WorldWideScience

Sample records for repair engine cooling

  1. 46 CFR 119.420 - Engine cooling.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Engine cooling. 119.420 Section 119.420 Shipping COAST... Machinery Requirements § 119.420 Engine cooling. (a) Except as otherwise provided in paragraph (b) of this section, all engines must be water cooled and meet the requirements of this paragraph. (1) The engine...

  2. 46 CFR 182.420 - Engine cooling.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Engine cooling. 182.420 Section 182.420 Shipping COAST...) MACHINERY INSTALLATION Specific Machinery Requirements § 182.420 Engine cooling. (a) Except as otherwise provided in paragraphs (b), (c), (d), and (e) of this section, all engines must be water cooled and...

  3. 14 CFR 33.21 - Engine cooling.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine cooling. 33.21 Section 33.21 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; General § 33.21 Engine cooling. Engine design...

  4. Performance of Air-cooled Engine Cylinders Using Blower Cooling

    Science.gov (United States)

    Schey, Oscar W; Ellerbrock, Herman H , Jr

    1936-01-01

    An investigation was made to obtain information on the minimum quantity of air and power required to cool conventional air cooled cylinders at various operating conditions when using a blower. The results of these tests show that the minimum power required for satisfactory cooling with an overall blower efficiency of 100 percent varied from 2 to 6 percent of the engine power depending on the operating conditions. The shape of the jacket had a large effect on the cylinder temperatures. Increasing the air speed over the front of the cylinder by keeping the greater part of the circumference of the cylinder covered by the jacket reduced the temperatures over the entire cylinder.

  5. Engine room cooling system using jet pump

    Energy Technology Data Exchange (ETDEWEB)

    Lim, J.W.; Lee, S.H. [Daewoo Heavy Industries Ltd. (Korea)

    2000-04-01

    Construction machinery includes an engine enclosure separated from a cooling system enclosure by a wall to reduce noise and advance cooling system performance. For this structure, however, the axial fan cannot be of benefit to the engine room, and so the temperature rise in the engine room makes several bad conditions. This paper proposes that hot air in engine room is evacuated by secondary pipe using jet pump. This paper demonstrates the structure and the effect of jet pump and useful guideline on design of area, length, and shape of secondary pipe to maximize the effect of jet pump. (author). 4 refs., 7 figs., 5 tabs.

  6. 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.

  7. Performance testing of engineered corium cooling systems

    Energy Technology Data Exchange (ETDEWEB)

    Lomperski, S., E-mail: lomperski@anl.gov [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439-4840 (United States); Farmer, M.T. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439-4840 (United States)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Experiments tested two engineered corium cooling systems. Black-Right-Pointing-Pointer The systems passively inject water into corium from below. Black-Right-Pointing-Pointer These systems cool corium much faster than top flooding. - Abstract: The coolability of ex-vessel core debris continues to be an issue of concern in the realm of light water reactor safety. Extensive research into corium/concrete interaction phenomena has been unable to establish the certainty of melt quench and stabilization within the containment boundary for all credible cases of cooling restricted to top flooding. As a result, there has been continuing interest in engineered systems that can augment cooling. This paper describes the testing of two passive cooling concepts that inject water into corium from below via nozzles embedded within the basemat: one with porous concrete nozzles and the other with a type of composite nozzle. The latter supplements water injection with noncondensable gas to stabilize flow and suppress vapor explosions. Each test involved a 136 kg melt composed of 56/23/14 wt% UO{sub 2}/ZrO{sub 2}/siliceous concrete at an initial depth of 30 cm. The setup with the porous concrete nozzles successfully injected water into the melt at heads as low as 2.3 m. The composite nozzle test was partially successful, with three nozzles delivering coolant while a fourth was damaged by the melt and failed to inject water. The melts cooled twice as fast as similar ones tested in a top flooding configuration. These experiments confirmed earlier work at Forschungszentrum Karlsruhe and elsewhere indicating that cooling via bottom water injection is a particularly effective method for quenching ex-vessel corium melts.

  8. 40 CFR 1065.122 - Engine cooling and lubrication.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Engine cooling and lubrication. 1065.122 Section 1065.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... lubrication. (a) Engine cooling. Cool the engine during testing so its intake-air, oil, coolant, block,...

  9. 46 CFR 182.425 - Engine exhaust cooling.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Engine exhaust cooling. 182.425 Section 182.425 Shipping...) MACHINERY INSTALLATION Specific Machinery Requirements § 182.425 Engine exhaust cooling. (a) Except as... of this chapter. (b) The exhaust pipe cooling water system must comply with the requirements of...

  10. Strategies for cell engineering in tissue repair.

    Science.gov (United States)

    Brown, R A; Smith, K D; Angus McGrouther, D

    1997-01-01

    Cellular and tissue engineering are new areas of research, currently attracting considerable interest because of the remarkable potential they have for clinical application. Some claims have indeed been dramatic, including the possibility of growing complete, artificial organs, such as the liver. However, amid such long-term aspirations there is the very real possibility that small tissues (artificial grafts) may be fabricated in the near future for use in reconstructive surgery. Logically, we should focus on how it is possible to produce modest, engineered tissues for tissue repair. It is evident that strategies to date either depend on innate information within implanted cells, to reform the target tissue or aim to provide appropriate environmental cues or guidance to direct cell behavior. It is argued here that present knowledge of tissue repair biology points us toward the latter approach, providing external cues which will direct how cells should organize the new tissue. This will be particularly true where we need to reproduce microscopic and ultrastructural features of the original tissue architecture. A number of such cues have been identified, and methods are already available, including substrate chemistry, substrate contact guidance, mechanical loading, and biochemical mediators to provide these cues. Examples of these are already being used with some success to control the formation of tissue structures.

  11. LOX/Methane Regeneratively-Cooled Rocket Engine Development Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Design, build, and test a 5,000 lbf thrust regeneratively cooled combustion chamber at JSC for a low pressure liquid oxygen/methane engine. The engine demonstrates...

  12. Low pressure cooling seal system for a gas turbine engine

    Science.gov (United States)

    Marra, John J

    2014-04-01

    A low pressure cooling system for a turbine engine for directing cooling fluids at low pressure, such as at ambient pressure, through at least one cooling fluid supply channel and into a cooling fluid mixing chamber positioned immediately downstream from a row of turbine blades extending radially outward from a rotor assembly to prevent ingestion of hot gases into internal aspects of the rotor assembly. The low pressure cooling system may also include at least one bleed channel that may extend through the rotor assembly and exhaust cooling fluids into the cooling fluid mixing chamber to seal a gap between rotational turbine blades and a downstream, stationary turbine component. Use of ambient pressure cooling fluids by the low pressure cooling system results in tremendous efficiencies by eliminating the need for pressurized cooling fluids for sealing this gap.

  13. Development of Air-cooled Engines with Blower Cooling

    Science.gov (United States)

    Lohner, Kurt

    1933-01-01

    With the aid of a heating device, the heat transfer to cylinders with conical fins of various forms is determined both for shrouded and exposed cylinders. Simultaneously the pressure drop for overcoming the resistance to the motion of air between the fins of the enclosed cylinder is measured. Thus the relations between the heat transfer and the energy required for cooling are discovered. The investigations show that the heat transfer in a conducted air flow is much greater than in a free current and that further improvement, as compared with free exposure, is possible through narrower spaces between the fins.

  14. Investigation of the cooling film distribution in liquid rocket engine

    Directory of Open Access Journals (Sweden)

    Luís Antonio Silva

    2011-05-01

    Full Text Available This study presents the results of the investigation of a cooling method widely used in the combustion chambers, which is called cooling film, and it is applied to a liquid rocket engine that uses as propellants liquid oxygen and kerosene. Starting from an engine cooling, whose film is formed through the fuel spray guns positioned on the periphery of the injection system, the film was experimentally examined, it is formed by liquid that seeped through the inner wall of the combustion chamber. The parameter used for validation and refinement of the theoretical penetration of the film was cooling, as this parameter is of paramount importance to obtain an efficient thermal protection inside the combustion chamber. Cold tests confirmed a penetrating cold enough cooling of the film for the length of the combustion chamber of the studied engine.

  15. Raman Cooling of Solids through Photonic Density of States Engineering

    CERN Document Server

    Chen, Yin-Chung

    2015-01-01

    The laser cooling of vibrational states of solids has been achieved through photoluminescence in rare-earth elements, optical forces in optomechanics, and the Brillouin scattering light-sound interaction. The net cooling of solids through spontaneous Raman scattering, and laser refrigeration of indirect band gap semiconductors, both remain unsolved challenges. Here, we analytically show that photonic density of states (DoS) engineering can address the two fundamental requirements for achieving spontaneous Raman cooling: suppressing the dominance of Stokes (heating) transitions, and the enhancement of anti-Stokes (cooling) efficiency beyond the natural optical absorption of the material. We develop a general model for the DoS modification to spontaneous Raman scattering probabilities, and elucidate the necessary and minimum condition required for achieving net Raman cooling. With a suitably engineered DoS, we establish the enticing possibility of refrigeration of intrinsic silicon by annihilating phonons from ...

  16. Helical Muon Beam Cooling Channel Engineering Design

    Energy Technology Data Exchange (ETDEWEB)

    Kashikhin, V.S.; Lopes, M.L.; Romanov, G.V.; Tartaglia, M.A.; Yonehara, K.; Yu, M.; Zlobin, A.V.; /Fermilab; Flanagan, G.; Johnson, R.P.; Kazakevich, G.M.; Marhauser, F.; /MUONS Inc., Batavia

    2012-05-01

    The Helical Cooling Channel (HCC), a novel technique for six-dimensional (6D) ionization cooling of muon beams, has shown considerable promise based on analytic and simulation studies. However, the implementation of this revolutionary method of muon cooling requires new techniques for the integration of hydrogen-pressurized, high-power RF cavities into the low-temperature superconducting magnets of the HCC. We present the progress toward a conceptual design for the integration of 805 MHz RF cavities into a 10 T Nb{sub 3}Sn based HCC test section. We include discussions on the pressure and thermal barriers needed within the cryostat to maintain operation of the magnet at 4.2 K while operating the RF and energy absorber at a higher temperature. Additionally, we include progress on the Nb{sub 3}Sn helical solenoid design.

  17. Correlation of Cooling Data from an Air-Cooled Cylinder and Several Multicylinder Engines

    Science.gov (United States)

    Pinkel, Benjamin; Ellerbrock, Herman H , Jr

    1940-01-01

    The theory of engine-cylinder cooling developed in a previous report was further substantiated by data obtained on a cylinder from a Wright r-1820-g engine. Equations are presented for the average head and barrel temperatures of this cylinder as functions of the engine and the cooling conditions. These equations are utilized to calculate the variation in cylinder temperature with altitude for level flight and climb. A method is presented for correlating average head and barrel temperatures and temperatures at individual points on the head and the barrel obtained on the test stand and in flight. The method is applied to the correlation and the comparison of data obtained on a number of service engines. Data are presented showing the variation of cylinder temperature with time when the power and the cooling pressure drop are suddenly changed.

  18. Helical muon beam cooling channel engineering design

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Rolland [Muons, Inc., Batavia, IL (United States)

    2015-08-07

    The Helical Cooling Channel (HCC) achieves effective ionization cooling of the six-dimensional (6d) phase space of a muon beam by means of a series of 21st century inventions. In the HCC, hydrogen-pressurized RF cavities enable high RF gradients in strong external magnetic fields. The theory of the HCC, which requires a magnetic field with solenoid, helical dipole, and helical quadrupole components, demonstrates that dispersion in the gaseous hydrogen energy absorber provides effective emittance exchange to enable longitudinal ionization cooling. The 10-year development of a practical implementation of a muon-beam cooling device has involved a series of technical innovations and experiments that imply that an HCC of less than 300 m length can cool the 6d emittance of a muon beam by six orders of magnitude. We describe the design and construction plans for a prototype HCC module based on oxygen-doped hydrogen-pressurized RF cavities that are loaded with dielectric, fed by magnetrons, and operate in a superconducting helical solenoid magnet. The first phase of this project saw the development of a conceptual design for the integration of 805 MHz RF cavities into a 10 T Nb3Sn based HS test section. Two very novel ideas are required to realize the design. The first idea is the use of dielectric inserts in the RF cavities to make them smaller for a given frequency so that the cavities and associated plumbing easily fit inside the magnet cryostat. Calculations indicate that heat loads will be tolerable, while RF breakdown of the dielectric inserts will be suppressed by the pressurized hydrogen gas. The second new idea is the use of a multi-layer Nb3Sn helical solenoid. The technology demonstrations for the two aforementioned key components of a 10T, 805 MHz HCC were begun in this project. The work load in the Fermilab Technical Division made it difficult to test a multi-layer Nb3Sn solenoid as originally planned. Instead, a complementary project was approved by the DOE

  19. Helical muon beam cooling channel engineering design

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Rolland [Muons, Inc., Batavia, IL (United States)

    2015-08-07

    The Helical Cooling Channel (HCC) achieves effective ionization cooling of the six-dimensional (6d) phase space of a muon beam by means of a series of 21st century inventions. In the HCC, hydrogen-pressurized RF cavities enable high RF gradients in strong external magnetic fields. The theory of the HCC, which requires a magnetic field with solenoid, helical dipole, and helical quadrupole components, demonstrates that dispersion in the gaseous hydrogen energy absorber provides effective emittance exchange to enable longitudinal ionization cooling. The 10-year development of a practical implementation of a muon-beam cooling device has involved a series of technical innovations and experiments that imply that an HCC of less than 300 m length can cool the 6d emittance of a muon beam by six orders of magnitude. We describe the design and construction plans for a prototype HCC module based on oxygen-doped hydrogen-pressurized RF cavities that are loaded with dielectric, fed by magnetrons, and operate in a superconducting helical solenoid magnet. The first phase of this project saw the development of a conceptual design for the integration of 805 MHz RF cavities into a 10 T Nb3Sn-based HS test section. Two very novel ideas are required to realize the design. The first idea is the use of dielectric inserts in the RF cavities to make them smaller for a given frequency so that the cavities and associated plumbing easily fit inside the magnet cryostat. Calculations indicate that heat loads will be tolerable, while RF breakdown of the dielectric inserts will be suppressed by the pressurized hydrogen gas. The second new idea is the use of a multi-layer Nb3Sn helical solenoid. The technology demonstrations for the two aforementioned key components of a 10T, 805 MHz HCC were begun in this project. The work load in the Fermilab Technical Division made it difficult to test a multi-layer Nb3Sn solenoid as originally planned. Instead, a complementary

  20. DNA base excision repair nanosystem engineering: model development.

    Science.gov (United States)

    Sokhansanj, B A

    2005-01-01

    DNA base damage results from a combination of endogenous sources, (normal metabolism, increased metabolism due to obesity, stress from diseases such as arthritis and diabetes, and ischemia) and the environment (ingested toxins, ionizing radiation, etc.). If unrepaired DNA base damage can lead to diminished cell function, and potentially diseases and eventually mutations that lead to cancer. Sophisticated DNA repair mechanisms have evolved in all living cells to preserve the integrity of inherited genetic information and transcriptional control. Understanding a system like DNA repair is greatly enhanced by using engineering methods, in particular modeling interactions and using predictive simulation to analyze the impact of perturbations. We describe the use of such a "nanosystem engineering" approach to analyze the DNA base excision repair pathway in human cells, and use simulation to predict the impact of varying enzyme concentration on DNA repair capacity.

  1. Manipulating DNA repair for improved genetic engineering in Aspergillus

    DEFF Research Database (Denmark)

    Nødvig, Christina Spuur

    engineering strategies. Chapter 1 gives an introduction to the genus Aspergillus and some of the tools relevant to fungal genetic engineering. It also contains a short introduction to DNA repair and its interplay with gene targeting and finally an overview over the different genome editing technologies......Aspergillus is a genus of filamentous fungi, which members includes industrial producers of enzymes, organic acids and secondary metabolites, important pathogens and a model organism. As such no matter the specific area of interest there are many reasons to perform genetic engineering, whether...... it is metabolic engineering to create better performing cell factory, elucidating pathways to study secondary metabolism etc. In this thesis, the main focus is on different ways to manipulate DNA repair for optimizing gene targeting, ultimately improving the methods available for faster and better genetic...

  2. Lubrication System. Teacher's Guide. Small Engine Repair Series. First Edition.

    Science.gov (United States)

    Hill, Pamela

    This teacher's guide accompanies three student manuals and together with them comprises an instructional package on the lubrication system in the Small Engine Repair Series for handicapped/special needs students. The first section, "Notes to the Instructor," covers equipment needs, preparation before teaching the instructional package,…

  3. Repair of sciatic nerve defects using tissue engineered nerves*

    Institute of Scientific and Technical Information of China (English)

    Caishun Zhang; Gang Lv

    2013-01-01

    In this study, we constructed tissue-engineered nerves with acel ular nerve al ografts in Sprague-Dawley rats, which were prepared using chemical detergents-enzymatic digestion and mechanical methods, in combination with bone marrow mesenchymal stem cel s of Wistar rats cultured in vitro, to repair 15 mm sciatic bone defects in Wistar rats. At postoperative 12 weeks, electrophysiological detection results showed that the conduction velocity of regenerated nerve after repair with tis-sue-engineered nerves was similar to that after autologous nerve grafting, and was higher than that after repair with acel ular nerve al ografts. Immunohistochemical staining revealed that motor endplates with acetylcholinesterase-positive nerve fibers were orderly arranged in the middle and superior parts of the gastrocnemius muscle;regenerated nerve tracts and sprouted branches were connected with motor endplates, as shown by acetylcholinesterase histochemistry combined with silver staining. The wet weight ratio of the tibialis anterior muscle at the affected contralateral hind limb was similar to the sciatic nerve after repair with autologous nerve grafts, and higher than that after repair with acel ular nerve al ografts. The hind limb motor function at the affected side was significantly improved, indicating that acel ular nerve al ografts combined with bone marrow me-senchymal stem cel bridging could promote functional recovery of rats with sciatic nerve defects.

  4. Ambient air cooling arrangement having a pre-swirler for gas turbine engine blade cooling

    Science.gov (United States)

    Lee, Ching-Pang; Tham, Kok-Mun; Schroeder, Eric; Meeroff, Jamie; Miller, Jr., Samuel R; Marra, John J

    2015-01-06

    A gas turbine engine including: an ambient-air cooling circuit (10) having a cooling channel (26) disposed in a turbine blade (22) and in fluid communication with a source (12) of ambient air: and an pre-swirler (18), the pre-swirler having: an inner shroud (38); an outer shroud (56); and a plurality of guide vanes (42), each spanning from the inner shroud to the outer shroud. Circumferentially adjacent guide vanes (46, 48) define respective nozzles (44) there between. Forces created by a rotation of the turbine blade motivate ambient air through the cooling circuit. The pre-swirler is configured to impart swirl to ambient air drawn through the nozzles and to direct the swirled ambient air toward a base of the turbine blade. The end walls (50, 54) of the pre-swirler may be contoured.

  5. Engineering the cooling and ventilation for the LHC

    CERN Document Server

    Wilhelmsson, M

    2003-01-01

    Early in the LHC-project, a decision was made to complete in-house, as much of the engineering for the new cooling and ventilation systems as was practicable. This is achieved using the competence of resident (CERN staff) engineers for the studies, project management, on-site installation, supervision, etc. The documentation has however, been compiled using the format of tender drawings in the technical office by industrial service personnel. This model, adopted by the Cooling and Ventilation (CV) group is attractive from the viewpoint of conservation of “know-how” within CERN. The main difficulty is however, to be able to absorb such an important project within available manpower. This paper will revisit the arguments behind this method as well as summarize the results to date. Finally, the author will outline other methods (followed by other groups within the project), for a comparison with the model chosen by ST/CV.

  6. AC maintenance and repair manual for diesel engines

    CERN Document Server

    Pallas, Jean-Luc

    2013-01-01

    The aim of this book with its detailed step-by-step colour photographs and diagrams, is to enable every owner to fix their diesel engine with ease. Troubleshooting tables help diagnose potential problems, and there is advice on regular maintenance and winterising and repair. Jean-Luc Pallas's enthusiasm for passing on his knowledge, as well as his clear explanations, precise advice and step-by-step instructions make this a unique book.

  7. Heat Reduction FromIc Engine By Using Al2o3Nanofluid In Engine Cooling System

    OpenAIRE

    Vikas Sharma; R.Nirmal Kumar; K.Thamilarasan; G. Vijay Bhaskar; Bhavesh Devra

    2016-01-01

    Cooling system plays important roles to control the temperature of car‟s engine. One of the important elements in the car cooling system is cooling fluid. The usage of wrong cooling fluid can give negatives impact to the car‟s engine and shorten engine life. An efficient cooling system can prevent engine from overheating and assists the vehicle running at its optimal performance. With the development of new technology in the fields of „nano-materials‟ and „nano-fluids‟, it seems v...

  8. Engineered Cooling Process for High Strength Ductile Iron Castings

    Science.gov (United States)

    Lekakh, Simon N.; Mikhailov, Anthony; Kramer, Joseph

    Professor Stefanescu contributed fundamentally to the science of solidification and microstructural evolutions in ductile irons. In this article, the possibility of development of high strength ductile iron by applying an engineered cooling process after casting early shake out from the sand mold was explored. The structures in industrial ductile iron were experimentally simulated using a computer controlled heating/cooling device. CFD modeling was used for process simulation and an experimental bench scale system was developed. The process concept was experimentally verified by producing cast plates with 25 mm wall thickness. The tensile strength was increased from 550 MPa to 1000 MPa in as-cast condition without the need for alloying and heat treatment. The possible practical applications were discussed.

  9. Repair of osteochondral defects with allogeneic tissue engineered cartilage implants.

    Science.gov (United States)

    Schreiber, R E; Ilten-Kirby, B M; Dunkelman, N S; Symons, K T; Rekettye, L M; Willoughby, J; Ratcliffe, A

    1999-10-01

    The objective of this study was to evaluate the effect of allogeneic tissue engineered cartilage implants on healing of osteochondral defects. Rabbit chondrocytes were cultured in monolayer, then seeded onto biodegradable, three-dimensional polyglycolic acid meshes. Cartilage constructs were cultured hydrodynamically to yield tissue with relatively more (mature) or less (immature) hyalinelike cartilage, as compared with adult rabbit articular cartilage. Osteochondral defects in the patellar grooves of both stifle joints either were left untreated or implanted with allogeneic tissue engineered cartilage. Histologic samples from in and around the defect sites were examined 3, 6, 9, and 12, and 24 months after surgery. By 9 months after surgery, defects sites treated with cartilage implants contained significantly greater amounts of hyalinelike cartilage with high levels of proteoglycan, and had a smooth, nonfibrillated articular surface as compared to untreated defects. In contrast, the repair tissue formed in untreated defects had fibrillated articular surfaces, significant amounts of fibrocartilage, and negligible proteoglycan. These differences between treated and untreated defects persisted through 24 months after surgery. The results of this study suggest that the treatment of osteochondral lesions with allogenic tissue engineered cartilage implants may lead to superior repair tissue than that found in untreated osteochondral lesions.

  10. Transpiring Cooling of a Scram-Jet Engine Combustion Chamber

    Science.gov (United States)

    Choi, Sang H.; Scotti, Stephen J.; Song, Kyo D.; Ries,Heidi

    1997-01-01

    The peak cold-wall heating rate generated in a combustion chamber of a scram-jet engine can exceed 2000 Btu/sq ft sec (approx. 2344 W/sq cm). Therefore, a very effective heat dissipation mechanism is required to sustain such a high heating load. This research focused on the transpiration cooling mechanism that appears to be a promising approach to remove a large amount of heat from the engine wall. The transpiration cooling mechanism has two aspects. First, initial computations suggest that there is a reduction, as much as 75%, in the heat flux incident on the combustion chamber wall due to the transpirant modifying the combustor boundary layer. Secondly, the heat reaching the combustor wall is removed from the structure in a very effective manner by the transpirant. It is the second of these two mechanisms that is investigated experimentally in the subject paper. A transpiration cooling experiment using a radiant heating method, that provided a heat flux as high as 200 Btu/sq ft sec ( approx. 234 W/sq cm) on the surface of a specimen, was performed. The experiment utilized an arc-lamp facility (60-kW radiant power output) to provide a uniform heat flux to a test specimen. For safety reasons, helium gas was used as the transpirant in the experiments. The specimens were 1.9-cm diameter sintered, powdered-stainless-steel tubes of various porosities and a 2.54cm square tube with perforated multi-layered walls. A 15-cm portion of each specimen was heated. The cooling effectivenes and efficiencies by transpiration for each specimen were obtained using the experimental results. During the testing, various test specimens displayed a choking phenomenon in which the transpirant flow was limited as the heat flux was increased. The paper includes a preliminary analysis of the transpiration cooling mechanism and a scaling conversion study that translates the results from helium tests into the case when a hydrogen medium is used.

  11. Improved repair of bone defects with prevascularized tissue-engineered bones constructed in a perfusion bioreactor.

    Science.gov (United States)

    Li, De-Qiang; Li, Ming; Liu, Pei-Lai; Zhang, Yuan-Kai; Lu, Jian-Xi; Li, Jian-Min

    2014-10-01

    Vascularization of tissue-engineered bones is critical to achieving satisfactory repair of bone defects. The authors investigated the use of prevascularized tissue-engineered bone for repairing bone defects. The new bone was greater in the prevascularized group than in the non-vascularized group, indicating that prevascularized tissue-engineered bone improves the repair of bone defects. [Orthopedics. 2014; 37(10):685-690.].

  12. Preliminary engineering design of sodium-cooled CANDLE core

    Science.gov (United States)

    Takaki, Naoyuki; Namekawa, Azuma; Yoda, Tomoyuki; Mizutani, Akihiko; Sekimoto, Hiroshi

    2012-06-01

    The CANDLE burning process is characterized by the autonomous shifting of burning region with constant reactivity and constant spacial power distribution. Evaluations of such critical burning process by using widely used neutron diffusion and burning codes under some realistic engineering constraints are valuable to confirm the technical feasibility of the CANDLE concept and to put the idea into concrete core design. In the first part of this paper, it is discussed that whether the sustainable and stable CANDLE burning process can be reproduced even by using conventional core analysis tools such as SLAROM and CITATION-FBR. As a result, it is certainly possible to demonstrate it if the proper core configuration and initial fuel composition required as CANDLE core are applied to the analysis. In the latter part, an example of a concrete image of sodium cooled, metal fuel, 2000MWt rating CANDLE core has been presented by assuming an emerging inevitable technology of recladding. The core satisfies engineering design criteria including cladding temperature, pressure drop, linear heat rate, and cumulative damage fraction (CDF) of cladding, fast neutron fluence and sodium void reactivity which are defined in the Japanese FBR design project. It can be concluded that it is feasible to design CADLE core by using conventional codes while satisfying some realistic engineering design constraints assuming that recladding at certain time interval is technically feasible.

