Data in the Antelope Valley Study Unit, 2008: Results from the California GAMA Program

    Science.gov (United States)

    Schmitt, Stephen J.; Milby Dawson, Barbara J.; Belitz, Kenneth

    2009-01-01

    Groundwater quality in the approximately 1,600 square-mile Antelope Valley study unit (ANT) was investigated from January to April 2008 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of the quality of raw groundwater used for public water supplies within ANT, and to facilitate statistically consistent comparisons of groundwater quality throughout California. Samples were collected from 57 wells in Kern, Los Angeles, and San Bernardino Counties. Fifty-six of the wells were selected using a spatially distributed, randomized, grid-based method to provide statistical representation of the study area (grid wells), and one additional well was selected to aid in evaluation of specific water-quality issues (understanding well). The groundwater samples were analyzed for a large number of organic constituents (volatile organic compounds [VOCs], gasoline additives and degradates, pesticides and pesticide degradates, fumigants, and pharmaceutical compounds), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), and radioactive constituents (gross alpha and gross beta radioactivity, radium isotopes, and radon-222). Naturally occurring isotopes (strontium, tritium, and carbon-14, and stable isotopes of hydrogen and oxygen in water), and dissolved noble gases also were measured to help identify the sources and ages of the sampled groundwater. In total, 239 constituents and water-quality indicators (field parameters) were investigated. Quality

  8. The 2003 Goddard Rocket Replica Project: A Reconstruction of the World's First Functional Liquid Rocket System

    Science.gov (United States)

    Farr, R. A.; Elam, S. K.; Hicks, G. D.; Sanders, T. M.; London, J. R.; Mayne, A. W.; Christensen, D. L.

    2003-01-01

    As a part of NASA s 2003 Centennial of Flight celebration, engineers and technicians at Marshall Space Flight Center (MSFC), Huntsville, Alabama, in cooperation with the Alabama-Mississippi AIAA Section, have reconstructed historically accurate, functional replicas of Dr. Robert H. Goddard s 1926 first liquid- fuel rocket. The purposes of this project were to clearly understand, recreate, and document the mechanisms and workings of the 1926 rocket for exhibit and educational use, creating a vital resource for researchers studying the evolution of liquid rocketry for years to come. The MSFC team s reverse engineering activity has created detailed engineering-quality drawings and specifications describing the original rocket and how it was built, tested, and operated. Static hot-fire tests, as well as flight demonstrations, have further defined and quantified the actual performance and engineering actual performance and engineering challenges of this major segment in early aerospace history.

  9. 藏羚羊雌性种群的迁徙行为和产仔行为%Migratory and calving behavior of Tibetan antelope population

    Institute of Scientific and Technical Information of China (English)

    George B.SCHALLER; 康蔼黎; 蔡新斌; 刘炎林

    2006-01-01

    A migratory population of female Tibetan antelope or chiru was studied on its calving ground in the western Kun lun Mountains, Xinjiang in June - July 2005. It was estimated that 4 000 - 4 500 females were in the 1 200 km2 calving area but most births were concentrated in 350 km2. The habitat at 4 500 -5 000 m in elevation had vegetation coverage of less than 5%, principally the dwarf shrub Ceratoides compacta. Young were born 18 June -7 July with a peak 24 June -3 July. Only about 40% of adult females had young, a low fecundity possibly the result of heavy winter snows leading to poor physical condition. Wolf, red fox, and birds of prey killed a few chiru but predators were scarce; most mortality was unre lated to predation. Females arrived at the calving grounds in late May and early June from the west of Tibet, and by early July started their return migration. It remains unclear why chiru migrate to that site. Analysis of chiru food plants showed no marked difference in nutritive values at this season between the calving grounds and the southern range. Escape from predators, parasitic insects, and people with their livestock may all have a role. Based on the study, we suggest that the main calving ground requires strict protection from disturbance, and a large reserve in the region needs to be established.%2005年6~7月,我们在新疆昆仑山西部的一处藏羚羊繁殖地,对一个雌性藏羚羊的迁徙种群进行了研究.整个调查区域的海拔是4 500~5 000 m,植被覆盖率小于5%,主要植被是垫状驼绒藜(Ceratoides compacta).根据研究结果,我们估计在本产仔季节,共有4 000~4 500头雌性藏羚羊迁徙聚集到一个1 200 km2的区域内,集中产仔地面积约为350 km2.产仔的高峰期是在6月18日~7月7日,其间只有40%的成年雌性产仔,这可能和2004年冬西藏阿鲁盆地的降雪量较大导致藏羚羊在交配期和怀孕期身体条件较弱有关.这个区域的雌

  10. Regression Rate Study in HTPB/GOX Hybrid Rocket Motors.

    Directory of Open Access Journals (Sweden)

    Philmon George

    1996-12-01

    Full Text Available The theoretical and experimenIal studies on hybrid rocket motor combustion research are briefly reviewed and the need for a clear understanding of hybrid rocket fuel regression rate mechanism is brought out. A test facility established at the Indian Institute of Technology, Madras, for hybrid rocket motor research study is described.The results of an experimental study on hydroxyl terminated polybutadiene and gaseous oxygen hybrid rocket motor are presented. Fuel grains with ammonium perchlorate "additive" have shownenhanced oxidizermass flux dependence. Smallergrains have higher regression rates than those of the larger ones.

  11. Unsupervised Anomaly Detection for Liquid-Fueled Rocket Prop...

    Data.gov (United States)

    National Aeronautics and Space Administration — Title: Unsupervised Anomaly Detection for Liquid-Fueled Rocket Propulsion Health Monitoring. Abstract: This article describes the results of applying four...

  12. Potential Climate and Ozone Impacts From Hybrid Rocket Engine Emissions

    Science.gov (United States)

    Ross, M.

    2009-12-01

    Hybrid rocket engines that use N2O as an oxidizer and a solid hydrocarbon (such as rubber) as a fuel are relatively new. Little is known about the composition of such hybrid engine emissions. General principles and visual inspection of hybrid plumes suggest significant soot and possibly NO emissions. Understanding hybrid rocket emissions is important because of the possibility that a fleet of hybrid powered suborbital rockets will be flying on the order of 1000 flights per year by 2020. The annual stratospheric emission for these rockets would be about 10 kilotons, equal to present day solid rocket motor (SRM) emissions. We present a preliminary analysis of the magnitude of (1) the radiative forcing from soot emissions and (2) the ozone depletion from soot and NO emissions associated with such a fleet of suborbital hybrid rockets. Because the details of the composition of hybrid emissions are unknown, it is not clear if the ozone depletion caused by these hybrid rockets would be more or less than the ozone depletion from SRMs. We also consider the climate implications associated with the N2O production and use requirements for hybrid rockets. Finally, we identify the most important data collection and modeling needs that are required to reliably assess the complete range of environmental impacts of a fleet of hybrid rockets.

  13. Numerical Simulation of Rocket Exhaust Interaction with Lunar Soil Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Rocket plume impingement may cause significant damage and contaminate co-landed spacecraft and surrounding habitat structures during Lunar landing operations. Under...

  14. Numerical Simulation of Rocket Exhaust Interaction with Lunar Soil Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Rocket plume impingement can cause significant damage and contaminate co-landing spacecraft and surrounding habitat structures during lunar landing operations. CFDRC...

  15. Coning motion stability of wrap around fin rockets

    Institute of Scientific and Technical Information of China (English)

    MAO XueRui; YANG ShuXing; XU Yong

    2007-01-01

    Both the asymptotical stability criterion and the bounded stability criterion of the coning motion for wrap around fin (WAF) rockets are proposed through the analysis of coning motion equations, which can be easily used to determine the existence of the coning motion during the rocket design. The correctness of the criterions is verified by mathematical simulation examples of a WAF rocket with different setting angles. It is also found that the setting angle of WAF has great effects on the rolling moment and side moment of the rocket.

  16. Coning motion stability of wrap around fin rockets

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Both the asymptotical stability criterion and the bounded stability criterion of the coning motion for wrap around fin(WAF) rockets are proposed through the analy-sis of coning motion equations,which can be easily used to determine the exis-tence of the coning motion during the rocket design. The correctness of the crite-rions is verified by mathematical simulation examples of a WAF rocket with differ-ent setting angles. It is also found that the setting angle of WAF has great effects on the rolling moment and side moment of the rocket.

  17. Nuclear Thermal Rocket (NTR) Development Risk Communication

    Science.gov (United States)

    Kim, Tony

    2014-01-01

    There are clear advantages of development of a Nuclear Thermal Rocket (NTR) for a crewed mission to Mars. NTR for in-space propulsion enables more ambitious space missions by providing high thrust at high specific impulse (approximately 900 sec) that is 2 times the best theoretical performance possible for chemical rockets. Missions can be optimized for maximum payload capability to take more payload with reduced total mass to orbit; saving cost on reduction of the number of launch vehicles needed. Or missions can be optimized to minimize trip time significantly to reduce the deep space radiation exposure to the crew. NTR propulsion technology is a game changer for space exploration. However, "NUCLEAR" is a word that is feared and vilified by some groups and the hostility towards development of any nuclear systems can meet great opposition by the public as well as from national leaders and people in authority. Communication of nuclear safety will be critical to the success of the development of the NTR. Why is there a fear of nuclear? A bomb that can level a city is a scary weapon. The first and only times the Nuclear Bomb was used in a war was on Hiroshima and Nagasaki during World War 2. The "Little Boy" atomic bomb was dropped on Hiroshima on August 6, 1945 and the "Fat Man" on Nagasaki 3 days later on August 9th. Within the first 4 months of bombings, 90- 166 thousand people died in Hiroshima and 60-80 thousand died in Nagasaki. It is important to note for comparison that over 500 thousand people died and 5 million made homeless due to strategic bombing (approximately 150 thousand tons) of Japanese cities and war assets with conventional non-nuclear weapons between 1942- 1945. A major bombing campaign of "firebombing" of Tokyo called "Operation Meetinghouse" on March 9 and 10 consisting of 334 B-29's dropped approximately1,700 tons of bombs around 16 square mile area and over 100 thousand people have been estimated to have died. The declaration of death is very

  18. Parallelization of Rocket Engine System Software (Press)

    Science.gov (United States)

    Cezzar, Ruknet

    1996-01-01

    The main goal is to assess parallelization requirements for the Rocket Engine Numeric Simulator (RENS) project which, aside from gathering information on liquid-propelled rocket engines and setting forth requirements, involve a large FORTRAN based package at NASA Lewis Research Center and TDK software developed by SUBR/UWF. The ultimate aim is to develop, test, integrate, and suitably deploy a family of software packages on various aspects and facets of rocket engines using liquid-propellants. At present, all project efforts by the funding agency, NASA Lewis Research Center, and the HBCU participants are disseminated over the internet using world wide web home pages. Considering obviously expensive methods of actual field trails, the benefits of software simulators are potentially enormous. When realized, these benefits will be analogous to those provided by numerous CAD/CAM packages and flight-training simulators. According to the overall task assignments, Hampton University's role is to collect all available software, place them in a common format, assess and evaluate, define interfaces, and provide integration. Most importantly, the HU's mission is to see to it that the real-time performance is assured. This involves source code translations, porting, and distribution. The porting will be done in two phases: First, place all software on Cray XMP platform using FORTRAN. After testing and evaluation on the Cray X-MP, the code will be translated to C + + and ported to the parallel nCUBE platform. At present, we are evaluating another option of distributed processing over local area networks using Sun NFS, Ethernet, TCP/IP. Considering the heterogeneous nature of the present software (e.g., first started as an expert system using LISP machines) which now involve FORTRAN code, the effort is expected to be quite challenging.

  19. Ontogenic profiling of glucosinolates, flavonoids, and other secondary metabolites in Eruca sativa (salad rocket), Diplotaxis erucoides (wall rocket), Diplotaxis tenuifolia (wild rocket), and Bunias orientalis (Turkish rocket).

    Science.gov (United States)

    Bennett, Richard N; Rosa, Eduardo A S; Mellon, Fred A; Kroon, Paul A

    2006-05-31

    As an influence of the Mediterranean diet, rocket species such as Eruca sativa L., Diplotaxis species, and Bunias orientalis L. are eaten all over the world at different ontogenic stages in salads and soups. They are all species within the plant order Capparales (glucosinolate-containing species), and all are from the family Brassicaceae. Predominantly, the leaves of these species are eaten raw or cooked, although Eruca flowers are also consumed. There is considerable potential with raw plant material for a higher exposure to bioactive phytochemicals such as glucosinolates, their hydrolysis products, and also phenolics, flavonoids, and vitamins such as vitamin C. These compounds are susceptible to ontogenic variation, and the few published studies that have addressed this topic have been inconsistent. Thus, an ontogenic study was performed and all samples were analyzed using a previously developed robust liquid chromatography/mass spectrometry method for the identification and quantification of the major phytochemicals in all tissues of the rocket species. Seeds and roots of both Eruca and Diplotaxis contained predominantly 4-methylthiobutylglucosinolate. Leaves of Eruca and Diplotaxis contained high amounts of 4-mercaptobutylglucosinolate with lower levels of 4-methylthiobutlyglucosinolate and 4-methylsulfinylbutylglucosinolate. Flowers of Eruca and Diplotaxiscontained predominantly 4-methylsulfinylbutyl-glucosinolate. In addition, roots of both Diplotaxisspecies contained 4-hydroxybenzylglucosinolate but 4-hydroxybenzylglucosinolate was absent from roots of Eruca. Seeds and seedlings of all Eruca contained N-heterocyclic compounds but no sinapine, whereas Diplotaxis contained sinapine but not the N-heterocycles. In all tissues of B. orientalis, 4-hydroxybenzylglucosinolate and 4-methylsulfinyl-3-butenylglucosinolate were predominant. All rocket tissues, except roots, contained significant levels of polyglycosylated flavonoids, with/without hydroxycinnamoyl

  20. Lyman alpha coronagraph research sounding rocket program

    Science.gov (United States)

    Parkinson, W. H.; Kohl, J. L.

    1985-01-01

    The ultraviolet light coronagraph was developed and successfully flown on three rocket flights on 13 April 1979, 16 February 1980 and 20 July 1982. During each of these flights, the Ultraviolet Light Coronagraph was flown jointly with the White Light Coronagraph provided by the High Altitude Observatory. Ultraviolet diagnostic techniques and instrumentation for determining the basic plasma parameters of solar wind acceleration regions in the extended corona were developed and verified and the understanding of the physics of the corona through the performance, analysis and interpretation of solar observations advanced. Valuable UV diagnostics can be performed in the absence of a natural solar eclipse.

  1. Rocket-Powered Parachutes Rescue Entire Planes

    Science.gov (United States)

    2010-01-01

    Small Business Innovation Research (SBIR) contracts with Langley Research Center helped BRS Aerospace, of Saint Paul, Minnesota, to develop technology that has saved 246 lives to date. The company s whole aircraft parachute systems deploy in less than 1 second thanks to solid rocket motors and are capable of arresting the descent of a small aircraft, lowering it safely to the ground. BRS has sold more than 30,000 systems worldwide, and the technology is now standard equipment on many of the world s top-selling aircraft. Parachutes for larger airplanes are in the works.

  2. Nuclear thermal rocket engine operation and control

    Science.gov (United States)

    Gunn, Stanley V.; Savoie, Margarita T.; Hundal, Rolv

    1993-06-01

    The operation of a typical Rover/Nerva-derived nuclear thermal rocket (NTR) engine is characterized and the control requirements of the NTR are defined. A rationale for the selection of a candidate diverse redundant NTR engine control system is presented and the projected component operating requirements are related to the state of the art of candidate components and subsystems. The projected operational capabilities of the candidate system are delineated for the startup, full-thrust, shutdown, and decay heat removal phases of the engine operation.

  3. Water Rockets. Get Funny With Newton's Laws

    Directory of Open Access Journals (Sweden)

    Manuel Roca Vicent

    2017-01-01

    Full Text Available The study of the movement of the rocket has been used for decades to encourage students in the study of physics. This system has an undeniable interest to introduce concepts such as properties of gases, laws of Newton,  exchange  between  different  types  of  energy  and  its  conservation  or fluid  mechanics.  Our  works has  been  to  build  and  launch  these  rockets  in  different  educational  levels  and  in  each  of  these  ones  have introduced  the  part  of  Physics  more  suited  to  the  knowledge  of  our  students.  The  aim  of  the  learning experience  is  to  launch  the  rocket  as  far  as  possible  and  learn  to  predict  the  travelled  distance,  using Newton's  laws  and fluid  mechanics.  After  experimentation  we  demonstrated  to  be  able  to  control  the parameters that improve the performance of our rocket, such as the  fill factor, the volume and mass of the empty  bottle,  liquid  density,  launch  angle,  pressure  prior  air  release.  In addition, it is a fun experience can be attached to all levels of education in primary and high school.

  4. Air expansion in the water rocket

    CERN Document Server

    Romanelli, Alejandro; Madina, Federico González

    2012-01-01

    We study the thermodynamics of the water rocket in the thrust phase, taking into account the expansion of the air with water vapor, vapor condensation and the energy taken from the environment. We set up a simple experimental device with a stationary bottle and verified that the gas expansion in the bottle is well approximated by a polytropic process $PV^\\beta$= constant, where the parameter $\\beta$ depends on the initial conditions. We find an analytical expression for $\\beta $ that only depends on the thermodynamic initial conditions and is in good agreement with the experimental results.

  5. Analysis of a Radioisotope Thermal Rocket Engine

    Science.gov (United States)

    Machado-Rodriguez, Jonathan P.; Landis, Geoffrey A.

    2017-01-01

    The Triton Hopper is a concept for a vehicle to explore the surface of Neptunes moon Triton, which uses a radioisotope heated rocket engine and in-situ propellant acquisition. The initial Triton Hopper conceptual design stores pressurized Nitrogen in a spherical tank to be used as the propellant. The aim of the research was to investigate the benefits of storing propellant at ambient temperature and heating it through a thermal block during engine operation, as opposed to storing gas at a high temperature.

  6. Computational Analysis for Rocket-Based Combined-Cycle Systems During Rocket-Only Operation

    Science.gov (United States)

    Steffen, C. J., Jr.; Smith, T. D.; Yungster, S.; Keller, D. J.

    2000-01-01

    A series of Reynolds-averaged Navier-Stokes calculations were employed to study the performance of rocket-based combined-cycle systems operating in an all-rocket mode. This parametric series of calculations were executed within a statistical framework, commonly known as design of experiments. The parametric design space included four geometric and two flowfield variables set at three levels each, for a total of 729 possible combinations. A D-optimal design strategy was selected. It required that only 36 separate computational fluid dynamics (CFD) solutions be performed to develop a full response surface model, which quantified the linear, bilinear, and curvilinear effects of the six experimental variables. The axisymmetric, Reynolds-averaged Navier-Stokes simulations were executed with the NPARC v3.0 code. The response used in the statistical analysis was created from Isp efficiency data integrated from the 36 CFD simulations. The influence of turbulence modeling was analyzed by using both one- and two-equation models. Careful attention was also given to quantify the influence of mesh dependence, iterative convergence, and artificial viscosity upon the resulting statistical model. Thirteen statistically significant effects were observed to have an influence on rocket-based combined-cycle nozzle performance. It was apparent that the free-expansion process, directly downstream of the rocket nozzle, can influence the Isp efficiency. Numerical schlieren images and particle traces have been used to further understand the physical phenomena behind several of the statistically significant results.

  7. Cloud Climatologies for Rocket Triggered Lightning from Launches at Cape Canaveral Air Force Station and Kennedy Space Center

    Science.gov (United States)

    2012-03-01

    6  Figure 4.  Map indicating five nautical mile ring around the average launch site (light yellow...as a temperature constraint, a wind direction and speed limitation, to potential for lightning occurrence, or a specific cloud formation surrounding...meteorological conditions near the site of the Apollo XII incident (From: Merceret et al. 2010) As the Saturn V rocket with the manned space capsule ascended

  8. Monitoring the endangered population of the antelope Kobus leche smithemani (Artiodactyla: Bovidae, in the Bangweulu ecosystem, Zambia

    Directory of Open Access Journals (Sweden)

    Victor M. Siamudaala

    2012-12-01

    Full Text Available Black lechwe (Kobus leche smithemani is a semi-aquatic medium sized antelope currently enlisted on the IUCN red list of endangered species and is only endemic to the Bangweulu basin of Zambia. Its population has significantly decreased due to floods that took place during the period 1930-1940 from over 250 000-15 000 leading the Zambian government to gazette all habitats of Black lechwe into state protected areas, and to establish urgent management strategies needed to save the remaining population from extinction. Using retrospective data, our findings show that the population has increased from 15 000 animals in 1954 to 55 632 in 2009. The current population is estimated at 34.77% (55 632/160 000 of the carrying capacity of the Bangweulu basin. Although the Black lechwe is one of the 42 species offered for consumptive utilization by the Zambia Wildlife Authority (ZAWA, only 0.12% and 0.08% of the current stock was offered for safari and resident hunting annually for the period 2005-2009, respectively. Annual quota utilization were estimated at 67% (n=37 and 81% (n=37 for safari and resident hunting, respectively. Hence, overall income obtained from utilization of Black lechwe is very low accounting for only 2.1% of the total revenue earned from wildlife utilization. Although the current population trend is showing a unit increase of 639 animals per year, it is still far below levels ideal for the lucrative utilization. In this study, we demonstrate that adverse ecological changes on wildlife species, can lead to their vulnerability and danger of extinction, and that their recovery to full carrying capacity may demand a considerable amount of timeEl lechwe negro (Kobus leche smithemani es un antílope semi-acuático de tamaño medio que en la actualidad se encuentra en la lista roja de la UICN de especies en peligro de extinción y sólo es endémica de la cuenca del Bangweulu de Zambia. Su población ha disminuido considerablemente, de más de

  9. The Geminid meteor shower during the ECOMA sounding rocket campaign: specular and head echo radar observations

    Directory of Open Access Journals (Sweden)

    G. Stober

    2013-03-01

    Full Text Available The ECOMA (Existence of Charge state Of meteoric smoke particles in the Middle Atmosphere sounding rocket campaign was conducted during the Geminid meteor shower in December 2010 in order to explore whether there is a change of the properties of meteoric smoke particles due to the stream. In parallel to the rocket flights, three radars monitored the Geminid activity located at the launch site in Northern Norway and in Northern Germany to gain information about the meteor flux into the atmosphere. The results presented here are based on specular meteor radar observations measuring the radiant position, the velocity and the meteor flux into the atmosphere during the Geminids. Further, the MAARSY (Middle Atmosphere Alomar Radar System radar was operated to conduct meteor head echo experiments. The interferometric capabilities of MAARSY permit measuring the meteor trajectories within the radar beam and to determine the source radiant and geocentric meteor velocity, as well as to compute the meteor orbit.

  10. The Chameleon Solid Rocket Propulsion Model

    Science.gov (United States)

    Robertson, Glen A.

    2010-01-01

    The Khoury and Weltman (2004a and 2004b) Chameleon Model presents an addition to the gravitation force and was shown by the author (Robertson, 2009a and 2009b) to present a new means by which one can view other forces in the Universe. The Chameleon Model is basically a density-dependent model and while the idea is not new, this model is novel in that densities in the Universe to include the vacuum of space are viewed as scalar fields. Such an analogy gives the Chameleon scalar field, dark energy/dark matter like characteristics; fitting well within cosmological expansion theories. In respect to this forum, in this paper, it is shown how the Chameleon Model can be used to derive the thrust of a solid rocket motor. This presents a first step toward the development of new propulsion models using density variations verse mass ejection as the mechanism for thrust. Further, through the Chameleon Model connection, these new propulsion models can be tied to dark energy/dark matter toward new space propulsion systems utilizing the vacuum scalar field in a way understandable by engineers, the key toward the development of such systems. This paper provides corrections to the Chameleon rocket model in Robertson (2009b).

  11. Software for Collaborative Engineering of Launch Rockets

    Science.gov (United States)

    Stanley, Thomas Troy

    2003-01-01

    The Rocket Evaluation and Cost Integration for Propulsion and Engineering software enables collaborative computing with automated exchange of information in the design and analysis of launch rockets and other complex systems. RECIPE can interact with and incorporate a variety of programs, including legacy codes, that model aspects of a system from the perspectives of different technological disciplines (e.g., aerodynamics, structures, propulsion, trajectory, aeroheating, controls, and operations) and that are used by different engineers on different computers running different operating systems. RECIPE consists mainly of (1) ISCRM a file-transfer subprogram that makes it possible for legacy codes executed in their original operating systems on their original computers to exchange data and (2) CONES an easy-to-use filewrapper subprogram that enables the integration of legacy codes. RECIPE provides a tightly integrated conceptual framework that emphasizes connectivity among the programs used by the collaborators, linking these programs in a manner that provides some configuration control while facilitating collaborative engineering tradeoff studies, including design to cost studies. In comparison with prior collaborative-engineering schemes, one based on the use of RECIPE enables fewer engineers to do more in less time.

  12. Physiological and phytosanitary potential of rocket seeds

    Directory of Open Access Journals (Sweden)

    Jucilayne Fernandes Vieira

    2015-02-01

    Full Text Available The objective of this study was to evaluate the physiological and sanitary quality of seeds of rocket; the research was done at the Laboratory of Seed Analysis and greenhouse of the Department of Plant Science, Federal University of Pelotas (UFPel. Four lots of the cultivar "Antonella'' were tested for following features: initial and final moisture content, germination rate, first count of germination, accelerated aging with saline solution, dry matter contents, seedling shoot and root length, emergence speed index, emergence of seedlings in substrate, electrical conductivity and sanitary condition. A completely randomized design with four replications was used for all tests done and means were compared by Tukey test (P≤0.05. For all tests performed it was concluded that despite changes in the ranking of the best lots, there was agreement regarding the indication of the inferiority of the lot 3 in all tests and it was also observed that the incidence of fungi associated with seeds of rocket interfere with the physiological quality of the lots.

  13. Computational simulation of liquid fuel rocket injectors

    Science.gov (United States)

    Landrum, D. Brian

    1994-01-01

    A major component of any liquid propellant rocket is the propellant injection system. Issues of interest include the degree of liquid vaporization and its impact on the combustion process, the pressure and temperature fields in the combustion chamber, and the cooling of the injector face and chamber walls. The Finite Difference Navier-Stokes (FDNS) code is a primary computational tool used in the MSFC Computational Fluid Dynamics Branch. The branch has dedicated a significant amount of resources to development of this code for prediction of both liquid and solid fuel rocket performance. The FDNS code is currently being upgraded to include the capability to model liquid/gas multi-phase flows for fuel injection simulation. An important aspect of this effort is benchmarking the code capabilities to predict existing experimental injection data. The objective of this MSFC/ASEE Summer Faculty Fellowship term was to evaluate the capabilities of the modified FDNS code to predict flow fields with liquid injection. Comparisons were made between code predictions and existing experimental data. A significant portion of the effort included a search for appropriate validation data. Also, code simulation deficiencies were identified.

  14. Nuclear Thermal Rocket Simulation in NPSS

    Science.gov (United States)

    Belair, Michael L.; Sarmiento, Charles J.; Lavelle, Thomas M.

    2013-01-01

    Four nuclear thermal rocket (NTR) models have been created in the Numerical Propulsion System Simulation (NPSS) framework. The models are divided into two categories. One set is based upon the ZrC-graphite composite fuel element and tie tube-style reactor developed during the Nuclear Engine for Rocket Vehicle Application (NERVA) project in the late 1960s and early 1970s. The other reactor set is based upon a W-UO2 ceramic-metallic (CERMET) fuel element. Within each category, a small and a large thrust engine are modeled. The small engine models utilize RL-10 turbomachinery performance maps and have a thrust of approximately 33.4 kN (7,500 lbf ). The large engine models utilize scaled RL-60 turbomachinery performance maps and have a thrust of approximately 111.2 kN (25,000 lbf ). Power deposition profiles for each reactor were obtained from a detailed Monte Carlo N-Particle (MCNP5) model of the reactor cores. Performance factors such as thermodynamic state points, thrust, specific impulse, reactor power level, and maximum fuel temperature are analyzed for each engine design.

  15. Liquid fuel injection elements for rocket engines

    Science.gov (United States)

    Cox, George B., Jr. (Inventor)

    1993-01-01

    Thrust chambers for liquid propellant rocket engines include three principal components. One of these components is an injector which contains a plurality of injection elements to meter the flow of propellants at a predetermined rate, and fuel to oxidizer mixture ratio, to introduce the mixture into the combustion chamber, and to cause them to be atomized within the combustion chamber so that even combustion takes place. Evolving from these injectors are tube injectors. These tube injectors have injection elements for injecting the oxidizer into the combustion chamber. The oxidizer and fuel must be metered at predetermined rates and mixture ratios in order to mix them within the combustion chamber so that combustion takes place smoothly and completely. Hence tube injectors are subject to improvement. An injection element for a liquid propellant rocket engine of the bipropellant type is provided which includes tangential fuel metering orifices, and a plurality of oxidizer tube injection elements whose injection tubes are also provided with tangential oxidizer entry slots and internal reed valves.

  16. Characterization of nal powders for rocket propulsion

    Science.gov (United States)

    Merotto, L.; Galfetti, L.; Colombo, G.; DeLuca, L. T.

    2011-10-01

    Nanosized metal powders are known to significantly improve both solid and hybrid rocket performance, but have some drawbacks in terms of cost, safety, and possible influence on propellant mechanical properties. Performance enhancement through nanosized metal or metal hydride addition to solid fuels is currently under investigation also for hybrid propulsion. Therefore, a preburning characterization of the powders used in solid propellant or fuel manufacturing is useful to assess their effects on the ballistic properties and engine performance. An investigation concerning the comparative characterization of several aluminum powders having different particle size, age, and coating is presented. Surface area, morphology, chemical species concentration and characteristics, surface passivation layers, surface and subsurface chemical composition, ignition temperature and ignition delay are investigated. The aim of this characterization is to experimentally assess the effect of the nAl powder properties on ballistic characteristics of solid fuels and solidrocket composite-propellant performance, showing an increase in terms of Is caused by the decrease of two-phase losses in solid and a possible significant rf increase in hybrid rockets.

  17. Solid Rocket Launch Vehicle Explosion Environments

    Science.gov (United States)

    Richardson, E. H.; Blackwood, J. M.; Hays, M. J.; Skinner, T.

    2014-01-01

    Empirical explosion data from full scale solid rocket launch vehicle accidents and tests were collected from all available literature from the 1950s to the present. In general data included peak blast overpressure, blast impulse, fragment size, fragment speed, and fragment dispersion. Most propellants were 1.1 explosives but a few were 1.3. Oftentimes the data from a single accident was disjointed and/or missing key aspects. Despite this fact, once the data as a whole was digitized, categorized, and plotted clear trends appeared. Particular emphasis was placed on tests or accidents that would be applicable to scenarios from which a crew might need to escape. Therefore, such tests where a large quantity of high explosive was used to initiate the solid rocket explosion were differentiated. Also, high speed ground impacts or tests used to simulate such were also culled. It was found that the explosions from all accidents and applicable tests could be described using only the pressurized gas energy stored in the chamber at the time of failure. Additionally, fragmentation trends were produced. Only one accident mentioned the elusive "small" propellant fragments, but upon further analysis it was found that these were most likely produced as secondary fragments when larger primary fragments impacted the ground. Finally, a brief discussion of how this data is used in a new launch vehicle explosion model for improving crew/payload survival is presented.

  18. Advanced materials for radiation-cooled rockets

    Science.gov (United States)

    Reed, Brian; Biaglow, James; Schneider, Steven

    1993-01-01

    The most common material system currently used for low thrust, radiation-cooled rockets is a niobium alloy (C-103) with a fused silica coating (R-512A or R-512E) for oxidation protection. However, significant amounts of fuel film cooling are usually required to keep the material below its maximum operating temperature of 1370 C, degrading engine performance. Also the R-512 coating is subject to cracking and eventual spalling after repeated thermal cycling. A new class of high-temperature, oxidation-resistant materials are being developed for radiation-cooled rockets, with the thermal margin to reduce or eliminate fuel film cooling, while still exceeding the life of silicide-coated niobium. Rhenium coated with iridium is the most developed of these high-temperature materials. Efforts are on-going to develop 22 N, 62 N, and 440 N engines composed of these materials for apogee insertion, attitude control, and other functions. There is also a complimentary NASA and industry effort to determine the life limiting mechanisms and characterize the thermomechanical properties of these materials. Other material systems are also being studied which may offer more thermal margin and/or oxidation resistance, such as hafnium carbide/tantalum carbide matrix composites and ceramic oxide-coated iridium/rhenium chambers.

  19. Pathology and immunohistochemistry of papillomavirus-associated cutaneous lesions in Cape mountain zebra, giraffe, sable antelope and African buffalo in South Africa

    Directory of Open Access Journals (Sweden)

    J. H. Williams

    2011-04-01

    Full Text Available Skin lesions associated with papillomaviruses have been reported in many animal species and man. Bovine papillomavirus (BVP affects mainly the epidermis, but also the dermis in several species including bovine, the best-known example being equine sarcoid, which is associated with BVP types 1 and 2. This publication describes and illustrates the macroscopic and histological appearance of BPV-associated papillomatous, fibropapillomatous or sarcoid-like lesions in Cape mountain zebra (Equus zebra zebra from the Gariep Dam Nature Reserve, 2 giraffes (Giraffa camelopardalis from the Kruger National Park, and a sable antelope (Hippotragus niger from the Kimberley area of South Africa. An African buffalo (Syncerus caffer cow from Kruger National Park also had papillomatous lesions but molecular characterisation of lesional virus was not done. Immunohistochemical staining using polyclonal rabbit antiserum to chemically disrupted BPV-1, which cross-reacts with the L1 capsid of most known papillomaviruses, was positive in cells of the stratum granulosum of lesions in Giraffe 1, the sable and the buffalo and negative in those of the zebra and Giraffe 2. Fibropapillomatous and sarcoid-like lesions from an adult bovine were used as positive control for the immunohistochemistry and are described and the immunohistochemistry illustrated for comparison. Macroscopically, both adult female giraffe had severely thickened multifocal to coalescing nodular and occasionally ulcerated lesions of the head, neck and trunk with local poorly-circumscribed invasion into the subcutis. Necropsy performed on the 2nd giraffe revealed neither internal metastases nor serious underlying disease. Giraffe 1 had scattered, and Giraffe 2 numerous, large, anaplastic, at times indistinctly multinucleated dermal fibroblasts with bizarre nuclei within the sarcoid-like lesions, which were BPV-1 positive in Giraffe 1 and BPV-1 and -2 positive in Giraffe 2 by RT-PCR. The sable antelope

  20. SM1.3 Seismic Centers Data Acquisition: an introduction to Antelope, EarthWorm, SeisComP and their usage around the world

    Science.gov (United States)

    Pesaresi, Damiano; Sleeman, Reinoud

    2010-05-01

    Many medium to big size seismic data centers around the world are facing the same question: which software to use to acquire seismic data in real-time? A home-made or a commercial one? Both choices have pros and cons. The in-house development of software usually requires an increased investment in human resources rather than a financial investment. However, the advantage of fully accomplishing your own needs could be put in danger when the software engineer quits the job! Commercial software offers the advantage of being maintained, but it may require both a considerable financial investment and training. The main seismic software data acquisition suites available nowadays are the public domain SeisComP and EarthWorm packages and the commercial package Antelope. Nanometrics, Guralp and RefTek also provide seismic data acquisition software, but they are mainly intended for single station/network acquisition. Antelope is a software package for real-time acquisition and processing of seismic network data, with its roots in the academic seismological community. The software is developed by Boulder Real Time Technology (BRTT) and commercialized by Kinemetrics. It is used by IRIS affiliates for off-line data processing and it is the main acquisition tool for the USArray program and data centers in Europe like the ORFEUS Data Center, OGS (Italy), ZAMG (Austria), ARSO (Slovenia) and GFU (Czech Republic). SeisComP was originally developed for the GEOFON global network to provide a system for data acquisition, data exchange (SeedLink protocol) and automatic processing. It has evolved into to a widely distributed, networked seismographic system for data acquisition and real-time data exchange over Internet and is supported by ORFEUS as the standard seismic data acquisition tool in Europe. SeisComP3 is the next generation of the software and was developed for the German Indonesian Tsunami Early Warning System (GITEWS). SeisComP is licensed by GFZ (free of charge) and

  1. Effects of Rocket Exhaust on Lunar Soil Reflectance Properties

    Science.gov (United States)

    Clegg, R. N.; Jolliff, B. L.; Robinson, M. S.; Hapke, B. W.; Plescia, J. B.

    2012-12-01

    The Apollo, Surveyor, and Luna spacecraft descent engine plumes affected the regolith at and surrounding their landing sites. Owing to the lack of rapid weathering processes on the Moon, surface alterations are still visible as photometric anomalies in Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images. These areas are interpreted as disturbance of the regolith by rocket exhaust during descent of the spacecraft, which we refer to as "blast zones" (BZs). The BZs consist of an area of lower reflectance (LR-BZ) compared to the surroundings that extends up to a few meters out from the landers, as well as a broader halo of higher reflectance (HR-BZ) that extends tens to hundreds of meters out from the landers. We use phase-ratio images for each landing site to determine the spatial extent of the disturbed regions and to quantify differences in reflectance and backscattering characteristics within the BZs compared to nearby undisturbed regolith. We also compare the reflectance changes and BZ dimensions at the Apollo sites with those at Luna and Surveyor sites. We seek to determine the effects of rocket exhaust in terms of erosion and particle redistribution, as well as the cause(s) of the reflectance variations, i.e., physical changes at the regolith surface. When approximated as an ellipse, the average Apollo BZ area is ~29,000 m2 (~175 ± 60 m by 200 ± 27 m) which is 10x larger than the average Luna BZ, and over 100x larger than the average Surveyor BZ. Moreover, BZ area scales roughly with lander mass (as a proxy for thrust). The LR-BZs are evident at the Apollo sites, especially where astronaut bioturbation has roughened the soil, leading to a 2-14% reduction in reflectance at ~30° phase. The LR-BZs at the Luna and Surveyor sites are less evident and may be mostly confined to the area below the landers. The average normalized reflectance in the HR-BZs for images with a 30° phase angle is 2-16% higher than in the undisturbed surrounding

  2. Project Stratos; reaching space with a student-built rocket

    NARCIS (Netherlands)

    Haneveer, M.

    2013-01-01

    In the spring of 2009 a team of 15 TU Delft students travelled to Kiruna, Sweden with only one goal: to launch the rocket Stratos I they had been working on for 2 years to an altitude of over 12km, thereby claiming the European Amateur Rocket Altitude record. These students were part of Delft

  3. Project Stratos; reaching space with a student-built rocket

    NARCIS (Netherlands)

    Haneveer, M.

    2013-01-01

    In the spring of 2009 a team of 15 TU Delft students travelled to Kiruna, Sweden with only one goal: to launch the rocket Stratos I they had been working on for 2 years to an altitude of over 12km, thereby claiming the European Amateur Rocket Altitude record. These students were part of Delft Aerosp

  4. Sounding rocket experiment of bare electrodynamic tether system

    OpenAIRE

    Fujii, Hironori; Watanabe, Takeo; Kojima, Hirohisa; OYAMA, Koh-ichiro; Kusagaya, Tairo; Yamagiwa, Yoshiki; Ohtsu, Hirotaka; Cho, Mengu; Sasaki, Susumu; Tanaka, Koji; Williams, John; Rubin, Binyamin; Les Jhonson, Charles; Khazanov, George; Sanmartín Losada, Juan Ramón

    2009-01-01

    An overview of asounding rocket S-520-25th, project on space tether technology experiment is presented.The project is prepared by an international research group consisting of Japanese,European,American,andAustralianresearchers.The sounding rocket will be assembled by the ISAS/JAXA and will be launched in the summer of 2009.

  5. The Effect of Atmospheric Pressure on Rocket Thrust -- Part I.

    Science.gov (United States)

    Leitner, Alfred

    1982-01-01

    The first of a two-part question asks: Does the total thrust of a rocket depend on the surrounding pressure? The answer to this question is provided, with accompanying diagrams of rockets. The second part of the question (and answer) are provided in v20 n7, p479, Oct 1982 of this journal. (Author/JN)

  6. Some cases of vertical ascent of a rocket

    Directory of Open Access Journals (Sweden)

    M. Narsing Rao

    1960-07-01

    Full Text Available The differential equations of motion of vertically ascending rocket are integrated in closed form in terms of Bessel functions. During burning the drag co-efficient and acceleration due to gravity are assumed to be constant. Four different cases of motion are treated under different assumptions regarding the law of mass-variations of the rocket.

  7. Developments in REDES: The Rocket Engine Design Expert System

    Science.gov (United States)

    Davidian, Kenneth O.

    1990-01-01

    The Rocket Engine Design Expert System (REDES) was developed at NASA-Lewis to collect, automate, and perpetuate the existing expertise of performing a comprehensive rocket engine analysis and design. Currently, REDES uses the rigorous JANNAF methodology to analyze the performance of the thrust chamber and perform computational studies of liquid rocket engine problems. The following computer codes were included in REDES: a gas properties program named GASP; a nozzle design program named RAO; a regenerative cooling channel performance evaluation code named RTE; and the JANNAF standard liquid rocket engine performance prediction code TDK (including performance evaluation modules ODE, ODK, TDE, TDK, and BLM). Computational analyses are being conducted by REDES to provide solutions to liquid rocket engine thrust chamber problems. REDES was built in the Knowledge Engineering Environment (KEE) expert system shell and runs on a Sun 4/110 computer.

  8. Introduction to the Special Issue on Sounding Rockets and Instrumentation

    CERN Document Server

    Christe, Steven; Pfaff, Rob; Garcia, Michael

    2016-01-01

    Rocket technology, originally developed for military applications, has provided a low-cost observing platform to carry critical and rapid-response scientific investigations for over 70 years. Even with the development of launch vehicles that could put satellites into orbit, high altitude sounding rockets have remained relevant. In addition to science observations, sounding rockets provide a unique technology test platform and a valuable training ground for scientists and engineers. Most importantly, sounding rockets remain the only way to explore the tenuous regions of the Earth's atmosphere (the upper stratosphere, mesosphere, and lower ionosphere/thermosphere) above balloon altitudes ($\\sim$40 km) and below satellite orbits ($\\sim$160 km). They can lift remote sensing telescope payloads with masses up to 400 kg to altitudes of 350 km providing observing times of up to 6 minutes above the blocking influence of Earth's atmosphere. Though a number of sounding rocket research programs exist around the world, th...

  9. Development of high performance hybrid rocket fuels

    Science.gov (United States)

    Zaseck, Christopher R.

    In this document I discuss paraffin fuel combustion and investigate the effects of additives on paraffin entrainment and regression. In general, hybrid rockets offer an economical and safe alternative to standard liquid and solid rockets. However, slow polymeric fuel regression and low combustion efficiency have limited the commercial use of hybrid rockets. Paraffin is a fast burning fuel that has received significant attention in the 2000's and 2010's as a replacement for standard fuels. Paraffin regresses three to four times faster than polymeric fuels due to the entrainment of a surface melt layer. However, further regression rate enhancement over the base paraffin fuel is necessary for widespread hybrid rocket adoption. I use a small scale opposed flow burner to investigate the effect of additives on the combustion of paraffin. Standard additives such as aluminum combust above the flame zone where sufficient oxidizer levels are present. As a result no heat is generated below the flame itself. In small scale opposed burner experiments the effect of limited heat feedback is apparent. Aluminum in particular does not improve the regression of paraffin in the opposed burner. The lack of heat feedback from additive combustion limits the applicability of the opposed burner. In turn, the results obtained in the opposed burner with metal additive loaded hybrid fuels do not match results from hybrid rocket experiments. In addition, nano-scale aluminum increases melt layer viscosity and greatly slows the regression of paraffin in the opposed flow burner. However, the reactive additives improve the regression rate of paraffin in the opposed burner where standard metals do not. At 5 wt.% mechanically activated titanium and carbon (Ti-C) improves the regression rate of paraffin by 47% in the opposed burner. The mechanically activated Ti C likely reacts in or near the melt layer and provides heat feedback below the flame region that results in faster opposed burner regression

  10. Telemaxus: A telescience oriented sounding rocket experiment

    Science.gov (United States)

    Monti, R.; Fortezza, R.; Desiderio, G.; Capuano, G.; Titomanlio, D.

    Following the success of the Texus 23 Campaign (November 1989), during which the Teletexus experiment was conducted a more ambitious Telescience experiment was accomodated on the 1991 MAXUS 1 Payload. The fluidynamic experiment on the oscillatory Marangoni flow was performed on board the rocket (launched at Kiruna, Sweden) using a modified TEM-06/4 module. The experiment was fully controlled by the PI (Professor Monti) directly from the Telescience Control Room located at MARS Center (Naples, Italy). The experiment was also aimed to demonstrate the capabilities of Telescience Service that ESA offers to the European Microgravity User Community. Respect to other experiments already tested and assessed during previous Texus missions (14b, 23), the Telescience operation mode included new state-of-art technologies and subsystems to demonstrate capabilities, flexibility and usefulness of this operation concept mainly in the perspective of Columbus utilization. Unfortunately due to a failure of the rocket system, the microgravity condition was not reached during the flight and the fluidynamic results were missed. However, in spite of the tumbling attitude of the rocket, the telescience link was successfully tested and the video/data/audio communication was correctly established between MARS and Esrange. This paper illustrates the technological aspects and gives an overview of the systems/equipments integrated and realized for the experiment control. In the first part the H/W configurations for the experiment monitoring and control, identified by the research team are illustrated. The relevant items of the H/W configuration include: the Telescience Work Stations architecture, the link channels used for the selection, transmission and reception of video/data/commands and the subsystems manufactured to improve the system versatility. The second part deals with the communication link used for transmission between Sweden and Italy of experimental data, facility status, voice

  11. Rocket Engine Innovations Advance Clean Energy

    Science.gov (United States)

    2012-01-01

    During launch countdown, at approximately T-7 seconds, the Space Shuttle Main Engines (SSMEs) roar to life. When the controllers indicate normal operation, the solid rocket boosters ignite and the shuttle blasts off. Initially, the SSMEs throttle down to reduce stress during the period of maximum dynamic pressure, but soon after, they throttle up to propel the orbiter to 17,500 miles per hour. In just under 9 minutes, the three SSMEs burn over 1.6 million pounds of propellant, and temperatures inside the main combustion chamber reach 6,000 F. To cool the engines, liquid hydrogen circulates through miles of tubing at -423 F. From 1981to 2011, the Space Shuttle fleet carried crew and cargo into orbit to perform a myriad of unprecedented tasks. After 30 years and 135 missions, the feat of engineering known as the SSME boasted a 100-percent flight success rate.

  12. Characterization of rocket propellant combustion products

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, R.A.; Nestor, C.W.; Thompson, C.V.; Gayle, T.M.; Ma, C.Y.; Tomkins, B.A.; Moody, R.L.

    1991-12-09

    The overall objective of the work described in this report is four-fold: to (a) develop a standardized and experimentally validated approach to the sampling and chemical and physical characterization of the exhaust products of scaled-down rocket launch motors fired under experimentally controlled conditions at the Army's Signature Characterization Facility (ASCF) at Redstone Arsenal in Huntsville, Alabama; (b) determine the composition of the exhaust produces; (c) assess the accuracy of a selected existing computer model for predicting the composition of major and minor chemical species; (d) recommended alternations to both the sampling and analysis strategy and the computer model in order to achieve greater congruence between chemical measurements and computer prediction. 34 refs., 2 figs., 35 tabs.

  13. Lunar mission design using Nuclear Thermal Rockets

    Science.gov (United States)

    Stancati, Michael L.; Collins, John T.; Borowski, Stanley K.

    1991-01-01

    The NERVA-class Nuclear Thermal Rocket (NTR), with performance nearly double that of advanced chemical engines, has long been considered an enabling technology for human missions to Mars. NTR engines address the demanding trip time and payload delivery needs of both cargo-only and piloted flights. But NTR can also reduce the Earth launch requirements for manned lunar missions. First use of NTR for the Moon would be less demanding and would provide a test-bed for early operations experience with this powerful technology. Study of application and design options indicates that NTR propulsion can be integrated with the Space Exploration Initiative scenarios to deliver performance gains while managing controlled, long-term disposal of spent reactors to highly stable orbits.

  14. Electronic timer for sounding rocket payload use

    Science.gov (United States)

    Williams, C. P.

    1986-01-01

    An electronic timer has been developed for sounding rocket use. The timer uses CMOS technology for low power consumption and has a battery back-up to keep the timing circuit active in case of a dropout on the payload power bus. Time-event decoding is done by programming EPROM's which enable a +28 volt dc sourcing output. There are 32 discrete outputs which can provide +28 volt dc into a minimum load impedance of 150 ohms. Inputs are designed to operate on standard CMOS voltage levels, but they can withstand +28 volts dc without damage. The timer can be started by either 'G' or lift-off switch closure or umbilical release at lift-off.

  15. Innovative Metallized Formulations for Solid Rocket Propulsion

    Institute of Scientific and Technical Information of China (English)

    Luigi T DeLUCA; Luciano GALFETTI; Filippo MAGGI; Giovanni COLOMBO; Alice REINA; Stefano DOSSI; Daniele CONSONNI; Melissa BRAMBILLA

    2012-01-01

    Several metallized solid rocket propellants,AP/Metal/HTPB in the ratio 68/18/1 4,were experimentally analyzed at the Space Propulsion Laboratory of Politecnico di Milano.Effects of the metals (micrometric and nanometric Al,B,Mg,and a variety of dual metals) on the performance of the propellant were studied and contrasted to a conventional micrometric aluminum (30 μm average grain size) taken as reference.It is shown that the propellant microstructure plays a fundamental role in controlling the critical aggregation/agglomeration phenomena occurring below and near the burning surface.Two specific effects of microstructure in terms of steady burning rate and average agglomerate size are illustrated.

  16. Integrated model of a composite propellant rocket

    Science.gov (United States)

    Miccio, Francesco

    2016-12-01

    The combustion of composite solid propellants was investigated and an available numerical model was improved for taking into account the change of pressure, when the process occurs in a confined environment, as inside a rocket. The pressure increase upon ignition is correctly described by the improved model for both sandwich and dispersed particles propellants. In the latter case, self-induced fluctuations in the pressure and in all other computed variables occur, as consequence of the periodic rise and depletion of oxidizer particles from the binder matrix. The comparison with the results of the constant pressure model shows a different fluctuating profile of gas velocity, with a possible second order effect induced by the pressure fluctuations.

  17. CFD Simulation of Liquid Rocket Engine Injectors

    Science.gov (United States)

    Farmer, Richard; Cheng, Gary; Chen, Yen-Sen; Garcia, Roberto (Technical Monitor)

    2001-01-01

    Detailed design issues associated with liquid rocket engine injectors and combustion chamber operation require CFD methodology which simulates highly three-dimensional, turbulent, vaporizing, and combusting flows. The primary utility of such simulations involves predicting multi-dimensional effects caused by specific injector configurations. SECA, Inc. and Engineering Sciences, Inc. have been developing appropriate computational methodology for NASA/MSFC for the past decade. CFD tools and computers have improved dramatically during this time period; however, the physical submodels used in these analyses must still remain relatively simple in order to produce useful results. Simulations of clustered coaxial and impinger injector elements for hydrogen and hydrocarbon fuels, which account for real fluid properties, is the immediate goal of this research. The spray combustion codes are based on the FDNS CFD code' and are structured to represent homogeneous and heterogeneous spray combustion. The homogeneous spray model treats the flow as a continuum of multi-phase, multicomponent fluids which move without thermal or velocity lags between the phases. Two heterogeneous models were developed: (1) a volume-of-fluid (VOF) model which represents the liquid core of coaxial or impinger jets and their atomization and vaporization, and (2) a Blob model which represents the injected streams as a cloud of droplets the size of the injector orifice which subsequently exhibit particle interaction, vaporization, and combustion. All of these spray models are computationally intensive, but this is unavoidable to accurately account for the complex physics and combustion which is to be predicted, Work is currently in progress to parallelize these codes to improve their computational efficiency. These spray combustion codes were used to simulate the three test cases which are the subject of the 2nd International Workshop on-Rocket Combustion Modeling. Such test cases are considered by

  18. Assumed PDF modeling in rocket combustor simulations

    Science.gov (United States)

    Lempke, M.; Gerlinger, P.; Aigner, M.

    2013-03-01

    In order to account for the interaction between turbulence and chemistry, a multivariate assumed PDF (Probability Density Function) approach is used to simulate a model rocket combustor with finite-rate chemistry. The reported test case is the PennState preburner combustor with a single shear coaxial injector. Experimental data for the wall heat flux is available for this configuration. Unsteady RANS (Reynolds-averaged Navier-Stokes) simulation results with and without the assumed PDF approach are analyzed and compared with the experimental data. Both calculations show a good agreement with the experimental wall heat flux data. Significant changes due to the utilization of the assumed PDF approach can be observed in the radicals, e. g., the OH mass fraction distribution, while the effect on the wall heat flux is insignificant.

  19. Liquid atomization by coaxial rocket injectors

    Science.gov (United States)

    Sankar, S. V.; Brena De La Rosa, A.; Isakovic, A.; Bachalo, W. D.

    1991-01-01

    The atomization characteristics of a scaled-down version of a coaxial rocket injector was investigated using a phase Doppler particle analyzer (PDPA). The injector was operated in the conventional mode with liquid being injected through its inner orifice and gas being injected through its outer annulus. The shearing action occurring at the liquid-gas interface causes the liquid jet to atomize. In this study, two different liquid-air systems, namely a water-air system and a liquid nitrogen-gaseous nitrogen system, were chosen for detailed investigation. This paper discusses the performance characteristics of the coaxial injector under different flow and geometric conditions. Specifically, the effects of injection gas pressure and the injector cavity size on variables such as the mean particle diameter, Sauter mean diameter, number density, volume flux, and velocity have been presented.

  20. Heat transfer in rocket combustion chambers

    Science.gov (United States)

    Anderson, P.; Cheng, G.; Farmer, R.

    1993-01-01

    Complexities of liquid rocket engine heat transfer which involve the injector faceplate and film cooled walls are being investigated by computational analysis. A conjugate heat transfer analysis was used to describe localized heating phenomena associated with particular injector configurations and film coolant flows. These components were analyzed, and the analyses verified when appropriate test data were available. The component analyses are being synthesized into an overall flowfield/heat transfer model. A Navier-Stokes flow solver, the FDNS code, was used to make the analyses. Particular attention was given to the representation of the thermodynamic properties of the fluid streams. Unit flow models of specific coaxial injector elements have been developed and are being used to describe the flame structure near the injector faceplate.

  1. Rockets: Physical science teacher's guide with activities

    Science.gov (United States)

    Vogt, Gregory L.; Rosenberg, Carla R. (Editor)

    1993-01-01

    This guide begins with background information sections on the history of rocketry, scientific principles, and practical rocketry. The sections on scientific principles and practical rocketry are based on Isaac Newton's three laws of motion. These laws explain why rockets work and how to make them more efficient. The background sections are followed with a series of physical science activities that demonstrate the basic science of rocketry. Each activity is designed to be simple and take advantage of inexpensive materials. Construction diagrams, materials and tools lists, and instructions are included. A brief discussion elaborates on the concepts covered in the activities and is followed with teaching notes and discussion questions. The guide concludes with a glossary of terms, suggested reading list, NASA educational resources, and an evaluation questionnaire with a mailer.

  2. Additive Manufacturing a Liquid Hydrogen Rocket Engine

    Science.gov (United States)

    Jones, Carl P.; Robertson, Elizabeth H.; Koelbl, Mary Beth; Singer, Chris

    2016-01-01

    Space Propulsion is a 5 day event being held from 2nd May to the 6th May 2016 at the Rome Marriott Park Hotel in Rome, Italy. This event showcases products like Propulsion sub-systems and components, Production and manufacturing issues, Liquid, Solid, Hybrid and Air-breathing Propulsion Systems for Launcher and Upper Stages, Overview of current programmes, AIV issues and tools, Flight testing and experience, Technology building blocks for Future Space Transportation Propulsion Systems : Launchers, Exploration platforms & Space Tourism, Green Propulsion for Space Transportation, New propellants, Rocket propulsion & global environment, Cost related aspects of Space Transportation propulsion, Modelling, Pressure-Thrust oscillations issues, Impact of new requirements and regulations on design etc. in the Automotive, Manufacturing, Fabrication, Repair & Maintenance industries.

  3. Rocket observations of the diffuse ultraviolet background

    Science.gov (United States)

    Jakobsen, P.; Bowyer, S.; Kimble, R.; Jelinsky, P.; Grewing, M.; Kraemer, G.; Wulf-Mathies, C.

    1984-01-01

    The objective of the experiment reported here was to obtain additional information on the absolute intensity level and spatial variation of the diffuse ultraviolet background and thereby gain insight into the origin of this radiation. The experiment used three ultraviolet sensitive photometers placed in the focal plane of a 95-cm, f/2.8 normal incidence telescope flown on board an Aries sounding rocket. The measured intensities clearly refute the hypothesis of an isotropic background, the intensities of the high galactic latitude being definitely lower than the intensities seen at intermediate latitudes. Moreover, the count rates in all three channels along the slow scan exhibit local enhancements as well as an overall trend. In general, the spatial variations exhibited by the data correlate with the line of sight of neutral hydrogen column density as determined from 21-cm radio observations. This fact demonstrates that there is a galactic component to the diffuse ultraviolet radiation field.

  4. Deposit formation in hydrocarbon rocket fuels

    Science.gov (United States)

    Roback, R.; Szetela, E. J.; Spadaccini, L. J.

    1981-01-01

    An experimental program was conducted to study deposit formation in hydrocarbon fuels under flow conditions that exist in high-pressure, rocket engine cooling systems. A high pressure fuel coking test apparatus was designed and developed and was used to evaluate thermal decomposition (coking) limits and carbon deposition rates in heated copper tubes for two hydrocarbon rocket fuels, RP-1 and commercial-grade propane. Tests were also conducted using JP-7 and chemically-pure propane as being representative of more refined cuts of the baseline fuels. A parametric evaluation of fuel thermal stability was performed at pressures of 136 atm to 340 atm, bulk fuel velocities in the range 6 to 30 m/sec, and tube wall temperatures in the range 422 to 811 K. Results indicated that substantial deposit formation occurs with RP-1 fuel at wall temperatures between 600 and 800 K, with peak deposit formation occurring near 700 K. No improvements were obtained when deoxygenated JP-7 fuel was substituted for RP-1. The carbon deposition rates for the propane fuels were generally higher than those obtained for either of the kerosene fuels at any given wall temperature. There appeared to be little difference between commercial-grade and chemically-pure propane with regard to type and quantity of deposit. Results of tests conducted with RP-1 indicated that the rate of deposit formation increased slightly with pressure over the range 136 atm to 340 atm. Finally, lating the inside wall of the tubes with nickel was found to significantly reduce carbon deposition rates for RP-1 fuel.

  5. Ablative Rocket Deflector Testing and Computational Modeling

    Science.gov (United States)

    Allgood, Daniel C.; Lott, Jeffrey W.; Raines, Nickey

    2010-01-01

    A deflector risk mitigation program was recently conducted at the NASA Stennis Space Center. The primary objective was to develop a database that characterizes the behavior of industry-grade refractory materials subjected to rocket plume impingement conditions commonly experienced on static test stands. The program consisted of short and long duration engine tests where the supersonic exhaust flow from the engine impinged on an ablative panel. Quasi time-dependent erosion depths and patterns generated by the plume impingement were recorded for a variety of different ablative materials. The erosion behavior was found to be highly dependent on the material s composition and corresponding thermal properties. For example, in the case of the HP CAST 93Z ablative material, the erosion rate actually decreased under continued thermal heating conditions due to the formation of a low thermal conductivity "crystallization" layer. The "crystallization" layer produced near the surface of the material provided an effective insulation from the hot rocket exhaust plume. To gain further insight into the complex interaction of the plume with the ablative deflector, computational fluid dynamic modeling was performed in parallel to the ablative panel testing. The results from the current study demonstrated that locally high heating occurred due to shock reflections. These localized regions of shock-induced heat flux resulted in non-uniform erosion of the ablative panels. In turn, it was observed that the non-uniform erosion exacerbated the localized shock heating causing eventual plume separation and reversed flow for long duration tests under certain conditions. Overall, the flow simulations compared very well with the available experimental data obtained during this project.

  6. Computing Q-D Relationships for Storage of Rocket Fuels

    Science.gov (United States)

    Jester, Keith

    2005-01-01

    The Quantity Distance Measurement Tool is a GIS BASEP computer program that aids safety engineers by calculating quantity-distance (Q-D) relationships for vessels that contain explosive chemicals used in testing rocket engines. (Q-D relationships are standard relationships between specified quantities of specified explosive materials and minimum distances by which they must be separated from persons, objects, and other explosives to obtain specified types and degrees of protection.) The program uses customized geographic-information-system (GIS) software and calculates Q-D relationships in accordance with NASA's Safety Standard For Explosives, Propellants, and Pyrotechnics. Displays generated by the program enable the identification of hazards, showing the relationships of propellant-storage-vessel safety buffers to inhabited facilities and public roads. Current Q-D information is calculated and maintained in graphical form for all vessels that contain propellants or other chemicals, the explosiveness of which is expressed in TNT equivalents [amounts of trinitrotoluene (TNT) having equivalent explosive effects]. The program is useful in the acquisition, siting, construction, and/or modification of storage vessels and other facilities in the development of an improved test-facility safety program.