  13. Simulation of Laser Cooling and Trapping in Engineering Applications

    Science.gov (United States)

    Ramirez-Serrano, Jaime; Kohel, James; Thompson, Robert; Yu, Nan; Lunblad, Nathan

    2005-01-01

    An advanced computer code is undergoing development for numerically simulating laser cooling and trapping of large numbers of atoms. The code is expected to be useful in practical engineering applications and to contribute to understanding of the roles that light, atomic collisions, background pressure, and numbers of particles play in experiments using laser-cooled and -trapped atoms. The code is based on semiclassical theories of the forces exerted on atoms by magnetic and optical fields. Whereas computer codes developed previously for the same purpose account for only a few physical mechanisms, this code incorporates many more physical mechanisms (including atomic collisions, sub-Doppler cooling mechanisms, Stark and Zeeman energy shifts, gravitation, and evanescent-wave phenomena) that affect laser-matter interactions and the cooling of atoms to submillikelvin temperatures. Moreover, whereas the prior codes can simulate the interactions of at most a few atoms with a resonant light field, the number of atoms that can be included in a simulation by the present code is limited only by computer memory. Hence, the present code represents more nearly completely the complex physics involved when using laser-cooled and -trapped atoms in engineering applications. Another advantage that the code incorporates is the possibility to analyze the interaction between cold atoms of different atomic number. Some properties that cold atoms of different atomic species have, like cross sections and the particular excited states they can occupy when interacting with each other and light fields, play important roles not yet completely understood in the new experiments that are under way in laboratories worldwide to form ultracold molecules. Other research efforts use cold atoms as holders of quantum information, and more recent developments in cavity quantum electrodynamics also use ultracold atoms to explore and expand new information-technology ideas. These experiments give a hint

  14. Thermal modeling in an engine cooling system to control coolant flow for fuel consumption improvement

    Science.gov (United States)

    Park, Sangki; Woo, Seungchul; Kim, Minho; Lee, Kihyung

    2016-09-01

    The design and evaluation of engine cooling and lubrication systems is generally based on real vehicle tests. Our goal here was to establish an engine heat balance model based on mathematical and interpretive analysis of each element of a passenger diesel engine cooling system using a 1-D numerical model. The purpose of this model is to determine ways of optimizing the cooling and lubrication components of an engine and then to apply these methods to actual cooling and lubrication systems of engines that will be developed in the future. Our model was operated under the New European Driving Cycle (NEDC) mode conditions, which represent the fuel economy evaluation mode in Europe. The flow rate of the cooling system was controlled using a control valve. Our results showed that the fuel efficiency was improved by as much as 1.23 %, cooling loss by 1.35 %, and friction loss by 2.21 % throughout NEDC modes by modification of control conditions.

  15. Self-Repairing of Chinese Science and Engineering Majors in Oral English

    Science.gov (United States)

    Wang, Weiwei; Xu, Xiaoqin

    2015-01-01

    This study employs corpus analytical tools to carry out a systematic study on Chinese Science and Engineering Majors' (SEMs') use of self-repair in their oral English. The study aims to find out the overall feature of using self-repair by SEMs and to see if there exists statistically significant difference of using self-repair across different…

  16. Drag and Cooling with Various Forms of Cowling for a "Whirlwind" Radial Air-Cooled Engine I

    Science.gov (United States)

    Weick, Fred E

    1930-01-01

    This report presents the results of an investigation undertaken in the 20-foot Propeller Research Tunnel at Langley Field on the cowling of radial air-cooled engines. A portion of the investigation has been completed, in which several forms and degrees of cowling were tested on Wright "Whirlwind" J-5 engine mounted in the nose of a cabin fuselage. The cowlings varied from the one extreme of an entirely exposed engine to the other in which the engine was entirely inclosed. Cooling tests were made and each cowling modified, if necessary, until the engine cooled approximately as satisfactorily as when it was entirely exposed. Drag tests were then made with each form of cowling, and the effect of the cowling on the propulsive efficiency determined with a metal propeller. The propulsive efficiency was found to be practically the same with all forms of cowling. The drag of the cabin fuselage with uncowled engine was found to be more than three times as great as the drag of the fuselage with engine removed and nose rounded. The conventional forms of cowling, in which at least the tops of the cylinder heads and valve gear are exposed, reduce the drag somewhat, but the cowling entirely covering the engine reduces it 2.6 times as much as the best conventional one. The decrease in drag due to the use of spinners proved to be almost negligible. The use of the cowling completely covering the engine seems entirely practical as regards both cooling and maintenance under service conditions. It must be carefully designed, however, to cool properly. With cabin fuselages its use should result in a substantial increase in high speed over that obtained with present forms of cowling on engines similar in contour to the J-5. (author)

  17. Fuel Economy Opportunities for Internal COmbustion Engines by Means of Oil—Cooling

    Institute of Scientific and Technical Information of China (English)

    C.F.Ma; J.C.Li; 等

    1997-01-01

    Comparative experiments of oil and water -cooling were performed on a 4-cylinder automotive gasoline engine and a single-cylinder direct injction Diesel engine.Measurements were made to investigate the variation of fuel consumption,combustor wall temperature and engine emissions(HC,CO,NOx and smoke)with two cooling media at steady-state conditions.Significant improvement of fuel econmy was found mainly at partial load conditions with oil-cooling in comparison with the baseline water-cooling both for the two engines.The experimental results also showed general trend of reduction in engine emissions using oil as the coolant,Measurements of wall temperature demonstrated that oil-cooling resulted in considerable increase of the combustor wall temperature and reduce of warm-up period in starting process.For automotive gasoline engine,road tests indicated the same trend of fuel economy improvement with oil-cooling.The performance of the automotive oil-cooled engine was further improved by internal cooling with water or methanol injection.

  18. Fuel economy opportunities for internal combustion engines by means of oil-cooling

    Science.gov (United States)

    Ma, C. F.; Li, J. C.; Qin, W. X.; Wei, Z. Y.; Chen, J.

    1997-06-01

    Comparative experiments of oil and water-cooling were performed on a 4-cylinder automotive gasoline engine and a single-cylinder direct injection Diesel engine. Measurements were made to investigate the variation of fuel consumption, combustor wall temperature and engine emissions (HC, CO, NOx and smoke) with two cooling media at steady-state conditions. Significant improvement of fuel economy was found mainly at partial load conditions with oil-cooling in comparison with the baseline water-cooling both for the two engines. The experimental results also showed general trend of reduction in engine emissions using oil as the coolant. Measurements of wall temperature demonstrated that oil-cooling resulted in considerable increase of the combustor wall temperature and reduce of warm-up period in starting process. For automotive gasoline engine, road tests indicated the same trend of fuel economy improvement with oil-cooling. The performance of the automotive oil-cooled engine was further improved by internal cooling with water or methanol injection.

  19. Variable cooling circuit for thermoelectric generator and engine and method of control

    Science.gov (United States)

    Prior, Gregory P

    2012-10-30

    An apparatus is provided that includes an engine, an exhaust system, and a thermoelectric generator (TEG) operatively connected to the exhaust system and configured to allow exhaust gas flow therethrough. A first radiator is operatively connected to the engine. An openable and closable engine valve is configured to open to permit coolant to circulate through the engine and the first radiator when coolant temperature is greater than a predetermined minimum coolant temperature. A first and a second valve are controllable to route cooling fluid from the TEG to the engine through coolant passages under a first set of operating conditions to establish a first cooling circuit, and from the TEG to a second radiator through at least some other coolant passages under a second set of operating conditions to establish a second cooling circuit. A method of controlling a cooling circuit is also provided.

  20. Turbine Blade Cooling System Optimization

    OpenAIRE

    GIRARDEAU, Julian; PAILHES, Jérôme; SEBASTIAN, Patrick; PARDO, Frédéric; Nadeau, Jean-Pierre

    2013-01-01

    The authors wish to thank turbine designers from TURBOMECA SAFRAN Group.; International audience; Designing high performance cooling systems suitable for preserving the service lifetime of nozzle guide vanes of turboshaft engines leads to significant aerodynamic losses. These losses jeopardize the performance of the whole engine. In the same time, a low efficiency cooling system may affect the costs of maintenance repair and overhaul of the engine as component life decreases. Consequently, de...

  1. The Effects of Cylinder Head Gasket Opening on Engine Temperature Distribution for a Water-Cooled Engine

    Science.gov (United States)

    Jang, J. Y.; Chi, G. X.

    2017-02-01

    In a liquid-cooled engine, coolant is pumped throughout the water jacket of the engine, drawing heat from the cylinder head, pistons, combustion chambers, cylinder walls, and valves, etc. If the engine temperature is too high or too low, various problems will occur. These include overheating of the lubricating oil and engine parts, excessive stresses between engine parts, loss of power, incomplete burning of fuel, etc. Thus, the engine should be maintained at the proper operating temperature. This study investigated the effects of different cylinder head gasket opening on the engine temperature distributions in a water-cooled motorcycle engine. The numerical predictions for the temperature distribution are in good agreement with the experimental data within 20%.

  2. Heat Reduction FromIc Engine By Using Al2o3Nanofluid In Engine Cooling System

    Directory of Open Access Journals (Sweden)

    Vikas Sharma

    2016-08-01

    Full Text Available Cooling system plays important roles to control the temperature of car‟s engine. One of the important elements in the car cooling system is cooling fluid. The usage of wrong cooling fluid can give negatives impact to the car‟s engine and shorten engine life. An efficient cooling system can prevent engine from overheating and assists the vehicle running at its optimal performance. With the development of new technology in the fields of „nano-materials‟ and „nano-fluids‟, it seems very promising to use this technology as a coolant in the internal combustion engines. In this study, a nano-fluid (Al2O3-Water/Ethylene Glycol (EG is used as an engine coolant along with an optimized heat exchanger to reduce the warm-up timing. The effect of nano-fluid concentration is considered here by using their corresponding governing equations, such as momentum and energy. The engine coolant thermal behaviour calculation is carried out based on the lumped method. The obtained results indicated that using different percentage of nano-fluid mixtures (by volume, such as Al2O3-Water/EG as engine coolant enhances the heat transfer coefficient and reduces the warm-up timing which, in turn, results in reduced emissions and fuel consumption.

  3. Application of Microstructure Engineering in Steel Coil Cooling Process

    Institute of Scientific and Technical Information of China (English)

    LIU Zheng-dong; D Q Jin; I V Samarasekera; J K Brimacombe

    2005-01-01

    The coil cooling and its role in a hot strip mill were reviewed.A mathematical model was developed to describe and analyze the thermal history and its impact on precipitation phenomena during coil cooling for plain car bon,HSLA-V and HSLA-Nb steels.The predicted result of the thermal model was compared with that measured from industrial coil.The effect of cooling condition and coil dimension on the thermal history and final mechanical properties of the steel strip was examined.The coiling temperature and cooling rate have crucial influence on the precipitation strengthening.

  4. District cooling engineering & design program. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    1994-03-01

    Phoenix, Arizona is located in the Sonoran desert. Daytime temperatures typically rise to over 100 F during the three summer months. Average and peak temperatures have tended to rise over recent decades. This is generally attributed to what is known as the heat island effect, due to an increase in heat absorbing concrete and a decrease in irrigated farmland in the area. Phoenix is the eighth largest city in the US with a population of just over one million (1,000,000). The metropolitan area is one of the fastest growing in the nation. Over the last ten years its population has increased by over 40%. It is not an exaggeration to say the general availability of refrigerated air conditioning, both for buildings and automobiles has been an important factor enabling growth. The cost of operating public buildings has risen significantly in the last decade. In fiscal year 92/93 the City of Phoenix had energy expenses of over thirty four million dollars ($34,000,000). Because the City was planning a major new construction project, a new high-rise City Hall, it was decided to study and then optimize the design and selection of building systems to minimize long term owning and operating costs. The City Hall was to be constructed in downtown Phoenix. Phoenix presently owns other buildings in the area. A number of large cooling systems serving groups of buildings are currently operating in the Phoenix area. The City requested that the design consultants analyze the available options and present recommendations to the City`s engineering staff.

  5. Cooling system in a rotary piston internal combustion engine. Kuehlsystem einer Rotationskolbenbrennkraftmaschine

    Energy Technology Data Exchange (ETDEWEB)

    Eiermann, D.; Nuber, R.

    1991-05-23

    Cooling system of a trochoid-type rotary piston internal combustion engine with a liquid-cooled casing. First the coolant is conducted isochronically and in parallel through cooling chambers of the jacket and a side part of the casing from where it is transported by a cooling pump through the cooling chambers of the other side part, on past a thermostat and into a cooler positioned on this other side part. The cooler consists of a parallel connected pipe bundle whose finned pipes follow the radial outer contours of the casing of the machine. From the cooler the coolant is conducted back into the cooling chambers of the first side part and the jacket. A blower fitted on the eccentric shaft of the internal combustion engine inside the cooler takes in fresh air axially and discharges it radially through the finned pipes.

  6. Laser Engineered Net Shape (LENS) Technology for the Repair of Ni-Base Superalloy Turbine Components

    Science.gov (United States)

    Liu, Dejian; Lippold, John C.; Li, Jia; Rohklin, Stan R.; Vollbrecht, Justin; Grylls, Richard

    2014-09-01

    The capability of the laser engineered net shape (LENS) process was evaluated for the repair of casting defects and improperly machined holes in gas turbine engine components. Various repair geometries, including indentations, grooves, and through-holes, were used to simulate the actual repair of casting defects and holes in two materials: Alloy 718 and Waspaloy. The influence of LENS parameters, including laser energy density, laser scanning speed, and deposition pattern, on the repair of these defects and holes was studied. Laser surface remelting of the substrate prior to repair was used to remove machining defects and prevent heat-affected zone (HAZ) liquation cracking. Ultrasonic nondestructive evaluation techniques were used as a possible approach for detecting lack-of-fusion in repairs. Overall, Alloy 718 exhibited excellent repair weldability, with essentially no defects except for some minor porosity in repairs representative of deep through-holes and simulated large area casting defects. In contrast, cracking was initially observed during simulated repair of Waspaloy. Both solidification cracking and HAZ liquation cracking were observed in the repairs, especially under conditions of high heat input (high laser power and/or low scanning speed). For Waspaloy, the degree of cracking was significantly reduced and, in most cases, completely eliminated by the combination of low laser energy density and relatively high laser scanning speeds. It was found that through-hole repairs of Waspaloy made using a fine powder size exhibited excellent repair weldability and were crack-free relative to repairs using coarser powder. Simulated deep (7.4 mm) blind-hole repairs, representative of an actual Waspaloy combustor case, were successfully produced by the combination use of fine powder and relatively high laser scanning speeds.

  7. Evaluation of histological scoring systems for tissue-engineered, repaired and osteoarthritic cartilage

    NARCIS (Netherlands)

    Rutgers, M.; van Pelt, M.J.; Dhert, W.J.A.; Creemers, L.B.; Saris, D.B.F.

    2010-01-01

    Osteoarthritis and Cartilage Volume 18, Issue 1, January 2010, Pages 12-23 -------------------------------------------------------------------------------- Review Evaluation of histological scoring systems for tissue-engineered, repaired and osteoarthritic cartilage M. Rutgers†, M.J.P. van Pelt†, W.

  8. Evaluation of histological scoring systems for tissue-engineered, repaired and osteoarthritic cartilage

    NARCIS (Netherlands)

    Rutgers, M.; van Pelt, M.J.; Dhert, W.J.A.; Creemers, L.B.; Saris, D.B.F.

    2010-01-01

    Osteoarthritis and Cartilage Volume 18, Issue 1, January 2010, Pages 12-23 -------------------------------------------------------------------------------- Review Evaluation of histological scoring systems for tissue-engineered, repaired and osteoarthritic cartilage M. Rutgers†, M.J.P. van Pelt†,

  9. Study of fuel consumption and cooling system in low heat rejection turbocharged diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Taymaz, I.; Gur, M.; Cally, I.; Mimaroglu, A.

    1998-07-01

    In a conventional internal combustion engine, approximately one-third of total fuel input energy is converted to useful work. Since the working gas in a practical engine cycle is not exhausted at ambient temperature, a major part of the energy is lost with the exhaust gases. In addition another major part of energy input is rejected in the form of heat via the cooling system. If the energy normally rejected to the coolant could be recovered instead on the crankshaft as useful work, then a substantial improvement in fuel economy would result. At the same time, the cooling water, antifreeze, thermostat, radiator, water pump, cooling fan, and associated hoses and clamps could be eliminated. A new trend in the field of internal combustion engines is to insulate the heat transfer surfaces such as the combustion chamber, cylinder wall, cylinder head, piston and valves by ceramic insulating materials for the improvement of engine performance and elimination of cooling system. In this study, the effect of insulated heat transfer surfaces on direct injected and turbocharged diesel engine fuel consumption and cooling system were investigated. The research engine was a four-stroke, direct injected, six cylinder, turbocharged and intercooled diesel engine. This engine was tested at different speeds and loads conditions without coating. Then, combustion chamber surfaces, cylinder head, valves and piston crown faces was coated with ceramic materials. Ceramic layers were made of CaZrO{sub 3} and MgZrO{sub 3} and plasma coated onto base of the NiCrAl bond coat. The ceramic coated research engine was tested at the same operation conditions as the standard (without coating) engine. The results indicate a reduction in fuel consumption and heat losses to engine cooling system of the ceramic coated engine.

  10. Performance Evaluation of a Software Engineering Tool for Automated Design of Cooling Systems in Injection Moulding

    DEFF Research Database (Denmark)

    Jauregui-Becker, Juan M.; Tosello, Guido; van Houten, Fred J.A.M.

    2013-01-01

    This paper presents a software tool for automating the design of cooling systems for injection moulding and a validation of its performance. Cooling system designs were automatically generated by the proposed software tool and by applying a best practice tool engineering design approach. The two...

  11. Cooling water pump of a rotary piston internal combustion engine. Kuehlwasserpumpe einer Rotationskolbenbrennkraftmaschine

    Energy Technology Data Exchange (ETDEWEB)

    Eiermann, D.; Nuber, R.

    1991-05-23

    Spatial arrangement of a cooling pump of a trochoid-type rotary piston internal combustion engine with a liquid-cooled casing. First the coolant is conducted isochronically and in parallel through cooling chambers of the jacket and a side part into a common hollow space from where it is transported by the cooling pump into the other side part, on past a thermostat to a cooler located in the other side part and back into the cooling loop in the casing. The cooling pump is located in the jacket and its impeller is positioned in a cooling chamber of the other side part. Its shaft can be fitted with a speed controller for the fresh air supply and a lubricating pump.

  12. Lubrication System 1. Check and Change the Engine Oil. Student Manual. Small Engine Repair Series. First Edition.

    Science.gov (United States)

    Hill, Pamela

    This student manual on checking and changing the engine oil is the second of three in an instructional package on the lubrication system in the Small Engine Repair Series for handicapped students. The stated purpose for the booklet is to help students learn what tools and equipment to use and all the steps of the job. Informative material and…

  13. Performance of Engineered Cementitious Composites for Concrete Repairs

    NARCIS (Netherlands)

    Zhou, J.

    2011-01-01

    Background and goals of this thesis The concrete repair, rehabilitation and retrofitting industry grows rapidly, driven by deterioration of, damage to and defects in concrete structures. However, it is well known that to achieve durable concrete repairs is very difficult. The failure of concrete rep

  14. Performance of Engineered Cementitious Composites for Concrete Repairs

    NARCIS (Netherlands)

    Zhou, J.

    2011-01-01

    Background and goals of this thesis The concrete repair, rehabilitation and retrofitting industry grows rapidly, driven by deterioration of, damage to and defects in concrete structures. However, it is well known that to achieve durable concrete repairs is very difficult. The failure of concrete

  15. Performance of Engineered Cementitious Composites for Concrete Repairs

    NARCIS (Netherlands)

    Zhou, J.

    2011-01-01

    Background and goals of this thesis The concrete repair, rehabilitation and retrofitting industry grows rapidly, driven by deterioration of, damage to and defects in concrete structures. However, it is well known that to achieve durable concrete repairs is very difficult. The failure of concrete rep

  16. Cooling system having reduced mass pin fins for components in a gas turbine engine

    Science.gov (United States)

    Lee, Ching-Pang; Jiang, Nan; Marra, John J

    2014-03-11

    A cooling system having one or more pin fins with reduced mass for a gas turbine engine is disclosed. The cooling system may include one or more first surfaces defining at least a portion of the cooling system. The pin fin may extend from the surface defining the cooling system and may have a noncircular cross-section taken generally parallel to the surface and at least part of an outer surface of the cross-section forms at least a quartercircle. A downstream side of the pin fin may have a cavity to reduce mass, thereby creating a more efficient turbine airfoil.

  17. NUMERICAL STUDIES ON HYDROGEN COMBUSTION IN A FILM COOLED CRYOGENIC ROCKET ENGINE

    Directory of Open Access Journals (Sweden)

    ARSHAD A.

    2012-07-01

    Full Text Available Liquid rocket engines have variety of propellant combinations which produces very high specific impulses. It is due to this fact; very high heat fluxes are incident on the combustion chamber and the nozzle walls. In order to deal with these heat fluxes, a wide range of cooling techniques have been employed, out of which a combination of film cooling and regenerative cooling promises to be the most effective one. The present study involves the numerical analysis of combustion in a typical film cooled cryogenic rocket engine thrust chamber considering the combustion of the fuel, heat transfer through the chamber walls and the fluid flow simultaneously. Analysis was done for a typical rocket engine thrust chamber with a single coaxial injector which uses gaseous hydrogen as the fuel and liquid oxygen as the oxidizer.

  18. Influence of the cooling degree upon performances of internal combustion engine

    Science.gov (United States)

    Grǎdinariu, Andrei Cristian; Mihai, Ioan

    2016-12-01

    Up to present, air cooling systems still raise several unsolved problems due to conditions imposed by the environment in terms of temperature and pollution levels. The present paper investigates the impact of the engine cooling degree upon its performances, as important specific power is desired for as low as possible fuel consumption. A technical solution advanced by the authors[1], consists of constructing a bi-flux compressor, which can enhance the engine's performances. The bi-flux axial compressor accomplishes two major functions, that is it cools down the engine and it also turbocharges it. The present paper investigates the temperature changes corresponding to the fresh load, during the use of a bi-flux axial compressor. This compressor is economically simple, compact, and offers an optimal response at low rotational speeds of the engine, when two compression steps are used. The influence of the relative coefficient of air temperature drop upon working agent temperature at the intercooler exit is also investigated in the present work. The variation of the thermal load coefficient by report to the working agent temperature is also investigated during engine cooling. The variation of the average combustion temperature is analyzed in correlation to the thermal load coefficient and the temperatures of the working fluid at its exit from the cooling system. An exergetic analysis was conducted upon the influence of the cooling degree on the motor fluid and the gases resulted from the combustion process.

  19. Small Engine Repair Modules (Workbook) = Reparacion de Motores Pequenos (Guia de Trabajo)

    Science.gov (United States)

    New York State Dept. of Correctional Services, Albany.

    This package contains an English-Language set of task procedure sheets dealing with small-engine repair and a Spanish translation of the same material. Addressed in the individual sections of the manual are the following aspects of engine tune-up, reconditioning, and troubleshooting: servicing air cleaners; cleaning gas tanks, fuel lines, and fuel…

  20. Small Engine Repair Modules (Workbook) = Reparacion de Motores Pequenos (Guia de Trabajo)

    Science.gov (United States)

    New York State Dept. of Correctional Services, Albany.

    This package contains an English-Language set of task procedure sheets dealing with small-engine repair and a Spanish translation of the same material. Addressed in the individual sections of the manual are the following aspects of engine tune-up, reconditioning, and troubleshooting: servicing air cleaners; cleaning gas tanks, fuel lines, and fuel…

  1. Design, Fabrication, and Testing of an Auxiliary Cooling System for Jet Engines

    Science.gov (United States)

    Leamy, Kevin; Griffiths, Jim; Andersen, Paul; Joco, Fidel; Laski, Mark; Balser, Jeffrey (Technical Monitor)

    2001-01-01

    This report summarizes the technical effort of the Active Cooling for Enhanced Performance (ACEP) program sponsored by NASA. It covers the design, fabrication, and integrated systems testing of a jet engine auxiliary cooling system, or turbocooler, that significantly extends the use of conventional jet fuel as a heat sink. The turbocooler is designed to provide subcooled cooling air to the engine exhaust nozzle system or engine hot section. The turbocooler consists of three primary components: (1) a high-temperature air cycle machine driven by engine compressor discharge air, (2) a fuel/ air heat exchanger that transfers energy from the hot air to the fuel and uses a coating to mitigate fuel deposits, and (3) a high-temperature fuel injection system. The details of the turbocooler component designs and results of the integrated systems testing are documented. Industry Version-Data and information deemed subject to Limited Rights restrictions are omitted from this document.

  2. Investigation of Water-spray Cooling of Turbine Blades in a Turbojet Engine

    Science.gov (United States)

    Freche, John C; Stelpflug, William J

    1953-01-01

    An analytical and experimental investigation was made with a J33-A-9 engine to determine the effectiveness of spray cooling as a means of increasing thrust by permitting engine operation at inlet-gas temperatures and speeds above rated. With the assumption of adequate spray cooling at a coolant-to-gas flow ratio of 3 percent, calculations for the sea-level static condition indicated a thrust may be achieved by engine operation at an inlet-gas temperature of 2000 degrees F and an overspeed of 10 percent. Of the water-injection configurations investigated experimentally, those located in the inner ring of the stator diaphragm provided the best cooling at rated engine speed.

  3. 46 CFR 119.425 - Engine exhaust cooling.

    Science.gov (United States)

    2010-10-01

    ... boarding seas; (iv) They are constructed of corrosion resisting material at the hull penetration; and (v... reduction in normal water flow in the exhaust cooling system. (6) A suitable hull strainer must be installed... systems built in accordance with the requirements of American Boat and Yacht Council (ABCY) P-1...

  4. Technology of laser repair welding of nickel superalloy inner flaps of jet engine

    Directory of Open Access Journals (Sweden)

    A. Klimpel

    2011-07-01

    Full Text Available Purpose: of this paper: work out laser welding repair technology of cracked MIG 29 jet engine inner flaps made of cast nickel superalloy ŻS-3DK (ЖС-3ДК, Russian designation.Design/methodology/approach: The study were based on the analysis of laser HPDL powder INCONEL 625 welding of nickel superalloy using wide range of welding parameters to provide highest quality repair welds.Findings: Study of automatic welding technologies GTA, PTA and laser HPDL has shown that just laser welding can provide high quality repair welds. In order to establish the properties of welded joints repair cracks in the inner flap HPDL laser, studied the hardness, mechanical properties and erosive wear resistance.Research limitations/implications: It was found that only laser HPDL welding can provide high quality repair welds.Practical implications: The technology can be applied for repair cracked MIG 29 jet engine inner flaps.Originality/value: Repairing cracked MIG 29 jet engine inner flaps.

  5. Things for You to Know. Fuel System. Student Manual--Introduction. Small Engine Repair Series. First Edition.

    Science.gov (United States)

    Hill, Pamela

    This student manual, part of a small-engine repair series on servicing fuel systems, is designed for use by special needs students in Texas. Information covered in this manual is considered to be the minimum that students need to know about fuel systems in order to get small-engine repair jobs. The manual introduces students to small-engine fuel…

  6. 46 CFR 167.65-70 - Reports of accidents, repairs, and unsafe boilers and machinery by engineers.

    Science.gov (United States)

    2010-10-01

    ... machinery by engineers. 167.65-70 Section 167.65-70 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... of accidents, repairs, and unsafe boilers and machinery by engineers. (a) Before making repairs to a... shall be the duty of all engineers when an accident occurs to the boilers or machinery in their...

  7. PERSPECTIVES OF USING OF EVAPORATIVE COOLING IN REFRIGERATION ENGINEERING

    Directory of Open Access Journals (Sweden)

    Doroshenko A.V.