  7. Beginnings of rocket development in the czech lands (Czechoslovakia)

    Science.gov (United States)

    Plavec, Michal

    2011-11-01

    Although the first references are from the 15th Century when both Hussites and crusaders are said to have used rockets during the Hussite Wars (also known as the Bohemian Wars) there is no strong evidence that rockets were actually used at that time. It is worth noting that Konrad Kyeser, who described several rockets in his Bellifortis manuscript written 1402-1405, served as advisor to Bohemian King Wenceslas IV. Rockets were in fact used as fireworks from the 16th century in noble circles. Some of these were built by Vavřinec Křička z Bitý\\vsky, who also published a book on fireworks, in which he described how to build rockets for firework displays. Czech soldiers were also involved in the creation of a rocket regiment in the Austrian (Austro-Hungarian) army in the first half of the 19th century. The pioneering era of modern rocket development began in the Czech lands during the 1920s. The first rockets were succesfully launched by Ludvík Očenášek in 1930 with one of them possibly reaching an altitude of 2000 metres. Vladimír Mandl, lawyer and author of the first book on the subject of space law, patented his project for a stage rocket (vysokostoupající raketa) in 1932, but this project never came to fruition. There were several factories during the so-called Protectorate of Bohemia and Moravia in 1939-1945, when the Czech lands were occupied by Nazi Germany, where parts for German Mark A-4/V-2 rockets were produced, but none of the Czech technicians or constructors were able to build an entire rocket. The main goal of the Czech aircraft industry after WW2 was to revive the stagnant aircraft industry. There was no place to create a rocket industry. Concerns about a rocket industry appeared at the end of the 1950s. The Political Board of the Central Committee of the Czechoslovak Communist Party started to study the possibilities of creating a rocket industry after the first flight into space and particularly after US nuclear weapons were based in Italy

  8. Introduction to the Special Issue on Sounding Rockets and Instrumentation

    Science.gov (United States)

    Christe, Steven; Zeiger, Ben; Pfaff, Rob; Garcia, Michael

    2016-03-01

    Rocket technology, originally developed for military applications, has provided a low-cost observing platform to carry critical and rapid-response scientific investigations for over 70 years. Even with the development of launch vehicles that could put satellites into orbit, high altitude sounding rockets have remained relevant. In addition to science observations, sounding rockets provide a unique technology test platform and a valuable training ground for scientists and engineers. Most importantly, sounding rockets remain the only way to explore the tenuous regions of the Earth’s atmosphere (the upper stratosphere, mesosphere, and lower ionosphere/thermosphere) above balloon altitudes (˜40km) and below satellite orbits (˜160km). They can lift remote sensing telescope payloads with masses up to 400kg to altitudes of 350km providing observing times of up to 6min above the blocking influence of Earth’s atmosphere. Though a number of sounding rocket research programs exist around the world, this article focuses on the NASA Sounding Rocket Program, and particularly on the astrophysical and solar sounding rocket payloads.

  9. Water rocket - Electrolysis propulsion and fuel cell power

    Energy Technology Data Exchange (ETDEWEB)

    Carter, P H; Dittman, M D; Kare, J T; Militsky, F; Myers, B; Weisberg, A H

    1999-07-24

    Water Rocket is the collective name for an integrated set of technologies that offer new options for spacecraft propulsion, power, energy storage, and structure. Low pressure water stored on the spacecraft is electrolyzed to generate, separate, and pressurize gaseous hydrogen and oxygen. These gases, stored in lightweight pressure tanks, can be burned to generate thrust or recombined to produce electric power. As a rocket propulsion system, Water Rocket provides the highest feasible chemical specific impulse (-400 seconds). Even higher specific impulse propulsion can be achieved by combining Water Rocket with other advanced propulsion technologies, such as arcjet or electric thrusters. With innovative pressure tank technology, Water Rocket's specific energy [Wh/kg] can exceed that of the best foreseeable batteries by an order of magnitude, and the tanks can often serve as vehicle structural elements. For pulsed power applications, Water Rocket propellants can be used to drive very high power density generators, such as MHD devices or detonation-driven pulse generators. A space vehicle using Water Rocket propulsion can be totally inert and non-hazardous during assembly and launch. These features are particularly important for the timely development and flight qualification of new classes of spacecraft, such as microsats, nanosats, and refuelable spacecraft.

  10. Investigations of Rocket Engine Combustion Emissions During ACCENT

    Science.gov (United States)

    Ross, M. N.; Friedl, R. R.

    2001-12-01

    The composition of rocket combustion emissions and the atmospheric processes that determine their stratospheric impacts are poorly understood. While present day rocket emissions do not significantly affect stratospheric chemistry, the potential for vigorous growth of the space transportation industry in coming decades suggests that rocket emissions and their stratospheric impacts should be better understood. A variety of in-situ measurements and modeling results were obtained during the Atmospheric Chemistry of Combustion Emissions Near the Tropopause (ACCENT) effort that will be used to evaluate the role of rocket exhaust in perturbing ozone chemistry in plume wakes and in the global stratosphere. We present a review of the ACCENT rocket emissions science objectives, summarize data obtained during the WB-57F plume wake sorties, and briefly discuss how the data will help resolve several outstanding questions regarding the impact of rocket emissions on the stratosphere. These include measurement of the emission indices for several important rocket engine combustion products and validation of plume wake chemistry models.

  11. Numerical and experimental capabilities for studying rocket plume-regolith interactions

    Science.gov (United States)

    White, C.; Scanlon, T. J.; Merrifield, J. A.; Kontis, K.; Langener, T.; Alves, J.

    2016-11-01

    Soft landings on extra-terrestrial airless bodies will be required for future sample return missions, such as the Phobos Sample Return (PhSR). PhSR is a candidate mission of ESA's Mars Robotic Exploration Preparation (MREP-2) Programme. Its main objective is to acquire and return a sample from the Martian moon Phobos, after a scientific characterisation phase of the moon and of the landing site. If a rocket is used to slow down the spacecraft to a vertical descent velocity that it will be able to free-fall from, care has to be taken to ensure that the rocket exhaust does not contaminate the surface regolith that is to be collected, and that the rocket does not cause unacceptable levels of erosion to the surface, which could jeopardise the mission. In addition to the work being done in the scope of PhSR, the European Space Agency is funding an experimental facility for investigating these nozzle expansion problems; the current progress of this is described. To support this work, an uncoupled hybrid computational fluid dynamics-direct simulation Monte Carlo method is developed and used to simulate the exhaust of a mono-propellant rocket above the surface of an airless body. The pressure, shear stress, and heat flux at the surface are compared to an analytical free-molecul solution to determine the altitude above which the free-molecular solution is suffcient for predicting these properties. The pressures match well as low as 15 m above the surface, but the heat flux and shear stress are not in agreement until an altitude of 40 m. A new adsorption/desorption boundary condition for the direct simulation Monte Carlo code has also been developed for future use in in-depth contamination studies.

  12. Rocket nozzle thermal shock tests in an arc heater facility

    Science.gov (United States)

    Painter, James H.; Williamson, Ronald A.

    1986-01-01

    A rocket motor nozzle thermal structural test technique that utilizes arc heated nitrogen to simulate a motor burn was developed. The technique was used to test four heavily instrumented full-scale Star 48 rocket motor 2D carbon/carbon segments at conditions simulating the predicted thermal-structural environment. All four nozzles survived the tests without catastrophic or other structural failures. The test technique demonstrated promise as a low cost, controllable alternative to rocket motor firing. The technique includes the capability of rapid termination in the event of failure, allowing post-test analysis.

  13. Optimization of Construction of the rocket-assisted projectile

    Directory of Open Access Journals (Sweden)

    Arkhipov Vladimir

    2017-01-01

    Full Text Available New scheme of the rocket motor of rocket-assisted projectile providing the increase in distance of flight due to controlled and optimal delay time of ignition of the solid-propellant charge of the SRM and increase in reliability of initiation of the SRM by means of the autonomous system of ignition excluding the influence of high pressure gases of the propellant charge in the gun barrel has been considered. Results of the analysis of effectiveness of using of the ignition delay device on motion characteristics of the rocket-assisted projectile has been presented.

  14. Flow separation in rocket nozzles under high altitude condition

    Science.gov (United States)

    Stark, R.; Génin, C.

    2017-01-01

    The knowledge of flow separation in rocket nozzles is crucial for rocket engine design and optimum performance. Typically, flow separation is studied under sea-level conditions. However, this disregards the change of the ambient density during ascent of a launcher. The ambient flow properties are an important factor concerning the design of altitude-adaptive rocket nozzles like the dual bell nozzle. For this reason an experimental study was carried out to study the influence of the ambient density on flow separation within conventional nozzles.

  15. ACTIVE MODEL ROCKET STABILIZATION VIA COLD GAS THRUSTERS

    OpenAIRE

    Malyuta, Danylo; Collaud, Xavier; Martins Gaspar, Mikael; Rouaze, Gautier Marie Pierre; Pictet, Raimondo; Ivanov, Anton; Mullin, Nickolay

    2015-01-01

    This paper describes the development and testing of a reaction control system (RCS) for a model rocket named FALCO-4. The rocket uses cold gas jets to keep itself perfectly vertical at low speeds. We first describe the mechanical layout of FALCO-4 and the characteristics of the cold gas propulsion system. We then propose a dynamical model of the rocket and a control scheme based on decoupled PID regulators for roll, pitch and yaw. The control scheme is then evaluated based on MATLAB simulatio...

  16. Characterization of rocket propellant combustion products: Description of sampling and analysis methods for rocket exhaust characterization studies

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, R.A.

    1990-06-07

    A systematic approach has been developed and experimentally validated for the sampling and chemical characterization of the rocket motor exhaust generated from the firing of scaled down test motors at the US Army's Signature Characterization Facility (ASCF) at Redstone Arsenal in Huntsville, Alabama. The overall strategy was to sample and analyze major exhaust constituents in near real time, while performing off-site analyses of samples collected for the determination of trace constituents of the particulate and vapor phases. Initial interference studies were performed using atmospheric pressure burns of 1 g quantities of propellants in small chambers at Oak Ridge National Laboratory. Carbon monoxide and carbon dioxide were determined using non-dispersive infrared instrumentation. Hydrogen cyanide, hydrogen chloride, and ammonia determinations were made using ion selective electrode technology. Oxides of nitrogen were determined using chemiluminescence instrumentation. Airborne particulate mass concentration was determined using infrared forward scattering measurements and a tapered element oscillating microbalance, as well as conventional gravimetry. Particulate phase metals were determined by collection on Teflon membrane filters, followed by inductively coupled plasma and atomic absorption analysis. Particulate phase polynuclear aromatic hydrocarbons (PAH) and nitro-PAH were collected using high volume sampling on a two stage filter. Target species were extracted, and quantified by gas chromatography/mass spectrometry (GC/MS). Vapor phase species were collected on multi-sorbent resin traps, and subjected to thermal desorption GC/MS for analysis. 11 refs., 1 fig., 1 tab.

  17. Improving of Hybrid Rocket Engine on the Basis of Optimizing Design Fuel Grain

    Science.gov (United States)

    Oriekov, K. M.; Ushkin, M. P.

    2015-09-01

    This article examines the processes intrachamber in hybrid rocket engine (HRE) and the comparative assessment of the use of solid rocket motors (SRM) and HRE for meteorological rockets with a mass of payload of the 364 kg. Results of the research showed the possibility of a significant increase in the ballistic effectiveness of meteorological rocket.

  18. On the history of the development of solid-propellant rockets in the Soviet Union

    Science.gov (United States)

    Pobedonostsev, Y. A.

    1977-01-01

    Pre-World War II Soviet solid-propellant rocket technology is reviewed. Research and development regarding solid composite preparations of pyroxyline TNT powder is described, as well as early work on rocket loading calculations, problems of flight stability, and aircraft rocket launching and ground rocket launching capabilities.

  19. Water Impact Prediction Tool for Recoverable Rockets

    Science.gov (United States)

    Rooker, William; Glaese, John; Clayton, Joe

    2011-01-01

    Reusing components from a rocket launch can be cost saving. NASA's space shuttle system has reusable components that return to the Earth and impact the ocean. A primary example is the Space Shuttle Solid Rocket Booster (SRB) that descends on parachutes to the Earth after separation and impacts the ocean. Water impact generates significant structural loads that can damage the booster, so it is important to study this event in detail in the design of the recovery system. Some recent examples of damage due to water impact include the Ares I-X First Stage deformation as seen in Figure 1 and the loss of the SpaceX Falcon 9 First Stage.To ensure that a component can be recovered or that the design of the recovery system is adequate, an adequate set of structural loads is necessary for use in failure assessments. However, this task is difficult since there are many conditions that affect how a component impacts the water and the resulting structural loading that a component sees. These conditions include the angle of impact with respect to the water, the horizontal and vertical velocities, the rotation rate, the wave height and speed, and many others. There have been attempts to simulate water impact. One approach is to analyze water impact using explicit finite element techniques such as those employed by the LS-Dyna tool [1]. Though very detailed, this approach is time consuming and would not be suitable for running Monte Carlo or optimization analyses. The purpose of this paper is to describe a multi-body simulation tool that runs quickly and that captures the environments a component might see. The simulation incorporates the air and water interaction with the component, the component dynamics (i.e. modes and mode shapes), any applicable parachutes and lines, the interaction of winds and gusts, and the wave height and speed. It is capable of quickly conducting Monte Carlo studies to better capture the environments and genetic algorithm optimizations to reproduce a

  20. Combined ground-based optical support for the aurora (DELTA) sounding rocket campaign

    Science.gov (United States)

    Griffin, Eoghan; Kosch, Mike; Aruliah, Anasuya; Kavanagh, Andrew; McWhirter, Ian; Senior, Andrew; Ford, Elaina; Davis, Chris; Abe, Takumi; Kurihara, Junichi; Kauristie, Kirsti; Ogawa, Yasunobu

    2006-09-01

    The Japan Aerospace Exploration Agency (JAXA) DELTA rocket experiment, successfully launched from Andøya at 0033 UT on December 13, 2004, supported by ground based optical instruments, primarily 2 Fabry- Perot Interferometers (FPIs) located at Skibotn, Norway (69.3°N, 20.4°E) and the KEOPS Site, Esrange, Kiruna, Sweden (67.8°N, 20.4°E). Both these instruments sampled the 557.7 nm lower thermosphere atomic oxygen emission and provided neutral temperatures and line-of-sight wind velocities, with deduced vector wind patterns over each site. All sky cameras allow contextual auroral information to be acquired. The proximity of the sites provided overlapping fields of view, adjacent to the trajectory of the DELTA rocket. This allowed independent verification of the absolute temperatures in the relatively quiet conditions early in the night, especially important given the context provided by co-located EISCAT ion temperature measurements which allow investigation of the likely emission altitude of the passive FPI measurements. The results demonstrate that this altitude changes from 120 km pre-midnight to 115 km post-midnight. Within this large scale context the results from the FPIs also demonstrate smaller scale structure in neutral temperatures, winds and intensities consistent with localised heating. These results present a challenge to the representation of thermospheric variability for the existing models of the region.

  1. Tactical Grade MEMS IMUs for Spin-Stabilized Rockets Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a tactical grade MEMS IMU for spin-stabilized rockets for metric tracking and autonomous systems. The enabling instrument is a gyroscope designed for very...

  2. Safety Analysis of Liquid Rocket Engine Using Bayesian Networks

    Institute of Scientific and Technical Information of China (English)

    WANG Hua-wei; YAN Zhi-qiang

    2007-01-01

    Safety analysis for liquid rocket engine has a great meaning for shortening development cycle, saving development expenditure and reducing development risk. The relationship between the structure and component of liquid rocket engine is much more complex, furthermore test data are absent in development phase. Thereby, the uncertainties exist in safety analysis for liquid rocket engine. A safety analysis model integrated with FMEA(failure mode and effect analysis)based on Bayesian networks (BN) is brought forward for liquid rocket engine, which can combine qualitative analysis with quantitative decision. The method has the advantages of fusing multi-information, saving sample amount and having high veracity. An example shows that the method is efficient.

  3. Economical Mars Exploration Supported by a Nuclear Thermal Rocket

    Science.gov (United States)

    Howe, S. D.; O'Brien, R. C.

    2012-06-01

    A nuclear thermal rocket (NTR) developed for human Mars missions could act as a "mother ship" and carry multiple unmanned platforms to Mars for independent deployment. Use of the NTR could increase the science per dollar for each Earth launch.

  4. Propellant Flow Actuated Piezoelectric Rocket Engine Igniter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Spark ignition of a bi-propellant rocket engine is a classic, proven, and generally reliable process. However, timing can be critical, and the control logic,...

  5. Distributed Rocket Engine Testing Health Monitoring System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Leveraging the Phase I achievements of the Distributed Rocket Engine Testing Health Monitoring System (DiRETHMS) including its software toolsets and system building...

  6. SpaceX rocket fuel plan under scrutiny

    Science.gov (United States)

    Gwynne, Peter

    2016-12-01

    NASA's International Space Station advisory committee has raised concerns about SpaceX's plans to fuel rockets that are used to ferry astronauts to the International Space Station (ISS) while the crew is onboard.

  7. Distributed Rocket Engine Testing Health Monitoring System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The on-ground and Distributed Rocket Engine Testing Health Monitoring System (DiRETHMS) provides a system architecture and software tools for performing diagnostics...

  8. Taming Liquid Hydrogen: The Centaur Upper Stage Rocket

    Science.gov (United States)

    2004-01-01

    The Centaur is one of the most powerful rockets in the world. As an upper-stage rocket for the Atlas and Titan boosters it has been a reliable workhorse for NASA for over forty years and has played an essential role in many of NASA's adventures into space. In this CD-ROM you will be able to explore the Centaur's history in various rooms to this virtual museum. Visit the "Movie Theater" to enjoy several video documentaries on the Centaur. Enter the "Interview Booth" to hear and read interviews with scientists and engineers closely responsible for building and operating the rocket. Go to the "Photo Gallery" to look at numerous photos of the rocket throughout its history. Wander into the "Centaur Library" to read various primary documents of the Centaur program. Finally, stop by the "Observation Deck" to watch a virtual Centaur in flight.

  9. Mars McLOX Rocket Propulsion System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Methane and Carbon Monoxide/LOX rocket (MCLOX) is a technology for accomplishing ascent from Mars. Current Mars in-situ propellant production (ISPP) technologies...

  10. Rocket Fuel Synthesis by Fisher-Tropsch Process Project

    Data.gov (United States)

    National Aeronautics and Space Administration — While In-Situ Resource Utilization (ISRU) studies for Mars return have emphasized methane fuel, only modest work has been done to develop the methane-powered rocket...

  11. Gaseous Helium Reclamation at Rocket Test Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — GHe reclamation is critical in reducing operating costs at rocket engine test facilities. Increases in cost and shortages of helium will dramatically impact testing...

  12. Simulation and experimental research on line throwing rocket with flight

    Institute of Scientific and Technical Information of China (English)

    Wen-bin GU; Ming LU; Jian-qing LIU; Qin-xing DONG; Zhen-xiong WANG; Jiang-hai CHEN

    2014-01-01

    The finite segment method is used to model the line throwing rocket system. A dynamic model of line throwing rocket with flight motion based on Kane’s method is presented by the kinematics description of the system and the consideration of the forces acting on the system. The experiment designed according to the parameters of the dynamic model is made. The simulation and experiment results, such as range, velocity and flight time, are compared and analyzed. The simulation results are basically agreed with the test data, which shows that the flight motion of the line throwing rocket can be predicted by the dynamic model. A theoretical model and guide for the further research on the disturbance of rope and the guidance, flight control of line throwing rocket are provided by the dynamic modeling.

  13. The development of space solid rocket motors in China

    Science.gov (United States)

    Jianding, Huang; Dingyou, Ye

    1997-01-01

    China has undertaken to research and develop composite solid propellant rocket motors since 1958. At the request of the development of space technology, composite solid propellant rocket motor has developed from small to large, step by step. For the past thirty eight years, much progress has made, many technical obstacles, such as motor design, case materials and their processing technology, propellant formulations and manufacture, nozzles and thrust vector control, safe ignition, environment tests, nondestructive inspection and quality assurance, static firing test and measurement etc. have been solved. A serial of solid rocket motors have been offered for China's satellites launch. The systems of research, design, test and manufacture of solid rocket motors have been formed.

  14. Scale-Up of GRCop: From Laboratory to Rocket Engines

    Science.gov (United States)

    Ellis, David L.

    2016-01-01

    GRCop is a high temperature, high thermal conductivity copper-based series of alloys designed primarily for use in regeneratively cooled rocket engine liners. It began with laboratory-level production of a few grams of ribbon produced by chill block melt spinning and has grown to commercial-scale production of large-scale rocket engine liners. Along the way, a variety of methods of consolidating and working the alloy were examined, a database of properties was developed and a variety of commercial and government applications were considered. This talk will briefly address the basic material properties used for selection of compositions to scale up, the methods used to go from simple ribbon to rocket engines, the need to develop a suitable database, and the issues related to getting the alloy into a rocket engine or other application.

  15. Dynamical Model of Rocket Propellant Loading with Liquid Hydrogen

    Data.gov (United States)

    National Aeronautics and Space Administration — A dynamical model describing the multi-stage process of rocket propellant loading has been developed. It accounts for both the nominal and faulty regimes of...

  16. Energy-Based Acoustic Measurement System for Rocket Noise Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Accurate estimates of the vibroacoustic loading placed on space vehicles and payloads during launch require knowledge of the rocket noise source properties. Given...

  17. Oxidizer heat exchangers for rocket engine operation in idle modes

    Science.gov (United States)

    Kanic, P. G.; Kmiec, T. D.

    1987-01-01

    The heat exchanger concept is discussed together with its role in rocket engine operation in idle modes. Two heat exchanger designs (low and high heat transfer) utilizing different approaches to achieve stable oxygen vaporization are presented as well as their performance test results. It is concluded that compact and lightweight heat exchangers can be used in a stable manner under the 'idle' operating conditions expected with the RL10 rocket engine.

  18. Rocketdyne/Westinghouse nuclear thermal rocket engine modeling

    Science.gov (United States)

    Glass, James F.

    1993-01-01

    The topics are presented in viewgraph form and include the following: systems approach needed for nuclear thermal rocket (NTR) design optimization; generic NTR engine power balance codes; rocketdyne nuclear thermal system code; software capabilities; steady state model; NTR engine optimizer code-logic; reactor power calculation logic; sample multi-component configuration; NTR design code output; generic NTR code at Rocketdyne; Rocketdyne NTR model; and nuclear thermal rocket modeling directions.

  19. Numerical and Experimental Investigation of Hybrid Rocket Motors Transient Behavior

    OpenAIRE

    Barato, Francesco

    2013-01-01

    As the space business is shifting from pure performances to affordability a renewed interest is growing about hybrid rocket propulsion. Hybrid rocket motors are attractive for their inherent advantages like simplicity, reliability, safety and reduced costs. Moreover hybrid motors are easy to throttle and thus they are ideal candidate when soft-landing or energy management capabilities are required. This thesis is mainly involved with a theoretical/numerical study of hybrid transie...

  20. Laser Ignition Technology for Bi-Propellant Rocket Engine Applications

    Science.gov (United States)

    Thomas, Matt; Bossard, John; Early, Jim; Trinh, Huu; Dennis, Jay; Turner, James (Technical Monitor)

    2001-01-01

    This viewgraph presentation gives an overview of laser ignition technology for bipropellant rocket engines applications. The objectives of this project include: (1) the selection test chambers and flows; (2) definition of the laser ignition setup; (3) pulse format optimization; (4) fiber optic coupled laser ignition system analysis; and (5) chamber integration issues definition. The testing concludes that rocket combustion chamber laser ignition is imminent. Support technologies (multiplexing, window durability/cleaning, and fiber optic durability) are feasible.

  1. Magnetohydrodynamic Augmentation of Pulse Detonation Rocket Engines (Preprint)

    Science.gov (United States)

    2010-09-28

    Detonation Rocket-Induced MHD Ejector (PDRIME) concept, energy could be extracted from the high speed portion of the system, e.g., through an MHD...but with some challenges associated with achieving these gains, suggesting further analysis and optimization are required. 15. SUBJECT TERMS 16...mentation, such as in the Pulse Detonation Rocket-Induced MHD Ejector (PDRIME) concept, energy could be extracted from the high speed por- tion of the system

  2. Solid Rocket Motor Design Using Hybrid Optimization

    Directory of Open Access Journals (Sweden)

    Kevin Albarado

    2012-01-01

    Full Text Available A particle swarm/pattern search hybrid optimizer was used to drive a solid rocket motor modeling code to an optimal solution. The solid motor code models tapered motor geometries using analytical burn back methods by slicing the grain into thin sections along the axial direction. Grains with circular perforated stars, wagon wheels, and dog bones can be considered and multiple tapered sections can be constructed. The hybrid approach to optimization is capable of exploring large areas of the solution space through particle swarming, but is also able to climb “hills” of optimality through gradient based pattern searching. A preliminary method for designing tapered internal geometry as well as tapered outer mold-line geometry is presented. A total of four optimization cases were performed. The first two case studies examines designing motors to match a given regressive-progressive-regressive burn profile. The third case study studies designing a neutrally burning right circular perforated grain (utilizing inner and external geometry tapering. The final case study studies designing a linearly regressive burning profile for right circular perforated (tapered grains.

  3. Thrust Vector Control for Nuclear Thermal Rockets

    Science.gov (United States)

    Ensworth, Clinton B. F.

    2013-01-01

    Future space missions may use Nuclear Thermal Rocket (NTR) stages for human and cargo missions to Mars and other destinations. The vehicles are likely to require engine thrust vector control (TVC) to maintain desired flight trajectories. This paper explores requirements and concepts for TVC systems for representative NTR missions. Requirements for TVC systems were derived using 6 degree-of-freedom models of NTR vehicles. Various flight scenarios were evaluated to determine vehicle attitude control needs and to determine the applicability of TVC. Outputs from the models yielded key characteristics including engine gimbal angles, gimbal rates and gimbal actuator power. Additional factors such as engine thrust variability and engine thrust alignment errors were examined for impacts to gimbal requirements. Various technologies are surveyed for TVC systems for the NTR applications. A key factor in technology selection is the unique radiation environment present in NTR stages. Other considerations including mission duration and thermal environments influence the selection of optimal TVC technologies. Candidate technologies are compared to see which technologies, or combinations of technologies best fit the requirements for selected NTR missions. Representative TVC systems are proposed and key properties such as mass and power requirements are defined. The outputs from this effort can be used to refine NTR system sizing models, providing higher fidelity definition for TVC systems for future studies.

  4. Nuclear thermal rockets using indigenous extraterrestrial propellants

    Science.gov (United States)

    Zubrin, Robert M.

    1990-01-01

    A preliminary examination of a concept for a Mars and outer solar system exploratory vehicle is presented. Propulsion is provided by utilizing a nuclear thermal reactor to heat a propellant volatile indigenous to the destination world to form a high thrust rocket exhaust. Candidate propellants, whose performance, materials compatibility, and ease of acquisition are examined and include carbon dioxide, water, methane, nitrogen, carbon monoxide, and argon. Ballistics and winged supersonic configurations are discussed. It is shown that the use of this method of propulsion potentially offers high payoff to a manned Mars mission. This is accomplished by sharply reducing the initial mission mass required in low earth orbit, and by providing Mars explorers with greatly enhanced mobility in traveling about the planet through the use of a vehicle that can refuel itself each time it lands. Thus, the nuclear landing craft is utilized in combination with a hydrogen-fueled nuclear-thermal interplanetary launch. By utilizing such a system in the outer solar system, a low level aerial reconnaissance of Titan combined with a multiple sample return from nearly every satellite of Saturn can be accomplished in a single launch of a Titan 4 or the Space Transportation System (STS). Similarly a multiple sample return from Callisto, Ganymede, and Europa can also be accomplished in one launch of a Titan 4 or the STS.

  5. Analysis of Regen Cooling in Rocket Combustors

    Science.gov (United States)

    Harper, Brent (Technical Monitor); Merkle, C. L.; Li, D.; Sankaran, V.

    2004-01-01

    The use of detailed CFD modeling for the description of cooling in rocket chambers is discussed. The overall analysis includes a complete three-dimensional analysis of the flow in the regenerative cooling passages, conjugate heat transfer in the combustor walls, and the effects of film cooling on the inside chamber. The results in the present paper omit the effects of film cooling and include only regen cooling and the companion conjugate heat transfer. The hot combustion gases are replaced by a constant temperature wall boundary condition. Load balancing for parallel cluster computations is ensured by using single-block unstructured grids for both fluids and solids, and by using a 'multiple physical zones' to account for differences in the number of equations. Validation of the method is achieved by comparing simple two-dimensional solutions with analytical results. Representative results for cooling passages are presents showing the effects of heat conduction in the copper walls with tube aspect ratios of 1.5:l.

  6. MHD thrust vectoring of a rocket engine

    Science.gov (United States)

    Labaune, Julien; Packan, Denis; Tholin, Fabien; Chemartin, Laurent; Stillace, Thierry; Masson, Frederic

    2016-09-01

    In this work, the possibility to use MagnetoHydroDynamics (MHD) to vectorize the thrust of a solid propellant rocket engine exhaust is investigated. Using a magnetic field for vectoring offers a mass gain and a reusability advantage compared to standard gimbaled, elastomer-joint systems. Analytical and numerical models were used to evaluate the flow deviation with a 1 Tesla magnetic field inside the nozzle. The fluid flow in the resistive MHD approximation is calculated using the KRONOS code from ONERA, coupling the hypersonic CFD platform CEDRE and the electrical code SATURNE from EDF. A critical parameter of these simulations is the electrical conductivity, which was evaluated using a set of equilibrium calculations with 25 species. Two models were used: local thermodynamic equilibrium and frozen flow. In both cases, chlorine captures a large fraction of free electrons, limiting the electrical conductivity to a value inadequate for thrust vectoring applications. However, when using chlorine-free propergols with 1% in mass of alkali, an MHD thrust vectoring of several degrees was obtained.

  7. Measurements of reactive gaseous rocket injector admittances

    Science.gov (United States)

    Janardan, B. A.; Daniel, B. R.; Bell, W. A.; Zinn, B. T.

    1979-01-01

    The paper describes the results of an experimental study of the quantitative determination of the capabilities of the combustion processes associated with coaxial gaseous propellant rocket injectors to drive combustor pressure oscillations. The data, obtained by employing the modified impedance tube technique with compressed air as the oxidizer and acetylene gas as the fuel, describe the frequency dependence of the admittance of the combined injector-combustion process. The measured data are compared with the predictions of the Feiler and Heidmann analytical model utilizing different values for the characteristic combustion time tau sub b. The values of tau sub b which result in a best fit between the measured and predicted data are indicated for different equivalence ratios. It is shown that for the coaxial injector investigated in this study the tau sub b varies between 0.7 and 1.2 msec for equivalence ratios in the range of 0.57 to 1.31. In addition, the experimental data indicate that the tested injector system could drive combustion instabilities over a frequency range that is in qualitative agreement with the predictions of the Feiler and Heidmann model.

  8. Injector for liquid fueled rocket engine

    Science.gov (United States)

    Cornelius, Charles S. (Inventor); Myers, W. Neill (Inventor); Shadoan, Michael David (Inventor); Sparks, David L. (Inventor)

    2000-01-01

    An injector for liquid fueled rocket engines wherein a generally flat core having a frustoconical dome attached to one side of the core to serve as a manifold for a first liquid, with the core having a generally circular configuration having an axis. The other side of the core has a plurality of concentric annular first slots and a plurality of annular concentric second slots alternating with the first slots, the second slots having a greater depth than said first slots. A bore extends through the core for inletting a second liquid into said core, the bore intersecting the second slots to feed the second liquid into the second slots. The core also has a plurality of first passageways leading from the manifold to the first annular slots for feeding the first liquid into said first slots. A faceplate brazed to said other side of the core is provided with apertures extending from the first and second slots through said face plate, these apertures being positioned to direct fuel and liquid oxygen into contact with each other in the combustion chamber. The first liquid may be liquid oxygen and the second liquid may be kerosene or liquid hydrogen.

  9. Ammonium nitrate: a promising rocket propellant oxidizer

    Science.gov (United States)

    Oommen; Jain

    1999-06-30

    Ammonium nitrate (AN) is extensively used in the area of fertilizers and explosives. It is present as the major component in most industrial explosives. Its use as an oxidizer in the area of propellants, however, is not as extensive as in explosive compositions or gas generators. With the growing demand for environmental friendly chlorine free propellants, many attempts have been made of late to investigate oxidizers producing innocuous combustion products. AN, unlike the widely used ammonium perchlorate, produces completely ecofriendly smokeless products. Besides, it is one of the cheapest and easily available compounds. However, its use in large rocket motors is restricted due to some of its adverse characteristics like hygroscopicity, near room temperature phase transformation involving a volume change, and low burning rate (BR) and energetics. The review is an attempt to consolidate the information available on the various issues pertaining to its use as a solid propellant oxidizer. Detailed discussions on the aspects relating to phase modifications, decomposition chemistry, and BR and energetics of AN-based propellants, are presented. To make the review more comprehensive brief descriptions of the history, manufacture, safety, physical and chemical properties and various other applications of the salt are also included. Copyright 1999 Elsevier Science B.V.

  10. Hypothetical Dark Matter/axion Rockets:. Dark Matter in Terms of Space Physics Propulsion

    Science.gov (United States)

    Beckwith, A.

    2010-12-01

    Current proposed photon rocket designs include the Nuclear Photonic Rocket and the Antimatter Photonic Rocket (proposed by Eugen Sanger in the 1950s, as reported by Ref. 1). This paper examines the feasibility of improving the thrust of photon-driven ramjet propulsion by using DM rocket propulsion. The open question is: would a heavy WIMP, if converted to photons, upgrade the power (thrust) of a photon rocket drive, to make interstellar travel a feasible proposition?

  11. Turbopump Design and Analysis Approach for Nuclear Thermal Rockets

    Science.gov (United States)

    Chen, Shu-cheng S.; Veres, Joseph P.; Fittje, James E.

    2006-01-01

    A rocket propulsion system, whether it is a chemical rocket or a nuclear thermal rocket, is fairly complex in detail but rather simple in principle. Among all the interacting parts, three components stand out: they are pumps and turbines (turbopumps), and the thrust chamber. To obtain an understanding of the overall rocket propulsion system characteristics, one starts from analyzing the interactions among these three components. It is therefore of utmost importance to be able to satisfactorily characterize the turbopump, level by level, at all phases of a vehicle design cycle. Here at NASA Glenn Research Center, as the starting phase of a rocket engine design, specifically a Nuclear Thermal Rocket Engine design, we adopted the approach of using a high level system cycle analysis code (NESS) to obtain an initial analysis of the operational characteristics of a turbopump required in the propulsion system. A set of turbopump design codes (PumpDes and TurbDes) were then executed to obtain sizing and performance characteristics of the turbopump that were consistent with the mission requirements. A set of turbopump analyses codes (PUMPA and TURBA) were applied to obtain the full performance map for each of the turbopump components; a two dimensional layout of the turbopump based on these mean line analyses was also generated. Adequacy of the turbopump conceptual design will later be determined by further analyses and evaluation. In this paper, descriptions and discussions of the aforementioned approach are provided and future outlooks are discussed.

  12. Turbopump Design and Analysis Approach for Nuclear Thermal Rockets

    Science.gov (United States)

    Chen, Shu-Cheng S.; Veres, Joseph P.; Fittje, James E.

    2006-01-01

    A rocket propulsion system, whether it is a chemical rocket or a nuclear thermal rocket, is fairly complex in detail but rather simple in principle. Among all the interacting parts, three components stand out: they are pumps & turbines (turbopumps), and the thrust chamber. To obtain an understanding of the overall rocket propulsion system characteristics, one starts from analyzing the interactions among these three components. It is therefore of utmost importance to be able to satisfactorily characterize the turbopump, level by level, at all phases of a vehicle design cycle. Here at the NASA Glenn Research Center, as the starting phase of a rocket engine design, specifically a Nuclear Thermal Rocket Engine design, we adopted the approach of using a high level system cycle analysis code (NESS) to obtain an initial analysis of the operational characteristics of a turbopump required in the propulsion system. A set of turbopump design codes (PumpDes and TurbDes) were then executed to obtain sizing and performance parameters of the turbopump that were consistent with the mission requirements. A set of turbopump analyses codes (PUMPA and TURBA) were applied to obtain the full performance map for each of the turbopump components; a two dimensional layout of the turbopump based on these mean line analyses was also generated. Adequacy of the turbopump conceptual design will later be determined by further analyses and evaluation. In this paper, descriptions and discussions of the aforementioned approach are provided and future outlooks are discussed.

  13. The Alfred Nobel rocket camera. An early aerial photography attempt

    Science.gov (United States)

    Ingemar Skoog, A.

    2010-02-01

    Alfred Nobel (1833-1896), mainly known for his invention of dynamite and the creation of the Nobel Prices, was an engineer and inventor active in many fields of science and engineering, e.g. chemistry, medicine, mechanics, metallurgy, optics, armoury and rocketry. Amongst his inventions in rocketry was the smokeless solid propellant ballistite (i.e. cordite) patented for the first time in 1887. As a very wealthy person he actively supported many Swedish inventors in their work. One of them was W.T. Unge, who was devoted to the development of rockets and their applications. Nobel and Unge had several rocket patents together and also jointly worked on various rocket applications. In mid-1896 Nobel applied for patents in England and France for "An Improved Mode of Obtaining Photographic Maps and Earth or Ground Measurements" using a photographic camera carried by a "…balloon, rocket or missile…". During the remaining of 1896 the mechanical design of the camera mechanism was pursued and cameras manufactured. In April 1897 (after the death of Alfred Nobel) the first aerial photos were taken by these cameras. These photos might be the first documented aerial photos taken by a rocket borne camera. Cameras and photos from 1897 have been preserved. Nobel did not only develop the rocket borne camera but also proposed methods on how to use the photographs taken for ground measurements and preparing maps.

  14. Applying a toolkit for dissemination and analysis of near real-time data through the World Wide Web: integration of the Antelope Real Time System, ROADNet, and PHP

    Science.gov (United States)

    Newman, R. L.; Lindquist, K. G.; Hansen, T. S.; Vernon, F. L.; Eakins, J.; Foley, S.; Orcutt, J.

    2005-12-01

    The ROADNet project has enabled the acquisition and storage of diverse data streams through seamless integration of the Antelope Real Time System (ARTS) with (for example) ecological, seismological and geodetic instrumentation. The robust system architecture allows researchers to simply network data loggers with relational databases; however, the ability to disseminate these data to policy makers, scientists and the general public has (until recently) been provided on an 'as needed' basis. The recent development of a Datascope interface to the popular open source scripting language PHP has provided an avenue for presenting near real time data (such as integers, images and movies) from within the ARTS framework easily on the World Wide Web. The interface also indirectly provided the means to transform data types into various formats using the extensive function libraries that accompany a PHP installation (such as image creation and manipulation, data encryption for sensitive information, and XML creation for structured document interchange through the World Wide Web). Using a combination of Datascope and PHP library functions, an extensible tool-kit is being developed to allow data managers to easily present their products on the World Wide Web. The tool-kit has been modeled after the pre-existing ARTS architecture to simplify the installation, development and ease-of-use for both the seasoned researcher and the casual user. The methodology and results of building the applications that comprise the tool-kit are the focus of this presentation, including procedural vs. object oriented design, incorporation of the tool-kit into the existing contributed software libraries, and case-studies of researchers who are employing the tools to present their data. http://anf.ucsd.edu

  15. Using the satellite-derived normalized difference vegetation index (NDVI) to explain ranging patterns in a lek-breeding antelope: the importance of scale.

    Science.gov (United States)

    Bro-Jørgensen, Jakob; Brown, Molly E; Pettorelli, Nathalie

    2008-11-01

    Lek-breeding species are characterized by a negative association between territorial resource availability and male mating success; however, the impact of resources on the overall distribution patterns of the two sexes in lek systems is not clear. The normalized difference vegetation index (NDVI) has recently emerged as a powerful proxy measure for primary productivity, allowing the links between the distributions of animals and resources to be explored. Using NDVI at four spatial resolutions, we here investigate how the distribution of the two sexes in a lek-breeding population of topi antelopes relates to resource abundance before and during the rut. We found that in the dry season preceding the rut, topi density correlated positively with NDVI at the large, but not the fine, scale. This suggests that before the rut, when resources were relatively scant, topi preferred pastures where green grass was widely abundant. The pattern was less pronounced in males, suggesting that the need for territorial attendance prevents males from tracking resources as freely as females do. During the rut, which occurs in the wet season, both male and female densities correlated negatively with NDVI at the fine scale. At this time, resources were generally plentiful and the results suggest that, rather than by resource maximization, distribution during the rut was determined by benefits of aggregating on relatively resource-poor leks for mating, and possibly antipredator, purposes. At the large scale, no correlation between density and NDVI was found during the rut in either sex, which can be explained by leks covering areas too small to be reflected at this resolution. The study illustrates that when investigating spatial organization, it is important: (1) to choose the appropriate analytic scale, and (2) to consider behavioural as well as strictly ecological factors.

  16. Predicting potential distribution of poorly known species with small database: the case of four-horned antelope Tetracerus quadricornis on the Indian subcontinent.

    Science.gov (United States)

    Pokharel, Krishna Prasad; Ludwig, Tobias; Storch, Ilse

    2016-04-01

    Information gaps on the distribution of data deficient and rare species such as four-horned antelope (FHA) in Nepal may impair their conservation. We aimed to empirically predict the distribution of FHA in Nepal with the help of data from the Indian subcontinent. Additionally, we wanted to identify core areas and gaps within the reported range limits and to assess the degree of isolation of known Nepalese populations from the main distribution areas in India. The tropical part of the Indian subcontinent (65°-90° eastern longitude, 5°-30° northern latitude), that is, the areas south of the Himalayan Mountains. Using MaxEnt and accounting for sampling bias, we developed predictive distribution models from environmental and topographical variables, and known presence locations of the study species in India and Nepal. We address and discuss the use of target group vs. random background. The prediction map reveals a disjunct distribution of FHA with core areas in the tropical parts of central to southern-western India. At the scale of the Indian subcontinent, suitable FHA habitat area in Nepal was small. The Indo-Gangetic Plain isolates Nepalese from the Indian FHA populations, but the distribution area extends further south than proposed by the current IUCN map. A low to intermediate temperature seasonality as well as low precipitation during the dry and warm season contributed most to the prediction of FHA distribution. The predicted distribution maps confirm other FHA range maps but also indicate that suitable areas exist south of the known range. Results further highlight that small populations in the Nepalese Terai Arc are isolated from the Indian core distribution and therefore might be under high extinction risk.

  17. Protecting the Lunar Heritage Sites from the Effects of Visiting Spacecraft

    Science.gov (United States)

    Metzger, Philip; Lane, John E.

    2012-01-01

    The Problem: Rocket exhaust blows soil and rocks over vast distances at velocities upwards of 1 to 3 km/s, and this will be highly abrasive and damaging if it impacts the valuable lunar heritage sites.

  18. Technical and educational improvements of the Student Rocket Program at NAROM and Andøya Rocket Range

    Science.gov (United States)

    Nylund, Amund; Rønningen, Jan-Erik

    2007-06-01

    Norwegian Centre for Space-Related Education (NAROM) is co-located with Andøya Rocket Range (ARR) and was established in 2000 as a field station for space-related education. The Student Rocket Program (SRP) was introduced to give the students hands-on experience and a comprehensive introduction to an ordinary scientific rocket launch. NAROM and ARR have since 1998 developed and launched more than 30 student rockets. Since summer 2005 the SRP has been significantly improved with a more powerful rocket motor and a new telemetry system. With these technical improvements, NAROM can introduce new challenges for the students concerning rocket technique, instrumentation, telemetry and data processing. It has also opened possibilities for new pedagogical improvements in terms of a larger curriculum, more use of the ARR infrastructure and making the SRP more adapted to the different participants' qualifications and background. But even though the SRP has been significantly improved during the last years, the program still is in continuously development, making the SRP at NAROM and ARR a unique educational activity for students at different levels of education.

  19. Flutter Analysis of RX-420 Balistic Rocket Fin Involving Rigid Body Modes of Rocket Structures

    Directory of Open Access Journals (Sweden)

    Novi Andria

    2013-03-01

    Full Text Available Flutter is a phenomenon that has brought a catastrophic failure to the flight vehicle structure. In this experiment, flutter was analyzed for its symmetric and antisymmetric configuration to understand the effect of rocket rigid modes to the fin flutter characteristic. This research was also expected to find out the safety level of RX-420 structure design. The analysis was performed using half rocket model. Fin structure used in this research was a fin which has semispan 600 mm, thickness 12 mm, chord root 700 mm, chord tip 400 mm, made by Al 6061-T651, double spar configuration with skin thickness of 2 mm. Structural dynamics and flutter stability were analyzed using finite element software implemented on MSC. Nastran. The analysis shows that the antisymmetric flutter mode is more critical than symmetric flutter mode. At sea level altitude, antisymmetric flutter occurs at 6.4 Mach, and symmetric flutter occurs at 10.15 Mach. Compared to maximum speed of RX-420 which is 4.5 Mach at altitude 11 km or equivalent to 2.1 Mach at sea level, it can be concluded that the RX-420 structure design is safe, and flutter will not occur during flight.

  20. 'RCHX-1-STORM' first Slovenian meteorological rocket program

    Science.gov (United States)

    Kerstein, Aleksander; Matko, Drago; Trauner, Amalija; Britovšek, Zvone

    2004-08-01

    Astronautic and Rocket Society Celje (ARSC) formed a special working team for research and development of a small meteorological hail suppression rocket in the 70th. The hail suppression system was established in former Yugoslavia in the late 60th as an attempt to protect important agricultural regions from one of the summer's most vicious storm. In this time Slovenia was a part of Yugoslavia as one of the federal republic with relative high developed agricultural region production. The Rocket program 'RCHX-STORM' was a second attempt, for Slovenia indigenously developed in the production of meteorological hail suppression rocket. ARSC has designed a family of small sounding rocket that were based on highly promising hybrid propellant propulsion. Hybrid propulsion was selected for this family because it was offering low cost, save production and operation and simple logistics. Conventional sounding rockets use solid propellant motor for their propulsion. The introduction of hybrid motors has enabled a considerable decrease in overall cost. The transportation handling and storage procedures were greatly simplified due to the fact that a hybrid motor was not considered as explosive matter. A hybrid motor may also be designed to stand a severe environment without resorting to conditioning arrangements. The program started in the late 70th when the team ARSC was integrated in the Research and Development Institute in Celje (RDIC). The development program aimed to produce three types of meteorological rockets with diameters 76, 120 and 160 mm. Development of the RCHX-76 engine and rocket vehicle including flight certification has been undertaken by a joint team comprising of the ARCS, RDIC and the company Cestno podjetje Celje (CPC), Road building company Celje. Many new techniques and methods were used in this program such as computer simulation of external and internal ballistics, composite materials for rocket construction, intensive static testing of models and

  1. Landowner and permit-holder perceptions of wildlife damage around the Idaho National Engineering and Environmental Laboratory. A survey of INEEL neighbors about elk, mule deer, pronghorn antelope, and depredation

    Energy Technology Data Exchange (ETDEWEB)

    Roush, D.E. Jr. [Environmental Science and Research Foundation, Inc., Idaho Falls, ID (United States); Beaver, D.E. [Univ. of Idaho, Moscow, ID (United States). Coll. of Forestry, Wildlife, and Range Sciences

    1998-06-01

    Property-owners (N = 220) around the Idaho National Engineering and Environmental Laboratory (INEEL) in southeastern Idaho were surveyed about depredation, control methods and economic issues related to use of the area by elk (Cervus elaphus), mule deer (Odocoileus hemionus), and pronghorn antelope (Antilocapra americana). Depredation was defined as damage to privately-owned crops, forage, and fences and irrigation equipment by these animals. The focus on the three ungulate species was prompted by concerns that elk, which had recolonized the INEEL since 1984, were responsible for an inordinate amount of unprecedented damage to agricultural operations. As the INEEL is a US Department of Energy (DOE) reserve with little public hunting access, there have been calls for removal of elk from this land. This study`s objective was to quantify the wildlife damage occurring on agricultural operations adjacent to the INEEL and to characterize the damage attributed to each big game species. Responses from 70.2% of the target population indicate an evenness of opinion, by which the authors mean that various opinions were represented equitably, toward these animals and wildlife damage Total estimated wildlife damage in 1996 was between $140,000 and $180,000 It was attributed foremost to elk, although pronghorn antelope were viewed nearly as damaging. Respondents placed high values in big game animals and wished to see them continue to inhabit these lands. For managing depredation, adjusting hunting seasons was preferred.

  2. Liquid rocket combustion chamber acoustic characterization

    Directory of Open Access Journals (Sweden)

    Cândido Magno de Souza

    2010-09-01

    Full Text Available Over the last 40 years, many solid and liquid rocket motors have experienced combustion instabilities. Among other causes, there is the interaction of acoustic modes with the combustion and/or fluid dynamic processes inside the combustion chamber. Studies have been showing that, even if less than 1% of the available energy is diverted to an acoustic mode, combustion instability can be generated. On one hand, this instability can lead to ballistic pressure changes, couple with other propulsion systems such as guidance or thrust vector control, and in the worst case, cause motor structural failure. In this case, measures, applying acoustic techniques, must be taken to correct/minimize these influences on the combustion. The combustion chamber acoustic behavior in operating conditions can be estimated by considering its behavior in room conditions. In this way, acoustic tests can be easily performed, thus identifying the cavity modes. This paper describes the procedures to characterize the acoustic behavior in the inner cavity of four different configurations of a combustion chamber. Simple analytical models are used to calculate the acoustic resonance frequencies and these results are compared with acoustic natural frequencies measured at room conditions. Some comments about the measurement procedures are done, as well as the next steps for the continuity of this research. The analytical and experimental procedures results showed good agreement. However, limitations on high frequency band as well as in the identification of specific kinds of modes indicate that numerical methods able to model the real cavity geometry and an acoustic experimental modal analysis may be necessary for a more complete analysis. Future works shall also consider the presence of passive acoustic devices such as baffles and resonators capable of introducing damping and avoiding or limiting acoustic instabilities.

  3. CAC - NUCLEAR THERMAL ROCKET CORE ANALYSIS CODE

    Science.gov (United States)

    Clark, J. S.

    1994-01-01

    One of the most important factors in the development of nuclear rocket engine designs is to be able to accurately predict temperatures and pressures throughout a fission nuclear reactor core with axial hydrogen flow through circular coolant passages. CAC is an analytical prediction program to study the heat transfer and fluid flow characteristics of a circular coolant passage. CAC predicts as a function of time axial and radial fluid conditions, passage wall temperatures, flow rates in each coolant passage, and approximate maximum material temperatures. CAC incorporates the hydrogen properties model STATE to provide fluid-state relations, thermodynamic properties, and transport properties of molecular hydrogen in any fixed ortho-para combination. The program requires the general core geometry, the core material properties as a function of temperature, the core power profile, and the core inlet conditions as function of time. Although CAC was originally developed in FORTRAN IV for use on an IBM 7094, this version is written in ANSI standard FORTRAN 77 and is designed to be machine independent. It has been successfully compiled on IBM PC series and compatible computers running MS-DOS with Lahey F77L, a Sun4 series computer running SunOS 4.1.1, and a VAX series computer running VMS 5.4-3. CAC requires 300K of RAM under MS-DOS, 422K of RAM under SunOS, and 220K of RAM under VMS. No sample executable is provided on the distribution medium. Sample input and output data are included. The standard distribution medium for this program is a 5.25 inch 360K MS-DOS format diskette. CAC was developed in 1966, and this machine independent version was released in 1992. IBM-PC and IBM are registered trademarks of International Business Machines. Lahey F77L is a registered trademark of Lahey Computer Systems, Inc. SunOS is a trademark of Sun Microsystems, Inc. VMS is a trademark of Digital Equipment Corporation. MS-DOS is a registered trademark of Microsoft Corporation.

  4. Rocket experiment on microwave power transmission with Furoshiki deployment

    Science.gov (United States)

    Kaya, Nobuyuki; Iwashita, Masashi; Tanaka, Kohei; Nakasuka, Shinichi; Summerer, Leopold

    2009-07-01

    Huge antennas has many useful applications in space as well as on the ground, for example, Solar Power Satellite to provide electricity to the ground, telecommunication for cellular phones, radars for remote sensing, navigation and observation, and so on. The S-310-36 sounding rocket was successfully launched on 22 January 2006 to verify our newly proposed scheme to construct huge antennas under microgravity condition in space. The rocket experiment has three main objectives, the first objective of which is to verify the Furoshiki deployment system [S. Nakasuka, R. Funase, K. Nakada, N. Kaya, J. Mankins, Large membrane "FUROSHIKI Satellite" applied to phased array antenna and its sounding rocket experiment, in: Proceedings of the 54th International Astronautical Congress, 2003. [1

  5. Probe experiment with RIKI device on a meteorological rocket

    Energy Technology Data Exchange (ETDEWEB)

    Chapknov, S.K.; Ivanova, T.N.; Gusheva, M.N.; Knchev, A.G.; Tsvetkov, Z.I.

    1979-01-01

    The RIKI device carried on board the Centaure-II ionospheric sounding rocket launched on October 31, 1978 from the equatorial rocket base at Tumba, India in order to measure local plasma ion concentrations and temperatures is described. The device consists of a four-spherical-electrode and a three-spherical-electrode spherical ion trap and a block of measuring electronics mounted in the air-tight rocket container. The volt-ampere characteristics of protons traversing a system of concentric grids are determined in fine or coarse resolution as sweeping voltages are supplied to the grids from a sawtooth wave generator. Positive ions which penetrate the grids are collected by the ion trap collectors, and the current generated is used to determine operational modes. Measurements of ion concentration obtained with the RIKI device have been found to be in good agreement with electron concentration measurements obtained concurrently.

  6. Chemical rocket propulsion a comprehensive survey of energetic materials

    CERN Document Server

    Shimada, Toru; Sinditskii, Valery; Calabro, Max

    2017-01-01

    Developed and expanded from the work presented at the New Energetic Materials and Propulsion Techniques for Space Exploration workshop in June 2014, this book contains new scientific results, up-to-date reviews, and inspiring perspectives in a number of areas related to the energetic aspects of chemical rocket propulsion. This collection covers the entire life of energetic materials from their conceptual formulation to practical manufacturing; it includes coverage of theoretical and experimental ballistics, performance properties, as well as laboratory-scale and full system-scale, handling, hazards, environment, ageing, and disposal. Chemical Rocket Propulsion is a unique work, where a selection of accomplished experts from the pioneering era of space propulsion and current technologists from the most advanced international laboratories discuss the future of chemical rocket propulsion for access to, and exploration of, space. It will be of interest to both postgraduate and final-year undergraduate students in...

  7. Vibration Isolation Design for the Micro-X Rocket Payload

    Science.gov (United States)

    Danowski, M. E.; Heine, S. N. T.; Figueroa-Feliciano, E.; Goldfinger, D.; Wikus, P.; McCammon, D.; Oakley, P.

    2016-08-01

    Micro-X is a NASA-funded sounding rocket-borne X-ray imaging spectrometer designed to enable high precision measurements of extended astrophysical systems. To perform high energy resolution measurements and capture unprecedented spectra of supernova remnants and galaxy clusters, Micro-X must maintain tight temperature control. One of the biggest challenges in payload design is to prevent heating of the detectors due to the vibrational loads on the rocket skin during launch. Several stages of vibration damping systems are implemented to prevent energy transmission from the rocket skin to the detector stage, each stage more rigid than the last. We describe recent redesign efforts to improve this vibration isolation by tuning the resonant frequencies of the various stages to minimize heating prior to the projected launch in 2016.

  8. Performance of an Axisymmetric Rocket Based Combined Cycle Engine During Rocket Only Operation Using Linear Regression Analysis

    Science.gov (United States)

    Smith, Timothy D.; Steffen, Christopher J., Jr.; Yungster, Shaye; Keller, Dennis J.

    1998-01-01

    The all rocket mode of operation is shown to be a critical factor in the overall performance of a rocket based combined cycle (RBCC) vehicle. An axisymmetric RBCC engine was used to determine specific impulse efficiency values based upon both full flow and gas generator configurations. Design of experiments methodology was used to construct a test matrix and multiple linear regression analysis was used to build parametric models. The main parameters investigated in this study were: rocket chamber pressure, rocket exit area ratio, injected secondary flow, mixer-ejector inlet area, mixer-ejector area ratio, and mixer-ejector length-to-inlet diameter ratio. A perfect gas computational fluid dynamics analysis, using both the Spalart-Allmaras and k-omega turbulence models, was performed with the NPARC code to obtain values of vacuum specific impulse. Results from the multiple linear regression analysis showed that for both the full flow and gas generator configurations increasing mixer-ejector area ratio and rocket area ratio increase performance, while increasing mixer-ejector inlet area ratio and mixer-ejector length-to-diameter ratio decrease performance. Increasing injected secondary flow increased performance for the gas generator analysis, but was not statistically significant for the full flow analysis. Chamber pressure was found to be not statistically significant.

  9. Iridium-Coated Rhenium Radiation-Cooled Rockets

    Science.gov (United States)

    Reed, Brian D.; Biaglow, James A.; Schneider, Steven J.

    1997-01-01

    Radiation-cooled rockets are used for a range of low-thrust propulsion functions, including apogee insertion, attitude control, and repositioning of satellites, reaction control of launch vehicles, and primary propulsion for planetary space- craft. The key to high performance and long lifetimes for radiation-cooled rockets is the chamber temperature capability. The material system that is currently used for radiation-cooled rockets, a niobium alloy (C103) with a fused silica coating, has a maximum operating temperature of 1370 C. Temperature limitations of C103 rockets force the use of fuel film cooling, which degrades rocket performance and, in some cases, imposes a plume contamination issue from unburned fuel. A material system composed of a rhenium (Re) substrate and an iridium (Ir) coating has demonstrated operation at high temperatures (2200 C) and for long lifetimes (hours). The added thermal margin afforded by iridium-coated rhenium (Ir/Re) allows reduction or elimination of fuel film cooling. This, in turn, leads to higher performance and cleaner spacecraft environments. There are ongoing government- and industry-sponsored efforts to develop flight Ir/ Re engines, with the primary focus on 440-N, apogee insertion engines. Complementing these Ir/Re engine development efforts is a program to address specific concerns and fundamental characterization of the Ir/Re material system, including (1) development of Ir/Re rocket fabrication methods, (2) establishment of critical Re mechanical properly data, (3) development of reliable joining methods, and (4) characterization of Ir/Re life-limiting mechanisms.

  10. Design analysis and risk assessment for a single stage to orbit nuclear thermal rocket

    Science.gov (United States)

    Labib, Satira I.

    Recent advances in high power density fuel materials have renewed interest in nuclear thermal rockets (NTRs) as a viable propulsion technology for future space exploration. This thesis describes the design of three NTR reactor engines designed for the single stage to orbit launch of payloads from 1-15 metric tons. Thermal hydraulic and rocket engine analyses indicate that the proposed rocket engines are able to reach specific impulses in excess of 700 seconds. Neutronics analyses performed using MCNP5 demonstrate that the hot excess reactivity, shutdown margin, and submersion criticality requirements are satisfied for each NTR reactor. The reactors each consist of a 40 cm diameter core packed with hexagonal tungsten cermet fuel elements. The core is surrounded by radial and axial beryllium reflectors and eight boron carbide control drums. At the same power level, the 40 cm reactor results in the lowest radiation dose rate of the three reactors. Radiation dose rates decrease to background levels ~3.5 km from the launch site. After a one-year decay time, all of the activated materials produced by an NTR launch would be classified as Class A low-level waste. The activation of air produces significant amounts of argon-41 and nitrogen-16 within 100 m of the launch. The derived air concentration, DAC, from the activation products decays to less than unity within two days, with only argon-41 remaining. After 10 minutes of full power operation the 120 cm core corresponding to a 15 MT payload contains 2.5 x 1013, 1.4 x 1012, 1.5 x 1012, and 7.8 x 10 7 Bq of 131I, 137Cs, 90Sr, and 239Pu respectively. The decay heat after shutdown increases with increasing reactor power with a maximum decay heat of 108 kW immediately after shutdown for the 15 MT payload.

  11. The Application of Counter-Rotating Turbine in Rocket Turbopump

    Directory of Open Access Journals (Sweden)

    Tang Fei

    2008-01-01

    Full Text Available Counter rotating turbine offers advantages on weight, volume, efficiency, and maneuverability relative to the conventional turbine because of its special architecture. Nowadays, it has been a worldwide research emphasis and has been used widely in the aeronautic field, while its application in the astronautic field is seldom investigated. Researches of counter rotating turbine for rocket turbopump are reviewed in this paper. A primary analysis of a vaneless counter rotating-turbine configuration with rotors of different diameters and rotational speeds is presented. This unconventional configuration meets the requirements of turbopump and may benefit the performance and reliability of rocket engines.

  12. Grooved Fuel Rings for Nuclear Thermal Rocket Engines

    Science.gov (United States)

    Emrich, William

    2009-01-01

    An alternative design concept for nuclear thermal rocket engines for interplanetary spacecraft calls for the use of grooved-ring fuel elements. Beyond spacecraft rocket engines, this concept also has potential for the design of terrestrial and spacecraft nuclear electric-power plants. The grooved ring fuel design attempts to retain the best features of the particle bed fuel element while eliminating most of its design deficiencies. In the grooved ring design, the hydrogen propellant enters the fuel element in a manner similar to that of the Particle Bed Reactor (PBR) fuel element.

  13. Analytical study of nozzle performance for nuclear thermal rockets

    Science.gov (United States)

    Davidian, Kenneth O.; Kacynski, Kenneth J.

    1991-01-01

    A parametric study has been conducted by the NASA-Lewis Rocket Engine Design Expert System for the convergent-divergent nozzle of the Nuclear Thermal Rocket system, which uses a nuclear reactor to heat hydrogen to high temperature and then expands it through the nozzle. It is established by the study that finite-rate chemical reactions lower performance levels from theoretical levels. Major parametric roles are played by chamber temperature and chamber pressure. A maximum performance of 930 sec is projected at 2700 K, and of 1030 at 3100 K.

  14. Nuclear thermal rocket nozzle testing and evaluation program

    Science.gov (United States)

    Davidian, Kenneth O.; Kacynski, Kenneth J.

    1993-01-01

    Performance characteristics of the Nuclear Thermal Rocket can be enhanced through the use of unconventional nozzles as part of the propulsion system. The Nuclear Thermal Rocket nozzle testing and evaluation program being conducted at the NASA Lewis is outlined and the advantages of a plug nozzle are described. A facility description, experimental designs and schematics are given. Results of pretest performance analyses show that high nozzle performance can be attained despite substantial nozzle length reduction through the use of plug nozzles as compared to a convergent-divergent nozzle. Pretest measurement uncertainty analyses indicate that specific impulse values are expected to be within + or - 1.17 pct.