    2013-08-01

    Full Text Available The concept of creation of multi-stage evaporative coolers of gases and liquids based on multi-channel monoblock polymer structures was developed. The indirect types of coolers in normal and regenerative options are used as the basic elements in them. Natural limit of the cooling in such systems is the dew point of outside air, which significantly enhances the possibilities of the evaporative cooling technology in general, and allows us to solve a number of problems of the refrigeration and air conditioning equipment with a significant reduction of energy consumption for the process. Particular attention is paid to the problem of water vapor recondensation in the transition to multi-stage evaporative coolers. The theory of joint heat and mass transfer in indirect evaporative cooling was examined. The principle of design of individual monoblocks, as well as multi-stage blocks, was developed and recommendations to the design of a new generation of evaporative coolers were made. Preliminary analysis of the possibilities of the evaporative coolers applying to the solution of problems of air conditioning was made.

  8. Efficiency and its bounds for thermal engines at maximum power using Newton's law of cooling.

    Science.gov (United States)

    Yan, H; Guo, Hao

    2012-01-01

    We study a thermal engine model for which Newton's cooling law is obeyed during heat transfer processes. The thermal efficiency and its bounds at maximum output power are derived and discussed. This model, though quite simple, can be applied not only to Carnot engines but also to four other types of engines. For the long thermal contact time limit, new bounds, tighter than what were known before, are obtained. In this case, this model can simulate Otto, Joule-Brayton, Diesel, and Atkinson engines. While in the short contact time limit, which corresponds to the Carnot cycle, the same efficiency bounds as that from Esposito et al. [Phys. Rev. Lett. 105, 150603 (2010)] are derived. In both cases, the thermal efficiency decreases as the ratio between the heat capacities of the working medium during heating and cooling stages increases. This might provide instructions for designing real engines.

  9. Efficiency and its bounds for thermal engines at maximum power using Newton's law of cooling

    Science.gov (United States)

    Yan, H.; Guo, Hao

    2012-01-01

    We study a thermal engine model for which Newton's cooling law is obeyed during heat transfer processes. The thermal efficiency and its bounds at maximum output power are derived and discussed. This model, though quite simple, can be applied not only to Carnot engines but also to four other types of engines. For the long thermal contact time limit, new bounds, tighter than what were known before, are obtained. In this case, this model can simulate Otto, Joule-Brayton, Diesel, and Atkinson engines. While in the short contact time limit, which corresponds to the Carnot cycle, the same efficiency bounds as that from Esposito [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.105.150603 105, 150603 (2010)] are derived. In both cases, the thermal efficiency decreases as the ratio between the heat capacities of the working medium during heating and cooling stages increases. This might provide instructions for designing real engines.

  10. Study on Effects of Diesel Engine Cooling System Parameters on Water Temperature

    Institute of Scientific and Technical Information of China (English)

    骆清国; 冯建涛; 刘国夫; 桂勇

    2011-01-01

    A simulation model for a certain diesel engine cooling system is set up by using GT-COOL. The backwater tem- perature response in different operating conditions is simulated numerically. The effects of single or multiple system parameters on the water temperature are analyzed. The results show that, changing different single parameters, the time taken for the steady backwater temperature is different, but relatively short; and if multiple parameters are changed, the time will be longer. Referred to the thermal balance test, the simulation results are validated and provide a basis for the intelligent con- trol of the cooling system.

  11. Tissue-engineered tendon constructs for rotator cuff repair in sheep.

    Science.gov (United States)

    Novakova, Stoyna S; Mahalingam, Vasudevan D; Florida, Shelby E; Mendias, Christopher L; Allen, Answorth; Arruda, Ellen M; Bedi, Asheesh; Larkin, Lisa M

    2017-06-28

    Current rotator cuff repair commonly involves the use of single or double row suture techniques, and despite successful outcomes, failure rates continue to range from 20 to 95%. Failure to regenerate native biomechanical properties at the enthesis is thought to contribute to failure rates. Thus, the need for technologies that improve structural healing of the enthesis after rotator cuff repair is imperative. To address this issue, our lab has previously demonstrated enthesis regeneration using a tissue-engineered graft approach in a sheep anterior cruciate ligament (ACL) repair model. We hypothesized that our tissue-engineered graft designed for ACL repair also will be effective in rotator cuff repair. The goal of this study was to test the efficacy of our Engineered Tissue Graft for Rotator Cuff (ETG-RC) in a rotator cuff tear model in sheep and compare this novel graft technology to the commonly used double row suture repair technique. Following a 6-month recovery, the grafted and contralateral shoulders were removed, imaged using X-ray, and tested biomechanically. Additionally, the infraspinatus muscle, myotendinous junction, enthesis, and humeral head were preserved for histological analysis of muscle, tendon, and enthesis structure. Our results showed that our ETC-RCs reached 31% of the native tendon tangent modulus, which was a modest, non-significant, 11% increase over that of the suture-only repairs. However, the histological analysis showed the regeneration of a native-like enthesis in the ETG-RC-repaired animals. This advanced structural healing may improve over longer times and may diminish recurrence rates of rotator cuff tears and lead to better clinical outcomes. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  12. Performance Assessment of a Desiccant Cooling System in a CHP Application with an IC Engine

    Energy Technology Data Exchange (ETDEWEB)

    Jalalzadeh-Azar, A. A.; Slayzak, S.; Judkoff, R.; Schaffhauser, T.; DeBlasio, R.

    2005-04-01

    Performance of a desiccant cooling system was evaluated in the context of combined heat and power (CHP). The baseline system incorporated a desiccant dehumidifier, a heat exchanger, an indirect evaporative cooler, and a direct evaporative cooler. The desiccant unit was regenerated through heat recovery from a gas-fired reciprocating internal combustion engine. The system offered sufficient sensible and latent cooling capacities for a wide range of climatic conditions, while allowing influx of outside air in excess of what is typically required for commercial buildings. Energy and water efficiencies of the desiccant cooling system were also evaluated and compared with those of a conventional system. The results of parametric assessments revealed the importance of using a heat exchanger for concurrent desiccant post cooling and regeneration air preheating. These functions resulted in enhancement of both the cooling performance and the thermal efficiency, which are essential for fuel utilization improvement. Two approaches for mixing of the return air and outside air were examined, and their impact on the system cooling performance and thermal efficiency was demonstrated. The scope of the parametric analyses also encompassed the impact of improving the indirect evaporative cooling effectiveness on the overall cooling system performance.

  13. Review and assessment of engineering economic studies of dry cooled electrical generating plants

    Energy Technology Data Exchange (ETDEWEB)

    Fryer, B.C.

    1976-03-01

    The major U.S. studies conducted between 1970 and 1975 on the economics of dry cooled electrical generating plants are reviewed. This review was undertaken to collect, compare, and summarize the approaches, assumptions, and results of several major studies on dry cooling engineering economics, and to evaluate the computer codes associated with these economic studies. From this review it was concluded that adequate detailed evaluation of state-of-the-art dry cooling systems has not been conducted and that comprehensive computer programs capable of such evaluations are not publicly available. Therefore, it is recommended that: a method for determining power production costs of dry cooled plants should be developed which reflects the actual way a utility would interface a dry cooled plant with a utility system to minimize power production costs; a comprehensive detailed evaluation of metal finned tube state-of-the-art dry cooling systems should be conducted to determine if, and where, the costs of dry cooling can be reduced; and advanced dry cooling concepts should be evaluated for potential savings in power production costs. (LCL)

  14. Mechanism Interpretation of the Biological Brain Cooling and Its Inspiration on Bionic Engineering

    Institute of Scientific and Technical Information of China (English)

    Xu Xue; Jing Liu

    2011-01-01

    The brain is one of the most important organs in a biological body which can only work in a relatively stable temperature range. However, many environmental factors in biosphere would cause cerebral temperature fluctuations. To sustain and regulate the brain temperature, many mechanisms of biological brain cooling have been evolved, including Selective Brain Cooling (SBC), cooling through surface water evaporation, respiration, behavior response and using special anatomical appendages. This article is dedicated to present a summarization and systematic interpretation on brain cooling strategies developed in animals by classifying and comparatively analyzing each typical biological brain cooling mechanism from the perspective of bio-heat transfer. Meanwhile, inspirations from such cooling in nature were proposed for developing advanced bionic engineering technologies especially with two focuses on therapeutic hypothermia and computer chip cooling areas. It is expected that many innovations can be achieved along this way to find out new cooling methodologies for a wide variety of industrial applications which will be highly efficient, energy saving, flexible or even intelligent.

  15. Biodegradable Materials for Bone Repair and Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Zeeshan Sheikh

    2015-08-01

    Full Text Available This review discusses and summarizes the recent developments and advances in the use of biodegradable materials for bone repair purposes. The choice between using degradable and non-degradable devices for orthopedic and maxillofacial applications must be carefully weighed. Traditional biodegradable devices for osteosynthesis have been successful in low or mild load bearing applications. However, continuing research and recent developments in the field of material science has resulted in development of biomaterials with improved strength and mechanical properties. For this purpose, biodegradable materials, including polymers, ceramics and magnesium alloys have attracted much attention for osteologic repair and applications. The next generation of biodegradable materials would benefit from recent knowledge gained regarding cell material interactions, with better control of interfacing between the material and the surrounding bone tissue. The next generations of biodegradable materials for bone repair and regeneration applications require better control of interfacing between the material and the surrounding bone tissue. Also, the mechanical properties and degradation/resorption profiles of these materials require further improvement to broaden their use and achieve better clinical results.

  16. Quantum Reservoir Engineering with Laser Cooled Trapped Ions

    Energy Technology Data Exchange (ETDEWEB)

    Poyatos, J.; Cirac, J.I.; Zoller, P. [Institut fuer Theoretische Physik, Universitaet Innsbruck, Technikerstrasse 25, A-6020 Innsbruck (Austria)

    1996-12-01

    We show how to design different couplings between a single ion trapped in a harmonic potential and an environment. The coupling is due to the absorption of a laser photon and subsequent spontaneous emission. The variation of the laser frequencies and intensities allows one to {open_quote}{open_quote}engineer{close_quote}{close_quote} the coupling and select the master equation describing the motion of the ion. {copyright} {ital 1996 The American Physical Society.}

  17. Tissue Engineering for Rotator Cuff Repair: An Evidence-Based Systematic Review

    Directory of Open Access Journals (Sweden)

    Nicola Maffulli

    2012-01-01

    Full Text Available The purpose of this systematic review was to address the treatment of rotator cuff tears by applying tissue engineering approaches to improve tendon healing, specifically platelet rich plasma (PRP augmentation, stem cells, and scaffolds. Our systematic search was performed using the combination of the following terms: “rotator cuff”, “shoulder”, “PRP”, “platelet rich plasma”, “stemcells”, “scaffold”, “growth factors”, and “tissue engineering”. No level I or II studies were found on the use of scaffolds and stem cells for rotator cuff repair. Three studies compared rotator cuff repair with or without PRP augmentation. All authors performed arthroscopic rotator cuff repair with different techniques of suture anchor fixation and different PRP augmentation. The three studies found no difference in clinical rating scales and functional outcomes between PRP and control groups. Only one study showed clinical statistically significant difference between the two groups at the 3-month followup. Any statistically significant difference in the rates of tendon rerupture between the control group and the PRP group was found using the magnetic resonance imaging. The current literature on tissue engineering application for rotator cuff repair is scanty. Comparative studies included in this review suggest that PRP augmented repair of a rotator cuff does not yield improved functional and clinical outcome compared with non-augmented repair at a medium and long-term followup.

  18. Repairing articular cartilage defects with tissue-engineering cartilage in rabbits

    Institute of Scientific and Technical Information of China (English)

    SONG Hong-xing; LI Fo-bao; SHEN Hui-liang; LIAO Wei-ming; LIU Miao; WANG Min; CAO Jun-ling

    2006-01-01

    Objective: To investigate the effect of cancellous bone matrix gelatin (BMG) engineered with allogeneic chondrocytes in repairing articular cartilage defects in rabbits.Methods: Chondrocytes were seeded onto three-dimensional cancellous BMG and cultured in vitro for 12 days to prepare BMG-chondrocyte complexes. Under anesthesia with 2.5% pentobarbital sodium (1 ml/kg body weight), articular cartilage defects were made on the right knee joints of 38 healthy New Zealand white rabbits (regardless of sex, aged 4-5 months and weighing 2.5-3 kg) and the defects were then treated with 2.5 % trypsin.Then BMG-chondrocyte complex (Group A, n=18 ),BMG ( Group B, n=10), and nothing ( Group C, n=10)were implanted into the cartilage defects, respectively. The repairing effects were assessed by macroscopic, histologic,transmission electron microscopic (TEM) observation,immunohistochemical examination and in situ hybridization detection, respectively, at 2, 4, 8, 12 and 24 weeks after operation.Results: Cancellous BMG was degraded within 8 weeks after operation. In Group A, lymphocyte infiltration was observed around the graft. At 24 weeks after operation, the cartilage defects were repaired by cartilage tissues and the articular cartilage and subchondral bone were soundly healed. Proteoglycan and type Ⅱ collagen were detected in the matrix of the repaired tissues by Safranin-O staining and immunohistochemical staining,respectively. In situ hybridization proved gene expression of type Ⅱ collagen in the cytoplasm of chondrocytes in the repaired tissues. TEM observation showed that chondrocytes and cartilage matrix in repaired tissues were almost same as those in the normal articular cartilage. In Group B, the defects were repaired by cartilage-fibrous tissues. In Group C, the defects were repaired only by fibrous tissues.Conclusions : Cancellous BMG can be regarded as the natural cell scaffolds for cartilage tissue engineering.Articular cartilage defects can be repaired by

  19. Tissue engineered devices for ligament repair, replacement and ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-12-29

    Dec 29, 2009 ... School of Biomedical Engineering and Sciences, Virginia Tech, Blacksburg, VA, USA, 24060. E-mail: ...... humans. Immunology Today, 14: 3. ... 558-570. Phelps CJ, Koike C, Vaught TD, Boone J, Wells KD, Chen SH, Ball S,.

  20. Influence of Underhood Flow on Engine Cooling Using 1-D And 3-D Approach

    Directory of Open Access Journals (Sweden)

    Bolehovský Ondřej

    2015-12-01

    Full Text Available This work deals with numerical simulation of complete cooling system of internal combustion engine (GT-SUITE, which also involves the simulation of flow in underhood using the computationally undemanding simulation. A detailed model of the internal combustion engine is extended to a cooling circuit model which is then coupled to a simplified underhood model which is created with the help of GT-COOL application as a 3-D model and afterwards transferred to a 1-D form. The approaches, one using 1-D solution of arrangement of the heat exchangers and the other 3-D approach using the underhood model, were investigated in two steady states corresponding to various vehicle speeds and engine load. These simulations have shown the inappropriateness of 1-D approach when solving the flow in the heat exchangers in the underhood and helped to explore a relatively undemanding method of flow simulation in the underhood, which enables to detect the interaction between the models of the cooling system and the internal combustion engine and the issue of arrangement of the heat exchangers in the underhood.

  1. An Investigation of the Ranger V-770-8 Engine Installation for the Edo XOSE-1 Airplane I : Cooling

    Science.gov (United States)

    Emmons, M. Arnold; Conway, Robert N.

    1945-01-01

    Engine temperature data and cooling correlating analyses of the engine and oil cooler are presented in connection with an investigation of the cowling and cooling of the ranger V-770-8 engine installation in the Edo XOSE-1 airplane. Three types of baffles were installed in the course of the tests: the conventional, the turbulent-flow, and the NACA diffuser baffles. Each of the types was of merit in cooling a different region on the cylinder. Incorporation of the best features of the three types into one baffle, a method which appears to be feasible, would provide improvements in cylinder cooling.

  2. Preliminary Tests of Nose- and Side- Entrance Blower Cooling Systems for Radial Engines, Special Report

    Science.gov (United States)

    Biermann, David; Valentine, E. Floyd

    1939-01-01

    Two cowling systems intended to reduce the drag and improve the low-speed cooling characteristics of conventional radial engine cowlings were tested in model form to determine the practicability of the methods. One cowling included a blower mounted on the rear face of a large propeller spinner which drew cooling air in through side entrance ducts located behind the equivalent engine orifice plate. The air was passed through the equivalent engine orifice plate from rear to front and out through a slot between the spinner and the engine plate. The blower produced substantially all the power necessary to circulate the cooling air in some cases, so the quantity of air flowing was independent of the air speed, Two types of blowers were used, a centrifugal type and one using airfoil blades which forced the air outward from the center of rotation. The other cowling was similar to the conventional N.A.C.A. cowling except for the addition of a large propeller spinner nose. The spinner was provided with a hole in the nose to admit cooling air and blower blades to increase the pressure for cooling at low speeds. The tests show that with both cowling types the basic drag of the nacelle was reduced substantially below that for the N.A.C.A. cowling by virtue of the better nose shape made possible by the spinner . The drag due to the side-entrance ducts was nearly zero when the openings were closed or when the blower was drawing in a certain quantity of air in proportion to the air speed. The drag increased, however, when air mas allowed to spill from the openings. The nose-entrance blower showed considerable promise as a cooling means although the blower tested was relatively inefficient, owing to the fact that the blower compartments evidently were expanded too rapidly under the conditions imposed. by the design.

  3. Lubrication System 2. Service the Crankcase Breather. Student Manual. Small Engine Repair Series. First Edition.

    Science.gov (United States)

    Hill, Pamela

    This student manual on servicing the crankcase breather is the third of three in an instructional package on the lubrication system in the Small Engine Repair Series for handicapped students. The stated purpose for the booklet is to help students learn what tools and equipment to use and all the steps of the job. Informative material and…

  4. Lubrication System. Introduction: Things for You to Know. Student Manual. Small Engine Repair Series. First Edition.

    Science.gov (United States)

    Hill, Pamela

    This student manual introducing the lubrication system is the first of three in an instructional package on the lubrication system in the Small Engine Repair Series for handicapped students. The stated purpose of the booklet is to help students learn about the lubrication system and safe and good work habits. Informative material and diagrams are…

  5. ADJUSTMENT, MAINTENANCE, AND REPAIR OF SMALL GASOLINE ENGINES. AGRICULTURAL MACHINERY--SERVICE OCCUPATIONS, MODULE NUMBER 12.

    Science.gov (United States)

    Ohio State Univ., Columbus. Center for Vocational and Technical Education.

    ONE OF A SERIES DESIGNED TO HELP TEACHERS PREPARE POSTSECONDARY STUDENTS FOR THE AGRICULTURAL MACHINERY SERVICE OCCUPATIONS AS PARTS MEN, MECHANICS, MECHANIC'S HELPERS, OR SERVICE SUPERVISORS, THIS GUIDE AIMS TO DEVELOP STUDENT COMPETENCY IN THE ADJUSTMENT, MAINTENANCE, AND REPAIR OF SMALL GASOLINE ENGINES. IT WAS DEVELOPED BY A NATIONAL TASK…

  6. Efficiency and its bounds for thermal engines at maximum power using Newton's law of cooling

    OpenAIRE

    Yan, H; Guo, H.

    2012-01-01

    We study a thermal engine model for which Newton's cooling law is obeyed during heat transfer processes. The thermal efficiency and its bounds at maximum output power are derived and discussed. This model, though quite simple, can be applied not only to Carnot engines but also to four other types of engines. For the long thermal contact time limit, new bounds, tighter than what were known before, are obtained. In this case, this model can simulate Otto, Joule-Brayton, Diesel, and Atkinson eng...

  7. Modeling and Simulation of Truck Engine Cooling System for Onboard Diagnosis

    Institute of Scientific and Technical Information of China (English)

    朱正礼; 张建武; 包继华

    2004-01-01

    A cooling system model of a selected internal combustion engine has been built for onboard diagnosis. The model uses driving cycle data available within the production Engine Control Module (ECM): vehicle speed, engine speed, and fuel flow rate for the given ambient temperature and pressure, etc. Based on the conservation laws for heat transfer and mass flow process, the mathematical descriptions for the components involved in the cooling circuit are obtained and all the components are integrated into a model on Matlab/Simulink platform. The model can simulate the characteristics of thermostat (e.g. time-lag, hysteresis effect).The changes of coolant temperature, heat transfer flow rate, and pressure at individual component site are also shown.

  8. Adaptive individual-cylinder thermal state control using piston cooling for a GDCI engine

    Energy Technology Data Exchange (ETDEWEB)

    Roth, Gregory T; Husted, Harry L; Sellnau, Mark C

    2015-04-07

    A system for a multi-cylinder compression ignition engine includes a plurality of nozzles, at least one nozzle per cylinder, with each nozzle configured to spray oil onto the bottom side of a piston of the engine to cool that piston. Independent control of the oil spray from the nozzles is provided on a cylinder-by-cylinder basis. A combustion parameter is determined for combustion in each cylinder of the engine, and control of the oil spray onto the piston in that cylinder is based on the value of the combustion parameter for combustion in that cylinder. A method for influencing combustion in a multi-cylinder engine, including determining a combustion parameter for combustion taking place in in a cylinder of the engine and controlling an oil spray targeted onto the bottom of a piston disposed in that cylinder is also presented.

  9. An experimental investigation of liquid methane convection and boiling in rocket engine cooling channels

    Science.gov (United States)

    Trujillo, Abraham Gerardo

    In the past decades, interest in developing hydrocarbon-fueled rocket engines for deep spaceflight missions has continued to grow. In particular, liquid methane (LCH4) has been of interest due to the weight efficiency, storage, and handling advantages it offers over several currently used propellants. Deep space exploration requires reusable, long life rocket engines. Due to the high temperatures reached during combustion, the life of an engine is significantly impacted by the cooling system's efficiency. Regenerative (regen) cooling is presented as a viable alternative to common cooling methods such as film and dump cooling since it provides improved engine efficiency. Due to limited availability of experimental sub-critical liquid methane cooling data for regen engine design, there has been an interest in studying the heat transfer characteristics of the propellant. For this reason, recent experimental studies at the Center for Space Exploration Technology Research (cSETR) at the University of Texas at El Paso (UTEP) have focused on investigating the heat transfer characteristics of sub-critical CH4 flowing through sub-scale cooling channels. To conduct the experiments, the csETR developed a High Heat Flux Test Facility (HHFTF) where all the channels are heated using a conduction-based thermal concentrator. In this study, two smooth channels with cross sectional geometries of 1.8 mm x 4.1 mm and 3.2 mm x 3.2 mm were tested. In addition, three roughened channels all with a 3.2 mm x 3.2 mm square cross section were also tested. For the rectangular smooth channel, Reynolds numbers ranged between 68,000 and 131,000, while the Nusselt numbers were between 40 and 325. For the rough channels, Reynolds numbers ranged from 82,000 to 131,000, and Nusselt numbers were between 65 and 810. Sub-cooled film-boiling phenomena were confirmed for all the channels presented in this work. Film-boiling onset at Critical Heat Flux (CHF) was correlated to a Boiling Number (Bo) of

  10. Genome engineering with TALENs and ZFNs: repair pathways and donor design.

    Science.gov (United States)

    Carroll, Dana; Beumer, Kelly J

    2014-09-01

    Genome engineering with targetable nucleases depends on cellular pathways of DNA repair after target cleavage. Knowledge of how those pathways work, their requirements and their active factors, can guide experimental design and improve outcomes. While many aspects of both homologous recombination (HR) and nonhomologous end joining (NHEJ) are shared by a broad range of cells and organisms, some features are specific to individual situations. This article reviews the influence of repair mechanisms on the results of gene targeting experiments, with an emphasis on lessons learned from experiments with Drosophila.

  11. Engineering and cost comparison of three different all-dry cooling systems

    Energy Technology Data Exchange (ETDEWEB)

    Fryer, B.C.; Braun, D.J.; Braun, D.J.; Faletti, D.W.; Wiles, L.E.

    1976-09-01

    Results of a detailed engineering and cost study of three different all-dry cooling systems to assess the potential for reducing the cost of all-dry cooling for steam electric power plants are described. The three types of cooling systems considered were: state-of-the-art (SOA) dry cooling system; with a conventional surface condenser, and water used to condense the steam is passed through an induced mechanical draft, metal finned tube cooling tower; an advanced dry cooling system (PLASTIC) utilizing heat exchangers made of bare plastic tubes in the cooling tower; and an advanced dry cooling system utilizing ammonia as the coolant (NH/sub 3/). The NH/sub 3/ system differs from the SOA system in that ammonia is substituted for water as the intermediate fluid. Steam from the turbine is condensed by boiling ammonia in a condenser/reboiler; the ammonia vapor is condensed in an induced draft, metal finned tube heat exchanger and returned to the condenser/reboiler. The major conclusions drawn from this study are that: SOA systems offered by vendors are so near optimum in terms of heat exchanger unit geometry and configuration that there is little, if any, cost advantage to be gained by further study of SOA systems using wrap-on or extruded finned tubes other than in the selection of tube materials, materials compatibility, water quality control, or fin manufacturing methods; significant savings (34 percent) in incremental power production costs appear to be obtainable using NH/sub 3/ systems; and considerable savings (22 percent) can also be obtained with PLASTIC systems.

  12. The influence of fuel type on the cooling system heat exchanger parameters in heavy-duty engines

    Science.gov (United States)

    Worsztynowicz, B.

    2016-09-01

    The paper discuses the problem of selection of cooling systems for heavy-duty engines fitted in city buses. Aside from diesel engines, engine manufacturers also have in their portfolio engines fueled with natural gas, whose design is based on that of a conventional diesel engine. Based on the parameters of the engines from this type-series (the same displacement and rated power) an analysis has been performed of the influence of the applied fuel on the heat flows directed to the radiators and charge air coolers, hence, their size and space necessary for their proper installation. A replacement of a diesel engine with a natural gas fueled engine of the same operating parameters results in an increased amount of heat released to the coolant and a reduced heat from the engine charging system. This forces a selection of different heat exchangers that require more space for installation. A universal cooling module for different engines is not an optimal solution.

  13. Implications of Transitioning from De Facto to Engineered Water Reuse for Power Plant Cooling.

    Science.gov (United States)

    Barker, Zachary A; Stillwell, Ashlynn S

    2016-05-17

    Thermoelectric power plants demand large quantities of cooling water, and can use alternative sources like treated wastewater (reclaimed water); however, such alternatives generate many uncertainties. De facto water reuse, or the incidental presence of wastewater effluent in a water source, is common at power plants, representing baseline conditions. In many cases, power plants would retrofit open-loop systems to cooling towers to use reclaimed water. To evaluate the feasibility of reclaimed water use, we compared hydrologic and economic conditions at power plants under three scenarios: quantified de facto reuse, de facto reuse with cooling tower retrofits, and modeled engineered reuse conditions. We created a genetic algorithm to estimate costs and model optimal conditions. To assess power plant performance, we evaluated reliability metrics for thermal variances and generation capacity loss as a function of water temperature. Applying our analysis to the greater Chicago area, we observed high de facto reuse for some power plants and substantial costs for retrofitting to use reclaimed water. Conversely, the gains in reliability and performance through engineered reuse with cooling towers outweighed the energy investment in reclaimed water pumping. Our analysis yields quantitative results of reclaimed water feasibility and can inform sustainable management of water and energy.

  14. Data on test results of vessel cooling system of high temperature engineering test reactor

    Energy Technology Data Exchange (ETDEWEB)

    Saikusa, Akio [Secretariat of Nuclear Safety Commission, Tokyo (Japan); Nakagawa, Shigeaki; Fujimoto, Nozomu; Tachibana, Yukio; Iyoku, Tatsuo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    2003-02-01

    High Temperature Engineering Test Reactor (HTTR) is the first graphite-moderated helium gas cooled reactor in Japan. The rise-to-power test of the HTTR started on September 28, 1999 and thermal power of the HTTR reached its full power of 30 MW on December 7, 2001. Vessel Cooling System (VCS) of the HTTR is the first Reactor Cavity Cooling System (RCCS) applied for High Temperature Gas Cooled Reactors. The VCS cools the core indirectly through the reactor pressure vessel to keep core integrity during the loss of core flow accidents such as depressurization accident. Minimum heat removal of the VCS to satisfy its safety requirement is 0.3MW at 30 MW power operation. Through the performance test of the VCS in the rise-to-power test of the HTTR, it was confirmed that the VCS heat removal at 30 MW power operation was higher than 0.3 MW. This paper shows outline of the VCS and test results on the VCS performance. (author)

  15. Service the Two-Piece Flo-Jet Carburetor. Fuel System. Student Manual 3. Small Engine Repair Series. First Edition.

    Science.gov (United States)

    Hill, Pamela

    This student manual, part of a small-engine repair series on servicing fuel systems, is designed for use by special needs students in Texas. The manual explains in pictures and short sentences, written on a low reading level, the job of servicing two-piece flo-jet carburetors. Along with the steps of this repair job, specific safety and caution…

  16. Human Cardiac Tissue Engineering: From Pluripotent Stem Cells to Heart Repair

    Science.gov (United States)

    Jackman, Christopher P.; Shadrin, Ilya Y.; Carlson, Aaron L.; Bursac, Nenad

    2014-01-01

    Engineered cardiac tissues hold great promise for use in drug and toxicology screening, in vitro studies of human physiology and disease, and as transplantable tissue grafts for myocardial repair. In this review, we discuss recent progress in cell-based therapy and functional tissue engineering using pluripotent stem cell-derived cardiomyocytes and we describe methods for delivery of cells into the injured heart. While significant hurdles remain, notable advances have been made in the methods to derive large numbers of pure human cardiomyocytes, mature their phenotype, and produce and implant functional cardiac tissues, bringing the field a step closer to widespread in vitro and in vivo applications. PMID:25599018

  17. Sternal Repair with Bone Grafts Engineered from Amniotic Mesenchymal Stem Cells

    Science.gov (United States)

    Steigman, Shaun A.; Ahmed, Azra; Shanti, Rabie M.; Tuan, Rocky S.; Valim, Clarissa; Fauza, Dario O.

    2013-01-01

    Background We aimed at determining whether osseous grafts engineered from amniotic mesenchymal stem cells (aMSCs) could be employed in postnatal sternal repair. Methods Leporine aMSCs were isolated, identified, transfected with green fluorescent protein (GFP), expanded, and seeded onto biodegradable electrospun nanofibrous scaffolds (n=6). Constructs were dynamically maintained in an osteogenic medium and equally divided into two groups with respect to time in vitro, namely 14.6 or 33.9 weeks. They were then used to repair full thickness sternal defects spanning 2–3 intercostal spaces in allogeneic kits (n=6). Grafts were submitted to multiple analyses 2 months thereafter. Results Chest roentgenograms showed defect closure in all animals, confirmed at necropsy. Graft density as assessed by micro-CT scans increased significantly in vivo, yet there were no differences in mineralization by extracellular calcium measurements pre- and post-implantation. There was a borderline increase in alkaline phosphatase activity in vivo, suggesting ongoing graft remodeling. Histologically, implants contained GFP-positive cells and few mononuclear infiltrates. There were no differences between the two construct groups in any comparison. Conclusions Engineered osseous grafts derived from amniotic mesenchymal stem cells may become a viable alternative for sternal repair. The amniotic fluid can be a practical cell source for engineered chest wall reconstruction. PMID:19524727

  18. Effects of Engine Cooling Water Temperature on Performance and Emission Characteristics of a Ci Engine Operated with Biofuel Blend

    Directory of Open Access Journals (Sweden)

    Abul Hossain

    2017-03-01

    Full Text Available The temperature of the coolant is known to have significant influence on engine performance and emissions. Whereas existing literature describes the effects of coolant temperature in engines using fossil derived fuels, very few studies have investigated these effects when biofuel is used. In this study, Jatropha oil was blended separately with ethanol and butanol. It was found that the 80% jatropha oil + 20% butanol blend was the most suitable alternative, as its properties were closest to that of fossil diesel. The coolant temperature was varied between 50°C and 95°C. The combustion process enhanced for both diesel and biofuel blend, when the coolant temperature was increased. The carbon dioxide emissions for both diesel and biofuel blend were observed to increase with temperature. The carbon monoxide, oxygen and lambda values were observed to decrease with temperature. When the engine was operated using diesel, nitrogen oxides emissions correlated in an opposite manner to smoke opacity; however, nitrogen oxides emissions and smoke opacity correlated in an identical manner for biofuel blend. Brake specific fuel consumption was observed to decrease as the temperature was increased and was higher on average when the biofuel was used. The study concludes that both biofuel blend and fossil diesel produced identical correlations between coolant temperature and engine performance. The trends of nitrogen oxides and smoke emissions with cooling temperatures were not identical to fossil diesel when biofuel blend was used in the engine.

  19. Contingency power for small turboshaft engines using water injection into turbine cooling air

    Science.gov (United States)

    Biesiadny, Thomas J.; Berger, Brett; Klann, Gary A.; Clark, David A.

    1987-01-01

    Because of one engine inoperative requirements, together with hot-gas reingestion and hot day, high altitude takeoff situations, power augmentation for multiengine rotorcraft has always been of critical interest. However, power augmentation using overtemperature at the turbine inlet will shorten turbine life unless a method of limiting thermal and mechanical stresses is found. A possible solution involves allowing the turbine inlet temperature to rise to augment power while injecting water into the turbine cooling air to limit hot-section metal temperatures. An experimental water injection device was installed in an engine and successfully tested. Although concern for unprotected subcomponents in the engine hot section prevented demonstration of the technique's maximum potential, it was still possible to demonstrate increases in power while maintaining nearly constant turbine rotor blade temperature.

  20. Contingency power for a small turboshaft engine by using water injection into turbine cooling air

    Science.gov (United States)

    Biesiadny, Thomas J.; Klann, Gary A.

    1992-01-01

    Because of one-engine-inoperative (OEI) requirements, together with hot-gas reingestion and hot-day, high-altitude take-off situations, power augmentation for multiengine rotorcraft has always been of critical interest. However, power augmentation by using overtemperature at the turbine inlet will shorten turbine life unless a method of limiting thermal and mechanical stress is found. A possible solution involves allowing the turbine inlet temperature to rise to augment power while injecting water into the turbine cooling air to limit hot-section metal temperatures. An experimental water injection device was installed in an engine and successfully tested. Although concern for unprotected subcomponents in the engine hot section prevented demonstration of the technique's maximum potential, it was still possible to demonstrate increases in power while maintaining nearly constant turbine rotor blade temperature.

  1. Biomedical engineering strategies for peripheral nerve repair: surgical applications, state of the art, and future challenges.

    Science.gov (United States)

    Pfister, Bryan J; Gordon, Tessa; Loverde, Joseph R; Kochar, Arshneel S; Mackinnon, Susan E; Cullen, D Kacy

    2011-01-01

    Damage to the peripheral nervous system is surprisingly common and occurs primarily from trauma or a complication of surgery. Although recovery of nerve function occurs in many mild injuries, outcomes are often unsatisfactory following severe trauma. Nerve repair and regeneration presents unique clinical challenges and opportunities, and substantial contributions can be made through the informed application of biomedical engineering strategies. This article reviews the clinical presentations and classification of nerve injuries, in addition to the state of the art for surgical decision-making and repair strategies. This discussion presents specific challenges that must be addressed to realistically improve the treatment of nerve injuries and promote widespread recovery. In particular, nerve defects a few centimeters in length use a sensory nerve autograft as the standard technique; however, this approach is limited by the availability of donor nerve and comorbidity associated with additional surgery. Moreover, we currently have an inadequate ability to noninvasively assess the degree of nerve injury and to track axonal regeneration. As a result, wait-and-see surgical decisions can lead to undesirable and less successful "delayed" repair procedures. In this fight for time, degeneration of the distal nerve support structure and target progresses, ultimately blunting complete functional recovery. Thus, the most pressing challenges in peripheral nerve repair include the development of tissue-engineered nerve grafts that match or exceed the performance of autografts, the ability to noninvasively assess nerve damage and track axonal regeneration, and approaches to maintain the efficacy of the distal pathway and targets during the regenerative process. Biomedical engineering strategies can address these issues to substantially contribute at both the basic and applied levels, improving surgical management and functional recovery following severe peripheral nerve injury.

  2. Numerical and Experimental Study of a Cooling for Vanes in a Small Turbine Engine

    Directory of Open Access Journals (Sweden)

    Šimák Jan

    2016-01-01

    Full Text Available This paper is concerned with a cooling system for inlet guide vanes of a small turbine engine which are exposed to a high temperature gas leaving a combustion chamber. Because of small dimensions of the vanes, only a simple internal cavity and cooling holes can be realized. The idea was to utilize a film cooling technique. The proposed solution was simulated by means of a numerical method based on a coupling of CFD and heat transfer solvers. The numerical results of various scenarios (different coolant temperature, heat transfer to surroundings showed a desired decrease of the temperature, especially on the most critical part – the trailing edge. The numerical data are compared to results obtained by experimental measurements performed in a test facility in our institute. A quarter segment model of the inlet guide vanes wheel was equipped with thermocouples in order to verify an effect of cooling. Despite some uncertainty in the results, a verifiable decrease of the vane temperature was observed.

  3. Tissue-engineering strategies to repair joint tissue in osteoarthritis: nonviral gene-transfer approaches.

    Science.gov (United States)

    Madry, Henning; Cucchiarini, Magali

    2014-10-01

    Loss of articular cartilage is a common clinical consequence of osteoarthritis (OA). In the past decade, substantial progress in tissue engineering, nonviral gene transfer, and cell transplantation have provided the scientific foundation for generating cartilaginous constructs from genetically modified cells. Combining tissue engineering with overexpression of therapeutic genes enables immediate filling of a cartilage defect with an engineered construct that actively supports chondrogenesis. Several pioneering studies have proved that spatially defined nonviral overexpression of growth-factor genes in constructs of solid biomaterials or hydrogels is advantageous compared with gene transfer or scaffold alone, both in vitro and in vivo. Notably, these investigations were performed in models of focal cartilage defects, because advanced cartilage-repair strategies based on the principles of tissue engineering have not advanced sufficiently to enable resurfacing of extensively degraded cartilage as therapy for OA. These studies serve as prototypes for future technological developments, because they raise the possibility that cartilage constructs engineered from genetically modified chondrocytes providing autocrine and paracrine stimuli could similarly compensate for the loss of articular cartilage in OA. Because cartilage-tissue-engineering strategies are already used in the clinic, combining tissue engineering and nonviral gene transfer could prove a powerful approach to treat OA.

  4. Tissue engineering for articular cartilage repair – the state of the art

    Directory of Open Access Journals (Sweden)

    B Johnstone

    2013-05-01

    Full Text Available Articular cartilage exhibits little capacity for intrinsic repair, and thus even minor injuries or lesions may lead to progressive damage and osteoarthritic joint degeneration, resulting in significant pain and disability. While there have been numerous attempts to develop tissue-engineered grafts or patches to repair focal chondral and osteochondral defects, there remain significant challenges in the clinical application of cell-based therapies for cartilage repair. This paper reviews the current state of cartilage tissue engineering with respect to different cell sources and their potential genetic modification, biomaterial scaffolds and growth factors, as well as preclinical testing in various animal models. This is not intended as a systematic review, rather an opinion of where the field is moving in light of current literature. While significant advances have been made in recent years, the complexity of this problem suggests that a multidisciplinary approach – combining a clinical perspective with expertise in cell biology, biomechanics, biomaterials science and high-throughput analysis will likely be necessary to address the challenge of developing functional cartilage replacements. With this approach we are more likely to realise the clinical goal of treating both focal defects and even large-scale osteoarthritic degenerative changes in the joint.

  5. Tissue engineering applications: cartilage lesions repair by the use of autologous chondrocytes

    Directory of Open Access Journals (Sweden)

    L. De Franceschi

    2011-09-01

    Full Text Available Promising new therapies based on tissue engineering have been recently developed for cartilage repair. The association of biomaterials with autologous chondrocytes expanded in vitro can represent a useful tool to regenerate this tissue. The scaffolds utilised in such therapeutical applications should provide a pre-formed three-dimensional shape, prevent cells from floating out of the defect, have sufficient mechanical strength, facilitate uniform spread of cells and stimulate the phenotype of transplanted cells. Hyaff®-11 is a hyaluronic-acid based biodegradable polymer, that has been shown to provide successful cell carrier for tissue-engineered repair. From our findings we can state that human chondrocytes seeded on Hyaff®-11 are able to maintain in vitro the characteristic of differentiated cells, expressing and producing collagen type II and aggrecan which are the main markers of cartilage phenotype, down-regulating collagen type I. Moreover, it seems to be a useful scaffold for cartilage repair both in animal models and clinical trials in humans, favouring the formation of a hyaline-like tissue. In the light of these data, we can hypothesise, for the future, the use of autologous chondrocyte transplantation together with gene therapy as a treatment for rheumatic diseases such as osteoarthritis.

  6. Tissue engineering for articular cartilage repair--the state of the art.

    Science.gov (United States)

    Johnstone, Brian; Alini, Mauro; Cucchiarini, Magali; Dodge, George R; Eglin, David; Guilak, Farshid; Madry, Henning; Mata, Alvaro; Mauck, Robert L; Semino, Carlos E; Stoddart, Martin J

    2013-05-02

    Articular cartilage exhibits little capacity for intrinsic repair, and thus even minor injuries or lesions may lead to progressive damage and osteoarthritic joint degeneration, resulting in significant pain and disability. While there have been numerous attempts to develop tissue-engineered grafts or patches to repair focal chondral and osteochondral defects, there remain significant challenges in the clinical application of cell-based therapies for cartilage repair. This paper reviews the current state of cartilage tissue engineering with respect to different cell sources and their potential genetic modification, biomaterial scaffolds and growth factors, as well as preclinical testing in various animal models. This is not intended as a systematic review, rather an opinion of where the field is moving in light of current literature. While significant advances have been made in recent years, the complexity of this problem suggests that a multidisciplinary approach - combining a clinical perspective with expertise in cell biology, biomechanics, biomaterials science and high-throughput analysis will likely be necessary to address the challenge of developing functional cartilage replacements. With this approach we are more likely to realise the clinical goal of treating both focal defects and even large-scale osteoarthritic degenerative changes in the joint.

  7. EFFECTS OF COOLED EXTERNAL EXHAUST GAS RECIRCULATION ON DIESEL HOMOGENEOUS CHARGE COMPRESSION IGNITION ENGINE

    Institute of Scientific and Technical Information of China (English)

    SHI Lei; CUI Yi; DENG Kangyao

    2007-01-01

    The effects of cooled external exhaust gas recirculation (EGR) on the combustion and emission performance of diesel fuel homogeneous charge compression ignition (HCCI) are studied. Homogeneous mixture is formed by injecting fuel in-cylinder in the negative valve overlap (NVO) period. So, the HCCI combustion which has low NOx and smoke emission is achieved. Cooled external EGR can delay the start of combustion effectively, which is very useful for high cetane fuel (diesel) HCCI, because these fuels can easily self-ignition, which makes the start of combustion more early. External EGR can avoid the knock combustion of HCCI at high load which means that the EGR can expand the high load limit. HCCI maintains low smoke emission at various EGR rate and various load compared with conventional diesel engine because there is no fuel-rich area in cylinder.

  8. Design for micro-combined cooling, heating and power systems stirling engines and renewable power systems

    CERN Document Server

    2015-01-01

    ‘Design for Micro-Combined Cooling, Heating & Power Systems’ provides a manual for the technical and structural design of systems for supplying decentralised energy in residential buildings. It presents the micro-combined cooling, heating & power systems Stirling engines & renewable energy sources (mCCHP-SE-RES) systems in an accessible manner both for the public at large, and for professionals who conceive, design or commercialise such systems or their components.  The high performance levels of these systems are demonstrated within the final chapter by the results of an experiment in which a house is equipped with a mCCHP-SE-RES system. The reader is also familiarized with the conceptual, technical and legal aspects of modern domestic energy systems; the components that constitute these systems; and advanced algorithms for achieving the structural and technical design of such systems. In residential buildings, satisfying demands of durable development has gradually evolved from necessity to...

  9. The Effect of Using a Modified A/C System on the Cooling System Temperature of an Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Mukhtar M.A. Morad

    2017-05-01

    Full Text Available This study investigates the effect of using A/C refrigerant to reduce the temperature of the coolant in a vehicle cooling system. An increase in coolant temperature due to harsh working conditions increases fuel consumption and leads to a reduction in engine power. Modifying vehicle air-conditioning by passing the suction line of the A/C system through the heat exchanger located in the lower part of the radiator (down flow type can significantly improve the performance of the engine cooling system. The results show a reduction in the temperature of coolant within the cooling system, thus maintaining a controlled working temperature within the allowable limits

  10. Combined cooling and heating using a gas engine in a supermarket

    Energy Technology Data Exchange (ETDEWEB)

    Maidment, G.G. [South Bank Univ., London (United Kingdom). School of Engineering Systems and Design; Zhao, X.; Riffat, S.B. [Nottingham Univ. (United Kingdom). School of the Built Environment

    2001-07-01

    This paper reports the results of an investigation into the practical and economic viability of an integrated combined heating and cooling system in a supermarket. This system consists of a direct-drive screw compressor, which is powered by a throttle controlled gas engine. The waste heat from the engine is used to provide hot water for space heating and for general usage within the catering and toilet facilities in the supermarket. In this paper, the working principle of the novel system is first described. This details how the gas engine system may be integrated into the typical supermarket. The paper then describes a model, which is used to simulate the energy consumption of the supermarket. This is used to calculate the energy consumed by the conventional system and that used by a number of alternative combined heating and cooling system configurations, which are also described. The additional capital cost of each configuration is estimated and this is used to calculate the payback period. The results show that a payback period of 4.2 years may be achieved with a system that uses approximately 500,000 kWh per annum less primary energy than a conventional system. Finally, comparison between this system and a traditional Combined Heat and Power (CHP) installation is given. (author)

  11. Study on Self-Repairing Performance of Mineral Powder Lubrication Oil Additive to Engine

    Institute of Scientific and Technical Information of China (English)

    GUO Yan-bao; XU Bin-shi; XU Yi

    2004-01-01

    By means of the engine shelf test, the gas escape amount of bent axle box was measured before and after adding hydroxyl silicate mineral powder lubrication oil additives, and discovered that gas escape amount after self-repaired is obviously smaller than before, the average gas escape amount of each rotate speed descend 6.5 %. Watching friction surface with SEM, discovered that the part of net veins in the cylinder inner surface are smoothly patched. Analysis with energy spectroscopy, discovered that there are some changing of atom component. Proofed that through rub chemical reaction, hydroxyl silicate mineral powder lubrication oil additives can generate new substance layer on friction surface, and can increase cylinder inner surface bulk, thereby get the repaired effects.

  12. Potential Applications of the Ceramic Thrust Chamber Technology for Future Transpiration Cooled Rocket Engines

    Science.gov (United States)

    Herbertz, Armin; Ortelt, Markus; Müller, Ilja; Hald, Hermann

    The long-term development of ceramic rocket engine thrust chambers at the German Aerospace Center(DLR) currently leads to designs of self-sustaining, transpiration-cooled, fiber-reinforced ceramic rocket engine chamber structures.This paper discusses characteristic issues and potential benefits introduced by this technology. Achievable benefits are the reduction of weight and manufacturing cost, as well as an increased reliability and higher lifetime due to thermal cycle stability.Experiments with porous Ceramic Matrix Composite(CMC) materials for rocket engine chamber walls have been conducted at the DLR since the end of the 1990s.This paper discusses the current status of DLR's ceramic thrust chamber technology and potential applications for high thrust engines.The manufacturing process and the design concept are explained.The impact of variations of engine parameters(chamber pressure and diam-eter)on the required coolant mass flow are discussed.Due to favorable scaling effects a high thrust application utilizes all benefits of the discussed technology, while avoiding the most significant performance drawbacks.

  13. AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XXV, I--CATERPILLAR DIESEL ENGINE COOLING SYSTEM D-8 AND 824 MODELS, II--TIRES AND TIRE HARDWARE.

    Science.gov (United States)

    Minnesota State Dept. of Education, St. Paul. Div. of Vocational and Technical Education.

    THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATION AND MAINTENANCE OF THE DIESEL ENGINE COOLING SYSTEM AND TO PROVIDE A DESCRIPTION OF HEAVY TIRES AND WHEELS USED ON DIESEL POWERED VEHICLES. TOPICS ARE (1) THEORY OF THE COOLING SYSTEM, (2) COOLING SYSTEM COMPONENTS, (3) MAINTENANCE TIPS (COOLING SYSTEM), (4)…

  14. Structural engineering developments in power plant cooling tower construction. 100 years of natural draught cooling towers - from tower cooler to cooling tower. Bautechnische Entwicklungen im Kraftwerkskuehlturmbau. 100 Jahre Naturzugkuehltuerme - vom Kaminkuehler zum Kuehlkamin

    Energy Technology Data Exchange (ETDEWEB)

    Damjakob, H.; Depe, T.; Vrangos, V. (Balcke-Duerr AG, Ratingen (Germany))

    1992-06-01

    Almost exactly 100 years ago, tower-type structures were first used for the production of artificial ventilation for cooling purposes. The shell of these so-called tower coolers, today known as 'natural draught cooling towers', was, from the outset, the subject of multiple structural engineering develepments in respect of design, material, construction and statistical calculation. These developments have been stimulated especially by the spasmodic increase in dimensions in the application of power plant cooling towers and, more recently, in connection with ecological requirements. (orig.).

  15. Engineering a multimodal nerve conduit for repair of injured peripheral nerve

    Science.gov (United States)

    Quigley, A. F.; Bulluss, K. J.; Kyratzis, I. L. B.; Gilmore, K.; Mysore, T.; Schirmer, K. S. U.; Kennedy, E. L.; O'Shea, M.; Truong, Y. B.; Edwards, S. L.; Peeters, G.; Herwig, P.; Razal, J. M.; Campbell, T. E.; Lowes, K. N.; Higgins, M. J.; Moulton, S. E.; Murphy, M. A.; Cook, M. J.; Clark, G. M.; Wallace, G. G.; Kapsa, R. M. I.

    2013-02-01

    hydrogel. This indicates return of some feeling to the limb via the fully-configured conduit. Immunohistochemical analysis of the implanted conduits removed from the rats after the four-week implantation period confirmed the presence of myelinated axons within the conduit and distal to the site of implantation, further supporting that the conduit promoted nerve repair over this period of time. This study describes the design considerations and fabrication of a novel multicomponent, multimodal bio-engineered synthetic conduit for peripheral nerve repair.

  16. Heat transfer in rocket engine combustion chambers and regeneratively cooled nozzles

    Science.gov (United States)

    1993-01-01

    A conjugate heat transfer computational fluid dynamics (CFD) model to describe regenerative cooling in the main combustion chamber and nozzle and in the injector faceplate region for a launch vehicle class liquid rocket engine was developed. An injector model for sprays which treats the fluid as a variable density, single-phase media was formulated, incorporated into a version of the FDNS code, and used to simulate the injector flow typical of that in the Space Shuttle Main Engine (SSME). Various chamber related heat transfer analyses were made to verify the predictive capability of the conjugate heat transfer analysis provided by the FDNS code. The density based version of the FDNS code with the real fluid property models developed was successful in predicting the streamtube combustion of individual injector elements.

  17. Nerve autografts and tissue-engineered materials for the repair of peripheral nerve injuries: a 5-year bibliometric analysis

    Directory of Open Access Journals (Sweden)

    Yuan Gao

    2015-01-01

    Full Text Available With advances in biomedical methods, tissue-engineered materials have developed rapidly as an alternative to nerve autografts for the repair of peripheral nerve injuries. However, the materials selected for use in the repair of peripheral nerve injuries, in particular multiple injuries and large-gap defects, must be chosen carefully. Various methods and materials for protecting the healthy tissue and repairing peripheral nerve injuries have been described, and each method or material has advantages and disadvantages. Recently, a large amount of research has been focused on tissue-engineered materials for the repair of peripheral nerve injuries. Using the keywords "pe-ripheral nerve injury", "autotransplant", "nerve graft", and "biomaterial", we retrieved publications using tissue-engineered materials for the repair of peripheral nerve injuries appearing in the Web of Science from 2010 to 2014. The country with the most total publications was the USA. The institutions that were the most productive in this field include Hannover Medical School (Germany, Washington University (USA, and Nantong University (China. The total number of publications using tissue-engineered materials for the repair of peripheral nerve injuries grad-ually increased over time, as did the number of Chinese publications, suggesting that China has made many scientific contributions to this field of research.

  18. Cell-based tissue engineering strategies used in the clinical repair of articular cartilage

    Science.gov (United States)

    Huang, Brian J.; Hu, Jerry C.; Athanasiou, Kyriacos A.

    2016-01-01

    One of the most important issues facing cartilage tissue engineering is the inability to move technologies into the clinic. Despite the multitude of review articles on the paradigm of biomaterials, signals, and cells, it is reported that 90% of new drugs that advance past animal studies fail clinical trials (1). The intent of this review is to provide readers with an understanding of the scientific details of tissue engineered cartilage products that have demonstrated a certain level of efficacy in humans, so that newer technologies may be developed upon this foundation. Compared to existing treatments, such as microfracture or autologous chondrocyte implantation, a tissue engineered product can potentially provide more consistent clinical results in forming hyaline repair tissue and in filling the entirety of the defect. The various tissue engineering strategies (e.g., cell expansion, scaffold material, media formulations, biomimetic stimuli, etc.) used in forming these products, as collected from published literature, company websites, and relevant patents, are critically discussed. The authors note that many details about these products remain proprietary, not all information is made public, and that advancements to the products are continuously made. Nevertheless, by fully understanding the design and production processes of these emerging technologies, one can gain tremendous insight into how to best use them and also how to design the next generation of tissue engineered cartilage products. PMID:27177218

  19. Repair of acutely injured spinal cord through constructing tissue-engineered neural complex in adult rats

    Institute of Scientific and Technical Information of China (English)

    PU Yu; GUO Qing-shan; WANG Ai-min; WU Si-yu; XING Shu-xing; ZHANG Zhong-rong

    2007-01-01

    Objective: To construct tissue-engineered neural complex in vitro and study its effect in repairing acutely injured spinal cord in adult rats. Methods: Neural stem cells were harvested from the spinal cord of embryo rats and propagated in vitro. Then the neural stem cells were seeded into polyglycolic acid scaffolds and co-cultured with extract of embryonic spinal cord in vitro. Immunofluorescence histochemistry and scanning electron microscope were used to observe the microstructure of this complex. Animal model of spine semi-transection was made and tissue-engineered neural complex was implanted by surgical intervention. Six weeks after transplantation, functional evaluation and histochemistry were applied to evaluate the functional recovery and anatomic reconstruction. Results: The tissue-engineered neural complex had a distinct structure, which contained neonatal neurons, oligodendrocytes and astrocytes. After tissue-engineered neural complex was implanted into the injured spinal cord, the cell components such as neurons, astrocytes and oligodendrocytes, could survive and keep on developing. The adult rats suffering from spinal cord injury got an obvious neurological recovery in motor skills. Conclusions: The tissue-engineered neural complex appears to have therapeutic effects on the functional recovery and anatomic reconstruction of the adult rats with spinal cord injury.