  15. Yuzhnoye's new liquid rocket engines as enablers for space exploration

    Science.gov (United States)

    Degtyarev, Alexander; Kushnaryov, Alexander; Shulga, Vladimir; Ventskovsky, Oleg

    2016-10-01

    Advanced liquid rocket engines (LREs) are being created by Yuzhnoye Design Office of Ukraine based on the fifty-year experience of rocket engines' and propulsion systems' development. These LREs use both hypergolic (NTO+UDMH) and cryogenic (liquid oxygen+kerosene) propellants. First stage engines have a range of thrust from 40 to 250 t, while the upper stage (used in space) engines - from several kilograms to 50 t and a re-ignition feature. The engines are intended for both Ukraine"s independent access to space and international market.

  16. Rocket and laboratory studies in aeronomy and astrophysics

    Science.gov (United States)

    Feldman, P. D.

    1986-01-01

    Progress from March 1, 1986 to August 31, 1986 is covered and includes the work performed in response to a proposal entitled A Spartan Payload for Spatially Resolved Spectroscopy of Extended Faint Sources in the Extreme Ultraviolet (EUV). During this period, one rocket was launched, the reflight of the payload to observe Halley's comet on March 13, 1986. Most of the effort during this period was concentrated on detailed mechanical and electronic design of a Spartan payload and on the reduction and analysis of the data from the two Halley rocket flights and from the UVX experiment which flew on STS-61C in January 1986.

  17. Rocket and laboratory studies in aeronomy and astronomy

    Science.gov (United States)

    Feldman, P. D.

    1983-01-01

    Data extracted from semi-annual status reports presented include: a list of all sounding rocket launches performed under NASA sponsorship; a list of Ph.D. and M.A. degrees awarded to students who worked in these programs; a summary bibliography of all publications through 1983; the most recent list of the publications from the IUE program; a summary of instrument development supported by the Johns Hopkins sounding rocket program; and a list of faculty and post-doctoral research associates whose work was supported by this grant.

  18. Effects of high combustion chamber pressure on rocket noise environment

    Science.gov (United States)

    Pao, S. P.

    1972-01-01

    The acoustical environment for a high combustion chamber pressure engine was examined in detail, using both conventional and advanced theoretical analysis. The influence of elevated chamber pressure on the rocket noise environment was established, based on increase in exit velocity and flame temperature, and changes in basic engine dimensions. Compared to large rocket engines, the overall sound power level is found to be 1.5 dB higher, if the thrust is the same. The peak Strouhal number shifted about one octave lower to a value near 0.01. Data on apparent sound source location and directivity patterns are also presented.

  19. Rocket Plume Scaling for Orion Wind Tunnel Testing

    Science.gov (United States)

    Brauckmann, Gregory J.; Greathouse, James S.; White, Molly E.

    2011-01-01

    A wind tunnel test program was undertaken to assess the jet interaction effects caused by the various solid rocket motors used on the Orion Launch Abort Vehicle (LAV). These interactions of the external flowfield and the various rocket plumes can cause localized aerodynamic disturbances yielding significant and highly non-linear control amplifications and attenuations. This paper discusses the scaling methodologies used to model the flight plumes in the wind tunnel using cold air as the simulant gas. Comparisons of predicted flight, predicted wind tunnel, and measured wind tunnel forces-and-moments and plume flowfields are made to assess the effectiveness of the selected scaling methodologies.

  20. Heat exchanger. [rocket combustion chambers and cooling systems

    Science.gov (United States)

    Sokolowski, D. E. (Inventor)

    1978-01-01

    A heat exchanger, as exemplified by a rocket combustion chamber, is constructed by stacking thin metal rings having microsized openings therein at selective locations to form cooling passages defined by an inner wall, an outer wall and fins. Suitable manifolds are provided at each end of the rocket chamber. In addition to the cooling channel openings, coolant feed openings may be formed in each of rings. The coolant feed openings may be nested or positioned within generally U-shaped cooling channel openings. Compression on the stacked rings may be maintained by welds or the like or by bolts extending through the stacked rings.

  1. Magnetic resonance imaging (MRI) of solid rocket components

    Energy Technology Data Exchange (ETDEWEB)

    Wallner, A.S. [Missouri Western State College, St. Joseph, MO (United States); Nissan, R.A.; Merwin, L.H. [Naval Air Warfare Center, China Lake, CA (United States)] [and others

    1995-12-01

    The evaluation of solid rocket components has become an area of great interest. Studying these materials with MRI offers a great advantage to observe knit lines, regions of inhomogeneity, voids, defects, plasticizer rich/poor areas and solids distribution because of the nondestructive nature of the technique. Aspects of sample preparation, spectroscopic relaxation studies, and MRI as a method of studying these systems will be discussed. Initial images show the ability to image propellant, liner, and explosive materials with an in-plane resolution of 70 {mu}m/pixel. These initial images show that MRI can be developed as a viable nondestructive evaluation method of solid rocket components.

  2. Nuclear Rocket Facility Decommissioning Project: Controlled Explosive Demolition of Neutron-Activated Shield Wall

    Energy Technology Data Exchange (ETDEWEB)

    Michael R. Kruzic

    2008-06-01

    Located in Area 25 of the Nevada Test Site (NTS), the Test Cell A (TCA) Facility (Figure 1) was used in the early to mid-1960s for testing of nuclear rocket engines, as part of the Nuclear Rocket Development Program, to further space travel. Nuclear rocket testing resulted in the activation of materials around the reactors and the release of fission products and fuel particles. The TCA facility, known as Corrective Action Unit 115, was decontaminated and decommissioned (D&D) from December 2004 to July 2005 using the Streamlined Approach for Environmental Restoration (SAFER) process, under the Federal Facility Agreement and Consent Order. The SAFER process allows environmental remediation and facility closure activities (i.e., decommissioning) to occur simultaneously, provided technical decisions are made by an experienced decision maker within the site conceptual site model. Facility closure involved a seven-step decommissioning strategy. First, preliminary investigation activities were performed, including review of process knowledge documentation, targeted facility radiological and hazardous material surveys, concrete core drilling and analysis, shield wall radiological characterization, and discrete sampling, which proved to be very useful and cost-effective in subsequent decommissioning planning and execution and worker safety. Second, site setup and mobilization of equipment and personnel were completed. Third, early removal of hazardous materials, including asbestos, lead, cadmium, and oil, was performed ensuring worker safety during more invasive demolition activities. Process piping was to be verified void of contents. Electrical systems were de-energized and other systems were rendered free of residual energy. Fourth, areas of high radiological contamination were decontaminated using multiple methods. Contamination levels varied across the facility. Fixed beta/gamma contamination levels ranged up to 2 million disintegrations per minute (dpm)/100

  3. The sky is falling: chemical characterization and corrosion evaluation of deposition produced during the static testing of solid rocket motors.

    Science.gov (United States)

    Doucette, William J; McNeill, Laurie S; Mendenhall, Scout; Hancock, Paul V; Wells, Jason E; Thackeray, Kevin J; Gosen, David P

    2013-03-01

    Static tests of horizontally restrained rocket motors at the ATK facility in Promontory UT, USA result in the deposition of entrained soil and fuel combustion products, referred to as Test Fire Soil (TFS), over areas as large as 30-50 mile (80-130 km) and at distances up to 10-12 miles (16-20 km) from the test site. Chloride is the main combustion product generated from the ammonium perchlorate-aluminum based composite propellant. Deposition sampling/characterization and a 6-month field corrosivity study using mild steel coupons were conducted in conjunction with the February 25th 2010 FSM-17 static test. The TFS deposition rates at the three study sites ranged from 1 to 5 g/min/m. TFS contained significantly more chloride than the surface soil collected from the test site. The TFS collected during two subsequent tests had similarly elevated chloride, suggesting that the results obtained in this study are applicable to other tests assuming that the rocket fuel composition remains similar. The field-deployed coupons exposed to the TFS had higher corrosion rates (3.6-5.0 mpy) than paired non-exposed coupons (1.6-1.8 mpy). Corrosion rates for all coupons decreased over time, but coupons exposed to the TFS always had a higher rate than the non-exposed. Differences in corrosion rates between the three study sites were also observed, with sites receiving more TFS deposition having higher corrosion rates.

  4. Pulse Detonation Rocket MHD Power Experiment

    Science.gov (United States)

    Litchford, Ron J.; Cook, Stephen (Technical Monitor)

    2002-01-01

    A pulse detonation research engine (MSFC (Marshall Space Flight Center) Model PDRE (Pulse Detonation Rocket Engine) G-2) has been developed for the purpose of examining integrated propulsion and magnetohydrodynamic power generation applications. The engine is based on a rectangular cross-section tube coupled to a converging-diverging nozzle, which is in turn attached to a segmented Faraday channel. As part of the shakedown testing activity, the pressure wave was interrogated along the length of the engine while running on hydrogen/oxygen propellants. Rapid transition to detonation wave propagation was insured through the use of a short Schelkin spiral near the head of the engine. The measured detonation wave velocities were in excess of 2500 m/s in agreement with the theoretical C-J velocity. The engine was first tested in a straight tube configuration without a nozzle, and the time resolved thrust was measured simultaneously with the head-end pressure. Similar measurements were made with the converging-diverging nozzle attached. The time correlation of the thrust and head-end pressure data was found to be excellent. The major purpose of the converging-diverging nozzle was to configure the engine for driving an MHD generator for the direct production of electrical power. Additional tests were therefore necessary in which seed (cesium-hydroxide dissolved in methanol) was directly injected into the engine as a spray. The exhaust plume was then interrogated with a microwave interferometer in an attempt to characterize the plasma conditions, and emission spectroscopy measurements were also acquired. Data reduction efforts indicate that the plasma exhaust is very highly ionized, although there is some uncertainty at this time as to the relative abundance of negative OH ions. The emission spectroscopy data provided some indication of the species in the exhaust as well as a measurement of temperature. A 24-electrode-pair segmented Faraday channel and 0.6 Tesla permanent

  5. Pulse Detonation Rocket MHD Power Experiment

    Science.gov (United States)

    Litchford, Ron J.; Cook, Stephen (Technical Monitor)

    2002-01-01

    A pulse detonation research engine (MSFC (Marshall Space Flight Center) Model PDRE (Pulse Detonation Rocket Engine) G-2) has been developed for the purpose of examining integrated propulsion and magnetohydrodynamic power generation applications. The engine is based on a rectangular cross-section tube coupled to a converging-diverging nozzle, which is in turn attached to a segmented Faraday channel. As part of the shakedown testing activity, the pressure wave was interrogated along the length of the engine while running on hydrogen/oxygen propellants. Rapid transition to detonation wave propagation was insured through the use of a short Schelkin spiral near the head of the engine. The measured detonation wave velocities were in excess of 2500 m/s in agreement with the theoretical C-J velocity. The engine was first tested in a straight tube configuration without a nozzle, and the time resolved thrust was measured simultaneously with the head-end pressure. Similar measurements were made with the converging-diverging nozzle attached. The time correlation of the thrust and head-end pressure data was found to be excellent. The major purpose of the converging-diverging nozzle was to configure the engine for driving an MHD generator for the direct production of electrical power. Additional tests were therefore necessary in which seed (cesium-hydroxide dissolved in methanol) was directly injected into the engine as a spray. The exhaust plume was then interrogated with a microwave interferometer in an attempt to characterize the plasma conditions, and emission spectroscopy measurements were also acquired. Data reduction efforts indicate that the plasma exhaust is very highly ionized, although there is some uncertainty at this time as to the relative abundance of negative OH ions. The emission spectroscopy data provided some indication of the species in the exhaust as well as a measurement of temperature. A 24-electrode-pair segmented Faraday channel and 0.6 Tesla permanent

  6. The seven secrets of how to think like a rocket scientist

    CERN Document Server

    Longuski, James

    2007-01-01

    This book explains the methods that rocket scientists use - expressed in a way that could be applied in everyday life. It's short and snappy and written by a rocket scientist. It is intended for general "armchair" scientists.

  7. Rocket motors incorporating basalt fiber and nanoclay compositions and methods of insulating a rocket motor with the same

    Science.gov (United States)

    Gajiwala, Himansu M. (Inventor)

    2011-01-01

    An insulation composition that comprises at least one nitrile butadiene rubber, basalt fibers, and nanoclay is disclosed. Further disclosed is an insulation composition that comprises polybenzimidazole fibers, basalt fibers, and nanoclay. The basalt fibers may be present in the insulation compositions in a range of from approximately 1% by weight to approximately 6% by weight of the total weight of the insulation composition. The nanoclay may be present in the insulation compositions in a range of from approximately 5% by weight to approximately 10% by weight of the total weight of the insulation composition. Rocket motors including the insulation compositions and methods of insulating a rocket motor are also disclosed.

  8. Rocket-Plume Spectroscopy Simulation for Hydrocarbon-Fueled Rocket Engines

    Science.gov (United States)

    Tejwani, Gopal D.

    2010-01-01

    The UV-Vis spectroscopic system for plume diagnostics monitors rocket engine health by using several analytical tools developed at Stennis Space Center (SSC), including the rocket plume spectroscopy simulation code (RPSSC), to identify and quantify the alloys from the metallic elements observed in engine plumes. Because the hydrocarbon-fueled rocket engine is likely to contain C2, CO, CH, CN, and NO in addition to OH and H2O, the relevant electronic bands of these molecules in the spectral range of 300 to 850 nm in the RPSSC have been included. SSC incorporated several enhancements and modifications to the original line-by-line spectral simulation computer program implemented for plume spectral data analysis and quantification in 1994. These changes made the program applicable to the Space Shuttle Main Engine (SSME) and the Diagnostic Testbed Facility Thruster (DTFT) exhaust plume spectral data. Modifications included updating the molecular and spectral parameters for OH, adding spectral parameter input files optimized for the 10 elements of interest in the spectral range from 320 to 430 nm and linking the output to graphing and analysis packages. Additionally, the ability to handle the non-uniform wavelength interval at which the spectral computations are made was added. This allowed a precise superposition of wavelengths at which the spectral measurements have been made with the wavelengths at which the spectral computations are done by using the line-by-line (LBL) code. To account for hydrocarbon combustion products in the plume, which might interfere with detection and quantification of metallic elements in the spectral region of 300 to 850 nm, the spectroscopic code has been enhanced to include the carbon-based combustion species of C2, CO, and CH. In addition, CN and NO have spectral bands in 300 to 850 nm and, while these molecules are not direct products of hydrocarbon-oxygen combustion systems, they can show up if nitrogen or a nitrogen compound is present

  9. Damage assessment of long-range rocket system by electromagnetic pulse weapon

    Science.gov (United States)

    Cao, Lingyu; Liu, Guoqing; Li, Jinming

    2017-08-01

    This paper analyzes the damage mechanism and characteristics of electromagnetic pulse weapon, establishes the index system of survivability of long-range rocket launcher system, and uses AHP method to establish the combat effectiveness model of long-range rocket missile system. According to the damage mechanism and characteristics of electromagnetic pulse weapon, the damage effect of the remote rocket system is established by using the exponential method to realize the damage efficiency of the remote rocket system.

  10. Initial risk assessment for a single stage to orbit nuclear thermal rocket

    Energy Technology Data Exchange (ETDEWEB)

    Labib, Satira, E-mail: Satira.Labib@duke-energy.com; King, Jeffrey, E-mail: kingjc@mines.edu

    2015-06-15

    Highlights: • The risks posed by the surface launch of a nuclear thermal rocket are considered. • Radiation exposure at the public viewing distance is insignificant. • Production of fission products and actinides during launch is limited. • The production of activated argon around the rocket may be a significant concern. - Abstract: In order to consider the possibility of a nuclear thermal rocket (NTR) ground launch, it is necessary to evaluate the risks from such a launch. This includes analysis of the radiation dose rate around the rocket, determining the rate of activation of the materials near the launch, and considering the radionuclides present in the core after the launch. This paper evaluates the potential risk of the NTR ground launch for a range of payloads from 1 to 15 metric tons (MT) using three NTR reactor cores (40, 80, and 120 cm in length) designed in a previous study, based on data produced by MCNP5 and MCNPX models. At the same power level, the 40 cm core length reactor results in the lowest radiation dose rate of the three reactors. Radiation dose rates decrease to background levels 3.5 km from the launch site. After a 1-year decay time, all of the activated materials produced by an NTR launch would be classified as Class A low-level waste. The activation of air produces significant amounts of argon-41 and nitrogen-16 within 100 m of the launch. The derived air concentration (DAC) ratio of the activation products decays to less than unity within 2 days, with only argon-41 remaining. After 10 min of full power operation, the 120 cm core for a 15 MT payload contains 2.5 × 10{sup 13}, 1.4 × 10{sup 12} and 1.5 × 10{sup 12} Bq of {sup 131}I, {sup 137}Cs, and {sup 90}Sr, respectively. The decay heat after shutdown increases with increasing reactor power with a maximum decay heat of 108 kW immediately after shutdown for the 15 MT payload.

  11. How High? How Fast? How Long? Modeling Water Rocket Flight with Calculus

    Science.gov (United States)

    Ashline, George; Ellis-Monaghan, Joanna

    2006-01-01

    We describe an easy and fun project using water rockets to demonstrate applications of single variable calculus concepts. We provide procedures and a supplies list for launching and videotaping a water rocket flight to provide the experimental data. Because of factors such as fuel expulsion and wind effects, the water rocket does not follow the…

  12. How High? How Fast? How Long? Modeling Water Rocket Flight with Calculus

    Science.gov (United States)

    Ashline, George; Ellis-Monaghan, Joanna

    2006-01-01

    We describe an easy and fun project using water rockets to demonstrate applications of single variable calculus concepts. We provide procedures and a supplies list for launching and videotaping a water rocket flight to provide the experimental data. Because of factors such as fuel expulsion and wind effects, the water rocket does not follow the…

  13. Ionospheric effects of whistler waves from rocket-triggered lightning

    Science.gov (United States)

    Cotts, B. R. T.; Gołkowski, M.; Moore, R. C.

    2011-12-01

    Lightning-induced electron precipitation (LEP) is one of the primary mechanisms for energetic electron loss from Earth's radiation belts. While previous works have emphasized lightning location and the return stroke peak current in quantifying lightning's role in radiation belt electron loss, the spectrum of the lightning return stroke has received far less attention. Rocket-triggered lightning experiments performed at the International Center for Lightning Research and Testing (ICLRT) at Camp Blanding, Florida, provide a means to directly measure the spectral content of individual lightning return strokes. Using an integrated set of numerical models and directly observed rocket-triggered lightning channel-base currents we calculate the latitudinal dependence of the precipitation signature. Model results indicate that rocket-triggered lightning may produce detectable LEP events and that return strokes with higher ELF (3 Hz-3 kHz) content cause proportionally more ionospheric ionization and precipitate more electrons at higher latitudes than return strokes with proportionally higher VLF (3 kHz-30 kHz) content. The predicted spatio-temporal signature of the induced electron precipitation is highly dependent upon the return stroke spectral content. As a result, we postulate that rocket-triggered lightning experiments enable us to the estimate the spectral profile of energetic electrons precipitated from the Earth's radiation belts.

  14. Rocket Scientist for a Day: Investigating Alternatives for Chemical Propulsion

    Science.gov (United States)

    Angelin, Marcus; Rahm, Martin; Gabrielsson, Erik; Gumaelius, Lena

    2012-01-01

    This laboratory experiment introduces rocket science from a chemistry perspective. The focus is set on chemical propulsion, including its environmental impact and future development. By combining lecture-based teaching with practical, theoretical, and computational exercises, the students get to evaluate different propellant alternatives. To…

  15. 77 FR 50584 - Voluntary Licensing of Amateur Rocket Operations

    Science.gov (United States)

    2012-08-22

    ... are summarized below. Total Benefits and Costs The FAA does not require licensing of amateur rocket... of this rule. To the extent the licensing requirements provide a societal benefit, those benefits... Federal Aviation Administration 14 CFR Part 400 RIN 2120-AJ84 Voluntary Licensing of Amateur...

  16. Ultrasonic investigation of mechanical properties of double base rocket propellants

    NARCIS (Netherlands)

    Schroeff, J.A. van der; Boer, R.S. de

    1976-01-01

    For a series of double base rocket propellants and for poly-methylmethacrylate (PMMA) the longitudinal and transverse sound wave velocities are measured at a frequency of 0.351 MHz in t h e temperature range of −40°C to +60°C. The relations between these acoustic properties and mechanical properties

  17. First results of the Auroral Turbulance II rocket experiment

    DEFF Research Database (Denmark)

    Danielides, M.A.; Ranta, A.; Ivchenco, N.

    1999-01-01

    The Auroral Turbulance II sounding rocket was launched on February 11, 1997 into moderately active nightside aurora from the Poker Flat Research Range, Alaska, US. The experiment consisted of three independent, completely instrumented payloads launched by a single vehicle. The aim of the experiment...

  18. Comet mission is blown off course by faulty rocket

    CERN Multimedia

    Henderson, M

    2003-01-01

    ESA has announced that the launch of the Rosetta probe, has been delayed indefinitely because of problems with the unreliable Ariane-5 rocket on which it was to fly. The project will now have to be redesigned completely to target a different comet at a later date (1/2 page).

  19. Study of Rapid-Regression Liquefying Hybrid Rocket Fuels

    Science.gov (United States)

    Zilliac, Greg; DeZilwa, Shane; Karabeyoglu, M. Arif; Cantwell, Brian J.; Castellucci, Paul

    2004-01-01

    A report describes experiments directed toward the development of paraffin-based hybrid rocket fuels that burn at regression rates greater than those of conventional hybrid rocket fuels like hydroxyl-terminated butadiene. The basic approach followed in this development is to use materials such that a hydrodynamically unstable liquid layer forms on the melting surface of a burning fuel body. Entrainment of droplets from the liquid/gas interface can substantially increase the rate of fuel mass transfer, leading to surface regression faster than can be achieved using conventional fuels. The higher regression rate eliminates the need for the complex multi-port grain structures of conventional solid rocket fuels, making it possible to obtain acceptable performance from single-port structures. The high-regression-rate fuels contain no toxic or otherwise hazardous components and can be shipped commercially as non-hazardous commodities. Among the experiments performed on these fuels were scale-up tests using gaseous oxygen. The data from these tests were found to agree with data from small-scale, low-pressure and low-mass-flux laboratory tests and to confirm the expectation that these fuels would burn at high regression rates, chamber pressures, and mass fluxes representative of full-scale rocket motors.

  20. Two phase flow combustion modelling of a ducted rocket

    NARCIS (Netherlands)

    Stowe, R.A.; Dubois, C.; Harris, P.G.; Mayer, A.E.H.J.; Champlain, A. de; Ringuette, S.

    2001-01-01

    Under a co-operative program, the Defence Research Establishment Valcartier and Université Laval in Canada and the TNO Prins Maurits Laboratory in the Netherlands have studied the use of a ducted rocket for missile propulsion. Hot-flow direct-connect combustion experiments using both simulated and s

  1. Stratospheric aluminum oxide. [possibly from solid-fuel rocket exhausts

    Science.gov (United States)

    Brownlee, D. E.; Tomandl, D.; Ferry, G. V.

    1976-01-01

    Balloons and U-2 aircraft were used to collect micrometer-sized stratospheric aerosols. It was discovered that for the past 6 years at least, aluminum oxide spheres have been the major stratospheric particulate in the size range from 3 to 8 micrometers. The most probable source of the spheres is the exhaust from solid-fuel rockets.

  2. U.S./CIS eye joint nuclear rocket venture

    Science.gov (United States)

    Clark, John S.; Mcilwain, Melvin C.; Smetanikov, Vladimir; D'Yakov, Evgenij K.; Pavshuk, Vladimir A.

    1993-01-01

    An account is given of the significance for U.S. spacecraft development of a nuclear thermal rocket (NTR) reactor concept that has been developed in the (formerly Soviet) Commonwealth of Independent States (CIS). The CIS NTR reactor employs a hydrogen-cooled zirconium hydride moderator and ternary carbide fuels; the comparatively cool operating temperatures associated with this design promise overall robustness.

  3. U.S./CIS eye joint nuclear rocket venture

    Science.gov (United States)

    Clark, John S.; McIlwain, Melvin C.; Smetanikov, Vladimir; D'Yakov, Evgenij K.; Pavshuk, Vladimir A.

    1993-07-01

    An account is given of the significance for U.S. spacecraft development of a nuclear thermal rocket (NTR) reactor concept that has been developed in the (formerly Soviet) Commonwealth of Independent States (CIS). The CIS NTR reactor employs a hydrogen-cooled zirconium hydride moderator and ternary carbide fuels; the comparatively cool operating temperatures associated with this design promise overall robustness.

  4. Study of Liquid Breakup Process in Solid Rocket Motor Nozzle

    Science.gov (United States)

    2016-02-16

    34Chemical Erosion of Refractory - Metal Nozzle Inserts in Solid-Propellant Rocket Motors," J. Propulsion and Power, Vol. 25, no.1,, 2009. [4] E. Y. Wong...Paul A.;, "Gelcasting of Alumina," J. Am. Ceram . Soc. 74[3], pp. 612-618, 1991. [18] Blomquist , B. A.; Fink, J. K.; Leibowitz, L.;, "The

  5. Burn Rate Modelling of Solid Rocket Propellants (Short Communication

    Directory of Open Access Journals (Sweden)

    A.R. Kulkarni

    1998-01-01

    Full Text Available A generalised model of burning of a solid rocket propellant based on kinetics of propellant hasbeen developed. A complete set of variables has been formed after examining the existing models.Buckingham theorem provides the functional form of the model, such that the existing models are thesubcases of this generalised model. This proposed model has been validated by an experimental data.

  6. Residual velocities in combustion experiments on board of sounding rockets

    Science.gov (United States)

    Juste, G. L.

    1996-12-01

    Most combustion experiments on microgravity conditions require extensive testing time, thus making necessary the use of sounding rockets, satellites and spatial laboratories. Sounding rockets and satellites offer some advantages over spatial laboratories, i.e. less strict safety requirements than those in manned flights, the cost of the experiment is also lower. In combustion experiments, the gas velocities inside test modules must be smaller than the characteristic velocity of the process. The initial spin stabilization of sounding rockets has been identified as a possible origin of residual velocities inside the aforementioned modules. The object of the present work is to study the gas residual velocity in the module designed by SENER for carrying out of combustion experiments in microgravity conditions in sounding rockets. Particle image velocimetry was used to measure these velocities. The study shows that, after the spin stabilization, a rapid slowing down of such velocities is produced, decreasing by 5 mm/s after 10 s and down to 0.1 mm/s after 40 s.

  7. The Effect of Resistance on Rocket Injector Acoustics

    Science.gov (United States)

    Morgan, C. J.

    2015-01-01

    Combustion instability, where unsteady heat release couples with acoustic modes, has long been an area of concern in liquid rocket engines. Accurate modeling of the acoustic normal modes of the combustion chamber is important to understanding and preventing combustion instability. The injector resistance can have a significant influence on the chamber normal mode shape, and hence on the system stability.

  8. Metallic hydrogen: The most powerful rocket fuel yet to exist

    Energy Technology Data Exchange (ETDEWEB)

    Silvera, Isaac F [Lyman Laboratory of Physics, Harvard University, Cambridge MA 02138 (United States); Cole, John W, E-mail: silvera@physics.harvard.ed [NASA MSFC, Huntsville, AL 35801 (United States)

    2010-03-01

    Wigner and Huntington first predicted that pressures of order 25 GPa were required for the transition of solid molecular hydrogen to the atomic metallic phase. Later it was predicted that metallic hydrogen might be a metastable material so that it remains metallic when pressure is released. Experimental pressures achieved on hydrogen have been more than an order of magnitude higher than the predicted transition pressure and yet it remains an insulator. We discuss the applications of metastable metallic hydrogen to rocketry. Metastable metallic hydrogen would be a very light-weight, low volume, powerful rocket propellant. One of the characteristics of a propellant is its specific impulse, I{sub sp}. Liquid (molecular) hydrogen-oxygen used in modern rockets has an Isp of {approx}460s; metallic hydrogen has a theoretical I{sub sp} of 1700s. Detailed analysis shows that such a fuel would allow single-stage rockets to enter into orbit or carry economical payloads to the moon. If pure metallic hydrogen is used as a propellant, the reaction chamber temperature is calculated to be greater than 6000 K, too high for currently known rocket engine materials. By diluting metallic hydrogen with liquid hydrogen or water, the reaction temperature can be reduced, yet there is still a significant performance improvement for the diluted mixture.

  9. Implementation of microwave transmissions for rocket exhaust plume diagnostics

    Science.gov (United States)

    Coutu, Nicholas George

    Rocket-launched vehicles produce a trail of exhaust that contains ions, free electrons, and soot. The exhaust plume increases the effective conductor length of the rocket. A conductor in the presence of an electric field (e.g. near the electric charge stored within a cloud) can channel an electric discharge. The electrical conductivity of the exhaust plume is related to its concentration of free electrons. The risk of a lightning strike in-flight is a function of both the conductivity of the body and its effective length. This paper presents an approach that relates the electron number density of the exhaust plume to its propagation constant. Estimated values of the collision frequency and electron number density generated from a numerical simulation of a rocket plume are used to guide the design of the experimental apparatus. Test par meters are identified for the apparatus designed to transmit a signal sweep form 4 GHz to 7 GHz through the exhaust plume of a J-class solid rocket motor. Measurements of the scattering parameters imply that the transmission does not penetrate the plume, but instead diffracts around it. The electron density 20 cm downstream from the nozzle exit is estimated to be between 2.7x1014 m--3 and 5.6x10 15 m--3.

  10. STS-27 Atlantis, OV-104, solid rocket booster (SRB) inspection

    Science.gov (United States)

    1988-01-01

    Engineers, kneeling inside a hollow solid rocket booster (SRB), closely inspect the SRB segments and seams in the Kennedy Space Center (KSC) rotation and processing facility. The SRB will be used on STS-27 Atlantis, Orbiter Vehicle (OV) 104. The booster segments were transported via rail car from Morton Thiokol's Utah manufacturing plant. View provided by KSC with alternate number KSC-88PC-492.

  11. In-flight calibration of mesospheric rocket plasma probes.

    Science.gov (United States)

    Havnes, Ove; Hartquist, Thomas W; Kassa, Meseret; Morfill, Gregor E

    2011-07-01

    Many effects and factors can influence the efficiency of a rocket plasma probe. These include payload charging, solar illumination, rocket payload orientation and rotation, and dust impact induced secondary charge production. As a consequence, considerable uncertainties can arise in the determination of the effective cross sections of plasma probes and measured electron and ion densities. We present a new method for calibrating mesospheric rocket plasma probes and obtaining reliable measurements of plasma densities. This method can be used if a payload also carries a probe for measuring the dust charge density. It is based on that a dust probe's effective cross section for measuring the charged component of dust normally is nearly equal to its geometric cross section, and it involves the comparison of variations in the dust charge density measured with the dust detector to the corresponding current variations measured with the electron and/or ion probes. In cases in which the dust charge density is significantly smaller than the electron density, the relation between plasma and dust charge density variations can be simplified and used to infer the effective cross sections of the plasma probes. We illustrate the utility of the method by analysing the data from a specific rocket flight of a payload containing both dust and electron probes.

  12. Adventures in Rocket Science. EG-2007-12-179-MSFC

    Science.gov (United States)

    Huegele, Vince; Hill, Kristy; Terry, Brenda

    2008-01-01

    This guide was prepared as a tool useful for informal education venues (4-H, Boys and Girls Clubs, Boy Scouts, Girl Scouts, etc.), science clubs and related programs, and can be adopted for formal education settings. An exciting and productive study in rocket science can be implemented using the selected activities for the above-mentioned…

  13. Berkeley extreme-ultraviolet airglow rocket spectrometer - BEARS

    Science.gov (United States)

    Cotton, D. M.; Chakrabarti, S.

    1992-01-01

    The Berkeley EUV airglow rocket spectrometer (BEARS) instrument is described. The instrument was designed in particular to measure the dominant lines of atomic oxygen in the FUV and EUV dayglow at 1356, 1304, 1027, and 989 A, which is the ultimate source of airglow emissions. The optical and mechanical design of the instrument, the detector, electronics, calibration, flight operations, and results are examined.

  14. Rocket Scientist for a Day: Investigating Alternatives for Chemical Propulsion

    Science.gov (United States)

    Angelin, Marcus; Rahm, Martin; Gabrielsson, Erik; Gumaelius, Lena

    2012-01-01

    This laboratory experiment introduces rocket science from a chemistry perspective. The focus is set on chemical propulsion, including its environmental impact and future development. By combining lecture-based teaching with practical, theoretical, and computational exercises, the students get to evaluate different propellant alternatives. To…

  15. Management Qua Communication in Rocket Research and Development

    Science.gov (United States)

    Tompkins, Phillip K.

    1977-01-01

    Reviews a diagnostic study conducted by a communication consultant within the George C Marshall Space Flight Center during the research and development of the Saturn V or "Moon Rocket". Participant observation and in-depth interview methodology yields information on organizational communication and systematic problems within a complex network. (MH)

  16. Radiation/convection coupling in rocket motors and plumes

    Science.gov (United States)

    Farmer, R. C.; Saladino, A. J.

    1993-07-01

    The three commonly used propellant systems - H2/O2, RP-1/O2, and solid propellants - primarily radiate as molecular emitters, non-scattering small particles, and scattering larger particles, respectively. Present technology has accepted the uncoupling of the radiation analysis from that of the flowfield. This approximation becomes increasingly inaccurate as one considers plumes, interior rocket chambers, and nuclear rocket propulsion devices. This study will develop a hierarchy of methods which will address radiation/convection coupling in all of the aforementioned propulsion systems. The nature of the radiation/convection coupled problem is that the divergence of the radiative heat flux must be included in the energy equation and that the local, volume-averaged intensity of the radiation must be determined by a solution of the radiative transfer equation (RTE). The intensity is approximated by solving the RTE along several lines of sight (LOS) for each point in the flowfield. Such a procedure is extremely costly; therefore, further approximations are needed. Modified differential approximations are being developed for this purpose. It is not obvious which order of approximations are required for a given rocket motor analysis. Therefore, LOS calculations have been made for typical rocket motor operating conditions in order to select the type approximations required. The results of these radiation calculations, and the interpretation of these intensity predictions are presented herein.

  17. Characterization of abandoned rocket body families for active removal

    Science.gov (United States)

    Pardini, Carmen; Anselmo, Luciano

    2016-09-01

    A new ranking index was developed and applied to a wide set of rocket body families, characterized by stage dry masses greater than 500 kg and by the presence of at least 5 stages abandoned in LEO. The upper stages selected accounted for more than 80% of the unclassified rocket bodies in LEO and nearly 95% of the associated dry mass. The detailed results obtained for 657 objects clearly identified the most critical altitude-inclination bands and stage models, to be targeted first if and when a debris remediation strategy including the active removal of intact abandoned objects were deemed necessary. Apart from the evaluation of the criticality regarding the long-term evolution of the debris environment, resulting in a priority listing for optimal active removal, the application of the new ranking index is not limited to debris remediation. In fact, if applied before launch to spacecraft and rocket bodies to be disposed in orbit, at the end of mission, it would provide an additional debris mitigation analysis tool for evaluating competing disposal options. Concerning the rocket bodies abandoned in LEO, 274 resulted to have a criticality equal or larger than the average intact object abandoned in an 800 km sun-synchronous orbit. Among them, 243 belonged to the Russian Federation and Ukraine, 25 to China, 5 to Europe and 1 to Japan. In addition to being concentrated in relatively few and narrow altitude-inclinations bands, the most numerous rocket body families often present a quite uniform distribution in right ascension of the ascending node, which is especially convenient for multiple target removal missions.

  18. Advanced reservoir characterization in the Antelope Shale to establish the viability of CO2 enhanced oil recovery in California`s Monterey Formation siliceous shales. Annual report, February 7, 1997--February 6, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Morea, M.F.

    1998-06-01

    The primary objective of this research is to conduct advanced reservoir characterization and modeling studies in the Antelope Shale reservoir. Characterization studies will be used to determine the technical feasibility of implementing a CO{sub 2} enhanced oil recovery project in the antelope Shale in Buena Vista Hills Field. The proposed pilot consists of four existing producers on 20 acre spacing with a new 10 acre infill well drilled as the pilot CO{sub 2} injector. Most of the reservoir characterization during Phase 1 of the project will be performed using data collected in the pilot pattern wells. During this period the following tasks have been completed: laboratory wettability; specific permeability; mercury porosimetry; acoustic anisotropy; rock mechanics analysis; core description; fracture analysis; digital image analysis; mineralogical analysis; hydraulic flow unit analysis; petrographic and confocal thin section analysis; oil geochemical fingerprinting; production logging; carbon/oxygen logging; complex lithologic log analysis; NMR T2 processing; dipole shear wave anisotropy logging; shear wave vertical seismic profile processing; structural mapping; and regional tectonic synthesis. Noteworthy technological successes for this reporting period include: (1) first (ever) high resolution, crosswell reflection images of SJV sediments; (2) first successful application of the TomoSeis acquisition system in siliceous shales; (3) first detailed reservoir characterization of SJV siliceous shales; (4) first mineral based saturation algorithm for SJV siliceous shales, and (5) first CO{sub 2} coreflood experiments for siliceous shale. Preliminary results from the CO{sub 2} coreflood experiments (2,500 psi) suggest that significant oil is being produced from the siliceous shale.

  19. Advanced reservoir characterization in the Antelope Shale to establish the viability of CO{sub 2} enhanced oil recovery in California`s Monterey Formation siliceous shales. Annual report, February 12, 1996--February 11, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Toronyi, R.M.

    1997-12-01

    The Buena Vista Hills field is located about 25 miles southwest of Bakersfield, in Kern County, California, about two miles north of the city of Taft, and five miles south of the Elk Hills field. The Antelope Shale zone was discovered at the Buena Vista Hills field in 1952, and has since been under primary production. Little research was done to improve the completion techniques during the development phase in the 1950s, so most of the wells are completed with about 1000 ft of slotted liner. The proposed pilot consists of four existing producers on 20 acre spacing with a new 10 acre infill well drilled as the pilot CO{sub 2} injector. Most of the reservoir characterization of the first phase of the project will be performed using data collected in the pilot pattern wells. This is the first annual report of the project. It covers the period February 12, 1996 to February 11, 1997. During this period the Chevron Murvale 653Z-26B well was drilled in Section 26-T31S/R23E in the Buena Vista Hills field, Kern County, California. The Monterey Formation equivalent Brown and Antelope Shales were continuously cored, the zone was logged with several different kinds of wireline logs, and the well was cased to a total depth of 4907 ft. Core recovery was 99.5%. Core analyses that have been performed include Dean Stark porosity, permeability and fluid saturations, field wettability, anelastic strain recovery, spectral core gamma, profile permeametry, and photographic imaging. Wireline log analysis includes mineral-based error minimization (ELAN), NMR T2 processing, and dipole shear wave anisotropy. A shear wave vertical seismic profile was acquired after casing was set and processing is nearly complete.

  20. Advanced reservoir characterization in the Antelope Shale to establish the viability of CO{sub 2} enhanced oil recovery in California`s Monterey Formation siliceous shales. Annual report, February 12, 1996--February 11, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Toronyi, R.M.

    1997-12-01

    The Buena Vista Hills field is located about 25 miles southwest of Bakersfield, in Kern County, California, about two miles north of the city of Taft, and five miles south of the Elk Hills field. The Antelope Shale zone was discovered at the Buena Vista Hills field in 1952, and has since been under primary production. Little research was done to improve the completion techniques during the development phase in the 1950s, so most of the wells are completed with about 1000 ft of slotted liner. The proposed pilot consists of four existing producers on 20 acre spacing with a new 10 acre infill well drilled as the pilot CO{sub 2} injector. Most of the reservoir characterization of the first phase of the project will be performed using data collected in the pilot pattern wells. This is the first annual report of the project. It covers the period February 12, 1996 to February 11, 1997. During this period the Chevron Murvale 653Z-26B well was drilled in Section 26-T31S/R23E in the Buena Vista Hills field, Kern County, California. The Monterey Formation equivalent Brown and Antelope Shales were continuously cored, the zone was logged with several different kinds of wireline logs, and the well was cased to a total depth of 4907 ft. Core recovery was 99.5%. Core analyses that have been performed include Dean Stark porosity, permeability and fluid saturations, field wettability, anelastic strain recovery, spectral core gamma, profile permeametry, and photographic imaging. Wireline log analysis includes mineral-based error minimization (ELAN), NMR T2 processing, and dipole shear wave anisotropy. A shear wave vertical seismic profile was acquired after casing was set and processing is nearly complete.

  1. Prediction of rocket plume radiative heating using backward Monte-Carlo method

    Science.gov (United States)

    Wang, K. C.

    1993-01-01

    A backward Monte-Carlo plume radiation code has been developed to predict rocket plume radiative heating to the rocket base region. This paper provides a description of this code and provides sample results. The code was used to predict radiative heating to various locations during test firings of 48-inch solid rocket motors at NASA Marshall Space Flight Center. Comparisons with test measurements are provided. Predictions of full scale sea level Redesigned Solid Rocket Motor (RSRM) and Advanced Solid Rocket Motor (ASRM) plume radiative heating to the Space Shuttle external tank (ET) dome center were also made. A comparison with the Development Flight Instrumentation (DFI) measurements is also provided.

  2. High Energy Density Additives for Hybrid Fuel Rockets to Improve Performance and Enhance Safety

    Science.gov (United States)

    Jaffe, Richard L.

    2014-01-01

    We propose a conceptual study of prototype strained hydrocarbon molecules as high energy density additives for hybrid rocket fuels to boost the performance of these rockets without compromising safety and reliability. Use of these additives could extend the range of applications for which hybrid rockets become an attractive alternative to conventional solid or liquid fuel rockets. The objectives of the study were to confirm and quantify the high enthalpy of these strained molecules and to assess improvement in rocket performance that would be expected if these additives were blended with conventional fuels. We confirmed the chemical properties (including enthalpy) of these additives. However, the predicted improvement in rocket performance was too small to make this a useful strategy for boosting hybrid rocket performance.

  3. North Antelope Highlands Wind Project

    Energy Technology Data Exchange (ETDEWEB)

    Pearlson, Matthew [Citizens Energy Corporation (CEC), Boston, MA (United States)

    2016-05-03

    This is the final report on the Wind Energy Development of 190 Mw on the Rosebud Indian Reservation in collaboration with Citizens Energy Corporation. The report discusses all pre-development activities since July of 2010 when award was granted. A systems impact study along with wind data accumulated over the past 5 years is contained in this report. We have responded to several RFPs concerning the sale of energy to certain offtakers, but we have failed to win a Power Purchase Agreement due to existing wind farms that won and the interconnection costs were already included in a previous PPAs, which we don't have that luxury. We continue this effort and hopefully in the near future we will win an RFP.

  4. Magnetic bearings: A key technology for advanced rocket engines?

    Science.gov (United States)

    Girault, J. PH.

    1992-01-01

    For several years, active magnetic bearings (AMB) have demonstrated their capabilities in many fields, from industrial compressors to control wheel suspension for spacecraft. Despite this broad area, no significant advance has been observed in rocket propulsion turbomachinery, where size, efficiency, and cost are crucial design criteria. To this respect, Societe Europeenne de Propulsion (SEP) had funded for several years significant efforts to delineate the advantages and drawbacks of AMB applied to rocket propulsion systems. Objectives of this work, relative technological basis, and improvements are described and illustrated by advanced turbopump layouts. Profiting from the advantages of compact design in cryogenic environments, the designs show considerable improvements in engine life, performances, and reliability. However, these conclusions should still be tempered by high recurrent costs, mainly due to the space-rated electronics. Development work focused on this point and evolution of electronics show the possibility to decrease production costs by an order of magnitude.

  5. Computational investigation on combustion instabilities in a rocket combustor

    Science.gov (United States)

    Yuan, Lei; Shen, Chibing

    2016-10-01

    High frequency combustion instability is viewed as the most challenging task in the development of Liquid Rocket Engines. In this article, results of attempts to capture the self-excited high frequency combustion instability in a rocket combustor are shown. The presence of combustion instability was demonstrated using point measurements, along with Fast Fourier Transform analysis and instantaneous flowfield contours. A baseline case demonstrates a similar wall heat flux profile as the associated experimental case. The acoustic oscillation modes and corresponding frequencies predicted by current simulations are almost the same as the results obtained from classic acoustic analysis. Pressure wave moving back and forth across the combustor was also observed. Then this baseline case was compared against different fuel-oxidizer velocity ratios. It predicts a general trend: the smaller velocity ratio produces larger oscillation amplitudes than the larger one. A possible explanation for the trend was given using the computational results.

  6. Identification of rocket-induced acoustic waves in the ionosphere

    Science.gov (United States)

    Mabie, Justin; Bullett, Terence; Moore, Prentiss; Vieira, Gerald

    2016-10-01

    Acoustic waves can create plasma disturbances in the ionosphere, but the number of observations is limited. Large-amplitude acoustic waves generated by energetic sources like large earthquakes and tsunamis are more readily observed than acoustic waves generated by weaker sources. New observations of plasma displacements caused by rocket-generated acoustic waves were made using the Vertically Incident Pulsed Ionospheric Radar (VIPIR), an advanced high-frequency radar. Rocket-induced acoustic waves which are characterized by low amplitudes relative to those induced by more energetic sources can be detected in the ionosphere using the phase data from fixed frequency radar observations of a plasma layer. This work is important for increasing the number and quality of observations of acoustic waves in the ionosphere and could help improve the understanding of energy transport from the lower atmosphere to the thermosphere.

  7. Feasibility and Performance of the Microwave Thermal Rocket Launcher

    Science.gov (United States)

    Parkin, Kevin L. G.; Culick, Fred E. C.

    2004-03-01

    Beamed-energy launch concepts employing a microwave thermal thruster are feasible in principle, and microwave sources of sufficient power to launch tons into LEO already exist. Microwave thermal thrusters operate on an analogous principle to nuclear thermal thrusters, which have experimentally demonstrated specific impulses exceeding 850 seconds. Assuming such performance, simple application of the rocket equation suggests that payload fractions of 10% are possible for a single stage to orbit (SSTO) microwave thermal rocket. We present an SSTO concept employing a scaled X-33 aeroshell. The flat aeroshell underside is covered by a thin-layer microwave absorbent heat-exchanger that forms part of the thruster. During ascent, the heat-exchanger faces the microwave beam. A simple ascent trajectory analysis incorporating X-33 aerodynamic data predicts a 10% payload fraction for a 1 ton craft of this type. In contrast, the Saturn V had 3 non-reusable stages and achieved a payload fraction of 4%.

  8. Materials Characterization of Additively Manufactured Components for Rocket Propulsion

    Science.gov (United States)

    Carter, Robert; Draper, Susan; Locci, Ivan; Lerch, Bradley; Ellis, David; Senick, Paul; Meyer, Michael; Free, James; Cooper, Ken; Jones, Zachary

    2015-01-01

    To advance Additive Manufacturing (AM) technologies for production of rocket propulsion components the NASA Glenn Research Center (GRC) is applying state of the art characterization techniques to interrogate microstructure and mechanical properties of AM materials and components at various steps in their processing. The materials being investigated for upper stage rocket engines include titanium, copper, and nickel alloys. Additive manufacturing processes include laser powder bed, electron beam powder bed, and electron beam wire fed processes. Various post build thermal treatments, including Hot Isostatic Pressure (HIP), have been studied to understand their influence on microstructure, mechanical properties, and build density. Micro-computed tomography, electron microscopy, and mechanical testing in relevant temperature environments has been performed to develop relationships between build quality, microstructure, and mechanical performance at temperature. A summary of GRC's Additive Manufacturing roles and experimental findings will be presented.

  9. Material Characterization of Additively Manufactured Components for Rocket Propulsion

    Science.gov (United States)

    Carter, Robert; Draper, Susan; Locci, Ivan; Lerch, Bradley; Ellis, David; Senick, Paul; Meyer, Michael; Free, James; Cooper, Ken; Jones, Zachary

    2015-01-01

    To advance Additive Manufacturing (AM) technologies for production of rocket propulsion components the NASA Glenn Research Center (GRC) is applying state of the art characterization techniques to interrogate microstructure and mechanical properties of AM materials and components at various steps in their processing. The materials being investigated for upper stage rocket engines include titanium, copper, and nickel alloys. Additive manufacturing processes include laser powder bed, electron beam powder bed, and electron beam wire fed processes. Various post build thermal treatments, including Hot Isostatic Pressure (HIP), have been studied to understand their influence on microstructure, mechanical properties, and build density. Micro-computed tomography, electron microscopy, and mechanical testing in relevant temperature environments has been performed to develop relationships between build quality, microstructure, and mechanical performance at temperature. A summary of GRCs Additive Manufacturing roles and experimental findings will be presented.

  10. Method of fabricating a rocket engine combustion chamber

    Science.gov (United States)

    Holmes, Richard R. (Inventor); Mckechnie, Timothy N. (Inventor); Power, Christopher A. (Inventor); Daniel, Ronald L., Jr. (Inventor); Saxelby, Robert M. (Inventor)

    1993-01-01

    A process for making a combustion chamber for a rocket engine wherein a copper alloy in particle form is injected into a stream of heated carrier gas in plasma form which is then projected onto the inner surface of a hollow metal jacket having the configuration of a rocket engine combustion chamber is described. The particles are in the plasma stream for a sufficient length of time to heat the particles to a temperature such that the particles will flatten and adhere to previously deposited particles but will not spatter or vaporize. After a layer is formed, cooling channels are cut in the layer, then the channels are filled with a temporary filler and another layer of particles is deposited.

  11. Scaling theory for liquid propellant rocket thrust chambers

    Directory of Open Access Journals (Sweden)

    C. M. Sethna

    1960-04-01

    Full Text Available With the advent of the very large liquid propellant rocket, it has become necessary, if possible, to derive a rational scaling theory for combustion chamber design so as to enable relatively simple and economical initial tests to be carried out on small scaled models using scaled parameters of propellant mass flows, pressure etc., and from these to predict operating and design data for the full scale rocket. Owing to the complex and interdependent nature of the aerothermo-chemical processes in the chamber involving evaporation, diffusion and chemical reaction, the similarity criteria must necessarily extend over several, non-dimensional parameters, but it is still possible to evolve relatively simple rules for correlating the design and performance of the model and large scale motors-as shown by Penner-Tsien and Crocco. The paper concludes with a discussion of the accuracy and practical feasibility of such scaling rules.

  12. Rocket injector anomalies study. Volume 2: Results of parametric studies

    Science.gov (United States)

    Przekwas, A. J.; Singhal, A. K.; Tam, L. T.

    1984-01-01

    The employment of a existing computer program to simulate three dimensional two phase gas spray flows in liquid propellant rocket engines. This was accomplished by modification of an existing three dimensional computer program (REFLAN3D) with Euler/Lagrange approach for simulating two phase spray flow, evaporation and combustion. The modified code is referred to as REFLAN3D-SPRAY. Computational studies of the model rocket engine combustion chamber are presented. The parametric studies of the two phase flow and combustion shows qualitatively correct response for variations in geometrical and physical parameters. The injection nonuniformity test with blocked central fuel injector holes shows significant changes in the central flame core and minor influence on the wall heat transfer fluxes.

  13. Characteristics of response factors of coaxial gaseous rocket injectors

    Science.gov (United States)

    Janardan, B. A.; Daniel, B. R.; Zinn, B. T.

    1975-01-01

    The results of an experimental investigation undertaken to determine the frequency dependence of the response factors of various gaseous propellant rocket injectors subject to axial instabilities are presented. The injector response factors were determined, using the modified impedance-tube technique, under cold-flow conditions simulating those observed in unstable rocket motors. The tested injectors included a gaseous-fuel injector element, a gaseous-oxidizer injector element and a coaxial injector with both fuel and oxidizer elements. Emphasis was given to the determination of the dependence of the injector response factor upon the open-area ratio of the injector, the length of the injector orifice, and the pressure drop across the injector orifices. The measured data are shown to be in reasonable agreement with the corresponding injector response factor data predicted by the Feiler and Heidmann model.

  14. Magnesium and Carbon Dioxide - A Rocket Propellant for Mars Missions

    Science.gov (United States)

    Shafirovich, E. IA.; Shiriaev, A. A.; Goldshleger, U. I.

    1993-01-01

    A rocket engine for Mars missions is proposed that could utilize CO2 accumulated from the Martian atmosphere as an oxidizer. For use as possible fuel, various metals, their hydrides, and mixtures with hydrogen compounds are considered. Thermodynamic calculations show that beryllium fuels ensure the most impulse but poor inflammability of Be and high toxicity of its compounds put obstacles to their applications. Analysis of the engine performance for other metals together with the parameters of ignition and combustion show that magnesium seems to be the most promising fuel. Ballistic estimates imply that a hopper with the chemical rocket engine on Mg + CO2 propellant could be readily developed. This vehicle would be able to carry out 2-3 ballistic flights on Mars before the final ascent to orbit.

  15. Standard Molded Composite Rocket Pyrogen Igniter - A progress report

    Science.gov (United States)

    Lucy, M. H.

    1978-01-01

    The pyrogen igniter has the function to furnish a controlled, high temperature, high pressure gas to ignite solid propellant surfaces in a rocket motor. Present pyrogens consist of numerous inert components. The Standard Molded Pyrogen Igniter (SMPI) consists of three basic parts, a cap with several integrally molded features, an ignition pellet retainer plate, and a tube with additional integrally molded features. A description is presented of an investigation which indicates that the SMPI concept is a viable approach to the design and manufacture of pyrogen igniters for solid propellant rocket motors. For some applications, combining the structural and thermal properties of molded composites can result in the manufacture of lighter assemblies at considerable cost reduction. It is demonstrated that high strength, thin walled tubes with high length to diameter ratios can be fabricated from reinforced plastic molding compound using the displacement compression process.

  16. Developing Avionics Hardware and Software for Rocket Engine Testing

    Science.gov (United States)

    Aberg, Bryce Robert

    2014-01-01

    My summer was spent working as an intern at Kennedy Space Center in the Propulsion Avionics Branch of the NASA Engineering Directorate Avionics Division. The work that I was involved with was part of Rocket University's Project Neo, a small scale liquid rocket engine test bed. I began by learning about the layout of Neo in order to more fully understand what was required of me. I then developed software in LabView to gather and scale data from two flowmeters and integrated that code into the main control software. Next, I developed more LabView code to control an igniter circuit and integrated that into the main software, as well. Throughout the internship, I performed work that mechanics and technicians would do in order to maintain and assemble the engine.

  17. The Water Recovery X-ray Rocket (WRX-R)

    Science.gov (United States)

    Miles, Drew

    2017-08-01

    The Water Recovery X-ray Rocket (WRX-R) is a diffuse soft X-ray spectrometer that will launch on a sounding rocket from the Kwajalein Atoll. WRX-R has a field of view of >10 deg2 and will observe the Vela supernova remnant. A mechanical collimator, state-of-the-art off-plane reflection grating array and hybrid CMOS detector will allow WRX to achieve the most highly-resolved spectrum of the Vela SNR ever recorded. In addition, this payload will fly a hard X-ray telescope that is offset from the soft X-ray spectrometer in order to observe the pulsar at the center of the remnant. We present here an introduction to the instrument, the expected science return, and an update on the state of the payload as we work towards launch.

  18. Reusable, flyback liquid rocket booster for the Space Shuttle

    Science.gov (United States)

    Benton, Mark G.

    1989-08-01

    This paper outlines a preliminary design for an unmanned, reusable, flyback liquid rocket booster (LRB) as an evolutionary follow-on to the Shuttle solid rocket booster (SRB). Previous Shuttle liquid-propellant booster concepts are reviewed in order to gain insight into these designs. The operating costs, environmental impacts, and abort options of the SRB are discussed. The LRB flight profile and advantages of LRB use are discussed. The preliminary design for the LRB is outlined in detail using calculations and drawings. This design maximizes the use of existing hardware and proven technology to minimize cost and development time. The LRB design is presented as a more capable, more environmentally acceptable, and safer Shuttle booster.

  19. Study on risk measurement about ammunition-rocket system

    Institute of Scientific and Technical Information of China (English)

    Gu Xiaohui; Zhao Youshou

    2005-01-01

    Modern ammunition-rocket system is a complicated multidisciplinary system. During its development,undetermined factors will bring many risks. This paper elaborates the importance of risk analysis approach to ammunition-rocket system development and analyses various methods of risk analysis and estimation. Combined with practical situation of weapon system development, the risk measurement function with characteristics of risk preference is given provided that the risk preference characteristic of behavior maker is risk neutral of fixed constant. The development risk analysis based on risk measurement function enables effective risk decision to be made on the basis of quantified risk.Taking anti-helicopter intelligent mine warhead as an example, the paper verifies the efficiency of the method and shows that it has a scientific and practical value.

  20. Addendum to the Closure Report for Corrective Action Unit 484: Surface Debris, Waste Sites, and Burn Area, Tonopah Test Range, Nevada (Revision 0)

    Energy Technology Data Exchange (ETDEWEB)

    Mark Burmeister

    2011-03-01

    Corrective Action Unit (CAU) 484 Streamlined Approach for Environmental Restoration (SAFER) activities called for the identification and remediation of surface hot spot depleted uranium (DU) with some excavation to determine the vertical extent of contamination (NNSA/NSO, 2004). During the CAU 484 SAFER investigation (conducted November 2003 through August 2007), approximately 50 locations containing DU were identified on Antelope Lake. All but four locations (CA-1, SA-5-9, SA-12-15, and SA-4) were remediated. Figure 1-1 shows locations of the four use restriction (UR) sites. The four locations were determined to have failed the SAFER conceptual site model assumption of a small volume hot spot. Two of the locations (CA-1 and SA-5-9) were excavated to depths of 3.5 to 7 feet (ft) below ground surface (bgs), and a third location (SA-12-15) with a footprint of 30 by 60 ft was excavated to a depth of 0.5 ft. At the fourth site (SA-4), the discovery of unexploded ordnance (UXO) halted the excavation due to potential safety concerns. Remediation activities on Antelope Lake resulted in the removal of approximately 246 cubic yards (yd3) of DU-impacted soil from the four UR sites; however, Kiwi surveys confirmed that residual DU contamination remained at each of the four sites. (The Kiwi was a Remote Sensing Laboratory [RSL] vehicle equipped with a data-acquisition system and four sodium iodide gamma detectors. Surveys were conducted with the vehicle moving at a rate of approximately 10 miles per hour with the gamma detectors positioned 14 to 28 inches [in.] above the ground surface [NNSA/NSO, 2004]).

  1. Data Mining for ISHM of Liquid Rocket Propulsion Status Update

    Science.gov (United States)

    Srivastava, Ashok; Schwabacher, Mark; Oza, Nijunj; Martin, Rodney; Watson, Richard; Matthews, Bryan

    2006-01-01

    This document consists of presentation slides that review the current status of data mining to support the work with the Integrated Systems Health Management (ISHM) for the systems associated with Liquid Rocket Propulsion. The aim of this project is to have test stand data from Rocketdyne to design algorithms that will aid in the early detection of impending failures during operation. These methods will be extended and improved for future platforms (i.e., CEV/CLV).

  2. Oxidation of Copper Alloy Candidates for Rocket Engine Applications

    Science.gov (United States)

    Ogbuji, Linus U. Thomas; Humphrey, Donald L.

    2002-01-01

    The gateway to affordable and reliable space transportation in the near future remains long-lived rocket-based propulsion systems; and because of their high conductivities, copper alloys remain the best materials for lining rocket engines and dissipating their enormous thermal loads. However, Cu and its alloys are prone to oxidative degradation -- especially via the ratcheting phenomenon of blanching, which occurs in situations where the local ambient can oscillate between oxidation and reduction, as it does in a H2/02- fuelled rocket engine. Accordingly, resistance to blanching degradation is one of the key requirements for the next generation of reusable launch vehicle (RLV) liner materials. Candidate copper alloys have been studied with a view to comparing their oxidation behavior, and hence resistance to blanching, in ambients corresponding to conditions expected in rocket engine service. These candidate materials include GRCop-84 and GRCop-42 (Cu - Cr-8 - Nb-4 and Cu - Cr-4 - Nb-2 respectively); NARloy-Z (Cu-3%Ag-0.5%Y), and GlidCop (Cu-O.l5%Al2O3 ODS alloy); they represent different approaches to improving the mechanical properties of Cu without incurring a large drop in thermal conductivity. Pure Cu (OFHC-Cu) was included in the study to provide a baseline for comparison. The samples were exposed for 10 hours in the TGA to oxygen partial pressures ranging from 322 ppm to 1.0 atmosphere and at temperatures of up to 700 C, and examined by SEM-EDS and other techniques of metallography. This paper will summarize the results obtained.

  3. Optimisation Study of a Homogeneously-Catalysed HTP Rocket Engine

    Science.gov (United States)

    Musker, A.; Roberts, G.; Chandler, P.; Grayson, J.; Holdsworth, J.

    2004-10-01

    The decomposition of hydrogen peroxide (HTP) using a liquid catalyst offers an alternative to the employment of traditional catalyst packs. A test rig has been used to estimate the length of chamber required for complete decomposition to take place for the case of HTP with a phosphorus content some 10000 times the level normally associated with rocket-grade HTP. Complete decomposition within a 10 mm advection length was achieved.

  4. Vacuum plasma spray applications on liquid fuel rocket engines

    Science.gov (United States)

    Mckechnie, T. N.; Zimmerman, F. R.; Bryant, M. A.

    1992-01-01

    The vacuum plasma spray process (VPS) has been developed by NASA and Rocketdyne for a variety of applications on liquid fuel rocket engines, including the Space Shuttle Main Engine. These applications encompass thermal barrier coatings which are thermal shock resistant for turbopump blades and nozzles; bond coatings for cryogenic titanium components; wear resistant coatings and materials; high conductivity copper, NaRloy-Z, combustion chamber liners, and structural nickel base material, Inconel 718, for nozzle and combustion chamber support jackets.

  5. Storable Hypergolic Solid Fuel for Hybrid Rocket Engines

    Directory of Open Access Journals (Sweden)

    R. V. Singh

    1976-07-01

    Full Text Available A solid fuel was synthesised by condensing aniline with furfuraldehyde. The product was directly cast in the rocket motor casing. After curing a hard solid mass was obtained. This was found to have good hypergolicity with RFNA (Red Fuming Nitric Acid, good storability at room temperature and the mechanical properties. The paper presented the techniques of casting, ignition delay measurements and indicates the future programme for this study.

  6. Approaches to Low Fuel Regression Rate in Hybrid Rocket Engines

    OpenAIRE

    Dario Pastrone

    2012-01-01

    Hybrid rocket engines are promising propulsion systems which present appealing features such as safety, low cost, and environmental friendliness. On the other hand, certain issues hamper the development hoped for. The present paper discusses approaches addressing improvements to one of the most important among these issues: low fuel regression rate. To highlight the consequence of such an issue and to better understand the concepts proposed, fundamentals are summarized. Two approaches are pre...