  20. A direct numerical simulation of cool-flame affected autoignition in diesel engine-relevant conditions

    Energy Technology Data Exchange (ETDEWEB)

    Krisman, Alexander; Hawkes, Evatt Robert.; Talei, Mohsen; Bhagatwala, Ankit; Chen, Jacqueline H.

    2016-11-11

    In diesel engines, combustion is initiated by a two-staged autoignition that includes both low- and high-temperature chemistry. The location and timing of both stages of autoignition are important parameters that influence the development and stabilisation of the flame. In this study, a two-dimensional direct numerical simulation (DNS) is conducted to provide a fully resolved description of ignition at diesel engine-relevant conditions. The DNS is performed at a pressure of 40 atmospheres and at an ambient temperature of 900 K using dimethyl ether (DME) as the fuel, with a 30 species reduced chemical mechanism. At these conditions, similar to diesel fuel, DME exhibits two-stage ignition. The focus of this study is on the behaviour of the low-temperature chemistry (LTC) and the way in which it influences the high-temperature ignition. The results show that the LTC develops as a “spotty” first-stage autoignition in lean regions which transitions to a diffusively supported cool-flame and then propagates up the local mixture fraction gradient towards richer regions. The cool-flame speed is much faster than can be attributed to spatial gradients in first-stage ignition delay time in homogeneous reactors. The cool-flame causes a shortening of the second-stage ignition delay times compared to a homogeneous reactor and the shortening becomes more pronounced at richer mixtures. Multiple high-temperature ignition kernels are observed over a range of rich mixtures that are much richer than the homogeneous most reactive mixture and most kernels form much earlier than suggested by the homogeneous ignition delay time of the corresponding local mixture. Altogether, the results suggest that LTC can strongly influence both the timing and location in composition space of the high-temperature ignition.

  1. Repair of Sheep Metatarsus Defects by Using Tissue-engineering Technique

    Institute of Scientific and Technical Information of China (English)

    LI Zhanghua; YANG Yi; WANG Changyong; XIA Renyun; ZHANG Yufu; ZHAO Qiang; LIAO Wen; WANG Yonghong; LU Jianxi

    2005-01-01

    Tissue-engineering bone with porous β-tricalcium phosphate (β-TCP) ceramic and autologous bone marrow mesenchymal stem cells (MSC) was constructed and the effect of this composite on healing of segmental bone defects was investigated. 10-15 ml bone marrow aspirates were harvested from the iliac crestof sheep, and enriched for MSC by density gradient centrifugation over a Percoll cushion (1. 073 g/ml). After cultured and proliferated, tissue-engineering bones were constructed with these cells seeded onto porous β-TCP, and then the constructs were implanted in 8 sheep left metatarsus defect (25 mm in length) as experimental group. Porous β-TCP only were implanted to bridge same size and position defects in 8 sheep as control group, and 25 mm segmental bone defects of left metatarsus were left empty in 4 sheep as blank group. Sheep were sacrificed on the 6th, 12th, and 24th week postoperatively and the implants samples were examined by radiograph, histology, and biomechanical test. The 4 sheep in blank group were sacrificed on the 24th week postoperatively. The results showed that new bone tissues were observed either radiographic or histologically at the defects of experimental group as early as 6th week postoperatively, but not in control group, and osteoid tissue, woven bone and lamellar bone occurred earlier than in control group in which the bone defects were repaired in "creep substitution" way, because of the new bone formed in direct manner without progression through a cartilaginous intermediate. At the 24th week, radiographs and biomechanical test revealed an almost complete repair of the defect of experimental group, only partly in control group. The bone defects in blank group were non-healing at the 24th week. It was concluded that engineering bones constructed with porous β-TCP and autologous MSC were capable of repairing segmental bone defects in sheep metatarsus beyond "creep substitution" way and making it healed earlier. Porous β-TCP being

  2. Detection of abnormalities in the superficial zone of cartilage repaired using a tissue engineered construct derived from synovial stem cells

    OpenAIRE

    Ando, W.; FUJIE, H; Moriguchi, Y.; Nansai, R.; Shimomura, K.; DA Hart; Yoshikawa, H; Nakamura, N.

    2012-01-01

    The present study investigated the surface structure and mechanical properties of repair cartilage generated from a tissue engineered construct (TEC) derived from synovial mesenchymal stem cells at six months post-implantation compared to those of uninjured cartilage. TEC-mediated repair tissue was cartilaginous with Safranin O staining, and had comparable macro-scale compressive properties with uninjured cartilage. However, morphological assessments revealed that the superficial zone of TEC-...

  3. Repair of flexor tendon defects of rabbit with tissue engineering method

    Institute of Scientific and Technical Information of China (English)

    何清义; 李起鸿; 陈秉礼; 王智彪

    2002-01-01

    To repair rabbit tendon defects with tissue engineering method. Methods: The third passage of fetal skin fibroblast cells was labeled with 5-bromo-2' deoxyuridine (Brdu) and then seeded on human amnion extracellular matrix (HA-ECM). Using 1 cm-long-Achilles tendon .defects as repairing models in the experimental group, tendon defects were core bridged with polydioxanone (PDS) and then capsulated with the complex of fibroblasts-HA-ECM. In the control group I, defective tendons were sutured with PDS following the former procedure and capsulated with HA-ECM (without fibroblasts). In the control group Ⅱ,only PDS was applied to connect the defective tendons.Gross examination, light microscopy, scanning electronmicroscopy and biomechanical measurement of the repaired tendons were respectively performed at postoperative 1, 2, 3 month as well as immunohistochemical examination. Results: The optimal cell concentration for seeding fibroblasts was 3.5 × 106 cells/ml. Cells grew well and radiated or paralleled on HA-ECM. Immunohistochemistry showed that the labeled seed fibroblasts played an important role in tendonization. The results of light microscopy,electron microscopy, and biomechanical assessment suggested that the rate and quality of tendonization in the experimental group was superior to those of the control group Ⅰ and Ⅱ. The tensile strength in the experimental group was the greatest, the next was in the control group Ⅰ,and the worst in the control group Ⅱ ( P < 0.05). Conclusions: HA-ECM is the excellent carrier for fibroblasts. Fibroblasts-HA-ECM complex has the capability to repair tendon defect and to tendonize with rapid rate and good performance three months after operation. Its tensile strength is 81.8% of that of normal tendon.

  4. Conjugate Heat transfer Analysis of helical fins with airfoil crosssection and its comparison with existing circular fin design for air cooled engines employing constant rectangular cross-section

    Directory of Open Access Journals (Sweden)

    Ashwin Shridhar

    2015-06-01

    Full Text Available Air Cooled Engines have been used in a variety of applications, ranging from airplanes to motorbikes and even stationary or portable engines. Since modern automobiles and airplanes use engines delivering more power, they have to be cooled more efficiently due to which a more complex water cooling system is used for cooling engines with large displacements. Hence air cooling is becoming a thing of the past, especially in the aviation sector due to the advent of more efficient gas turbine engines. However air cooled internal combustion engines are still being used in a wide variety of two-wheelers ranging from small single cylinder engines to heavy duty liter class V-twins and Inline fours, due to the non-practicalities associated with the installment of a bulky water cooling system in two-wheelers. So one can ascertain that there is a scope for improving the efficiency of air cooled engines even further. The objective of this paper is to analyze currently existing fin design employed in most of the air cooled engines and improve it by changing the cross-section to a streamlined one and also making the fins in a helical orientation as opposed to the regular circular fins employed. Our analysis comprises of a computational fluid dynamics study of both the fin models with identical dimensions and simulated in the same environment using ANSYS FLUENT 15 software and we attempt to compare their performance using the temperature and heat transfer coefficient distribution plots obtained.

  5. Numerical investigation on super-cooled large droplet icing of fan rotor blade in jet engine

    Science.gov (United States)

    Isobe, Keisuke; Suzuki, Masaya; Yamamoto, Makoto

    2014-10-01

    Icing (or ice accretion) is a phenomenon in which super-cooled water droplets impinge and accrete on a body. It is well known that ice accretion on blades and vanes leads to performance degradation and has caused severe accidents. Although various anti-icing and deicing systems have been developed, such accidents still occur. Therefore, it is important to clarify the phenomenon of ice accretion on an aircraft and in a jet engine. However, flight tests for ice accretion are very expensive, and in the wind tunnel it is difficult to reproduce all climate conditions where ice accretion can occur. Therefore, it is expected that computational fluid dynamics (CFD), which can estimate ice accretion in various climate conditions, will be a useful way to predict and understand the ice accretion phenomenon. On the other hand, although the icing caused by super-cooled large droplets (SLD) is very dangerous, the numerical method has not been established yet. This is why SLD icing is characterized by splash and bounce phenomena of droplets and they are very complex in nature. In the present study, we develop an ice accretion code considering the splash and bounce phenomena to predict SLD icing, and the code is applied to a fan rotor blade. The numerical results with and without the SLD icing model are compared. Through this study, the influence of the SLD icing model is numerically clarified.

  6. Flow visualization study in high aspect ratio cooling channels for rocket engines

    Science.gov (United States)

    Meyer, Michael L.; Giuliani, James E.

    1993-11-01

    The structural integrity of high pressure liquid propellant rocket engine thrust chambers is typically maintained through regenerative cooling. The coolant flows through passages formed either by constructing the chamber liner from tubes or by milling channels in a solid liner. Recently, Carlile and Quentmeyer showed life extending advantages (by lowering hot gas wall temperatures) of milling channels with larger height to width aspect ratios (AR is greater than 4) than the traditional, approximately square cross section, passages. Further, the total coolant pressure drop in the thrust chamber could also be reduced, resulting in lower turbomachinery power requirements. High aspect ratio cooling channels could offer many benefits to designers developing new high performance engines, such as the European Vulcain engine (which uses an aspect ratio up to 9). With platelet manufacturing technology, channel aspect ratios up to 15 could be formed offering potentially greater benefits. Some issues still exist with the high aspect ratio coolant channels. In a coolant passage of circular or square cross section, strong secondary vortices develop as the fluid passes through the curved throat region. These vortices mix the fluid and bring lower temperature coolant to the hot wall. Typically, the circulation enhances the heat transfer at the hot gas wall by about 40 percent over a straight channel. The effect that increasing channel aspect ratio has on the curvature heat transfer enhancement has not been sufficiently studied. If the increase in aspect ratio degrades the secondary flow, the fluid mixing will be reduced. Analysis has shown that reduced coolant mixing will result in significantly higher wall temperatures, due to thermal stratification in the coolant, thus decreasing the benefits of the high aspect ratio geometry. A better understanding of the fundamental flow phenomena in high aspect ratio channels with curvature is needed to fully evaluate the benefits of this

  7. Single-Cylinder Engine Tests of Porous Chrome-Plated Cylinder Barrels with Special Bore Coatings for Radial Air-Cooled Engines

    Science.gov (United States)

    1946-01-01

    sulphamate solution at room temperature having a hydrogen-ion concentration of 1.5. The cylinder was plated for 2 minutes with a current density of 40...for any metal combination (reference 3), engine friction may be reduced somewhat by the use of a silver overplate as a bearing material on the...Cooled Engines. NACA ARR No. E5L18, 1945. 3. Hoyt, Samuel L.: Metals and Alloys Data Book. Reinhold Pub. Corp., 1943, p. 281. 4. Downing, B. F

  8. A qualitative engineering analysis of occlusion effects on mandibular fracture repair mechanics.

    Science.gov (United States)

    Katona, Thomas R

    2011-01-01

    Objectives. The purpose of this analytical study was to examine and critique the engineering foundations of commonly accepted biomechanical principles of mandible fracture repair. Materials and Methods. Basic principles of static equilibrium were applied to intact and plated mandibles, but instead of the traditional lever forces, the mandibles were subjected to more realistic occlusal forces. Results. These loading conditions produced stress distributions within the intact mandible that were very different and more complex than the customary lever-based gradient. The analyses also demonstrated the entirely different mechanical environments within intact and plated mandibles. Conclusions. Because the loading and geometry of the lever-idealized mandible is incomplete, the associated widely accepted bone stress distribution (tension on top and compression on the bottom) should not be assumed. Furthermore, the stress gradients within the bone of an intact mandible should not be extrapolated to the mechanical environment within the plated regions of a fractured mandible.

  9. Durability of zirconia thermal-barrier ceramic coatings on air-cooled turbine blades in cyclic jet engine operation

    Science.gov (United States)

    Liebert, C. H.; Jacobs, R. E.; Stecura, S.; Morse, C. R.

    1976-01-01

    Thermal barrier ceramic coatings of stabilized zirconia over a bond coat of Ni Cr Al Y were tested for durability on air cooled turbine rotor blades in a research turbojet engine. Zirconia stabilized with either yttria, magnesia, or calcia was investigated. On the basis of durability and processing cost, the yttria stabilized zirconia was considered the best of the three coatings investigated.

  10. Flow Integrating Section for a Gas Turbine Engine in Which Turbine Blades are Cooled by Full Compressor Flow

    Energy Technology Data Exchange (ETDEWEB)

    Steward, W. Gene

    1999-11-14

    Routing of full compressor flow through hollow turbine blades achieves unusually effective blade cooling and allows a significant increase in turbine inlet gas temperature and, hence, engine efficiency. The invention, ''flow integrating section'' alleviates the turbine dissipation of kinetic energy of air jets leaving the hollow blades as they enter the compressor diffuser.

  11. Reliability and safety of the K Reactor cooling system: Part 2, Engineering analysis of hydraulic and mechanical aspects

    Energy Technology Data Exchange (ETDEWEB)

    Shoemaker, R.H.

    1960-04-04

    Subsequent to the recent formulation and adoption of safety criteria for reactor cooling systems, there appeared the need for an independent evaluation of the safety and reliability of the K-Reactor cooling system in terms of these criteria. The primary, secondary and last-ditch cooling systems of this reactor involve a strong inter-dependence between electrical and hydraulic components of the water plant. Because of the complexity of inter-relationships between these components, the analysis was divided into two parallel studies which were accomplished during the simmer of 1959. F. D. Robbins has presented his analysis of the electrical power and control system in HW-61887. This report deals with an engineering analysis of the hydraulic and mechanical aspects of the reliability and safety of the K-Reactor Cooling System. The system, as described in this report, is that which existed during the simmer of 1959, prior to modification under Project CG-775 (now Project CG-883).

  12. Repair of osteochondral defects with in vitro engineered cartilage based on autologous bone marrow stromal cells in a swine model

    Science.gov (United States)

    He, Aijuan; Liu, Lina; Luo, Xusong; Liu, Yu; Liu, Yi; Liu, Fangjun; Wang, Xiaoyun; Zhang, Zhiyong; Zhang, Wenjie; Liu, Wei; Cao, Yilin; Zhou, Guangdong

    2017-01-01

    Functional reconstruction of large osteochondral defects is always a major challenge in articular surgery. Some studies have reported the feasibility of repairing articular osteochondral defects using bone marrow stromal cells (BMSCs) and biodegradable scaffolds. However, no significant breakthroughs have been achieved in clinical translation due to the instability of in vivo cartilage regeneration based on direct cell-scaffold construct implantation. To overcome the disadvantages of direct cell-scaffold construct implantation, the current study proposed an in vitro cartilage regeneration strategy, providing relatively mature cartilage-like tissue with superior mechanical properties. Our strategy involved in vitro cartilage engineering, repair of osteochondral defects, and evaluation of in vivo repair efficacy. The results demonstrated that BMSC engineered cartilage in vitro (BEC-vitro) presented a time-depended maturation process. The implantation of BEC-vitro alone could successfully realize tissue-specific repair of osteochondral defects with both cartilage and subchondral bone. Furthermore, the maturity level of BEC-vitro had significant influence on the repaired results. These results indicated that in vitro cartilage regeneration using BMSCs is a promising strategy for functional reconstruction of osteochondral defect, thus promoting the clinical translation of cartilage regeneration techniques incorporating BMSCs. PMID:28084417

  13. Maintenance And Repair of Automotive Engine%汽车发动机的维护及保养

    Institute of Scientific and Technical Information of China (English)

    白有俊

    2014-01-01

    Correct and reasonable maintenance and repair of automotive engine is an important link to improve technical performance of the automobile, extend its life, reduce economic losses and ensure traffic safety. The article discusses in details how to have the reasonable and effective maintenance and repair for the automotive engine from the related engine knowledge.%正确合理地对汽车发动机进行维护和保养是提高汽车技术性能,延长其使用寿命,减少经济损失,保证行车安全的重要环节。文章从论述发动机相关知识等入手,对如何进行合理有效的汽车发动机维护和保养两个方面进行详细阐述。

  14. COGENERATION OPPORTUNITIES TO IMPROVE THE EFFICIENCY OF MICRO HEAT POWER PLANTS BASED ON AIR COOLED INTERNAL COMBUSTION ENGINES

    Directory of Open Access Journals (Sweden)

    P. A. Shchinnikov

    2017-01-01

    Full Text Available The possibilities of operation of electric generators based on internal combustion engines with air cooling under conditions of cogeneration, when, along with the electricity, heat release in different embodiments is provided. Such facilities are usually realized on the basis of gasoline internal combustion engines (i.e. gasoline is used as a fuel. They can be used in the household, by professional builders, geologists, the military and rescuers in the area of emergencies and in areas with a lack of infrastructure. The basis of the facility is the gasoline generator Hitachi-2400 with an air-cooled power of 2.4 kW. The basic methodology for the study of microthermal power plants based on an air-cooled internal combustion engine which is based on balance equations is presented. The facility operation ensures the measurement of all temperatures and expenses of operating environments for determining heat flow in accordance with the proposed methodology. The specifications of heat exchangers for utilizing the heat of exhaust flue gases are presented. The energy diagram illustrating the useful effect of the application of various heat exchangers are plotted. Cogeneration possibilities of the facility are provided, firstly, by the release of heat with the air that cools a cylinder of the internal combustion engine, and, secondly, by the release of heat of hot water heated by utilizing the heat of the leaving flue gases, and, thirdly, in the calculated version, by the release of heat with air that is sequentially heated due to the cooling of the cylinder head and then by utilizing the heat of exhaust gases. It is demonstrated that the fuel heat utilization factor can be increased from 0.22 to 0.50–0.60, depending on the adopted technical solutions.

  15. Safe corrosion inhibitor for treating cooling water on heat power engineering plants

    Science.gov (United States)

    Nikolaeva, L. A.; Khasanova, D. I.; Mukhutdinova, E. R.; Safin, D. Kh.; Sharifullin, I. G.

    2017-08-01

    Heat power engineering (HPE) consumes significant volumes of water. There are, therefore, problems associated with corrosion, biological fouling, salt deposits, and sludge formation on functional surfaces of heat power equipment. One of the effective ways to solve these problems is the use of inhibitory protection. The development of new Russian import-substituting environmentally friendly inhibitors is very relevant. This work describes experimental results on the OPC-800 inhibitor (TU 2415-092-00206 457-2013), which was produced at Karpov Chemical Plant and designed to remove mineral deposits, scale, and biological fouling from the surfaces of water-rotation node systems on HPE objects. This reagent is successfully used as an effective corrosion inhibitor in the water recycling systems of Tatarstan petrochemical enterprises. To save fresh make-up water, the circulating system is operated in a no-blow mode, which is characterized by high evaporation and salt content coefficients. It was experimentally found that corrosion rate upon treatment of recycled water with the OPC-800 inhibitor is 0.08-0.10 mm/year. HPE mainly uses inhibitors based on oxyethylidene diphosphonic (OEDPA) and nitrilotrimethylphosphonic (NTMPA) acids. The comparative characteristic of inhibition efficiency for OPC-800 and OEDF-Zn-U2 is given. The results obtained indicate that OPC-800 can be used as an inhibitor for treatment of cooling water in HPE plants. In this case, it is necessary to take into account the features of water rotation of a thermal power plant.

  16. Repairing peripheral nerve defects with tissue engineered artificial nerves in rats

    Institute of Scientific and Technical Information of China (English)

    WEI Ai-lin; LIU Shi-qing; TAO Hai-ying; PENG Hao

    2008-01-01

    Objective: To observe the effect of tissue engineered nerves in repairing peripheral nerve defects ( about 1. 5 cm in length) in rats to provide data for clinical application.Methods: Glycerinated sciatic nerves (2 cm in length) from 10 Sprague Dawley ( SD) rats ( aged 4 months) were used to prepare homologous dermal acellular matrix. Other 10 neonate SD rats (aged 5-7 days) were killed by neck dislocation. After removing the epineurium, the separated sciatic nerve tracts were cut into small pieces, then digested by 2.5 g/L trypsin and 625 U/ml collagenase and cultured in Dulbecco's modified Eagle's medium (DMEM) for 3 weeks. After proliferation, the Schwann cells ( SCs) were identified and prepared for use. And other 40 female adult SD rats (weighing 200 g and aged 3 months) with sciatic nerve defects of 1.5 cm in length were randomly divided into four groups: the defects of 10 rats bridged with proliferated SCs and homologous dermal acellular matrix (the tissue engineered nerve group, Group A), 10 rats with no SCs but homologous dermal acellular matrix with internal scaffolds ( Group B ), 10 with autologous nerves ( Group C) , and the other 10 with nothing (the blank control group, Group D). The general status of the rats was observed, the wet weight of triceps muscle of calf was monitored, and the histological observation of the regenerated nerves were made at 12 weeks after operation.Results: The wounds of all 40 rats healed after operation and no death was found. No foot ulceration was found in Groups A, B and C, but 7 rats suffered from foot ulceration in Group D. The triceps muscles of calf were depauperated in the experimental sides in all the groups compared with the uninjured sides,which was much more obvious in Group D. The wet weight of triceps muscle of calf and nerve electrophysiologic monitoring showed no statistical difference between Group A and Group C,but statistical difference was found between Groups A and B and Groups B and D. And significant

  17. 工程机械冷却系统研究%On the Cooling System of Engineering Machinery

    Institute of Scientific and Technical Information of China (English)

    张连永

    2015-01-01

    发动机作为汽车的主要部件,其性能直接决定了汽车质量的好坏.长期研究发现,发动机只利用了热能的1/3,其余2/3热量都随着冷却空气散入大气,剩余的则被发动机零部件吸收.设备的运行工况及服务年限直接取决于冷却系统设计的合理性.因此,为保证发动机正常工作,必须对这些在高温条件下工作的机件加以冷却.%The engine as the main component of the car, its performance directly determines the quality of the car. Long-term study found that the engine only used one-thirds of heat, and the remaining two-thirds of the heat was scattered into the atmosphere along with the cooling air, the remaining were absorbed by engine parts. Operating conditions and the service life of the device depends directly on the reasonableness of the cooling system design. Therefore, to ensure the normal operation of the engine, these parts working under high temperature conditions must be cooled.

  18. METHODOLOGY FOR ESTIMATION OF HEAT-STRESSED STATE FOR CYLINDER HEAD OF DIESEL ENGINE WITH AIR COOLING

    Directory of Open Access Journals (Sweden)

    A. N. Avramenko

    2016-01-01

    Full Text Available Performance tuning improvement of modern diesel engines exerts an influence on technical and economic, ecological and resource indices of an internal combustion engine (ICE. In its turn, that requires a complex estimation and improvement of engine indices. As is known, working process and thermal intensity of combustion chamber parts are interconnected between themselves. Changes in design, operating and adjustment parameters of systems and structural elements of internal combustion engines that enable air-fuel mixing and combustions processes stressed state of combustion chamber parts. Joint estimation of operating cycle parameters and strength indices of ICE parts makes it possible to solve a number of problems originating in the process of designing new engine models and further development of the existing ones. The paper provides results of comparative estimation on heat-stressed state of a cylinder head for a high-speed diesel engine Д21A (2Ч10,5/12 while operating a rated power mode. In order to simulate and specify a heat-stressed state for description of boundary heat conductivity conditions the following adjoint “gas – wall” problems have been solved: the first one – for combustion chamber of a diesel engine (an internal problem – simulation of a working cycle for a diesel engine; the second one – for cooling edges while blowing over them by air flow (an external problem. Calculations have been made in three-dimensional non-stationary presentation within the Cartesian coordinates. In order to simulate a working cycle of the diesel engine a computational grid describing combustion chamber configuration, inlet and outlet channels has been used in the paper. Solution of the external problem for cooling edge surface in case of blowing over them by air flow has permitted to specify temperatures and heat-transfer coefficient and later to improve an accuracy while estimating level of temperatures and stresses of the cylinder head.

  19. Service Cart For Engines

    Science.gov (United States)

    Ng, Gim Shek

    1995-01-01

    Cart supports rear-mounted air-cooled engine from Volkswagen or Porsche automobile. One person removes, repairs, tests, and reinstalls engine of car, van, or home-built airplane. Consists of framework of wood, steel, and aluminum components supported by four wheels. Engine lifted from vehicle by hydraulic jack and gently lowered onto waiting cart. Jack removed from under engine. Rear of vehicle raised just enough that engine can be rolled out from under it. Cart easily supports 200-lb engine. Also used to hold transmission. With removable sheet-metal top, cart used as portable seat.

  20. Service Cart For Engines

    Science.gov (United States)

    Ng, Gim Shek

    1995-01-01

    Cart supports rear-mounted air-cooled engine from Volkswagen or Porsche automobile. One person removes, repairs, tests, and reinstalls engine of car, van, or home-built airplane. Consists of framework of wood, steel, and aluminum components supported by four wheels. Engine lifted from vehicle by hydraulic jack and gently lowered onto waiting cart. Jack removed from under engine. Rear of vehicle raised just enough that engine can be rolled out from under it. Cart easily supports 200-lb engine. Also used to hold transmission. With removable sheet-metal top, cart used as portable seat.

  1. Transplantation of genetically engineered cardiac fibroblasts producing recombinant human erythropoietin to repair the infarcted myocardium

    Directory of Open Access Journals (Sweden)

    Ruvinov Emil

    2008-11-01

    Full Text Available Abstract Background Erythropoietin possesses cellular protection properties. The aim of the present study was to test the hypothesis that in situ expression of recombinant human erythropoietin (rhEPO would improve tissue repair in rat after myocardial infarction (MI. Methods and results RhEPO-producing cardiac fibroblasts were generated ex vivo by transduction with retroviral vector. The anti-apoptotic effect of rhEPO-producing fibroblasts was evaluated by co-culture with rat neonatal cardiomyocytes exposed to H2O2-induced oxidative stress. Annexin V/PI assay and DAPI staining showed that compared with control, rhEPO forced expression markedly attenuated apoptosis and improved survival of cultured cardiomyocytes. To test the effect of rhEPO on the infarcted myocardium, Sprague-Dawley rats were subjected to permanent coronary artery occlusion, and rhEPO-producing fibroblasts, non-transduced fibroblasts, or saline, were injected into the scar tissue seven days after infarction. One month later, immunostaining identified rhEPO expression in the implanted engineered cells but not in controls. Compared with non-transduced fibroblasts or saline injection, implanted rhEPO-producing fibroblasts promoted vascularization in the scar, and prevented cell apoptosis. By two-dimensional echocardiography and postmortem morphometry, transplanted EPO-engineered fibroblasts did not prevent left ventricular (LV dysfunction and adverse LV remodeling 5 and 9 weeks after MI. Conclusion In situ expression of rhEPO enhances vascularization and reduces cell apoptosis in the infarcted myocardium. However, local EPO therapy is insufficient for functional improvement after MI in rat.

  2. Neurobehavioral and respiratory findings in jet engine repair workers: A comparison of exposed and unexposed volunteers.

    Science.gov (United States)

    Kilburn, K H

    1999-04-01

    Workers repairing jet engines had respiratory, rheumatic, and neurobehavioral symptoms. They had welded and ground stainless steel parts using hard metal tools and cleaned metal with chlorinated and fluorinated organic solvents. We compared 154 workers and 112 unexposed subjects, all volunteers of similar ages and with similar educational levels, for abnormalities on chest radiographs, spirometric measurements, and questionnaires. Also appraised were performance of reaction time, balance, blink reflex latency, color discrimination, Culture Fair, vocabulary, slotted pegboard, trail making A and B, profile of mood states (POMS), and frequencies of 35 symptoms. Compared to unexposed subjects, workers had significantly more respiratory symptoms but no differences in pulmonary function. They had significantly prolonged simple and choice reaction time (P<0.0001), and abnormal balance with eyes open and eyes closed (P<0. 0001), and abnormal color discrimination. Blink reflex latency was abnormal in both exposed workers and in local unexposed compared to other reference groups. Focus of the inquiry on lung disease helped ensure that for neurobehavioral tests confounding factors were minimal and known biases were small. We tentatively attribute the neurobehavioral impairments and increased symptom frequencies to chlorinated solvent exposure. Excessive respiratory symptoms are attributed to welding stainless steel combined with cigarette smoking. Specifically, manganese exposure may have affected the respiratory and the central nervous systems.

  3. Validation of the Algorithms for Depot Exchangeable Repair and Modification Costs for NSNS and Engines for the Component Support Cost System (D160B).

    Science.gov (United States)

    2014-09-26

    IDENTIFICATION OI 03 NOMENCLATURE . ITEM 012 03 PRICE. STANDARD INVENTORY 013 03 CODE. WEAPON SYSTEM SUPPORT 014 06 CODE. WEAPON SYSTEM SUPPORT. POSITIONS I TO...calculation of standard depot repair prices ( sales prices). Various knowledgeable Air Force personnel have noted that it is not unusual for an engine to be both...cost elements not used in calculation of standard depot repair prices (" sales prices"). ISI affirms the congruence of the definitions of repair prices as

  4. Robot based three-dimensional welding for jet engine blade repair and rapid prototyping of small components

    Science.gov (United States)

    Thukaram, Santosh Kumar

    Aero engines are made up of a large number of blades which are subject to wear and damage. They are expensive and must be repaired wherever possible. Engines also have small components which are required in small numbers that need to be developed rapidly. The first part of this research work focuses on developing a robust automated blade repair method using robotic welding. Optimal weld parameters were developed for build-up of edges having different thicknesses. Samples with varying Current and varying travel speed were produced and their micro hardness values were compared. Blade profiles were welded upon. The second part involves a methodology for producing small components using rapid prototyping (RP) techniques. This part involves use of 3D robotic welding for layered manufacturing. Tensile samples produced using the metal RP method were tested and results were found to be well above the minimum cast specifications for the given material.

  5. Prediction of cold start hydrocarbon emissions of air cooled two wheeler spark ignition engines by simple fuzzy logic simulation

    Directory of Open Access Journals (Sweden)

    Samuel Raja Ayyanan

    2014-01-01

    Full Text Available The cold start hydrocarbon emission from the increasing population of two wheelers in countries like India is one of the research issues to be addressed. This work describes the prediction of cold start hydrocarbon emissions from air cooled spark ignition engines through fuzzy logic technique. Hydrocarbon emissions were experimentally measured from test engines of different cubic capacity, at different lubricating oil temperature and at different idling speeds with and without secondary air supply in exhaust. The experimental data were used as input for modeling average hydrocarbon emissions for 180 seconds counted from cold start and warm start of gasoline bike engines. In fuzzy logic simulation, member functions were assigned for input variables (cubic capacity and idling rpm and output variables (average hydrocarbon emission for first 180 seconds at cold start and warm start. The knowledge based rules were adopted from the analyzed experimental data and separate simulations were carried out for predicting hydrocarbon emissions from engines equipped with and without secondary air supply. The simulation yielded the average hydrocarbon emissions of air cooled gasoline engine for a set of given input data with accuracy over 90%.

  6. Replace the Carburetor Diaphragm. Pulsa-Jet Style with Automatic Choke. Fuel System. Student Manual 2. Small Engine Repair Series. First Edition.

    Science.gov (United States)

    Hill, Pamela

    This student manual, part of a small-engine repair series on servicing fuel systems, is designed for use by special needs students in Texas. The manual explains in pictures and short sentences, written on a low reading level, the job of replacing carburetor diaphragms. Along with the steps of this repair job, specific safety and caution…

  7. EFFECT OF GASOLINE - ETHANOL BLENDS ON PERFORMANCE AND EMISSION CHARACTERISTICS OF A SINGLE CYLINDER AIR COOLED MOTOR BIKE SI ENGINE

    Directory of Open Access Journals (Sweden)

    A. SAMUEL RAJA

    2015-12-01

    Full Text Available This paper investigates the effect of using gasoline-ethanol (GE blends on performance and exhaust emission of a four stroke 150 cc single cylinder air cooled spark ignition (SI engine, without any modifications. Experiments were conducted at part load and different engine speeds ranging from 3000 to 5000 rpm, without and with catalytic converter. Ethanol content was varied from 5 percentage to 20 percentage by volume and four different blends (E5, E10, E15 and E20 were tested. Fuel consumption, engine speed, air fuel ratio, exhaust gas temperature and exhaust emissions were measured during each experiment. Brake thermal efficiency (ηb,th, volumetric efficiency (ηvol, brake specific fuel consumption (BSFC and excess air factor were calculated for each test run. Brake specific fuel consumption, volumetric efficiency and excess air factor increased with ethanol percentage in the blend. Carbon monoxide (CO, hydrocarbon (HC and oxides of nitrogen (NOx emissions decreased with blends.

  8. Low-Cost Manufacturing Technique for Advanced Regenerative Cooling for In-Space Cryogenic Engines Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of the proposed effort is to use selective laser melting (SLM, an additive manufacturing technique) to manufacture a hot fire-capable, water-cooled spool...

  9. Mesenchymal stem cells delivered in a microsphere-based engineered skin contribute to cutaneous wound healing and sweat gland repair.

    Science.gov (United States)

    Huang, Sha; Lu, Gang; Wu, Yan; Jirigala, Enhe; Xu, Yongan; Ma, Kui; Fu, Xiaobing

    2012-04-01

    Bone-marrow-derived mesenchymal stem cells (BM-MSCs) can contribute to wound healing after skin injury. However, the role of BM-MSCs on repairing skin appendages in renewal tissues is incompletely explored. Moreover, most preclinical studies suggest that the therapeutic effects afforded by BM-MSCs transplantation are short-lived and relatively unstable. To assess whether engrafted bone-marrow-derived mesenchymal stem cells via a delivery system can participate in cutaneous wound healing and sweat-gland repair in mice. For safe and effective delivery of BM-MSCs to wounds, epidermal growth factor (EGF) microspheres were firstly developed to both support cells and maintain appropriate stimuli, then cell-seeded microspheres were incorporated with biomimetic scaffolds and thus fabricated an engineered skin construct with epithelial differentiation and proliferative potential. The applied efficacy was examined by implanting them into excisional wounds on both back and paws of hind legs in mice. After 3 weeks, BM-MSC-engineered skin (EGF loaded) treated wounds exhibited accelerated healing with increased re-epithelialization rates and less skin contraction. Furthermore, histological and immunofluorescence staining analysis revealed sweat glands-like structures became more apparent in BM-MSC-engineered skin (EGF loaded) treated wounds but the number of implanted BM-MSCs were decreased gradually in later phases of healing progression. Our study suggests that BM-MSCs delivered by this EGF microspheres-based engineered skin model may be a promising strategy to repair sweat glands and improve cutaneous wound healing after injury and success in this study might provide a potential benefit for BM-MSCs administration clinically. Copyright © 2012 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  10. 汽车发动机的维修与保养分析%Repair and maintenance of automobile engine

    Institute of Scientific and Technical Information of China (English)

    陈航

    2013-01-01

    With the continued growth of the national economy, people's living standards improve, the automotive in-dustry significantly increased the pace of development. Car engine is a core part of automotive parts, but also to start the car the only member which is not only to ensure quality performance guarantee safe driving cars, but also extend vehicle life. Therefore, to do routine maintenance and repair car engine work is very important. Articles will be corporate engine repair and maintenance work to discuss, to understand the basic principles of automotive engine, and its routine mainte-nance and repair to propose effective countermeasures.%随着国民经济持续增长,人们生活水平不断提高,汽车工业的发展速度显著提高。汽车发动机是汽车零部件的核心部分,也是启动汽车的唯一部件,其质量性能保障不仅保证汽车安全驾驶,还延长汽车使用寿命。因此,做好汽车发动机日常维修与保养工作十分重要。文章将对企业发动机的维修与保养工作展开讨论,了解汽车发动机的基本原理,并对其日常保养与维修提出有效的对策。

  11. Bringing Engineering Design into High School Science Classrooms: The Heating/Cooling Unit

    Science.gov (United States)

    Apedoe, Xornam S.; Reynolds, Birdy; Ellefson, Michelle R.; Schunn, Christian D.

    2008-01-01

    Infusing engineering design projects in K-12 settings can promote interest and attract a wide range of students to engineering careers. However, the current climate of high-stakes testing and accountability to standards leaves little room to incorporate engineering design into K-12 classrooms. We argue that design-based learning, the combination…

  12. Effects of Nozzle Scale, Total Temperature and an Afterburner on Jet Noise from a Pre-Cooled Turbojet Engine

    Science.gov (United States)

    Araki, Mikiya; Sano, Takayuki; Fukuda, Masayuki; Kojima, Takayuki; Taguchi, Hideyuki; Nishida, Shunsuke; Imamura, Osamu; Shiga, Seiichi; Tsue, Mitsuhiro

    Effects of nozzle scale, total temperature, and an afterburner on jet noise characteristics from a pre-cooled turbojet engine are investigated experimentally. In JAXA (Japan Aerospace Exploration Agency), a pre-cooled turbojet engine for an HST (Hypersonic transport) is under development. In the present study, 1.0%- and 2.4%-scaled models of the rectangular plug nozzle (Nozzles I and II) are manufactured, and the jet noise characteristics are investigated under a wide range of total temperatures. For Nozzle I, no air-heater is utilized and the total temperature is 290K. For Nozzle II, a pebble heater and an afterburner (AB) are utilized upstream of the nozzle model, and the total temperature is varied from 520K (pebble heater) to 1540K (pebble heater + AB). The total pressure is set at 0.27 and 0.30MPa(a) for both nozzle models. Jet noise is measured using a high-frequency microphone set at 135 deg from the engine inlet, and normalized jet noise spectra are obtained based on AUjn law and Helmholtz number. For cases without afterburner, the normalized spectra agrees well regardless of the nozzle scale and total temperature where the velocity index lies from n = 7.7 to 9.2, and the correlation factor between the two facilities is shown to be about 1dB. For the case with afterburner, the normalized spectrum does not agree with other conditions where the velocity index n seems to be about 4.

  13. Research on the possibility of restoring blades while repairing gas turbine engines parts by selective laser melting

    Science.gov (United States)

    Smelov, V. G.; Sotov, A. V.; Agapovichev, A. V.

    2016-07-01

    We study the possibility of restoring the blades of chromium-nickel materials for the repair of parts of gas turbine engines using selective laser melting technology. The stages of preparation of the items to repair and reconditioning are considered in detail, the algorithm of the recovery process to a 3D machine has been developed. Chemical analysis of the raw material and facing material has been performed. Maps of distribution of chemical elements in the fusion zone of the starting material with the surfacing material have been acquired. In order to study the nature of alloying materials fractographic analysis of the places of fusion was performed. A map of distribution of chemical elements in the fusion zone was obtained.

  14. Pore-Engineered Metal–Organic Frameworks with Excellent Adsorption of Water and Fluorocarbon Refrigerant for Cooling Applications

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Jian [Physical; Vemuri, Rama S. [Energy; Estevez, Luis [Energy; Koech, Phillip K. [Energy; Varga, Tamas [Environmental; Camaioni, Donald M. [Physical; Blake, Thomas A. [Physical; McGrail, B. Peter [Energy; Motkuri, Radha Kishan [Energy

    2017-07-20

    Metal–organic frameworks (MOFs) are found to be promising sorbents for adsorption cooling applications. Using organic ligands with 1, 2, and 3 phenylene rings, we construct moisture-stable Ni-MOF-74 members with adjustable pore apertures. These pore-engineered materials exhibit excellent sorption capabilities towards water and fluorocarbons. The adsorption patterns for these materials differ significantly and are attributed to variances in the hydrophobic/hydrophilic pore character, associated with differences in pore size. Complementary ex situ characterizations and in situ FTIR spectra are deployed to understand the correlations between the mechanisms of gas loadings and the pore environment of the MOFs.

  15. Industrial cooling for mechanical engineering - requirements and current developments; Maschinenkuehlungen Anforderungen und aktuelle Tendenzen

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, K.P. [Kulmbacher Klimageraete-Werke GmbH, Geschaeftsbereich Riedel Kaeltetechnik (Germany)

    2002-06-01

    A special field of refrigeration is the cooling of technological processes. Common refrigeration technology mostly operates at lower evaporation temperatures and with shorter operating times, however the cooling of tool machines often demands higher temperatures and long-term operating times. This requires a special design and calculation of the components. (orig.) [German] Ein besonderes Einsatzgebiet der Kaeltetechnik stellt die Kuehlung technologischer Prozesse dar. Waehrend in der ueblichen Kaeltetechnik niedrige Verdampfungstemperaturen und relativ geringe Nutzungszeiten dominieren, sind bei der Waermeabfuhr von Maschinen haeufig hoehere Temperaturen und lange Betriebszeiten zu realisieren. Dies erfordert eine spezielle Auslegung der Komponenten. (orig.)

  16. Engineering review of the core support structure of the Gas Cooled Fast Breeder Reactor

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-09-01

    The review of the core support structure of the gas cooled fast breeder reactor (GCFR) covered such areas as the design criteria, the design and analysis of the concepts, the development plan, and the projected manufacturing costs. Recommendations are provided to establish a basis for future work on the GCFR core support structure.

  17. A study of optimum cowl shapes and flow port locations for minimum drag with effective engine cooling, volume 2

    Science.gov (United States)

    Fox, S. R.; Smetana, F. O.

    1980-01-01

    The listings, user's instructions, sample inputs, and sample outputs of two computer programs which are especially useful in obtaining an approximate solution of the viscous flow over an arbitrary nonlifting three dimensional body are provided. The first program performs a potential flow solution by a well known panel method and readjusts this initial solution to account for the effects of the boundary layer displacement thickness, a nonuniform but unidirectional onset flow field, and the presence of air intakes and exhausts. The second program is effectually a geometry package which allows the user to change or refine the shape of a body to satisfy particular needs without a significant amount of human intervention. An effort to reduce the cruise drag of light aircraft through an analytical study of the contributions to the drag arising from the engine cowl shape and the foward fuselage area and also that resulting from the cooling air mass flowing through intake and exhaust sites on the nacelle is presented. The programs may be effectively used to determine the appropriate body modifications or flow port locations to reduce the cruise drag as well as to provide sufficient air flow for cooling the engine.

  18. Three dimensional simulation of nucleate boiling heat and mass transfer in cooling passages of internal combustion engines

    Science.gov (United States)

    Mehdipour, R.; Baniamerian, Z.; Delauré, Y.

    2016-05-01

    An accurate knowledge of heat transfer and temperature distribution in vehicle engines is essential to have a good management of heat transfer performance in combustion engines. This may be achieved by numerical simulation of flow through the engine cooling passages; but the task becomes particularly challenging when boiling occurs. Neglecting two phase flow processes in the simulation would however result in significant inaccuracy in the predictions. In this study a three dimensional numerical model is proposed using Fluent 6.3 to simulate heat transfer of fluid flowing through channels of conventional size. Results of the present theoretical and numerical model are then compared with some empirical results. For high fluid flow velocities, departure between experimental and numerical results is about 9 %, while for lower velocity conditions, the model inaccuracy increases to 18 %. One of the outstanding capabilities of the present model, beside its ability to simulate two phase fluid flow and heat transfer in three dimensions, is the prediction of the location of bubble formation and condensation which can be a key issue in the evaluation of the engine performance and thermal stresses.

  19. Tissue engineering repair for femoral head necrosis%股骨头坏死的组织工程修复

    Institute of Scientific and Technical Information of China (English)

    龙腾河; 崔惠勤; 李涛

    2012-01-01

    BACKGROUND: The development of tissue engineering technique changed the manner for treating bone defect. Because bone tissues are reproducible, more and more medical investigators paid a great attention on application of tissue engineering in treatment of femoral head necrosis.OBJECTIVE: To summarize the tissue engineering repair manner of femoral head necrosis, and to explore the perspective of regenerative medicine in bone tissue engineering.METHODS: We retrieved articles regarding tissue engineering techniques in repair of femoral head necrosis from aspects of frontier fields of tissue engineering, including stem cells, tissue construction and biomechanics, orthopedics biomaterial, artificial prosthetic replacement, bone graft transplantation published from January 2000 to December 2011. Repetitive or Meta analysis articles were excluded. A total of 30 representative articles were analyzed.RESULTS AND CONCLUSION: With the progression of regenerative medicine, tissue engineering technique had been widely used in repair of femoral head necrosis, containing stem cells from different sources transplantation for treating femoral head necrosis, inflammatory factor and femora head necrosis, construction and biomechanical analysis of finite element model of femoral head necrosis, varied giant molecular organism bone scaffold in repair of femoral head necrosis, artificial bone implantation and artificial hip joint replacement. However, present tissue engineering in treatment of femoral head necrosis is still in animal experiment and empirical treatment levels.%背景 随着组织工程学技术的发展,改变了治疗骨缺损的传统治疗模式.由于骨组织是可再生组织,医学研究者们越来越重视组织工程在股骨头坏死治疗中的应用.目的 总结股骨头坏死的组织工程修复手段,探索再生医学在骨组织工程领域的医用前景.方法 从组织工程医学关注的几个前沿领域,包括 "干细胞、组织构建与生物

  20. Cooling phonons with phonons: Acoustic reservoir engineering with silicon-vacancy centers in diamond

    Science.gov (United States)

    Kepesidis, K. V.; Lemonde, M.-A.; Norambuena, A.; Maze, J. R.; Rabl, P.

    2016-12-01

    We study a setup where a single negatively-charged silicon-vacancy center in diamond is magnetically coupled to a low-frequency mechanical bending mode and via strain to the high-frequency phonon continuum of a semiclamped diamond beam. We show that under appropriate microwave driving conditions, this setup can be used to induce a laser-cooling-like effect for the low-frequency mechanical vibrations, where the high-frequency longitudinal compression modes of the beam serve as an intrinsic low-temperature reservoir. We evaluate the experimental conditions under which cooling close to the quantum ground state can be achieved and describe an extended scheme for the preparation of a stationary entangled state between two mechanical modes. By relying on intrinsic properties of the mechanical beam only, this approach offers an interesting alternative for quantum manipulation schemes of mechanical systems, where otherwise efficient optomechanical interactions are not available.

  1. Detection of abnormalities in the superficial zone of cartilage repaired using a tissue engineered construct derived from synovial stem cells.

    Science.gov (United States)

    Ando, Wataru; Fujie, Hiromichi; Moriguchi, Yu; Nansai, Ryosuke; Shimomura, Kazunori; Hart, David A; Yoshikawa, Hideki; Nakamura, Norimasa

    2012-09-28

    The present study investigated the surface structure and mechanical properties of repair cartilage generated from a tissue engineered construct (TEC) derived from synovial mesenchymal stem cells at six months post-implantation compared to those of uninjured cartilage. TEC-mediated repair tissue was cartilaginous with Safranin O staining, and had comparable macro-scale compressive properties with uninjured cartilage. However, morphological assessments revealed that the superficial zone of TEC-mediated tissue was more fibrocartilage-like, in contrast to the middle or deep zones that were more hyaline cartilage-like with Safranin O staining. Histological scoring of the TEC-mediated tissue was significantly lower in the superficial zone than in the middle and deep zones. Scanning electron microscopy showed a thick tangential bundle of collagen fibres at the most superficial layer of uninjured cartilage, while no corresponding structure was detected at the surface of TEC-mediated tissue. Immunohistochemical analysis revealed that PRG4 was localised in the superficial area of uninjured cartilage, as well as the TEC-mediated tissue. Friction testing showed that the lubrication properties of the two tissues was similar, however, micro-indentation analysis revealed that the surface stiffness of the TEC-repair tissue was significantly lower than that of uninjured cartilage. Permeability testing indicated that the TEC-mediated tissue exhibited lower water retaining capacity than did uninjured cartilage, specifically at the superficial zone. Thus, TEC-mediated tissue exhibited compromised mechanical properties at the superficial zone, properties which need improvement in the future for maintenance of long term repair cartilage integrity.

  2. Detection of abnormalities in the superficial zone of cartilage repaired using a tissue engineered construct derived from synovial stem cells

    Directory of Open Access Journals (Sweden)

    W Ando

    2012-09-01

    Full Text Available The present study investigated the surface structure and mechanical properties of repair cartilage generated from a tissue engineered construct (TEC derived from synovial mesenchymal stem cells at six months post-implantation compared to those of uninjured cartilage. TEC-mediated repair tissue was cartilaginous with Safranin O staining, and had comparable macro-scale compressive properties with uninjured cartilage. However, morphological assessments revealed that the superficial zone of TEC-mediated tissue was more fibrocartilage-like, in contrast to the middle or deep zones that were more hyaline cartilage-like with Safranin O staining. Histological scoring of the TEC-mediated tissue was significantly lower in the superficial zone than in the middle and deep zones. Scanning electron microscopy showed a thick tangential bundle of collagen fibres at the most superficial layer of uninjured cartilage, while no corresponding structure was detected at the surface of TEC-mediated tissue. Immunohistochemical analysis revealed that PRG4 was localised in the superficial area of uninjured cartilage, as well as the TEC-mediated tissue. Friction testing showed that the lubrication properties of the two tissues was similar, however, micro-indentation analysis revealed that the surface stiffness of the TEC-repair tissue was significantly lower than that of uninjured cartilage. Permeability testing indicated that the TEC-mediated tissue exhibited lower water retaining capacity than did uninjured cartilage, specifically at the superficial zone. Thus, TEC-mediated tissue exhibited compromised mechanical properties at the superficial zone, properties which need improvement in the future for maintenance of long term repair cartilage integrity.

  3. Overall Effectiveness Measurement at Engine Temperatures with Reactive Film Cooling and Surface Curvature

    Science.gov (United States)

    2015-03-26

    Da = Damkohler number ( ℎ ) DR = density ratio F = Fahrenheit FCR = film cooling rig H* = non-dimensional fuel enthalpy h...the objective of a film layer is to remain 2 attached to the blade surface, any flame produced by a reaction between the coolant and the...making reactions likely Figure 2-5 shows the predicted temperature profile on a portion of a hybrid vane. The combustion occurs in the cavity on the top

  4. Heat engineering characteristics of the radiator for effective electronic equipment cooling systems

    Directory of Open Access Journals (Sweden)

    Rudenko A. I.

    2011-06-01

    Full Text Available The article presents the results of heat transfer charac-teristics research of the radiator on basis of a heat pipe for cooling of personal computer elements. It is determined that using acetone and ethanol as heat carriers under heat flow density q4·104 W/m2 is preferable. It is shown that the introduced radiators are considerably more effective than the radiators of conventional design with flat heat exchange surface with a rectangle plate fin.

  5. Tandem repeat modification during double-strand break repair induced by an engineered TAL effector nuclease in zebrafish genome.

    Directory of Open Access Journals (Sweden)

    Wanxu Huang

    Full Text Available Tandem repeats (TRs are abundant and widely distributed in eukaryotic genomes. TRs are thought to have various functions in gene transcription, DNA methylation, nucleosome position and chromatin organization. Variation of repeat units in the genome is observed in association with a number of diseases, such as Fragile X Syndrome, Huntington's disease and Friedreich's ataxia. However, the underlying mechanisms involved are poorly understood, largely owing to the technical limitations in modification of TRs at definite sites in the genome in vivo. Transcription activator-like effector nucleases (TALENs are widely used in recent years in gene targeting for their specific binding to target sequences when engineered in vitro. Here, we show that the repair of a double-strand break (DSB induced by TALENs adjacent to a TR can produce serial types of mutations in the TR region. Sequencing analysis revealed that there are three types of mutations induced by the DSB repair, including indels only within the TR region or within the flanking TALEN target region or simutaneously within both regions. Therefore, desired TR mutant types can be conveniently obtained by using engineered TALENs. These results demonstrate that TALENs can serve as a convenient tool for modifying TRs in the genome in studying the functions of TRs.

  6. SMA foil-based elastocaloric cooling: from material behavior to device engineering

    Science.gov (United States)

    Bruederlin, F.; Ossmer, H.; Wendler, F.; Miyazaki, S.; Kohl, M.

    2017-10-01

    The elastocaloric effect associated with the stress-induced first order phase transformation in pseudoelastic shape memory alloy (SMA) films and foils is of special interest for cooling applications on a miniature scale enabling fast heat transfer and high cycling frequencies as well as tunable transformation temperatures. The focus is on TiNi-based materials having the potential to meet the various challenges associated with elastocaloric cooling including large adiabatic temperature change and ultra-low fatigue. The evolution of strain and temperature bands during tensile load cycling is investigated with respect to strain and strain-rate by in situ digital image correlation and infrared thermography with a spatial resolution in the order of 25 µm. Major design issues and challenges in fabrication of SMA film-based elastocaloric cooling devices are discussed including the efficiency of heat transfer as well as force recovery to enhance the coefficient of performance (COP) on the system level. Advanced demonstrators show a temperature span of 13 °C after 30 s, while the COP of the overall device reaches almost 10% of Carnot efficiency.

  7. Stagnation region gas film cooling: Spanwise angled injection from multiple rows of holes. [gas turbine engines

    Science.gov (United States)

    Luckey, D. W.; Lecuyer, M. R.

    1981-01-01

    The stagnation region of a cylinder in a cross flow was used in experiments conducted with both a single row and multiple rows of spanwise angled (25 deg) coolant holes for a range of the coolant blowing ratio with a freestream to wall temperature ratio approximately equal to 1.7 and R(eD) = 90,000. Data from local heat flux measurements are presented for injection from a single row located at 5 deg, 22.9 deg, 40.8 deg, 58.7 deg from stagnation using a hole spacing ratio of S/d(o) = 5 and 10. Three multiple row configurations were also investigated. Data are presented for a uniform blowing distribution and for a nonuniform blowing distribution simulating a plenum supply. The data for local Stanton Number reduction demonstrated a lack of lateral spreading by the coolant jets. Heat flux levels larger than those without film cooling were observed directly behind the coolant holes as the blowing ratio exceeded a particular value. The data were spanwise averaged to illustrate the influence of injection location, blowing ratio and hole spacing. The large values of blowing ratio for the blowing distribution simulating a plenum supply resulted in heat flux levels behind the holes in excess of the values without film cooling. An increase in freestream turbulence intensity from 4.4 to 9.5 percent had a negligible effect on the film cooling performance.