  7. Design of a hybrid rocket / inflatable wing UAV

    Science.gov (United States)

    Sudduth, Cory

    This paper discusses the design challenges and development of a UAV that transitions from a rocket, which allows the aircraft to reach a target altitude rapidly, and then deploys an inflatable wing from an enclosed shell in midflight to allow for loitering and surveillance. The wing deployment and transition is tested in static and dynamic environments, while the performance and stability of both the aircraft mode and rocket mode are examined analytically. An in-depth discussion of key components, including the design, analysis and testing, is also included. Designing an UAV that transitions from a high velocity rocket, to a slow velocity UAV provides many difficult and unique design challenges. For example, the incorporation of deployable wing technology into a full UAV system results in many design constraints. In this particular design inflatable wings are used to generate lift during aircraft mode, and the stabilizing fins for the main wing also acted as the fins for the vehicle during its rocket phase. This required the balancing of the two different vehicle configurations to ensure that the aircraft would be able to fly stably in both modes, and transition between them without catastrophic failure. Significant research, and testing went into the finding the best method of storing the inflatable wing, as well as finding the required inflation rate to minimize unsteady aerodynamic affects. Design work was also invested in the development of an inflation system, as it had to be highly reliable, and yet very light weight for use in this small UAV. This paper discusses how these design challenges were overcome, the development and testing of individual sub-components and how they are incorporated into the overall vehicle. The analysis that went into this UAV, as well as methods used to optimize the design in order to minimize weight and maximize the aircraft performance and loitering time is also discussed.

  8. Sounding rocket observations of particle data in the cusp

    Science.gov (United States)

    Mella, M.; Lynch, K.; Kintner, P.; Lundberg, E.; Lessard, M.

    2008-12-01

    The winter 2008 Scifer-2 sounding rocket campaign studied ionospheric outflow in the cusp region. The rocket was launched on January 18, 2008 at 0730 UT from the Andoya Rocket Range in Norway, reaching an apogee of 1468 km over the Eiscat Svalbard Radar. The Scifer 2 campaign was designed as a joint case study, involving both ground and in situ observations, of the low altitude signatures of ionospheric outflow. In situ observations show a thermal ion population with temperatures around 0.6 - 0.8 eV, while ESR observes the temperature at lower altitudes to be ~0.2 eV. This difference is a result of calculating the average over all in situ look directions, which would artificially raise the temperature. In addition to the thermal ion population, there are several bursts of a hotter population of ions with temperatures ranging between 12 -20 eV, along with concurrent elevated wave activity. These hotter ions appear to have been accelerated to energies of several hundred eV, and show interesting velocity dispersion signatures with repeated bands at increasing energies. These two populations are not observed simultaneously, but rather are localized in different regions bordering one another. Additionally, the pitch angle distributions for each of these populations are different. Similar signatures have been seen by other nightside low altitude sounding rockets where upgoing low energy ions are seen adjacent to and coincident with higher energy ion precipitation. Neither observed ion population has a clear local relationship to the variations in the ambient electron temperature, which is a tracer for soft precipitation. We will continue to explore these populations and their boundaries as a case study of structuring in particle signatures in the cusp.

  9. Nuclear Thermal Rocket by 2000: a DOE Perspective

    Science.gov (United States)

    Howe, Steven D.; Stanley, Marland

    1992-01-01

    It is asserted that a Nuclear Propulsion Space Transportation System is required for the Manned Mars Mission. Additionally, it is felt that a Nuclear Propulsion Space Transportation System can support a wide variety of future space missions, including lunar base implementation and support. The Rover/NERVA program demonstrated that a safe, reliable Nuclear Thermal Rocket (NTR) can be developed and operated for sufficient run times, at desirable temperatures, and with multiple restarts. The discussion is presented in viewgraph form.

  10. NERVA-Derived Concept for a Bimodal Nuclear Thermal Rocket

    Science.gov (United States)

    Fusselman, Steven P.; Borowski, Stanley K.; Frye, Patrick E.; Gunn, Stanley V.; Morrison, Calvin Q.

    2005-02-01

    The Nuclear Thermal Rocket is an enabling technology for human exploration missions. The "bimodal" NTR (BNTR) provides a novel approach to meeting both propulsion and power requirements of future manned and robotic missions. The purpose of this study was to evaluate tie-tube cooling configurations, NTR performance, Brayton cycle performance, and LOX-Augmented NTR (LANTR) feasibility to arrive at a point of departure BNTR configuration for subsequent system definition.

  11. Method of injecting fluid propellants into a rocket combustion chamber

    Science.gov (United States)

    Schneider, Steven J. (Inventor)

    1991-01-01

    A rocket injector is provided with multiple sets of manifolds for supplying propellants to injector elements. Sensors transmit the temperatures of the propellants to a suitable controller which is operably connected to valves between these manifolds and propellant storage tanks. Additional valves are opened to furnish propellants to more of the manifolds when cryogenic propellant temperatures are sensed. Only a portion of the valves are opened to furnish propellants to some of the manifolds when lower temperatures are sensed.

  12. Comparison of HRDI wind measurements with radar and rocket observations

    Energy Technology Data Exchange (ETDEWEB)

    Burrage, M.D.; Skinner, W.R.; Marshall, A.R.; Hays, P.B.; Lieberman, R.S.; Gell, D.A.; Ortland, D.A.; Morton, Y.T.; Wu, D.L.; Franke, S.J.; Schmidlin, F.J.; Vincent, R.A.

    1993-06-18

    This paper reports wind measurements in the mesosphere and lower thermosphere made by the high resolution doppler imager (HRDI) on board the upper atmosphere research satellite (UARS). These measurements are correlated with ground based radar and rocket measurements. The HRDI makes measurements by observing doppler shifts in molecular oxygen lines. The intercomparison helps to validate the remote sensing results, helps to verify the on board calibration system, and also gives a common measurement which other measurements systems can be compared against.

  13. Rhinoconjunctivitis and occupational asthma caused by Diplotaxis erucoides (wall rocket).

    Science.gov (United States)

    Brito, F F; Mur, P; Bartolomé, B; Galindo, P A; Gómez, E; Borja, J; Martínez, A

    2001-07-01

    Wall rocket (Diplotaxis erucoides) is a common Crucifera plant that grows in European and American vineyards and olive groves. We present the cases of 2 farmers with rhinoconjunctivitis and asthma related to wine-growing tasks during D erucoides pollination (March-April). The aim of this work was to demonstrate that occupational symptoms were caused by D erucoides pollen sensitization. Cutaneous tests, specific IgE measurements, conjunctival and bronchial provocation tests, and peak-flow measurements during working days were performed.

  14. SMC Standard: Evaluation and Test Requirements for Liquid Rocket Engines

    Science.gov (United States)

    2017-07-26

    Company, 2002. 23. NASA SP-8123, Liquid Rocket Lines, Bellows, Flexible Hoses, and Filters, National Aeronautics and Space Administration, April 1977...boundaries established by design requirements. For example, the test screens for malfunctions, failure to execute, sequence of action, interruption...Test: A static load or pressure test performed as an acceptance workmanship screen to prove the structural integrity of a unit or assembly. Gives

  15. Study of Cavitation/Vaporization in Liquid Rocket Thruster Injectors

    Science.gov (United States)

    2011-07-29

    Caveny, L. H., and Summerfield, M., Aluminized Solid Propellants Burning in a Rocket Motor Flowfield, AIAA Journal, Vol. 16, No. 7, 1978, pp. 736-739. [2...the swirl chamber, and the pulsator and manifold are made of 304 stainless steel . Figure 1: Nomenclature defined for swirl injector. Table 1...Wayne, NJ, 2009 [17] MATLAB, Matrix Laboratory, Software Package, R2009a, The MathWorks, Natick, MA, 2009. [18] Coleman, H.W. and Steele , W.G

  16. Optical Signature Analysis of Tumbling Rocket Bodies via Laboratory Measurements

    Science.gov (United States)

    Cowardin, H.; Lederer, S.; Liou, J.-C.

    2012-01-01

    The NASA Orbital Debris Program Office has acquired telescopic lightcurve data on massive intact objects, specifically spent rocket bodies, in order to ascertain tumble rates in support of the Active Debris Removal (ADR) task to help remediate the LEO environment. Rotation rates are needed to plan and develop proximity operations for potential future ADR operations. To better characterize and model optical data acquired from ground-based telescopes, the Optical Measurements Center (OMC) at NASA/JSC emulates illumination conditions in space using equipment and techniques that parallel telescopic observations and source-target-sensor orientations. The OMC employs a 75-watt Xenon arc lamp as a solar simulator, an SBIG CCD camera with standard Johnson/Bessel filters, and a robotic arm to simulate an object's position and rotation. The light source is mounted on a rotary arm, allowing access any phase angle between 0 -- 360 degrees. The OMC does not attempt to replicate the rotation rates, but focuses on how an object is rotating as seen from multiple phase angles. The two targets studied are scaled (1:48), SL-8 Cosmos 3M second stages. The first target is painted in the standard government "gray" scheme and the second target is primary white, as used for commercial missions. This paper summarizes results of the two scaled rocket bodies, each rotated about two primary axes: (a) a spin-stabilized rotation and (b) an end-over-end rotation. The two rotation states are being investigated as a basis for possible spin states of rocket bodies, beginning with simple spin states about the two primary axes. The data will be used to create a database of potential spin states for future works to convolve with more complex spin states. The optical signatures will be presented for specific phase angles for each rocket body and shown in conjunction with acquired optical data from multiple telescope sources.

  17. A Historical Systems Study of Liquid Rocket Engine Throttling Capabilities

    Science.gov (United States)

    Betts, Erin M.; Frederick, Robert A., Jr.

    2010-01-01

    This is a comprehensive systems study to examine and evaluate throttling capabilities of liquid rocket engines. The focus of this study is on engine components, and how the interactions of these components are considered for throttling applications. First, an assessment of space mission requirements is performed to determine what applications require engine throttling. A background on liquid rocket engine throttling is provided, along with the basic equations that are used to predict performance. Three engines are discussed that have successfully demonstrated throttling. Next, the engine system is broken down into components to discuss special considerations that need to be made for engine throttling. This study focuses on liquid rocket engines that have demonstrated operational capability on American space launch vehicles, starting with the Apollo vehicle engines and ending with current technology demonstrations. Both deep throttling and shallow throttling engines are discussed. Boost and sustainer engines have demonstrated throttling from 17% to 100% thrust, while upper stage and lunar lander engines have demonstrated throttling in excess of 10% to 100% thrust. The key difficulty in throttling liquid rocket engines is maintaining an adequate pressure drop across the injector, which is necessary to provide propellant atomization and mixing. For the combustion chamber, cooling can be an issue at low thrust levels. For turbomachinery, the primary considerations are to avoid cavitation, stall, surge, and to consider bearing leakage flows, rotordynamics, and structural dynamics. For valves, it is necessary to design valves and actuators that can achieve accurate flow control at all thrust levels. It is also important to assess the amount of nozzle flow separation that can be tolerated at low thrust levels for ground testing.

  18. 青藏公路沿线白昼交通运输等人类活动对藏羚羊迁徙的影响%Effects of traffic during daytime and other human activities on the migration of Tibetan Antelope along the Qinghai-Tibet high-way, Qinghai-Tibet Plateau

    Institute of Scientific and Technical Information of China (English)

    裘丽; 冯祚建

    2004-01-01

    To study effects of traffic during daytime and other human activities, we conducted surveys on the migration of Tibetan antelope Pantholops hodgsoni along the Qinghai-Tibet highway between Kunlun Mountain Pass to Wudaoliang,using line transects (LT) from June to September in 2001 and 2002, Data were collected for 64 days with 17 days in 2001, and 47days in 2002. The Stationary Observation Method (SOM) was also adopted for the investigation of status of the disturbance from traffic when antelopes passing the highway and the traffic situation from August 6 to 28 (6 : 30-19: 00), 4 to 20 (6: 00- 18: 00) and from December 21 to 29 (9:00- 19: 00) in 2002. The results showed that,the period of migration in 2002 was more prolonged than in 2001, and it took at least 45 min for each group to cross the highway, with success ratio of only 30.2 %, and the traffic flow of summer daytime was 76/h, while the winter's traffic flow was 29/h. Highway and rail traffic should be managed during daylight hours from June to August, to allow for the migration of the antelopes. Also conservation education and a further survey should be emphasized for the protection on the species [Acta Zoologica Sinica 50 (4) : 669-674, 2004].

  19. [REAL AND UNREAL BACKLASHES OF AEROSPACE ACTIVITY FOR THE HEALTH OF POPULATION RESIDING NEAR AREAS OF FALL OF BEING SEPARATED PARTS OF CARRIER ROCKETS].

    Science.gov (United States)

    Meshkov, N A; Valtseva, E A; Kharlamova, E N; Kulikova, A Z

    2015-01-01

    Since the late 1990s, the ongoing debate about the consequences of the rocket-space activities for the health of people residing near areas offall ofseparatingfrom parts of rockets. Some scientists (Kolyado IB et al., 2001, 2013; Shoikhet YN et al., 2005, 2008; Skrebtsova NV 2005, 2006, Sidorov PI et al., 2007) argue that the main cause of morbidity is the effect of unsymmetrical dimethyl hydrazine (UDMH). However, environmentalists find it only in areas offalling fragments of separated parts of carrier rockets. Presented in the article data were obtained as a result of perennial epidemiological and hygienic research. There was performed a hygienic assessment of the content of chemical substances in water soil andfood, nutritional status and health risk near areas of the district of falling 310 and 326. There were studied conditions of work and the health of military personnel at the sites of storage of propellant components. The relationship between revealed diseases and UDMH was not established, but there was their causality due to the influence of environmental factors characteristic of territories and living conditions. In the settlements near the area of falling district 310 the share of extremely anxious persons was shown to be 1.8 times higher than in controls, which is caused by cases of falling fragments stages of carrier rockets in the territory of settlements.

  20. Wind Tunnel Tests on Aerodynamic Characteristics of Advanced Solid Rocket

    Science.gov (United States)

    Kitamura, Keiichi; Fujimoto, Keiichiro; Nonaka, Satoshi; Irikado, Tomoko; Fukuzoe, Moriyasu; Shima, Eiji

    The Advanced Solid Rocket is being developed by JAXA (Japan Aerospace Exploration Agency). Since its configuration has been changed very recently, its aerodynamic characteristics are of great interest of the JAXA Advanced Solid Rocket Team. In this study, we carried out wind tunnel tests on the aerodynamic characteristics of the present configuration for Mach 1.5. Six test cases were conducted with different body configurations, attack angles, and roll angles. A six component balance, oilflow visualization, Schlieren images were used throughout the experiments. It was found that, at zero angle-of-attack, the flow around the body were perturbed and its drag (axial force) characteristics were significantly influenced by protruding body components such as flanges, cable ducts, and attitude control units of SMSJ (Solid Motor Side Jet), while the nozzle had a minor role. With angle-of-attack of five degree, normal force of CNα = 3.50±0.03 was measured along with complex flow features observed in the full-component model; whereas no crossflow separations were induced around the no-protuberance model with CNα = 2.58±0.10. These values were almost constant with respect to the angle-of-attack in both of the cases. Furthermore, presence of roll angle made the flow more complicated, involving interactions of separation vortices. These data provide us with fundamental and important aerodynamic insights of the Advanced Solid Rocket, and they will be utilized as reference data for the corresponding numerical analysis.

  1. Ultra-fast Escape of a Octopus-inspired Rocket

    Science.gov (United States)

    Weymouth, Gabriel; Triantafyllou, Michael

    2013-11-01

    The octopus, squid, and other cephalopods inflate with water and then release a jet to accelerate in the opposite direction. This escape mechanism is particularly interesting in the octopus because they become initially quite bluff, yet this does not hinder them in achieving impressive bursts of speed. We examine this somewhat paradoxical maneuver using a simple deflating spheroid model in both potential and viscous flow. We demonstrate that the dynamic reduction of the width of the body completely changes the flow and forces acting on the escaping rocket in three ways. First, a body which reduces in size can generate an added mass thrust which counteracts the added mass inertia. Second, the motion of the shrinking wall acts similar to suction on a static wall, reducing separation and drag forces in a viscous fluid, but that this effects depends on the rate of size change. Third, using a combination of these two features it is possible to initially load the fluid with kinetic energy when heavy and bluff and then recover that energy when streamlined and light, enabling ultra-fast accelerations. As a notable example, these mechanisms allow a shrinking spheroid rocket in a heavy inviscid fluid to achieve speeds greater than an identical rocket in the vacuum of space. Southampton Marine and Maritime Institute.

  2. Dual-fuel, dual-mode rocket engine

    Science.gov (United States)

    Martin, James A. (Inventor)

    1989-01-01

    The invention relates to a dual fuel, dual mode rocket engine designed to improve the performance of earth-to-orbit vehicles. For any vehicle that operates from the earth's surface to earth orbit, it is advantageous to use two different fuels during its ascent. A high density impulse fuel, such as kerosene, is most efficient during the first half of the trajectory. A high specific impulse fuel, such as hydrogen, is most efficient during the second half of the trajectory. The invention allows both fuels to be used with a single rocket engine. It does so by adding a minimum number of state-of-the-art components to baseline single made rocket engines, and is therefore relatively easy to develop for near term applications. The novelty of this invention resides in the mixing of fuels before exhaust nozzle cooling. This allows all of the engine fuel to cool the exhaust nozzle, and allows the ratio of fuels used throughout the flight depend solely on performance requirements, not cooling requirements.

  3. Application of Chaboche Model in Rocket Thrust Chamber Analysis

    Science.gov (United States)

    Asraff, Ahmedul Kabir; Suresh Babu, Sheela; Babu, Aneena; Eapen, Reeba

    2017-06-01

    Liquid Propellant Rocket Engines are commonly used in space technology. Thrust chamber is one of the most important subsystems of a rocket engine. The thrust chamber generates propulsive thrust force for flight of the rocket by ejection of combustion products at supersonic speeds. Often double walled construction is employed for these chambers. The thrust chamber investigated here has its hot inner wall fabricated out of a high thermal conductive material like copper alloy and outer wall made of stainless steel. Inner wall is subjected to high thermal and pressure loads during operation of engine due to which it will be in the plastic regime. Main reasons for the failure of such chambers are fatigue in the plastic range (called as low cycle fatigue since the number of cycles to failure will be low in plastic range), creep and thermal ratcheting. Elasto plastic material models are required to simulate the above effects through a cyclic stress analysis. This paper gives the details of cyclic stress analysis carried out for the thrust chamber using different plasticity model combinations available in ANSYS (Version 15) FE code. The best model among the above is applied in the cyclic stress analysis of two dimensional (plane strain and axisymmetric) and three dimensional finite element models of thrust chamber. Cyclic life of the chamber is calculated from stress-strain graph obtained from above analyses.

  4. Priming and physiological performance of rocket salad seeds

    Directory of Open Access Journals (Sweden)

    Jarbas Alves

    2012-03-01

    Full Text Available Rocket salad is a leafy vegetable that has become a popular food in various regions of Brazil. Its multiplication is only possible with seeds and, therefore, high quality propagation material is necessary for establishing a good crop. Studies show that seed conditioning promotes physiological improvements in the speed and uniformity of seedling establishment in the field. The present work was carried out in order to verify the effect of priming on the performance of rocket salad seeds. Five seed lots of rocket salad, cultivar Cultivada, were primed for 24 hours, using the potentials of 0.0, -0.1, -0.2, -0.3MPa, in a polyethylene glycol (Carbonax 6000 solution. A completely randomized design with 20 treatments (5 seed lots × 4 potentials was used, with four replications. Means were compared by Tukey’s test and regression analyses were conducted for the osmotic potential. The data showed that priming improved germination and the percentage of strong plants in relation to vigor.

  5. Development of the Hawk/Nike Hawk sounding rocket vehicles

    Science.gov (United States)

    Flowers, B. J.

    1976-01-01

    A new sounding rocket family, the Hawk and Nike-Hawk Vehicles, have been developed, flight tested and added to the NASA Sounding Rocket Vehicle Stable. The Hawk is a single-stage vehicle that will carry 35.6 cm diameter payloads weighing 45.5 kg to 91 kg to altitudes of 78 km to 56 km, respectively. The two-stage Nike-Hawk will carry payloads weighing 68 kg to 136 kg to altitudes of 118 km to 113 km, respectively. Both vehicles utilize the XM22E8 Hawk rocket motor which is available in large numbers as a surplus item from the U.S. Army. The Hawk fin and tail can hardware were designed in-house. The Nike tail can and fin hardware are surplus Nike-Ajax booster hardware. Development objectives were to provide a vehicle family with a larger diameter, larger volume payload capability than the Nike-Apache and Nike-Tomahawk vehicles at comparable cost. Both vehicles performed nominally in flight tests.

  6. The FOXSI sounding rocket: Latest analysis and results

    Science.gov (United States)

    Camilo Buitrago-Casas, Juan; Glesener, Lindsay; Christe, Steven; Krucker, Sam; Ishikawa, Shin-Nosuke; Takahashi, Tadayuki; Ramsey, Brian; Han, Raymond

    2016-05-01

    Hard X-ray (HXR) observations are a linchpin for studying particle acceleration and hot thermal plasma emission in the solar corona. Current and past indirectly imaging instruments lack the sensitivity and dynamic range needed to observe faint HXR signatures, especially in the presences of brighter sources. These limitations are overcome by using HXR direct focusing optics coupled with semiconductor detectors. The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket experiment is a state of the art solar telescope that develops and applies these capabilities.The FOXSI sounding rocket has successfully flown twice, observing active regions, microflares, and areas of the quiet-Sun. Thanks to its far superior imaging dynamic range, FOXSI performs cleaner hard X-ray imaging spectroscopy than previous instruments that use indirect imaging methods like RHESSI.We present a description of the FOXSI rocket payload, paying attention to the optics and semiconductor detectors calibrations, as well as the upgrades made for the second flight. We also introduce some of the latest FOXSI data analysis, including imaging spectroscopy of microflares and active regions observed during the two flights, and the differential emission measure distribution of the nonflaring corona.

  7. Cycle Trades for Nuclear Thermal Rocket Propulsion Systems

    Science.gov (United States)

    White, C.; Guidos, M.; Greene, W.

    2003-01-01

    Nuclear fission has been used as a reliable source for utility power in the United States for decades. Even in the 1940's, long before the United States had a viable space program, the theoretical benefits of nuclear power as applied to space travel were being explored. These benefits include long-life operation and high performance, particularly in the form of vehicle power density, enabling longer-lasting space missions. The configurations for nuclear rocket systems and chemical rocket systems are similar except that a nuclear rocket utilizes a fission reactor as its heat source. This thermal energy can be utilized directly to heat propellants that are then accelerated through a nozzle to generate thrust or it can be used as part of an electricity generation system. The former approach is Nuclear Thermal Propulsion (NTP) and the latter is Nuclear Electric Propulsion (NEP), which is then used to power thruster technologies such as ion thrusters. This paper will explore a number of indirect-NTP engine cycle configurations using assumed performance constraints and requirements, discuss the advantages and disadvantages of each cycle configuration, and present preliminary performance and size results. This paper is intended to lay the groundwork for future efforts in the development of a practical NTP system or a combined NTP/NEP hybrid system.

  8. Nuclear Thermal Rocket - An Established Space Propulsion Technology

    Science.gov (United States)

    Klein, Milton

    2004-02-01

    From the late 1950s to the early 1970s a major program successfully developed the capability to conduct space exploration using the advanced technology of nuclear rocket propulsion. The program had two primary elements: pioneering and advanced technology work-Rover-at Los Alamos National Laboratory and its contractors provided the basic reactor design, fuel materials development, and reactor testing capability; and engine development-NERVA-by the industrial team of Aerojet and Westinghouse building on and extending the Los Alamos efforts to flight system development. This presentation describes the NERVA program, the engine system testing that demonstrated the space-practical operation capabilities of nuclear thermal rockets, and the mission studies that point the way to most effectively use the NTR capabilities. Together, the two programs established a technology base that includes proven NTR capabilities of (1) over twice the specific impulse of chemical propulsion systems, (2) thrust capabilities ranging from 44kN to 1112kN, and (3) practical thrust-to-weight ratios for future NASA space exploration missions, both manned payloads to Mars and unmanned payloads to the outer planets. The overall nuclear rocket program had a unique management structure that integrated the efforts of the two government agencies involved-NASA and the then-existing Atomic Energy Commission. The objective of this paper is to summarize and convey the technical and management lessons learned in this program as the nation considers the design of its future space exploration activities.

  9. Nuclear rockets: High-performance propulsion for Mars

    Science.gov (United States)

    Watson, C. W.

    1994-05-01

    A new impetus to manned Mars exploration was introduced by President Bush in his Space Exploration Initiative. This has led, in turn, to a renewed interest in high-thrust nuclear thermal rocket propulsion (NTP). The purpose of this report is to give a brief tutorial introduction to NTP and provide a basic understanding of some of the technical issues in the realization of an operational NTP engine. Fundamental physical principles are outlined from which a variety of qualitative advantages of NTP over chemical propulsion systems derive, and quantitative performance comparisons are presented for illustrative Mars missions. Key technologies are described for a representative solid-core heat-exchanger class of engine, based on the extensive development work in the Rover and NERVA nuclear rocket programs (1955 to 1973). The most driving technology, fuel development, is discussed in some detail for these systems. Essential highlights are presented for the 19 full-scale reactor and engine tests performed in these programs. On the basis of these tests, the practicality of graphite-based nuclear rocket engines was established. Finally, several higher-performance advanced concepts are discussed. These have received considerable attention, but have not, as yet, developed enough credibility to receive large-scale development.

  10. Development of the Hawk/Nike Hawk sounding rocket vehicles

    Science.gov (United States)

    Flowers, B. J.

    1976-01-01

    A new sounding rocket family, the Hawk and Nike-Hawk Vehicles, have been developed, flight tested and added to the NASA Sounding Rocket Vehicle Stable. The Hawk is a single-stage vehicle that will carry 35.6 cm diameter payloads weighing 45.5 kg to 91 kg to altitudes of 78 km to 56 km, respectively. The two-stage Nike-Hawk will carry payloads weighing 68 kg to 136 kg to altitudes of 118 km to 113 km, respectively. Both vehicles utilize the XM22E8 Hawk rocket motor which is available in large numbers as a surplus item from the U.S. Army. The Hawk fin and tail can hardware were designed in-house. The Nike tail can and fin hardware are surplus Nike-Ajax booster hardware. Development objectives were to provide a vehicle family with a larger diameter, larger volume payload capability than the Nike-Apache and Nike-Tomahawk vehicles at comparable cost. Both vehicles performed nominally in flight tests.

  11. Effect of Temperature on Mechanical Properties of Solid Rocket Propellants

    Directory of Open Access Journals (Sweden)

    Himanshu Shekhar

    2011-10-01

    Full Text Available Mechanical properties of solid rocket propellants are dependent on temperature. Any change in temperature brings significant change in the tensile strength, percentage elongation, and elastic modulus of the propellant. Different classes of operational solid rocket propellants namely extruded double-base propellants, composite, extruded composite and nitrarte ester polyester propellants were evaluated at different temperatures in the operating range of the rockets and missiles preferably in the range of –50 oC to +55 oC. It was observed that for each class of propellant, as temperature reduces, propellant becomes hard. This is depicted by increase in elastic modulus and tensile strength of the material. However, trend of percentage elongation is not very uniform. Extruded double-base propellants show less percentage elongation (around 1 per cent at reduced temperature (–50 oC probably due to brittleness. So is the trend with case-bonded composite propellants. However, reverse trend is exhibited by cartridge-loaded composite propellants and nitrate ester polyester propellants. Such propellants show higher percentage elongation (6 per cent for CLCP and 35 per cent for NEPE at reduced temperature (–50 oC. This makes such propellants tough and more area under stress-strain curve at reduced temperature is observed.Defence Science Journal, 2011, 61(6, pp.529-533, DOI:http://dx.doi.org/10.14429/dsj.61.774

  12. Dynamic mechanical analysis of double base rocket propellants

    Directory of Open Access Journals (Sweden)

    Marcin Cegła

    2016-03-01

    Full Text Available The article presents dynamic mechanical analysis (DMA for solid rocket propellants testing. Principles of operation and measured values are briefly described. The authors refer to the previous research of PTFE material and literature data providing information about proper experimental conditions and influence of measurement frequency, load amplitude, and heating rate on the results of DMA tests. The experimental results of solid double-base rocket propellant testing obtained on the N Netzsch DMA 242 device are presented. Mechanical properties such as the dynamic storage modulus E´, the dynamic loss modulus E˝ and tan(δ were measured within temperature range from (–120°C to (+90°C at the heating rate of 1 K/min. The test sample was subjected to a dual cantilever multi-frequency test. Special attention was paid to determination of the glass transition temperature of the tested propellant in reference to the NATO standardization agreement 4540 as well as influence of the measurement frequency on the glass transition.[b]Keywords[/b]: Dynamic mechanical analysis, solid rocket propellants, glass transition temperature

  13. Thermal Barriers Developed for Solid Rocket Motor Nozzle Joints

    Science.gov (United States)

    Steinetz, Bruce M.; Dunlap, Patrick H., Jr.

    2000-01-01

    Space shuttle solid rocket motor case assembly joints are sealed with conventional O-ring seals that are shielded from 5500 F combustion gases by thick layers of insulation and by special joint-fill compounds that fill assembly splitlines in the insulation. On a number of occasions, NASA has observed hot gas penetration through defects in the joint-fill compound of several of the rocket nozzle assembly joints. In the current nozzle-to-case joint, NASA has observed penetration of hot combustion gases through the joint-fill compound to the inboard wiper O-ring in one out of seven motors. Although this condition does not threaten motor safety, evidence of hot gas penetration to the wiper O-ring results in extensive reviews before resuming flight. The solid rocket motor manufacturer (Thiokol) approached the NASA Glenn Research Center at Lewis Field about the possibility of applying Glenn's braided fiber preform seal as a thermal barrier to protect the O-ring seals. Glenn and Thiokol are working to improve the nozzle-to-case joint design by implementing a more reliable J-leg design and by using a braided carbon fiber thermal barrier that would resist any hot gases that the J-leg does not block.

  14. Development of Thermal Barriers For Solid Rocket Motor Nozzle Joints

    Science.gov (United States)

    Steinetz, Bruce M.; Dunlap, Patrick H., Jr.

    2000-01-01

    Joints in the Space Shuttle solid rocket motors are sealed by O-rings to contain combustion gases inside the rocket that reach pressures of up to 900 psi and temperatures of up to 5500 F. To provide protection for the O-rings, the motors are insulated with either phenolic or rubber insulation. Gaps in the joints leading up to the O-rings are filled with polysulfide joint-fill compounds as an additional level of protection. The current RSRM nozzle-to-case joint design incorporating primary, secondary, and wiper O-rings experiences gas paths through the joint-fill compound to the innermost wiper O-ring in about one out of every seven motors. Although this does not pose a safety hazard to the motor, it is an undesirable condition that NASA and rocket manufacturer Thiokol want to eliminate. Each nozzle-to-case joint gas path results in extensive reviews and evaluation before flights can be resumed. Thiokol and NASA Marshall are currently working to improve the nozzle-to-case joint design by implementing a more reliable J-leg design that has been used successfully in the field and igniter joint. They are also planning to incorporate the NASA Glenn braided carbon fiber thermal barrier into the joint. The thermal barrier would act as an additional level of protection for the O-rings and allow the elimination of the joint-fill compound from the joint.

  15. Nonlinear Control of a Reusable Rocket Engine for Life Extension

    Science.gov (United States)

    Lorenzo, Carl F.; Holmes, Michael S.; Ray, Asok

    1998-01-01

    This paper presents the conceptual development of a life-extending control system where the objective is to achieve high performance and structural durability of the plant. A life-extending controller is designed for a reusable rocket engine via damage mitigation in both the fuel (H2) and oxidizer (O2) turbines while achieving high performance for transient responses of the combustion chamber pressure and the O2/H2 mixture ratio. The design procedure makes use of a combination of linear and nonlinear controller synthesis techniques and also allows adaptation of the life-extending controller module to augment a conventional performance controller of the rocket engine. The nonlinear aspect of the design is achieved using non-linear parameter optimization of a prescribed control structure. Fatigue damage in fuel and oxidizer turbine blades is primarily caused by stress cycling during start-up, shutdown, and transient operations of a rocket engine. Fatigue damage in the turbine blades is one of the most serious causes for engine failure.

  16. Robust lateral pulse jet control of an atmospheric rocket

    Science.gov (United States)

    Burchett, Bradley Thomas

    Uncontrolled direct fire rockets exhibit high impact point dispersion, even at relatively short range, and as such have been employed as area weapons on the battlefield. In order to reduce the dispersion of a direct fire rocket, feedback control is employed to fire short-duration solid rocket pulses mounted near the nose of the projectile and acting perpendicular to the projectile axis of symmetry. The feedback law is developed by first determining a piece wise linear model of the projectile swerving motion, subsequently using this linear model to predict the projectile impact point both with and without control, and using the results to command pulses at appropriate times to drive the impact point closer to the specified target. Candidate optimal control laws are formed using rules based on decision grids, and a global control strategy search algorithm. The global search control law proves to be prohibitively computationally expensive for on-line implementation. The performance of the baseline control law is found to be comparable to the rule based and global search optimal control laws. The control gains of the baseline control law are optimized in the presence of parametric plant uncertainty using a Monte Carlo simulation. Performance of the system in the presence of parametric plant uncertainty using the optimized gains is deemed comparable to performance of the baseline controller with no plant uncertainty. The level of uncertainty of several plant parameters is varied in order to compare robustness of the controller when optimized with uncertainty viz. without uncertainty.

  17. The Rocket Balloon (Rocketball): Applications to Science, Technology, and Education

    Science.gov (United States)

    Esper, Jaime

    2009-01-01

    Originally envisioned to study upper atmospheric phenomena, the Rocket Balloon system (or Rocketball for short) has utility in a range of applications, including sprite detection and in-situ measurements, near-space measurements and calibration correlation with orbital assets, hurricane observation and characterization, technology testing and validation, ground observation, and education. A salient feature includes the need to reach space and near-space within a critical time-frame and in adverse local meteorological conditions. It can also provide for the execution of technology validation and operational demonstrations at a fraction of the cost of a space flight. In particular, planetary entry probe proof-of-concepts can be examined. A typical Rocketball operational scenario consists of a sounding rocket launch and subsequent deployment of a balloon above a desired location. An obvious advantage of this combination is the additional mission 'hang-time' rendered by the balloon once the sounding rocket flight is completed. The system leverages current and emergent technologies at the NASA Goddard Space Flight Center and other organizations.

  18. MEMS-Based Solid Propellant Rocket Array Thruster

    Science.gov (United States)

    Tanaka, Shuji; Hosokawa, Ryuichiro; Tokudome, Shin-Ichiro; Hori, Keiichi; Saito, Hirobumi; Watanabe, Masashi; Esashi, Masayoshi

    The prototype of a solid propellant rocket array thruster for simple attitude control of a 10 kg class micro-spacecraft was completed and tested. The prototype has 10×10 φ0.8 mm solid propellant micro-rockets arrayed at a pitch of 1.2 mm on a 20×22 mm substrate. To realize such a dense array of micro-rockets, each ignition heater is powered from the backside of the thruster through an electrical feedthrough which passes along a propellant cylinder wall. Boron/potassium nitrate propellant (NAB) is used with/without lead rhodanide/potassium chlorate/nitrocellulose ignition aid (RK). Impulse thrust was measured by a pendulum method in air. Ignition required electric power of at least 3 4 W with RK and 4 6 W without RK. Measured impulse thrusts were from 2×10-5 Ns to 3×10-4 Ns after the calculation of compensation for air dumping.

  19. A research on polyether glycol replaced APCP rocket propellant

    Science.gov (United States)

    Lou, Tianyou; Bao, Chun Jia; Wang, Yiyang

    2017-08-01

    Ammonium perchlorate composite propellant (APCP) is a modern solid rocket propellant used in rocket vehicles. It differs from many traditional solid rocket propellants by the nature of how it is processed. APCP is cast into shape, as opposed to powder pressing it with black powder. This provides manufacturing regularity and repeatability, which are necessary requirements for use in the aerospace industry. For traditional APCP, ingredients normally used are ammonium peroxide, aluminum, Hydroxyl-terminated polybutadiene(HTPB), curing agency and other additives, the greatest disadvantage is that the fuel is too expensive. According to the price we collected in our country, a single kilogram of this fuel will cost 200 Yuan, which is about 35 dollars, for a fan who may use tons of the fuel in a single year, it definitely is a great deal of money. For this reason, we invented a new kind of APCP fuel. Changing adhesive agency from cross-linked htpb to cross linked polyether glycol gives a similar specific thrust, density and mechanical property while costs a lower price.

  20. SLS Test Stand Site Selection

    Science.gov (United States)

    Crowe, Kathryn; Williams, Michael

    2015-01-01

    Test site selection is a critical element of the design, development and production of a new system. With the advent of the new Space Launch System (SLS), the National Aeronautics and Space Administration (NASA) had a number of test site selection decisions that needed to be made early enough in the Program to support the planned Launch Readiness Date (LRD). This case study focuses on decisions that needed to be made in 2011 and 2012 in preparation for the April 2013 DPMC decision about where to execute the Main Propulsion Test that is commonly referred to as "Green Run." Those decisions relied upon cooperative analysis between the Program, the Test Lab and Center Operations. The SLS is a human spaceflight vehicle designed to carry a crew farther into space than humans have previously flown. The vehicle consists of four parts: the crew capsule, the upper stage, the core stage, and the first stage solid rocket boosters. The crew capsule carries the astronauts, while the upper stage, the core stage, and solid rocket boosters provide thrust for the vehicle. In other words, the stages provide the "lift" part of the lift vehicle. In conjunction with the solid rocket boosters, the core stage provides the initial "get-off-the-ground" thrust to the vehicle. The ignition of the four core stage engines and two solid rocket boosters is the first step in the launch portion of the mission. The solid rocket boosters burn out after about 2 minutes of flight, and are then jettisoned. The core stage provides thrust until the vehicle reaches a specific altitude and speed, at which point the core stage is shut off and jettisoned, and the upper stage provides vehicle thrust for subsequent mission trajectories. The integrated core stage primarily consists of a liquid oxygen tank, a liquid hydrogen tank, and the four core stage engines. For the SLS program, four RS-25 engines were selected as the four core stage engines. The RS-25 engine is the same engine that was used for Space

  1. Studies of Fission Fragment Rocket Engine Propelled Spacecraft

    Science.gov (United States)

    Werka, Robert O.; Clark, Rodney; Sheldon, Rob; Percy, Thomas K.

    2014-01-01

    The NASA Office of Chief Technologist has funded from FY11 through FY14 successive studies of the physics, design, and spacecraft integration of a Fission Fragment Rocket Engine (FFRE) that directly converts the momentum of fission fragments continuously into spacecraft momentum at a theoretical specific impulse above one million seconds. While others have promised future propulsion advances if only you have the patience, the FFRE requires no waiting, no advances in physics and no advances in manufacturing processes. Such an engine unequivocally can create a new era of space exploration that can change spacecraft operation. The NIAC (NASA Institute for Advanced Concepts) Program Phase 1 study of FY11 first investigated how the revolutionary FFRE technology could be integrated into an advanced spacecraft. The FFRE combines existent technologies of low density fissioning dust trapped electrostatically and high field strength superconducting magnets for beam management. By organizing the nuclear core material to permit sufficient mean free path for escape of the fission fragments and by collimating the beam, this study showed the FFRE could convert nuclear power to thrust directly and efficiently at a delivered specific impulse of 527,000 seconds. The FY13 study showed that, without increasing the reactor power, adding a neutral gas to the fission fragment beam significantly increased the FFRE thrust through in a manner analogous to a jet engine afterburner. This frictional interaction of gas and beam resulted in an engine that continuously produced 1000 pound force of thrust at a delivered impulse of 32,000 seconds, thereby reducing the currently studied DRM 5 round trip mission to Mars from 3 years to 260 days. By decreasing the gas addition, this same engine can be tailored for much lower thrust at much higher impulse to match missions to more distant destinations. These studies created host spacecraft concepts configured for manned round trip journeys. While the

  2. Tibetan antelope cystathionine γ -lyase:complete cDNA sequences%高原藏羚羊胱硫醚-γ-裂解酶基因克隆与全序列测定

    Institute of Scientific and Technical Information of China (English)

    李肃; 格日力

    2013-01-01

    Objective To identify the Cystathionine-γ-Lyase(CSE) genes coding sequences molecular cloning , exam the tissues expression spectrums and discuss the hypoxic adaptations mechanisms in Tibetan antelope .Methods The total RNA was extracted ,and the cDNA was captured by reverse transcription RT-PCR ,then identified ,se-quenced and cloned .Results There was 96 .47% homology between the Tibetan antelope gene fragment containing the purpose gene and the cattle gene in gen banks ,thus the result mean the gene which cloned before was CSE gene protein .The length of the CSE gene protein was been detected by designing primers according to the human ,mous , wild boar ,cattle CSEcDNA sequences ,and the CSE gene primers of tibetan antelope which tesied by Pnaman .Conclu-sion CSE gene protein might play an important role in the body of the Tibetan anteplope ,which provide experiment basis to the gene study about adaptation in high altitude hypoxia environment .in the future .%目的:探讨克隆高原藏羚羊胱硫醚-γ-裂解酶(CSE)基因编码区并检测其在成年高原藏羚羊组织中的表达,同时探讨高原藏羚羊低氧适应的分子生物学机制。方法从高原藏羚羊组织中提取总 RNA ,通过逆转录聚合酶链反应(RT-PCR)获得高原藏羚羊 cDNA ,并进行鉴定和测序。结果将含有目的片段克隆后经测序和 Blast分析,结果显示其部分编码序列与 GenBank 中牛 CSE 蛋白基因序列同源性96.47%,表明本实验所克隆的序列为CSE 蛋白基因。根据已知人、褐家鼠、小鼠、野猪、食蟹猴、家牛 CSEcDNA 序列和 Pnaman 软件设计高原藏羚羊 cse基因的引物。结论 CSE mRNA 可能在高原藏羚羊机体较为广泛的区域中发挥着作用,同时为高原低氧适应相关基因的研究提供了实验依据。

  3. Rivaroxaban-once daily, oral, direct factor Xa inhibition compared with vitamin K antagonism for prevention of stroke and Embolism Trial in Atrial Fibrillation: rationale and design of the ROCKET AF study

    DEFF Research Database (Denmark)

    NN, NN

    2010-01-01

    in advanced development as an alternative to warfarin for the prevention and treatment of thromboembolic disorders. METHODS: ROCKET AF is a randomized, double-blind, double-dummy, event-driven trial, which aims to establish the noninferiority of rivaroxaban compared with warfarin in patients with nonvalvular...... nonmajor bleeding events. Over 14,000 patients have been randomized at 1,100 sites across 45 countries, and will be followed until 405 primary outcome events are observed. CONCLUSION: The ROCKET AF study will determine the efficacy and safety of rivaroxaban as an alternative to warfarin for the prevention...

  4. Reactive Inkjet Printing of Biocompatible Enzyme Powered Silk Micro-Rockets.

    Science.gov (United States)

    Gregory, David A; Zhang, Yu; Smith, Patrick J; Zhao, Xiubo; Ebbens, Stephen J

    2016-08-01

    Inkjet-printed enzyme-powered silk-based micro-rockets are able to undergo autonomous motion in a vast variety of fluidic environments including complex media such as human serum. By means of digital inkjet printing it is possible to alter the catalyst distribution simply and generate varying trajectory behavior of these micro-rockets. Made of silk scaffolds containing enzymes these micro-rockets are highly biocompatible and non-biofouling.

  5. On the Elastic Vibration Model for High Length-Diameter Ratio Rocket with Attitude Control System

    Institute of Scientific and Technical Information of China (English)

    朱伯立; 杨树兴

    2003-01-01

    An elastic vibration model for high length-diameter ratio spinning rocket with attitude control system which can be used for trajectory simulation is established. The basic theory of elastic dynamics and vibration dynamics were both used to set up the elastic vibration model of rocket body. In order to study the problem more conveniently, the rocket's body was simplified to be an even beam with two free ends. The model was validated by simulation results and the test data.

  6. Sublimation of ice particles from rocket exhausts in the upper atmosphere

    OpenAIRE

    2003-01-01

    The process of sublimation of ice particles from a rocket exhaust in the upper atmosphere is examined. Heating by solar radiation and losses of energy by means thermal radiation and sublimation are taken into account in the thermal balance of the ice particles. The time dependences of size and temperature of the ice particles are obtained. An estimation of water vapor concentration around the rocket trajectory is made. The process of sublimation of the rocket exhaust ice particles may be impo...

  7. Numerical Calculation of Effect of Elastic Deformation on Aerodynamic Characteristics of a Rocket

    OpenAIRE

    2014-01-01

    The application and workflow of Computational Fluid Dynamics (CFD)/Computational Structure Dynamics (CSD) on solving the static aeroelastic problem of a slender rocket are introduced. To predict static aeroelastic behavior accurately, two-way coupling and inertia relief methods are used to calculate the static deformations and aerodynamic characteristics of the deformed rocket. The aerodynamic coefficients of rigid rocket are computed firstly and compared with the experimental data, which ver...

  8. Design Rules and Issues with Respect to Rocket Based Combined Cycles

    Science.gov (United States)

    2010-09-01

    Section Analysis As we seek for the accelerator, the inlet design is quite art of compromise. To make benefits due to air- breathing propulsion, the...Design Rules and Issues with Respect to Rocket Based Combined Cycles 3 - 4 RTO-EN-AVT-185 2.1.2 Combustor Section Analysis Embedded rocket chamber...cause thrust augmentation due to the ejector effects, which in turn, can reduce the requirement for the rocket engine output. In the speed regime with

  9. Flight Testing a Real-Time Hazard Detection System for Safe Lunar Landing on the Rocket-Powered Morpheus Vehicle

    Science.gov (United States)

    Trawny, Nikolas; Huertas, Andres; Luna, Michael E.; Villalpando, Carlos Y.; Martin, Keith E.; Carson, John M.; Johnson, Andrew E.; Restrepo, Carolina; Roback, Vincent E.

    2015-01-01

    The Hazard Detection System (HDS) is a component of the ALHAT (Autonomous Landing and Hazard Avoidance Technology) sensor suite, which together provide a lander Guidance, Navigation and Control (GN&C) system with the relevant measurements necessary to enable safe precision landing under any lighting conditions. The HDS consists of a stand-alone compute element (CE), an Inertial Measurement Unit (IMU), and a gimbaled flash LIDAR sensor that are used, in real-time, to generate a Digital Elevation Map (DEM) of the landing terrain, detect candidate safe landing sites for the vehicle through Hazard Detection (HD), and generate hazard-relative navigation (HRN) measurements used for safe precision landing. Following an extensive ground and helicopter test campaign, ALHAT was integrated onto the Morpheus rocket-powered terrestrial test vehicle in March 2014. Morpheus and ALHAT then performed five successful free flights at the simulated lunar hazard field constructed at the Shuttle Landing Facility (SLF) at Kennedy Space Center, for the first time testing the full system on a lunar-like approach geometry in a relevant dynamic environment. During these flights, the HDS successfully generated DEMs, correctly identified safe landing sites and provided HRN measurements to the vehicle, marking the first autonomous landing of a NASA rocket-powered vehicle in hazardous terrain. This paper provides a brief overview of the HDS architecture and describes its in-flight performance.

  10. Flight Testing a Real-Time Hazard Detection System for Safe Lunar Landing on the Rocket-Powered Morpheus Vehicle

    Science.gov (United States)

    Trawny, Nikolas; Huertas, Andres; Luna, Michael E.; Villalpando, Carlos Y.; Martin, Keith E.; Carson, John M.; Johnson, Andrew E.; Restrepo, Carolina; Roback, Vincent E.

    2015-01-01

    The Hazard Detection System (HDS) is a component of the ALHAT (Autonomous Landing and Hazard Avoidance Technology) sensor suite, which together provide a lander Guidance, Navigation and Control (GN&C) system with the relevant measurements necessary to enable safe precision landing under any lighting conditions. The HDS consists of a stand-alone compute element (CE), an Inertial Measurement Unit (IMU), and a gimbaled flash LIDAR sensor that are used, in real-time, to generate a Digital Elevation Map (DEM) of the landing terrain, detect candidate safe landing sites for the vehicle through Hazard Detection (HD), and generate hazard-relative navigation (HRN) measurements used for safe precision landing. Following an extensive ground and helicopter test campaign, ALHAT was integrated onto the Morpheus rocket-powered terrestrial test vehicle in March 2014. Morpheus and ALHAT then performed five successful free flights at the simulated lunar hazard field constructed at the Shuttle Landing Facility (SLF) at Kennedy Space Center, for the first time testing the full system on a lunar-like approach geometry in a relevant dynamic environment. During these flights, the HDS successfully generated DEMs, correctly identified safe landing sites and provided HRN measurements to the vehicle, marking the first autonomous landing of a NASA rocket-powered vehicle in hazardous terrain. This paper provides a brief overview of the HDS architecture and describes its in-flight performance.

  11. Monitoring on zoonosis in field research of Tibetan antelope%藏羚羊野外现场研究工作中人兽共患病的监测

    Institute of Scientific and Technical Information of China (English)

    马韶辉; 陈洪舰; 吴海生; 格日力

    2012-01-01

    目的 随着经济发展和生物学研究的不断深入,野外现场研究工作将触及更多的野生动物,研究足迹将深入人类罕至的地区.这一行为大大增加了人兽共患病对人类社会的威胁.完善野生动物研究工作中人兽共患病的监测机制,有利于控制动物间疾病和疫情向人间蔓延.方法 采集6只成年野生藏羚羊血液进行鼠疫、布鲁氏菌、包虫病细粒棘球蚴血清学检测,采集脏器进行炭疽芽孢杆菌的分离培养.结果 检测鼠疫、炭疽和布鲁氏菌,血清学检验、细菌学培养均为阴性;包虫病细粒棘球蚴检测2只血清呈阳性(1∶8),阳性率为33%.结论 此次研究工作中的疾病监测保证了《藏羚羊基因组的研究》课题的正常进行,同时也为保护国家级保护动物、开展人兽共患病监测做出有益尝试.%Objective Along with the development of economy and biology, field research would involve more wild animals, and go deep into some sparsely populated areas, which would greatly increase the threat of zoonosis to liiijnan and society. Improving the monitoring mechanism of zoonosis of wild animal research would con-tori the spread of animal diseases to human. Method Collect blood and visceral organ samples from six adult wild Tibetan antelopes. The blood was detected with serological tests for plague, brucella and echinococcosis, and the visceral organs were separately cultured with bacillus anthracis. Results The results shown that the serological tests for plague, anthrax and brucella and bacterial culture were negative, and 2 cases were sero -positive of echinococcosis (1:8), with the positive rate of 33%. Conclusions This research ensured the normal development of the subject of Genome Research on Tibetan Antelope, and also made useful attempt to protect national animals and develop the monitoring of zoonosis.

  12. Numerical Calculation of Effect of Elastic Deformation on Aerodynamic Characteristics of a Rocket

    Directory of Open Access Journals (Sweden)

    Laith K. Abbas

    2014-01-01

    Full Text Available The application and workflow of Computational Fluid Dynamics (CFD/Computational Structure Dynamics (CSD on solving the static aeroelastic problem of a slender rocket are introduced. To predict static aeroelastic behavior accurately, two-way coupling and inertia relief methods are used to calculate the static deformations and aerodynamic characteristics of the deformed rocket. The aerodynamic coefficients of rigid rocket are computed firstly and compared with the experimental data, which verified the accuracy of CFD output. The results of the analysis for elastic rocket in the nonspinning and spinning states are compared with the rigid ones. The results highlight that the rocket deformation aspects are decided by the normal force distribution along the rocket length. Rocket deformation becomes larger with increasing the flight angle of attack. Drag and lift force coefficients decrease and pitching moment coefficients increase due to rocket deformations, center of pressure location forwards, and stability of the rockets decreases. Accordingly, the flight trajectory may be affected by the change of these aerodynamic coefficients and stability.

  13. Pershing II Simulation Studies. Debris Dynamics and 2.75 Rocket 6-DOF (Degree of Freedom).

    Science.gov (United States)

    1983-07-01

    impact (Radians) DIST - Distance to go (rocket to target) PID1 - Angular acceleration about rocket X-axis (degrees) Q1D1 - Angular acceleration about... PID1 - Angular Acceleration About Rocket X-Axis (Degrees) QID1 - Angular Acceleration About Rocket Y-Axis (Degrees) RID1 - Angular Acceleration...WINX=XX< WINY=XX( WINZ=WXY ALFO=0. IF(WINX. QID = SAO RID= RAO PID1 = RA DI3T-SQP •3101 = RA RID1 = RA ai = xx< TH = XX< Fl =AM0D IF(*0D

  14. Computational Thermochemistry of Jet Fuels and Rocket Propellants

    Science.gov (United States)

    Crawford, T. Daniel

    2002-01-01

    The design of new high-energy density molecules as candidates for jet and rocket fuels is an important goal of modern chemical thermodynamics. The NASA Glenn Research Center is home to a database of thermodynamic data for over 2000 compounds related to this goal, in the form of least-squares fits of heat capacities, enthalpies, and entropies as functions of temperature over the range of 300 - 6000 K. The chemical equilibrium with applications (CEA) program written and maintained by researchers at NASA Glenn over the last fifty years, makes use of this database for modeling the performance of potential rocket propellants. During its long history, the NASA Glenn database has been developed based on experimental results and data published in the scientific literature such as the standard JANAF tables. The recent development of efficient computational techniques based on quantum chemical methods provides an alternative source of information for expansion of such databases. For example, it is now possible to model dissociation or combustion reactions of small molecules to high accuracy using techniques such as coupled cluster theory or density functional theory. Unfortunately, the current applicability of reliable computational models is limited to relatively small molecules containing only around a dozen (non-hydrogen) atoms. We propose to extend the applicability of coupled cluster theory- often referred to as the 'gold standard' of quantum chemical methods- to molecules containing 30-50 non-hydrogen atoms. The centerpiece of this work is the concept of local correlation, in which the description of the electron interactions- known as electron correlation effects- are reduced to only their most important localized components. Such an advance has the potential to greatly expand the current reach of computational thermochemistry and thus to have a significant impact on the theoretical study of jet and rocket propellants.

  15. Fuel-Cell Power Source Based on Onboard Rocket Propellants

    Science.gov (United States)

    Ganapathi, Gani; Narayan, Sri

    2010-01-01

    The use of onboard rocket propellants (dense liquids at room temperature) in place of conventional cryogenic fuel-cell reactants (hydrogen and oxygen) eliminates the mass penalties associated with cryocooling and boil-off. The high energy content and density of the rocket propellants will also require no additional chemical processing. For a 30-day mission on the Moon that requires a continuous 100 watts of power, the reactant mass and volume would be reduced by 15 and 50 percent, respectively, even without accounting for boiloff losses. The savings increase further with increasing transit times. A high-temperature, solid oxide, electrolyte-based fuel-cell configuration, that can rapidly combine rocket propellants - both monopropellant system with hydrazine and bi-propellant systems such as monomethyl hydrazine/ unsymmetrical dimethyl hydrazine (MMH/UDMH) and nitrogen tetroxide (NTO) to produce electrical energy - overcomes the severe drawbacks of earlier attempts in 1963-1967 of using fuel reforming and aqueous media. The electrical energy available from such a fuel cell operating at 60-percent efficiency is estimated to be 1,500 Wh/kg of reactants. The proposed use of zirconia-based oxide electrolyte at 800-1,000 C will permit continuous operation, very high power densities, and substantially increased efficiency of conversion over any of the earlier attempts. The solid oxide fuel cell is also tolerant to a wide range of environmental temperatures. Such a system is built for easy refueling for exploration missions and for the ability to turn on after several years of transit. Specific examples of future missions are in-situ landers on Europa and Titan that will face extreme radiation and temperature environments, flyby missions to Saturn, and landed missions on the Moon with 14 day/night cycles.

  16. Axisymmetric Numerical Modeling of Pulse Detonation Rocket Engines

    Science.gov (United States)

    Morris, Christopher I.

    2005-01-01

    Pulse detonation rocket engines (PDREs) have generated research interest in recent years as a chemical propulsion system potentially offering improved performance and reduced complexity compared to conventional rocket engines. The detonative mode of combustion employed by these devices offers a thermodynamic advantage over the constant-pressure deflagrative combustion mode used in conventional rocket engines and gas turbines. However, while this theoretical advantage has spurred considerable interest in building PDRE devices, the unsteady blowdown process intrinsic to the PDRE has made realistic estimates of the actual propulsive performance problematic. The recent review article by Kailasanath highlights some of the progress that has been made in comparing the available experimental measurements with analytical and numerical models. In recent work by the author, a quasi-one-dimensional, finite rate chemistry CFD model was utilized to study the gasdynamics and performance characteristics of PDREs over a range of blowdown pressure ratios from 1-1000. Models of this type are computationally inexpensive, and enable first-order parametric studies of the effect of several nozzle and extension geometries on PDRE performance over a wide range of conditions. However, the quasi-one-dimensional approach is limited in that it cannot properly capture the multidimensional blast wave and flow expansion downstream of the PDRE, nor can it resolve nozzle flow separation if present. Moreover, the previous work was limited to single-pulse calculations. In this paper, an axisymmetric finite rate chemistry model is described and utilized to study these issues in greater detail. Example Mach number contour plots showing the multidimensional blast wave and nozzle exhaust plume are shown. The performance results are compared with the quasi-one-dimensional results from the previous paper. Both Euler and Navier-Stokes solutions are calculated in order to determine the effect of viscous

  17. Low Cost Nuclear Thermal Rocket Cermet Fuel Element Environment Testing

    Science.gov (United States)

    Bradley, D. E.; Mireles, O. R.; Hickman, R. R.

    2011-01-01

    Deep space missions with large payloads require high specific impulse and relatively high thrust to achieve mission goals in reasonable time frames.1,2 Conventional storable propellants produce average specific impulse. Nuclear thermal rockets capable of producing high specific impulse are proposed. Nuclear thermal rockets employ heat produced by fission reaction to heat and therefore accelerate hydrogen, which is then forced through a rocket nozzle providing thrust. Fuel element temperatures are very high (up to 3000 K), and hydrogen is highly reactive with most materials at high temperatures. Data covering the effects of high-temperature hydrogen exposure on fuel elements are limited.3 The primary concern is the mechanical failure of fuel elements that employ high-melting-point metals, ceramics, or a combination (cermet) as a structural matrix into which the nuclear fuel is distributed. The purpose of the testing is to obtain data to assess the properties of the non-nuclear support materials, as-fabricated, and determine their ability to survive and maintain thermal performance in a prototypical NTR reactor environment of exposure to hydrogen at very high temperatures. The fission process of the planned fissile material and the resulting heating performance is well known and does not therefore require that active fissile material be integrated in this testing. A small-scale test bed designed to heat fuel element samples via non-contact radio frequency heating and expose samples to hydrogen is being developed to assist in optimal material and manufacturing process selection without employing fissile material. This paper details the test bed design and results of testing conducted to date.

  18. Testing of electroformed deposited iridium/powder metallurgy rhenium rockets

    Science.gov (United States)

    Reed, Brian D.; Dickerson, Robert

    1996-01-01

    High-temperature, oxidation-resistant chamber materials offer the thermal margin for high performance and extended lifetimes for radiation-cooled rockets. Rhenium (Re) coated with iridium (Ir) allow hours of operation at 2200 C on Earth-storable propellants. One process for manufacturing Ir/Re rocket chambers is the fabrication of Re substrates by powder metallurgy (PM) and the application of Ir coatings by using electroformed deposition (ED). ED Ir coatings, however, have been found to be porous and poorly adherent. The integrity of ED Ir coatings could be improved by densification after the electroforming process. This report summarizes the testing of two 22-N, ED Ir/PM Re rocket chambers that were subjected to post-deposition treatments in an effort to densify the Ir coating. One chamber was vacuum annealed, while the other chamber was subjected to hot isostatic pressure (HIP). The chambers were tested on gaseous oxygen/gaseous hydrogen propellants, at mixture ratios that simulated the oxidizing environments of Earth-storable propellants. ne annealed ED Ir/PM Re chamber was tested for a total of 24 firings and 4.58 hr at a mixture ratio of 4.2. After only 9 firings, the annealed ED Ir coating began to blister and spall upstream of the throat. The blistering and spalling were similar to what had been experienced with unannealed, as-deposited ED Ir coatings. The HIP ED Ir/PM Re chamber was tested for a total of 91 firings and 11.45 hr at mixture ratios of 3.2 and 4.2. The HIP ED Ir coating remained adherent to the Re substrate throughout testing; there were no visible signs of coating degradation. Metallography revealed, however, thinning of the HIP Ir coating and occasional pores in the Re layer upstream of the throat. Pinholes in the Ir coating may have provided a path for oxidation of the Re substrate at these locations. The HIP ED Ir coating proved to be more effective than vacuum annealed and as-deposited ED Ir. Further densification is still required to

  19. A weak equivalence principle test on a suborbital rocket

    CERN Document Server

    Reasenberg, Robert D

    2010-01-01

    We describe a Galilean test of the weak equivalence principle, to be conducted during the free fall portion of a sounding rocket flight. The test of a single pair of substances is aimed at a measurement uncertainty of sigma(eta) < 10^-16 after averaging the results of eight separate drops. The weak equivalence principle measurement is made with a set of four laser gauges that are expected to achieve 0.1 pm Hz^-1/2. The discovery of a violation (eta not equal to 0) would have profound implications for physics, astrophysics, and cosmology.

  20. Weak Equivalence Principle Test on a Sounding Rocket

    CERN Document Server

    Phillips, James D; Popescu, Eugeniu M; Rocco, Emanuele; Thapa, Rajesh; Reasenberg, Robert D; Lorenzini, Enrico C

    2010-01-01

    SR-POEM, our principle of equivalence measurement on a sounding rocket, will compare the free fall rate of two substances yielding an uncertainty of E-16 in the estimate of \\eta. During the past two years, the design concept has matured and we have been working on the required technology, including a laser gauge that is self aligning and able to reach 0.1 pm per root hertz for periods up to 40 s. We describe the status and plans for this project.