  8. Regeneratively-Cooled, Turbopump-Fed, LOX/Methane Lunar Ascent Engines Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To-date, the realization of small-scale, high-performance liquid bipropellant rocket engines for lunar and other planetary ascent vehicles has largely been limited...

  9. Regeneratively-Cooled, Turbopump-Fed, Small-Scale Cryogenic Rocket Engines Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To-date, the realization of small-scale, high-performance liquid bipropellant rocket engines has largely been limited by the inability to operate at high chamber...

  10. Study of two-phase turbine engine for solar space cooling. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Amend, W.E.

    1980-08-01

    Detailed mathematical description of two promising Biphase refrigeration cycles were developed and programmed on the computer (all known first-order irreversibilities were accounted for). Extensive parameter sweeps were made to identify the most effective working-fluid combinations and to determine the sensitivity of cycle-performance levels. A Cycle configuration was established for a nominal 3-ton air cooled refrigeration system and the design parameters were determined from the computer code. A series of fluid compatibility tests were run to weed out potential fluid combinations that are reactive.

  11. Spin based heat engine: demonstration of multiple rounds of algorithmic cooling.

    Science.gov (United States)

    Ryan, C A; Moussa, O; Baugh, J; Laflamme, R

    2008-04-11

    We experimentally demonstrate multiple rounds of heat-bath algorithmic cooling in a 3 qubit solid-state nuclear magnetic resonance quantum information processor. By pumping entropy into a heat bath, we are able to surpass the closed system limit of the Shannon bound and purify a single qubit to 1.69 times the heat-bath polarization. The algorithm combines both high fidelity coherent control and a deliberate interaction with the environment. Given this level of quantum control in systems with larger reset polarizations, nearly pure qubits should be achievable.

  12. A Cooling System for an Automobile Based on Vapour Absorption Refrigeration Cycle Using Waste Heat of an Engine.

    Directory of Open Access Journals (Sweden)

    Satish K. Maurya

    2014-03-01

    Full Text Available Now a days the air conditioning system of cars is mainly uses “Vapour Compression Refrigerant System” (VCRS which absorbs and removes heat from the interior of the car that is the space to be cooled and rejects the heat to atmosphere. In vapour compression refrigerant system, the system utilizes power from engine shaft as the input power to drive the compressor of the refrigeration system, hence the engine has to produce extra work to run the compressor of the refrigerating system utilizing extra amount of fuel. This loss of power of the vehicle for refrigeration can be neglected by utilizing another refrigeration system i.e. a “Vapour Absorption Refrigerant System”. As well known thing about VAS that these machines required low grade energy for operation. Hence in such types of system, a physicochemical process replaces the mechanical process of the Vapour Compression Refrigerant System by using energy in the form of heat rather than mechanical work. This heat obtained from the exhaust of high power internal combustion engines.

  13. Effect of cooled EGR on performance and exhaust gas emissions in EFI spark ignition engine fueled by gasoline and wet methanol blends

    Science.gov (United States)

    Rohadi, Heru; Syaiful, Bae, Myung-Whan

    2016-06-01

    Fuel needs, especially the transport sector is still dominated by fossil fuels which are non-renewable. However, oil reserves are very limited. Furthermore, the hazardous components produced by internal combustion engine forces many researchers to consider with alternative fuel which is environmental friendly and renewable sources. Therefore, this study intends to investigate the impact of cooled EGR on the performance and exhaust gas emissions in the gasoline engine fueled by gasoline and wet methanol blends. The percentage of wet methanol blended with gasoline is in the range of 5 to 15% in a volume base. The experiment was performed at the variation of engine speeds from 2500 to 4000 rpm with 500 intervals. The re-circulated exhaust gasses into combustion chamber was 5%. The experiment was performed at the constant engine speed. The results show that the use of cooled EGR with wet methanol of 10% increases the brake torque up to 21.3%. The brake thermal efficiency increases approximately 39.6% using cooled EGR in the case of the engine fueled by 15% wet methanol. Brake specific fuel consumption for the engine using EGR fueled by 10% wet methanol decreases up to 23% at the engine speed of 2500 rpm. The reduction of CO, O2 and HC emissions was found, while CO2 increases.

  14. A study of optimum cowl shapes and flow port locations for minimum drag with effective engine cooling, volume 1

    Science.gov (United States)

    Fox, S. R.; Smetana, F. O.

    1980-01-01

    The contributions to the cruise drag of light aircraft arising from the shape of the engine cowl and the forward fuselage area and also that resulting from the cooling air mass flow through intake and exhaust sites on the nacelle were analyzed. The methods employed for the calculation of the potential flow about an arbitrary three dimensional body are described with modifications to include the effects of boundary layer displacement thickness, a nonuniform onset flow field (such as that due to a rotating propeller), and the presence of air intakes and exhausts. A simple, reliable, largely automated scheme to better define or change the shape of a body is also presented. A technique was developed which can yield physically acceptable skin friction and pressure drag coefficients for isolated light aircraft bodies. For test cases on a blunt nose Cessna 182 fuselage, the technique predicted drag reductions as much as 28.5% by body recontouring and proper placements and sizing of the cooling air intakes and exhausts.

  15. Preliminary structural design and thermo-mechanical analysis of helium cooled solid breeder blanket for Chinese Fusion Engineering Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Li, Min; Chen, Hongli, E-mail: hlchen1@ustc.edu.cn; Zhou, Guangming; Liu, Qianwen; Wang, Shuai; Lv, Zhongliang; Ye, Minyou

    2015-02-15

    Highlights: • A helium cooled solid breeder blanket module was designed for CFETR. • Multilayer U-shaped pebble beds were adopted in the blanket module. • Thermal and thermo-mechanical analyses were carried out under normal operating conditions. • The analysis results were found to be acceptable. - Abstract: With the aim to bridge the R&D gap between ITER and fusion power plant, the Chinese Fusion Engineering Test Reactor (CFETR) was proposed to be built in China. The mission of CFETR is to address the essential R&D issues for achieving practical fusion energy. Its blanket is required to be tritium self-sufficient. In this paper, a helium cooled solid breeder blanket adopting multilayer U-shaped pebble beds was designed and analyzed. Thermo-mechanical analysis of the first wall and side wall combined with breeder unit was carried out for normal operating steady state conditions. The results showed that the maximum temperatures of the structural material, neutron multiplier and tritium breeder pebble beds are 523 °C, 558 °C and 787 °C, respectively, which are below the corresponding limits of 550 °C, 650 °C and 920 °C. The maximum equivalent stress of the structure is under the allowable value with a margin about 14.5%.

  16. Integral cooling system for a jet engine integral starter/generator and the like

    Energy Technology Data Exchange (ETDEWEB)

    Yerkes, K.L.

    1993-08-31

    A cooling system is described, comprising: (a) a shroud for providing a flow path for a coolant; (b) a plurality of off-axis thermosyphons positioned inside the shroud, each thermosyphon having a condenser section extending into the coolant flow path and each thermosyphon also having an evaporator section, an inside wall and a longitudinal axis; (c) fins attached to each condenser section, wherein the fins are oriented so that they will draw coolant through the shroud; and (d) a wick having a fixed shape partially covering the inside wall of each enclosure, wherein a cross-section of each wick is asymmetrical about the respective longitudinal axis of each thermosyphon and wherein each wick has generally the shape a liquid working fluid would assume while the plurality of thermosyphons were rotating.

  17. Dark matter merging induced turbulence as an efficient engine for gas cooling

    Science.gov (United States)

    Prieto, Joaquin; Jimenez, Raul; Martí, Jose

    2012-02-01

    We have performed a cosmological numerical simulation of primordial baryonic gas collapsing on to a 3 × 107 M⊙ dark matter (DM) halo. We show that the large scale baryonic accretion process and the merger of few ˜ 106 M⊙ DM haloes, triggered by the gravitational potential of the biggest halo, are enough to create supersonic (?) shocks and develop a turbulent environment. In this scenario, the post-shocked regions are able to produce both H2 and deuterated H2 molecules very efficiently, reaching maximum abundances of ? and nHD˜ few × 10-6 nH, enough to cool the gas below 100 K in some regions. The kinetic energy spectrum of the turbulent primordial gas is close to a Burgers spectrum, ?, which could favour the formation of low-mass primordial stars. The solenoidal-to-total kinetic energy ratio is 0.65 ≲Rk≲ 0.7 for a wide range of wavenumbers; this value is close to the Rk≈ 2/3 natural equipartition energy value of a random turbulent flow. In this way, turbulence and molecular cooling seem to work together in order to produce potential star formation regions of cold dense gas in primordial environments. We conclude that both the mergers and the collapse process on to the main DM halo provide enough energy to develop supersonic turbulence which favours the molecular coolant formation: this mechanism, which could be universal and the main route towards the formation of the first galaxies, is able to create potential star-forming regions at high redshift.

  18. Minimum Specific Fuel Consumption of a Liquid-Cooled Multicylinder Aircraft Engine as Affected by Compression Ratio and Engine Operating Conditions

    Science.gov (United States)

    Brun, Rinaldo J.; Feder, Melvin S.; Harries, Myron L.

    1947-01-01

    An investigation was conducted on a 12-cylinder V-type liquid-cooled aircraft engine of 1710-cubic-inch displacement to determine the minimum specific fuel consumption at constant cruising engine speed and compression ratios of 6.65, 7.93, and 9.68. At each compression ratio, the effect.of the following variables was investigated at manifold pressures of 28, 34, 40, and 50 inches of mercury absolute: temperature of the inlet-air to the auxiliary-stage supercharger, fuel-air ratio, and spark advance. Standard sea-level atmospheric pressure was maintained at the auxiliary-stage supercharger inlet and the exhaust pressure was atmospheric. Advancing the spark timing from 34 deg and 28 deg B.T.C. (exhaust and intake, respectively) to 42 deg and 36 deg B.T.C. at a compression ratio of 6.65 resulted in a decrease of approximately 3 percent in brake specific fuel consumption. Further decreases in brake specific fuel consumption of 10.5 to 14.1 percent (depending on power level) were observed as the compression ratio was increased from 6.65 to 9.68, maintaining at each compression ratio the spark advance required for maximum torque at a fuel-air ratio of 0.06. This increase in compression ratio with a power output of 0.585 horsepower per cubic inch required a change from . a fuel- lend of 6-percent triptane with 94-percent 68--R fuel at a compression ratio of 6.65 to a fuel blend of 58-percent, triptane with 42-percent 28-R fuel at a compression ratio of 9.68 to provide for knock-free engine operation. As an aid in the evaluation of engine mechanical endurance, peak cylinder pressures were measured on a single-cylinder engine at several operating conditions. Peak cylinder pressures of 1900 pounds per square inch can be expected at a compression ratio of 9.68 and an indicated mean effective pressure of 320 pounds per square inch. The engine durability was considerably reduced at these conditions.

  19. Research on laser melting-alloying combined strengthening of the camshaft of air-cooled diesel engine

    Science.gov (United States)

    Liu, Wenjin; Zhong, Minlin; Zhao, Haiyun; Zhang, Hongjun; Zhang, Weimin; Huang, Guoqing

    1996-04-01

    This paper reported the research results on 3 kw cw CO2 laser melting-alloying combined strengthening of the camshaft of air-cooled diesel engine used in the desert oil field. The 45 steel camshaft was pretreated with the conventional quenching and high temperature tempering. A focused laser beam with power density 1.5 - 1.7 X 104 w/cm2 was used to alloy the cam lobe area, while the other area of the cam was treated by laser melting using a focused 12 X 1.5 mm rectangular beam (power density 1.1 X 104 w/cm2) produced by a newly developed binary optics. The microstructure of the laser alloyed region is fine Fe-Cr-Si-B multi-element hypereutectic structure with hardness HRC 63 - 64. The melted layer consists of fine needle-shaped martensite and residual austenite structure with hardness HRC 58 - 61. The strengthened layer is 1.0 - 1.3 mm in thickness with pore-free and crack-free and good surface quality. Under the same condition, the Ring-block (SiN ceramic) wear test proves that the wear of the laser alloyed 45 steel ring is only 29 percent of that of induction quenching 45 steel ring. And a 500 hours test engine experiment demonstrates that the average wear of the laser alloyed cam is only 20 percent of that of induction quenched one.

  20. Fundamental Research in Engineering Education. Identifying and Repairing Student Misconceptions in Thermal and Transport Science: Concept Inventories and Schema Training Studies

    Science.gov (United States)

    Miller, Ronald L.; Streveler, Ruth A.; Yang, Dazhi; Roman, Aidsa I. Santiago

    2011-01-01

    This paper summarizes progress on two related lines of chemical engineering education research: 1) identifying persistent student misconceptions in thermal and transport science (fluid mechanics, heat transfer, and thermodynamics); and, 2) developing a method to help students repair these misconceptions. Progress on developing the Thermal and…

  1. Fundamental Research in Engineering Education. Identifying and Repairing Student Misconceptions in Thermal and Transport Science: Concept Inventories and Schema Training Studies

    Science.gov (United States)

    Miller, Ronald L.; Streveler, Ruth A.; Yang, Dazhi; Roman, Aidsa I. Santiago

    2011-01-01

    This paper summarizes progress on two related lines of chemical engineering education research: 1) identifying persistent student misconceptions in thermal and transport science (fluid mechanics, heat transfer, and thermodynamics); and, 2) developing a method to help students repair these misconceptions. Progress on developing the Thermal and…

  2. Thermal study of the structure of an internal combustion engine and assessment of cooling system efficiency by a numerical tridimensional simulation

    Energy Technology Data Exchange (ETDEWEB)

    Lagasse, J.P.; Rossi, F.N. (Regie Nationale des Usines Renault 92 - Boulogne (FR))

    1989-01-01

    This paper proposes a calculation tool to evaluate the thermal field of the structure of an internal combustion engine. For this purpose a calculation procedure has been devised to take into account the thermal exchanges with the cooling fluid, the gases taking part to the combustion, the exchanges with the environment under the hood, the lubrificating liquid. The particularity of our study is to model with precision the action of the cooling fluid by solving the tridimensional thermo-hydraulic problem. This enables to evaluate quantitatively the efficiency of the cooling system and the influence of some geometrical modifications. We discuss the case of the housing of a car diesel-engine in using simultaneously an industrial thermo-hydraulic finite elements software (developed by C.E.A.) and a combustion specific one-dimensional software.

  3. A home-size solar-powered engine for cooling systems of generation of electricity

    Energy Technology Data Exchange (ETDEWEB)

    Smetana, F.O.; Bladen, P.G.; Dameron, T.B. III

    1979-01-01

    The paper outlines the steps taken in designing and constructing a solar-powered engine at the N.C. State University, to produce sufficient electricity from sunlight to meet the needs of the average N.C. resident, estimated at being approximately 1000 KWH/month. Attention is given to the component selection and assembly, and an examination of the preliminary system operating results is given. Four criteria for the structure are outlined, including that the structure be able to withstand 100 mph winds and that it requires only bolt-together assembly in relatively light-weight sections.

  4. Nanofluids for power engineering: Emergency cooling of overheated heat transfer surfaces

    Science.gov (United States)

    Bondarenko, B. I.; Moraru, V. N.; Sidorenko, S. V.; Komysh, D. V.

    2016-07-01

    The possibility of emergency cooling of an overheated heat transfer surface using nanofluids in the case of a boiling crisis is explored by means of synchronous recording of changes of main heat transfer parameters of boiling water over time. Two nanofluids are tested, which are derived from a mixture of natural aluminosilicates (AlSi-7) and titanium dioxide (NF-8). It is found that the introduction of a small portions of nanofluid into a boiling coolant (distilled water) in a state of film boiling ( t heater > 500°C) can dramatically decrease the heat transfer surface temperature to 130-150°C, which corresponds to a transition to a safe nucleate boiling regime without affecting the specific heat flux. The fact that this regime is kept for a long time at a specific heat load exceeding the critical heat flux for water and t heater = 125-130°C is particularly important. This makes it possible to prevent a potential accident emergency (heater burnout and failure of the heat exchanger) and to ensure the smooth operation of the equipment.

  5. Dark matter merging induced turbulence as an efficient engine for gas cooling

    CERN Document Server

    Prieto, Joaquin; Martí, Jose

    2011-01-01

    We have performed a cosmological numerical simulation of primordial baryonic gas collapsing onto a $3\\times10^7$M$_{\\odot}$ dark matter (DM) halo. We show that the large scale baryonic accretion process and the merger of few $\\sim10^6$ M$_{\\odot}$ DM halos, triggered by the gravitational potential of the biggest halo, is enough to create super sonic ($\\mathcal{M}>10$) shocks and develop a turbulent environment. In this scenario the post shocked regions are able to produced both H$_2$ and HD molecules very efficiently reaching maximum abundances of $n_\\mathrm{H_2}\\sim10^{-2}n_\\mathrm{H}$ and $n_\\mathrm{HD}\\sim \\mathrm{few}\\times10^{-6}n_\\mathrm{H}$, enough to cool the gas below 100K in some regions. The kinetic energy spectrum of the turbulent primordial gas is close to a Burgers spectrum, $\\hat{E}_k\\propto k^{-2}$, and the solenoidal to total kinetic energy ratio is $0.65\\la R_k\\la0.7$ for a wide range of wave numbers; this value is close to $R_k\\approx 2/3$ natural equipartition energy value of a random turb...

  6. Pemanfaatan Perbedaan Temperatur pada Main Engine Cooling System sebagai Energi Alternatif untuk Pembangkit Listrik di Kapal

    Directory of Open Access Journals (Sweden)

    Teguh Julianto

    2017-01-01

    Full Text Available Dari 100 persen bahan bakar yang masuk ke dalam mesin kapal, hanya sekitar 40 persem yang dikonversi menjadi daya. Sedangkan 30 persen panas dilepas menuju sistem pendingin (cooling system dan sisanya menjadi gas buang (exhaust. Energi panas yang terbuang tersebut bisa dimanfaatkan menjadi energi listrik. Perbedaan temperatur antara air panas yang keluar dari mesin kapal dan air laut yang digunakan sebagai pendingin dapat dikonversi menjadi energi listrik dengan menggunakan thermoelectric. Besarnya daya listrik yang dihasilkan tergantung pada besarnya perbedaan temperatur dan jumlah thermoelectric yang dipasang. Tujuan dari penelitian ini adalah untuk menemukan metode yang tepat guna memanfaatkan energi panas yang terbuang pada sistem pendingin mesin. Metode yang digunakan adalah dengan melakukan kajian pustaka serta analisa ekperimen menggunakan prototype. Hasil penelitian berdasarkan keluaran  jacket water mesin Wartsila 6L20 sebesar 91 oC yang harus didinginkan dengan air laut bertemperatur 30oC didapatkan daya sebesar 32,4 Watt dari 12 thermoelectric yang dipasang. Dengan penyerapan energi sebesar 0,4 persen. Dengan begitu, masih banyak potensi energi yang masih bisa diserap untuk diubah menjadi energi listrik. Sehingga, dari penelitian tersebut dapat disimpulkan bahwa panas yang terbuang dari mesin yang dianggap tidak berguna dapat diubah menjadi energi listrik yang ramah lingkungan.

  7. Engineering

    National Research Council Canada - National Science Library

    Includes papers in the following fields: Aerospace Engineering, Agricultural Engineering, Chemical Engineering, Civil Engineering, Electrical Engineering, Environmental Engineering, Industrial Engineering, Materials Engineering, Mechanical...

  8. Preliminary Tests of Blowers of Three Designs Operating in Conjunction with a Wing-Duct Cooling System for Radial Engines, Special Report

    Science.gov (United States)

    Biermann, David; Valentine, E. Floyd

    1939-01-01

    This paper is one of several dealing with methods intended to reduce the drag of present-day radial engine installations and improve the cooling at zero and low air speeds, The present paper describes model wind-tunnel tests of blowers of three designs tested in conjunction with a wing-nacelle combination. The principle of operation involved consists of drawing cooling air into ducts located in the wing root at the point of maximum slipstream velocity, passing the air through the engine baffles from rear to front, and exhausting the air through an annular slot located between the propeller and the engine with the aid of a blower mounted on the spinner. The test apparatus consisted essentially of a stub wing having a 5-foot chord and a 15-foot span, an engine nacelle of 20 inches diameter enclosing a 25-horsepower electric motor, and three blowers mounted on propeller spinners. Two of the blowers utilize centrifugal force while the other uses the lift from airfoils to force the air out radially through the exit slot. Maximum efficiencies of over 70 percent were obtained for the system as a whole. Pressures were measured over the entire flight range which were in excess of those necessary to cool present-day engines, The results indicated that blowers mounted on propeller spinners could be built sufficiently powerful and efficient to warrant their use as the only, or chief, means of forcing air through the cooling system, so that cooling would be independent of the speed of the airplane.

  9. Analysis and Design of a Dish/Stirling System for Solar Electric Generation with a 2.7 kW Air-Cooled Engine

    OpenAIRE

    Beltrán-Chacón R.; Velázquez-Limón N.; Sauceda-Carvajal D.

    2012-01-01

    This paper presents a mathematical modeling, simulation and design of a solar power system of a parabolic dish with an air-cooled Stirling engine of 2.7 kW. The model used for the solar concentrator, the cavity and the Stirling engine were successfully validated against experimental data. Based on a parametric study, the design of the components of the engine is carried out. The study shows that as system capacity increases, the overall efficiency is limited by the power required by the fan, ...

  10. Auto Mechanics. Heavy Equipment. Small Engines.

    Science.gov (United States)

    Finnerty, Kathy

    Developed for use in auto mechanics, Heavy Equipment Repair and Operation (HERO), and small engines programs, these study guides and supplemental worksheets cover operating principles, lubrication, cooling system, ignition circuit and electrical system, and fuel system. The worksheets and guide questions are phrased to emphasize key points…

  11. Repair of segmental bone defect using Totally Vitalized tissue engineered bone graft by a combined perfusion seeding and culture system.

    Directory of Open Access Journals (Sweden)

    Lin Wang

    Full Text Available BACKGROUND: The basic strategy to construct tissue engineered bone graft (TEBG is to combine osteoblastic cells with three dimensional (3D scaffold. Based on this strategy, we proposed the "Totally Vitalized TEBG" (TV-TEBG which was characterized by abundant and homogenously distributed cells with enhanced cell proliferation and differentiation and further investigated its biological performance in repairing segmental bone defect. METHODS: In this study, we constructed the TV-TEBG with the combination of customized flow perfusion seeding/culture system and β-tricalcium phosphate (β-TCP scaffold fabricated by Rapid Prototyping (RP technique. We systemically compared three kinds of TEBG constructed by perfusion seeding and perfusion culture (PSPC method, static seeding and perfusion culture (SSPC method, and static seeding and static culture (SSSC method for their in vitro performance and bone defect healing efficacy with a rabbit model. RESULTS: Our study has demonstrated that TEBG constructed by PSPC method exhibited better biological properties with higher daily D-glucose consumption, increased cell proliferation and differentiation, and better cell distribution, indicating the successful construction of TV-TEBG. After implanted into rabbit radius defects for 12 weeks, PSPC group exerted higher X-ray score close to autograft, much greater mechanical property evidenced by the biomechanical testing and significantly higher new bone formation as shown by histological analysis compared with the other two groups, and eventually obtained favorable healing efficacy of the segmental bone defect that was the closest to autograft transplantation. CONCLUSION: This study demonstrated the feasibility of TV-TEBG construction with combination of perfusion seeding, perfusion culture and RP technique which exerted excellent biological properties. The application of TV-TEBG may become a preferred candidate for segmental bone defect repair in orthopedic and

  12. Applying Best Practices to Military Commercial-Derivative Aircraft Engine Sustainment: Assessment of Using Parts Manufacturer Approval (PMA) Parts and Designated Engineering Representative (DER) Repairs

    Science.gov (United States)

    2016-01-01

    use of alter- nate part and repair sourcing would have required gathering and ana - lyzing data in several steps, shown below. In practice, we were...Parts and Repairs 47 DER repair parts lists from private-sector companies. We then ana - lyzed DLA distribution center data for quantities of NIINs...PMA Parts and DER Repairs Kendall, Frank , Under Secretary of Defense, Acquisition, Technology, and Logistics, “Better Buying Power: Guidance for

  13. Field monitoring and evaluation of a residential gas-engine-driven heat pump: Volume 1, Cooling season

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.D.

    1995-09-01

    The Federal government is the largest single energy consumer in the United States; consumption approaches 1.5 quads/year of energy (1 quad = 10{sup 15} Btu) at a cost valued at nearly $10 billion annually. The US Department of Energy (DOE) Federal Energy Management Program (FEMP) supports efforts to reduce energy use and associated expenses in the Federal sector. One such effort, the New Technology Demonstration Program (NTDP), seeks to evaluate new energy-saving US technologies and secure their more timely adoption by the US government. Pacific Northwest Laboratory (PNL)is one of four DOE national multiprogram laboratories that participate in the NTDP by providing technical expertise and equipment to evaluate new, energy-saving technologies being studied and evaluated under that program. This two-volume report describes a field evaluation that PNL conducted for DOE/FEMP and the US Department of Defense (DoD) Strategic Environmental Research and Development Program (SERDP) to examine the performance of a candidate energy-saving technology -- a gas-engine-driven heat pump. The unit was installed at a single residence at Fort Sam Houston, a US Army base in San Antonio, Texas, and the performance was monitored under the NTDP. Participating in this effort under a Cooperative Research and Development Agreement (CRADA) were York International, the heat pump manufacturer, Gas Research Institute (GRI), the technology developer; City Public Service of San Antonio, the local utility; American Gas Cooling Center (AGCC); Fort Sam Houston; and PNL.

  14. 新型冷却介质在船用柴油机上的应用%Application of Novel Cooling Media in Marine Diesel Engine

    Institute of Scientific and Technical Information of China (English)

    邹得球; 郭江荣; 朱颖颖; 杨国华; 蒋伟芳; 王炳辉; 陈福洲

    2012-01-01

    采用高载热密度、高传热性能的冷却介质是解决船用柴油机大功率化、紧凑化的有效途径.综述了纳米流体冷却介质在柴油机上强化传热的研究进展.针对船用柴油机散热要求,提出了具有高载热密度的相变流体冷却 技术.研制了石蜡乳状液相变流体并分析了其在船用柴油机上应用的相关性能.为了强化相变流体的传热性能,结合纳米流体技术,制备了纳米粒子/石蜡乳状液复合相变流体,并阐述了该流体在船用柴油机上的应用特点.最后探讨了新型冷却介质在柴油机上应用需要解决的关键问题.%Applying cooling media with higher heat storage density and thermal conductivity is an effective way to realize high power and compact structure for marine diesel engines. The research progress in heat transfer enhancement by using nanometer fluids as marine diesel engine cooling media is reviewed. Aiming at the requirement of cooling marine diesel engine, the technology using phase change fluids with higher heat carrying density as marine engine cooling media is presented. The thermal physical properties of paraffin emulsions are analyzed. For enhancing the thermal performance of the phase change fluids, nanometer-aluminum/paraffin emulsions are prepared by means of ' nanometer technology. Their features in marine diesel engine applications are introduced and main problems in application are discussed.

  15. Tissue engineering and the use of stem/progenitor cells for airway epithelium repair

    Directory of Open Access Journals (Sweden)

    GM Roomans

    2010-06-01

    Full Text Available Stem/progenitor cells can be used to repair defects in the airway wall, resulting from e.g., tumors, trauma, tissue reactions following long-time intubations, or diseases that are associated with epithelial damage. Several potential sources of cells for airway epithelium have been identified. These can be divided into two groups. The first group consists of endogenous progenitor cells present in the respiratory tract. This group can be subdivided according to location into (a a ductal cell type in the submucosal glands of the proximal trachea, (b basal cells in the intercartilaginous zones of the lower trachea and bronchi, (c variant Clara cells (Clarav-cells in the bronchioles and (d at the junctions between the bronchioles and the alveolar ducts, and (e alveolar type II cells. This classification of progenitor cell niches is, however, controversial. The second group consists of exogenous stem cells derived from other tissues in the body. This second group can be subdivided into: (a embryonic stem (ES cells, induced pluripotent stem (iPS cells, or amniotic fluid stem cells, (b side-population cells from bone marrow or epithelial stem cells present in bone marrow or circulation and (c fat-derived mesenchymal cells. Airway epithelial cells can be co-cultured in a system that includes a basal lamina equivalent, extracellular factors from mesenchymal fibroblasts, and in an air-liquid interface system. Recently, spheroid-based culture systems have been developed. Several clinical applications have been suggested: cystic fibrosis, acute respiratory distress syndrome, chronic obstructive lung disease, pulmonary fibrosis, pulmonary edema, and pulmonary hypertension. Clinical applications so far are few, but include subglottic stenosis, tracheomalacia, bronchiomalacia, and emphysema.

  16. Cartilage repair: surgical techniques and tissue engineering using polysaccharide- and collagen-based biomaterials.

    Science.gov (United States)

    Galois, L; Freyria, A M; Grossin, L; Hubert, P; Mainard, D; Herbage, D; Stoltz, J F; Netter, P; Dellacherie, E; Payan, E

    2004-01-01

    Lesions of articular cartilage have a large variety of causes among which traumatic damage, osteoarthritis and osteochondritis dissecans are the most frequent. Replacement of articular defects in joints has assumed greater importance in recent years. This interest results in large part because cartilage defects cannot adequately heal themselves. Many techniques have been suggested over the last 30 years, but none allows the regeneration of the damaged cartilage, i.e. its replacement by a strictly identical tissue. In the first generation of techniques, relief of pain was the main concern, which could be provided by techniques in which cartilage was replaced by fibrocartilage. Disappointing results led investigators to focus on more appropriate bioregenerative approaches using transplantation of autologous cells into the lesion. Unfortunately, none of these approaches has provided a perfect final solution to the problem. The latest generation of techniques, currently in the developmental or preclinical stages, involve biomaterials for the repair of chondral or osteochondral lesions. Many of these scaffolds are designed to be seeded with chondrocytes or progenitor cells. Among natural and synthetic polymers, collagen- and polysaccharide-based biomaterials have been extensively used. For both these supports, studies have shown that chondrocytes maintain their phenotype when cultured in three dimensions. In both types of culture, a glycosaminoglycan-rich deposit is formed on the surface and in the inner region of the cultured cartilage, and type II collagen synthesis is also observed. Dynamic conditions can also improve the composition of such three-dimensional constructs. Many improvements are still required, however, in a number of key aspects that so far have received only scant attention. These aspects include: adhesion/integration of the graft with the adjacent native cartilage, cell-seeding with genetically-modified cell populations, biomaterials that can be

  17. In vitro construction of tissue engineered skin for wound repair after escharectomy of third degree scald: An experimental study

    Directory of Open Access Journals (Sweden)

    Zhong-feng MA

    2016-01-01

    Full Text Available Objective  To observe the practicability and effect of tissue engineered skin for repairing the wound after escharectomy of third degree scald (TDSE in rat model. Methods  Epithelial cells and fibroblasts from newborn SD rats were isolated by enzyme digestion method and cultured in vitro, and porcine acellular dermal matrix (PADM without cytotoxicity was prepared by hyperosmotic saline/sodium hydroxide method. The fibroblasts were mixed with bovine type Ⅰ collagen and inoculated on the surface of PADM. Third passage of cultured epidermal cells from newborn SD rats were inoculated on the collagen surface of the dermal matrix to obtain tissue engineered skin, and it was used to prepare epidermal cell sheet. Forty-eight SD rats with TDSE wound were randomly divided into two groups, then tissue engineered skin (experiment group, and epidermal cell sheet (control group graftings were performed to cover the wounds respectively. Finally, gross observation and histological changes were observed in grafted area. The wound healing rate and wound contraction rate were compared between the two groups. Microvessel count (MVC was performed with antiCD34 monoclonal antibody immunohistochemical staining technique, and vascular endothelial cells were labeled. Basal membrane of the skin was identified by immunohistochemical anti-Laminin staining technique. Results  There was no obvious sign of acute rejection of the graft in both groups. The graft survival rate was 75.05%±3.69%, 83.12%±3.13% and 92.03%±3.87% at the 2th, 4th and 6th week respectively in the experimental group. The graft survival rate was 77.63%±3.23%, 83.17%±3.92% and 91.09%±3.35% at the 2th, 4th and 6th week in the control group. There was no significant difference between the two groups (P>0.05, but the contraction rate of the grafts was 9.13%±2.27%, 18.52%±3.40%, 23.92%±3.01% at the 2th, 4th, 6th week, respectively, in the experimental group, and 14.21%±3.05%, 29.12%±3

  18. Performance of cooling capacity adjustment in gas engine-driven heat pump%燃气机热泵容量调节制冷性能试验

    Institute of Scientific and Technical Information of China (English)

    王明涛; 刘焕卫; 张百浩

    2015-01-01

    Gas engine driven heat pump (GEHP), which mainly consists of a gas engine, an evaporator, a condenser and an expansion valve, can make full use of the waste heat from cylinder jacket and exhaust gas and achieve a higher primary energy ratio (PER) than other forms of heating/cooling systems, and therefore has been considered as a preferable choice in the air-conditioning scheme. Compared with the electric-driven heat pump (EHP), the GEHP has two distinguished advantages: 1) the ability to recover the gas engine waste heat from cylinder jacket and exhaust gas; 2) easy modulation of gas engine speed to meet the cooling loads. In the present article, a novel GEHP which could independently provide heating, cooling and hot water for the buildings was presented. The capacity adjustment and stable operation of GEHP could be achieved by controlling engine rotary speed. The goals of engine rotary speed control were to match the rotary speed and cooling/heating capacity, and keep robust to disturbance. In order to control engine rotary speed effectively, the engine rotary speed expert proportion-integration-differentiation (PID) controller was designed according to the engine rotary speed control knowledge base and the controlling rules in this study. Meanwhile, the energy analysis of GEHP was presented as well as the GEHP operating parameters (such as ambient air temperature, evaporator water flow and engine rotary speed). The engine rotary expert PID controller was applied to the engine rotary speed control in a GEHP system experimentally under different conditions (modulation on cooling loads and anti-disturbance), and the cooling performance characteristics of GEHP were investigated experimentally over a wide range of engine rotary speed (1 400-2 200 r/min). The performance of GEHP was characterized by cooling capacity, waste heat amount recovered, coefficient of performance (COP) and PER. The relationships between engine rotary speed and cooling capacity, waste heat

  19. 76 FR 54143 - Airworthiness Directives; Turbomeca Arriel 1B Turboshaft Engines

    Science.gov (United States)

    2011-08-31

    ... turbine damage, and removal of the engine from service before further flight if turbine damage is found... daily checks, remove the engine from service before further flight. Inspection of Repaired 2nd Stage... cooling holes in the rear flange. Alternative Methods of Compliance (AMOCs) (r) The Manager,...

  20. Cooling Tower Engineering in Thermal Power Generation%火力发电冷却塔工程

    Institute of Scientific and Technical Information of China (English)

    张芳

    2014-01-01

    This paper expounds the working principle of thermal power cooling tower and introduces the construction scheme and safety facilities of the cooling tower.%阐述火力发电冷却塔的工作原理。同时,说明冷却塔施工作业方案及安全设施。

  1. Validation of the Algorithms for Base Exchangeable Repair Costs (Engine) and Base Exchangeable Modification Costs (Engine) for the Component Support Cost System (D160B).

    Science.gov (United States)

    2014-09-26

    REPORTING 010 03 NUMBER. ITEM IDENTIFICATION Oil 03 NOMENCLATURE . ITEM 012 03 PRICE. STANDARD INVENTORY 013 03 CODE, WEAPON SYSTEM SUPPORT 014 05 CODE...elements not used in calculation of standard depot repair prices (* sales prices"). ISI affirms the congruence of the definitions of repair prices as

  2. Analysis and Design of a Dish/Stirling System for Solar Electric Generation with a 2.7 kW Air-Cooled Engine

    Directory of Open Access Journals (Sweden)

    Beltrán-Chacón R.

    2012-01-01

    Full Text Available This paper presents a mathematical modeling, simulation and design of a solar power system of a parabolic dish with an air-cooled Stirling engine of 2.7 kW. The model used for the solar concentrator, the cavity and the Stirling engine were successfully validated against experimental data. Based on a parametric study, the design of the components of the engine is carried out. The study shows that as system capacity increases, the overall efficiency is limited by the power required by the fan, since the design of the cooler needs greater amounts of heat removal by increasing the air flow without affecting the internal conditions of the process (mass flow of working gas and internal dimensions of the same. The system was optimized and achieves an overall efficiency of solar to electric energy conversion of 26.7%. This study shows that the use of an air-cooled Stirling engine is potentially attractive for power generation at low capacities.

  3. Research on Repair Technology for Camshaft of Aviation Piston Engine%航空活塞发动机凸轮轴修理技术研究

    Institute of Scientific and Technical Information of China (English)

    冯世榕

    2015-01-01

    According to the repair for camshaft of the aviation piston engine, the influences of grinding camshaft on the profile line, the contact stress, the lubrication characteristics and the wear resistance are analyzed in this paper, and the feasibility of repair is then demonstrated.The key technology of camshaft repair is analyzed, while method of reverse measurement for the profile line and theoretical model of the profile line reconstruction are then presented, thus the theoretical instruction for the re-pair of camshaft is finally provided.%针对航空活塞发动机凸轮轴修理,分析了轮廓磨削对型线、接触应力、润滑特性以及耐磨性的影响,论证了修理的可行性。分析了凸轮轴修理的关键技术,提出了轮廓型线反求的测量方法和型线重构的理论模型,为凸轮轴的修理提供了理论指导。

  4. A very cool cooling system

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    The NA62 Gigatracker is a jewel of technology: its sensor, which delivers the time of the crossing particles with a precision of less than 200 picoseconds (better than similar LHC detectors), has a cooling system that might become the precursor to a completely new detector technique.   The 115 metre long vacuum tank of the NA62 experiment. The NA62 Gigatracker (GTK) is composed of a set of three innovative silicon pixel detectors, whose job is to measure the arrival time and the position of the incoming beam particles. Installed in the heart of the NA62 detector, the silicon sensors are cooled down (to about -20 degrees Celsius) by a microfluidic silicon device. “The cooling system is needed to remove the heat produced by the readout chips the silicon sensor is bonded to,” explains Alessandro Mapelli, microsystems engineer working in the Physics department. “For the NA62 Gigatracker we have designed a cooling plate on top of which both the silicon sensor and the...

  5. Impingement jet cooling in gas turbines

    CERN Document Server

    Amano, R S

    2014-01-01

    Due to the requirement for enhanced cooling technologies on modern gas turbine engines, advanced research and development has had to take place in field of thermal engineering. Impingement jet cooling is one of the most effective in terms of cooling, manufacturability and cost. This is the first to book to focus on impingement cooling alone.

  6. Microtextured Surfaces for Turbine Blade Impingement Cooling

    Science.gov (United States)

    Fryer, Jack

    2014-01-01

    Gas turbine engine technology is constantly challenged to operate at higher combustor outlet temperatures. In a modern gas turbine engine, these temperatures can exceed the blade and disk material limits by 600 F or more, necessitating both internal and film cooling schemes in addition to the use of thermal barrier coatings. Internal convective cooling is inadequate in many blade locations, and both internal and film cooling approaches can lead to significant performance penalties in the engine. Micro Cooling Concepts, Inc., has developed a turbine blade cooling concept that provides enhanced internal impingement cooling effectiveness via the use of microstructured impingement surfaces. These surfaces significantly increase the cooling capability of the impinging flow, as compared to a conventional untextured surface. This approach can be combined with microchannel cooling and external film cooling to tailor the cooling capability per the external heating profile. The cooling system then can be optimized to minimize impact on engine performance.

  7. Nuclear Engineering Computer Modules, Thermal-Hydraulics, TH-3: High Temperature Gas Cooled Reactor Thermal-Hydraulics.

    Science.gov (United States)

    Reihman, Thomas C.

    This learning module is concerned with the temperature field, the heat transfer rates, and the coolant pressure drop in typical high temperature gas-cooled reactor (HTGR) fuel assemblies. As in all of the modules of this series, emphasis is placed on developing the theory and demonstrating its use with a simplified model. The heart of the module…

  8. An evaluation of Admedus' tissue engineering process-treated (ADAPT) bovine pericardium patch (CardioCel) for the repair of cardiac and vascular defects.

    Science.gov (United States)

    Strange, Geoff; Brizard, Christian; Karl, Tom R; Neethling, Leon

    2015-03-01

    Tissue engineers have been seeking the 'Holy Grail' solution to calcification and cytotoxicity of implanted tissue for decades. Tissues with all of the desired qualities for surgical repair of congenital heart disease (CHD) are lacking. An anti-calcification tissue engineering process (ADAPT TEP) has been developed and applied to bovine pericardium (BP) tissue (CardioCel, AdmedusRegen Pty Ltd, Perth, WA, Australia) to eliminate cytotoxicity, improve resistance to acute and chronic inflammation, reduce calcification and facilitate controlled tissue remodeling. Clinical data in pediatric patients, and additional pre-market authorized prescriber data demonstrate that CardioCel performs extremely well in the short term and is safe and effective for a range of congenital heart deformations. These data are supported by animal studies which have shown no more than normal physiologic levels of calcification, with good durability, biocompatibility and controlled healing.

  9. In-situ engineering of cartilage repair: a pre-clinical in-vivo exploration of a novel system.

    Science.gov (United States)

    Seedhom, B B; Luo, Z-J; Goldsmith, A J; Toyoda, T; Lorrison, J C; Guardamagna, L

    2007-07-01

    This investigation explores a new cartilage repair technique that uses a novel method to secure a non-woven multifilamentous scaffold in the defect site after microfracture. The hypothesis is that a scaffold provides a larger surface area for attachment and proliferation of the mesenchymal stem cells that migrate from the bone marrow. Two in-vivo studies were undertaken in an ovine model. The first study, which lasted for 8 weeks, aimed to compare the new technique with microfracture. Chondral defects, 7 mm in diameter, were created in both femoral medial condyles of five ewes. One defect was treated with the new technique while the contralateral knee was treated with microfracture alone. The results revealed that the quantity of repair tissue was significantly greater in the defects treated with the new system. The second study had two time points, 3 and 6 months, and used 13 ewes. In this study, both defects were treated with the new technique but one received additional subchondral drilling in order to stimulate extra tissue growth. The majority of the implants had good tissue induction, filling 50-100 per cent of the defect volume, while the compressive modulus of the repairs was in the range of 40-70 per cent of that for the surrounding cartilage. In addition, hyaline-like cartilage was seen in all the repairs which had the additional drilling of the subchondral bone.

  10. 2D and 3D Modeling Efforts in Fuel Film Cooling of Liquid Rocket Engines (Conference Paper with Briefing Charts)

    Science.gov (United States)

    2017-01-12

    to determine what parameters drive unsteadiness in fuel films, and how these parameters affect wall temperature profiles. Parametric studies performed...temperature profiles. Parametric studies performed in 2D suggest that a Helmholtz resonator exists for simple slot geometries. Frequencies in 3D were...effect on film cooling effectiveness. In general, the heat flux exhibits complex trends and did not scale well with chamber pressure. ∗Aerospace

  11. Allogeneic versus autologous derived cell sources for use in engineered bone-ligament-bone grafts in sheep anterior cruciate ligament repair.

    Science.gov (United States)

    Mahalingam, Vasudevan D; Behbahani-Nejad, Nilofar; Horine, Storm V; Olsen, Tyler J; Smietana, Michael J; Wojtys, Edward M; Wellik, Deneen M; Arruda, Ellen M; Larkin, Lisa M

    2015-03-01

    The use of autografts versus allografts for anterior cruciate ligament (ACL) reconstruction is controversial. The current popular options for ACL reconstruction are patellar tendon or hamstring autografts, yet advances in allograft technologies have made allogeneic grafts a favorable option for repair tissue. Despite this, the mismatched biomechanical properties and risk of osteoarthritis resulting from the current graft technologies have prompted the investigation of new tissue sources for ACL reconstruction. Previous work by our lab has demonstrated that tissue-engineered bone-ligament-bone (BLB) constructs generated from an allogeneic cell source develop structural and functional properties similar to those of native ACL and vascular and neural structures that exceed those of autologous patellar tendon grafts. In this study, we investigated the effectiveness of our tissue-engineered ligament constructs fabricated from autologous versus allogeneic cell sources. Our preliminary results demonstrate that 6 months postimplantation, our tissue-engineered auto- and allogeneic BLB grafts show similar histological and mechanical outcomes indicating that the autologous grafts are a viable option for ACL reconstruction. These data indicate that our tissue-engineered autologous ligament graft could be used in clinical situations where immune rejection and disease transmission may preclude allograft use.

  12. Research on Cooling Effectiveness in Stepped Slot Film Cooling Vane

    Institute of Scientific and Technical Information of China (English)

    LI Yulong; WU Hong; ZHOU Feng; RONG Chengjun

    2016-01-01

    As one of the most important developments in air cooling technology for hot parts of the aero-engine,film cooling technology has been widely used.Film cooling hole structure exists mainly in areas that have high temperature,uneven cooling effectiveness issues when in actual use.The first stage turbine vanes of the aero-engine consume the largest portion of cooling air,thereby the research on reducing the amount of cooling air has the greatest potential.A new stepped slot film cooling vane with a high cooling effectiveness and a high cooling uniformity was researched initially.Through numerical methods,the affecting factors of the cooling effectiveness of a vane with the stepped slot film cooling structure were researched.This paper focuses on the cooling effectiveness and the pressure loss in different blowing ratio conditions,then the most reasonable and scientific structure parameter can be obtained by analyzing the results.The results show that 1.0 mm is the optimum slot width and 10.0 is the most reasonable blowing ratio.Under this condition,the vane achieved the best cooling result and the highest cooling effectiveness,and also retained a low pressure loss.

  13. Performance of a methane-fuel cooled gutter type flame holder for a ramjet engine combustor. Ramu jet engine nenshokiyo metan nenryomaku reikyaku gatta hoenki no tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Tamaru, T.; Shimodaira, K. (National Aerospace Lab., Chofu, Tokyo (Japan))

    1994-03-10

    A flame holder in which the items requested for a combustor were satisfied as much as possible besides reducing the NOx exhaust, was designed and manufactured. Namely a flame holder which satisfied the total pressure loss ratio below 8% (total pressure loss coefficient 2.86) under a drafting condition of the flight mach number M[sub F] 3, certainly performed a flame holding and stable combustion, and had a flame holder temperature level to be able to secure a durability under a condition of M[sub F]=5, was aimed at. This combustor model was named CG 01, and attaching importance to a pressure loss, flame holder temperature, stable combustibility and so forth, and the tests mainly about a fuel cooling performance of the flame holder have been carried out. Generally speaking, a film cooling convective heat transfer heat flux is seen a dependency on an air velocity. In the tests this time, in a high air velocity condition of T(01)=600 K, there is a possibility that an outer diameter side fuel cooling film was broken away. When a supply air temperature was 900 K or 1200 K, and an equivalent ratio was 0.4 - 0.5, a convection heat transfer heat flux was in an order of 20 - 40 kW/m[sup 2]. 7 refs., 12 figs., 1 tab.

  14. Integration of Carbon Fiber Composite Materials into Air-Cooled Reciprocating Piston Engines for UA V Applications

    Science.gov (United States)

    2012-05-04

    Torlon and proved to be capable of surviving under the loads of an engine. The standard Ford Pinto motor made of metal components produced 88...pounds [2] [7]. The gasoline plastic motor clearly has advantages over the standard metal component engine with large weight savings. Holtzberg’s...2]. The 1990s also witnessed work from Volkswagen to develop composite connecting rods. Titanium bearing surfaces and compression plates were used

  15. 小型柴油机的拆卸和装配修理分析研究%Small diesel engine repair disassembly and assembly analysis

    Institute of Scientific and Technical Information of China (English)

    高艳

    2013-01-01

    Building a new socialist countryside, agricultural machinery will be fully extended. Small diesel engines are the main power machinery in rural China,Small diesel engine has a simple structure, easy maintenance and cheap and so in rural economic life plays a significant role. However, because many users of small diesel engine construction, use and maintenance of knowledge mastered enough, use improper operation, maintenance timing is wrong, seriously affecting the efficiency of a small diesel engine into full play. For small diesel engine problems in use, the small diesel engine dis-assembly and assembly and repair of.%建设社会主义新农村,农用机械必将得到全面推广。小型柴油机是我国农村的主要动力机械,小型柴油机具有结构简单、使用维护方便和价格便宜等特点,在农村的经济生活中发挥着很大的作用。但是由于许多使用者对小型柴油机的构造、使用和维修知识掌握不够,使用操作不当、维护保养失时,严重影响着小型柴油机效率的充分发挥。针对小型柴油机在使用中存在的问题,文章对小型柴油机的拆卸和装配修理进行探析。

  16. 汽车发动机冷却系统设计及稳定性分析与研究%Design and Stability Analysis of Automotive Engine Cooling System

    Institute of Scientific and Technical Information of China (English)

    姜成春

    2014-01-01

    Automotive engine cooling system is an integral part of the structure of the car is very important, the paper automobile engine cooling system design and stability of the in-depth research and analysis, specific description of the characteristics and working principle of automotive engine cooling system.%汽车发动机冷却系统是汽车构造中十分重要的组成部分,本文对汽车发动机冷却系统设计及稳定性进行深入的研究分析,具体介绍了汽车发动机冷却系统的特点及工作原理。

  17. Performance and evaluation of gas engine driven rooftop air conditioning equipment at the Willow Grove (PA) Naval Air Station. Interim report, 1992 cooling season

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, P.R.; Conover, D.R.

    1993-05-01

    In a field evaluation conducted for the US Department of Energy (DOE) Office of Federal Energy Management Program (FEMP), the Pacific Northwest Laboratory (PNL) examined the performance of a new US energy-related technology under the FEMP Test Bed Demonstration Program. The technology was a 15-ton natural gas engine driven roof top air conditioning unit. Two such units were installed on a naval retail building to provide space conditioning to the building. Under the Test Bed Demonstration Program, private and public sector interests are focused to support the installation and evaluation of new US technologies in the federal sector. Participating in this effort under a Cooperative Research and Development Agreement (CRADA) with DOE were the American Gas Cooling Center, Philadelphia Electric Company, Thermo King Corporation, and the US Naval Air Station at Willow Grove, Pennsylvania. Equipment operating and service data as well as building interior and exterior conditions were secured for the 1992 cooling season. Based on a computer assessment of the building using standard weather data, a comparison was made with the energy and operating costs associated with the previous space conditioning system. Based on performance during the 1992 cooling season and adjusted to a normal weather year, the technology will save the site $6,000/yr in purchased energy costs. An additional $9,000 in savings due to electricity demand ratchet charge reductions will also be realized. Detailed information on the technology, the installation, and the results of the technology test are provided to illustrate the advantages to the federal sector of using this technology. A history of the CRADA development process is also reported.

  18. The impact of the weather conditions on the cooling performance of the heat pump driven by an internal natural gas combustion engine

    Directory of Open Access Journals (Sweden)

    Janovcová Martina

    2015-01-01

    Full Text Available Market with sources of heat and cold offers unlimited choice of different power these devices, design technology, efficiency and price categories. New progressive technologies are constantly discovering, about which is still little information, which include heat pumps powered by a combustion engine running on natural gas. A few pieces of these installations are in Slovakia, but no studies about their work and effectiveness under real conditions. This article deals with experimental measurements of gas heat pump efficiency in cooling mode. Since the gas heat pump works only in system air – water, air is the primary low – energy source, it is necessary to monitor the impact of the climate conditions for the gas heat pump performance.

  19. Evaluation of finite element formulations for transient conduction forced-convection analysis. [of heat transfer for active cooling of hypersonic airframe and engine structures

    Science.gov (United States)

    Thornton, E. A.; Wieting, A. R.

    1979-01-01

    Conventional versus upwind convective finite elements, and lumped versus consistent formulations for practical conduction/forced convection analysis are evaluated on the basis of numerical studies, with finite element and finite difference lumped-parameter temperatures compared to closed-form analytical solutions for convection problems. Attention is given to two practical combined conduction and forced convection applications, stressing that the finite element method, showing superior accuracy, is competitive with the finite difference lumped-parameter method. Also considered are the computational time savings offered by the zero capacitance nodes procedure and comparative finite element and finite difference lumped-parameter computer times. The present study has reference to the design of actively cooled engine and airframe structures for hypersonic flight.

  20. Planning and realisation of a central cooling system in an engine factory; Planung und Realisierung einer zentralen Rueckkuehlanlage in einem Motorenwerk

    Energy Technology Data Exchange (ETDEWEB)

    Moegle, R. [Daimler Benz AG, Stuttgart (Germany). Werk Untertuerkheim

    1998-09-01

    Planning and realisation of the cooling system for the Bad Cannstadt-based engine factory relied on practical experience and information on economically efficient cooling water preparation and supply, and combining the know-how from practice with modern project management and work organisation methods, the entire project was successfully concluded despite the high demands in terms of time horizons and cost objectives. The system is characterised by high operating safety and economic efficiency. Operating results obtained with a similar system in the Untertuerkheim-based factory were a particularly valuable source of reference used for system planning and design. The close cooperation of planners and system operators proved to be very fruitful. (orig./CB) [Deutsch] Bei der Planung und Realisierung der Rueckkuehlanlage fuer das Motorenwerk Bad Cannstatt wurden die Erkenntnisse ueber die wirtschaftliche Kuehlwassererzeugung konsequent umgesetzt. Im Rahmen der anspruchsvollen Kosten- und Terminvorgaben wurde mit Hilfe moderner Projekt- und Arbeitstechniken das Ziel, eine betriebssichere und wirtschaftliche Anlage zu erstellen voll erreicht. Die wichtigsten Erfahrungen mit Anlagenkomponenten an anderen Rueckkuehlanlagen im Werk Untertuerkheim sind in die Planung eingeflossen. Hier hat sich die intensive Zusammenarbeit zwischen Planung und Betreiberteam positiv ausgewirkt. (orig.)

  1. Electron cooling

    Science.gov (United States)

    Meshkov, I.; Sidorin, A.

    2004-10-01

    The brief review of the most significant and interesting achievements in electron cooling method, which took place during last two years, is presented. The description of the electron cooling facilities-storage rings and traps being in operation or under development-is given. The applications of the electron cooling method are considered. The following modern fields of the method development are discussed: crystalline beam formation, expansion into middle and high energy electron cooling (the Fermilab Recycler Electron Cooler, the BNL cooler-recuperator, cooling with circulating electron beam, the GSI project), electron cooling in traps, antihydrogen generation, electron cooling of positrons (the LEPTA project).

  2. Stochastic Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Blaskiewicz, M.

    2011-01-01

    Stochastic Cooling was invented by Simon van der Meer and was demonstrated at the CERN ISR and ICE (Initial Cooling Experiment). Operational systems were developed at Fermilab and CERN. A complete theory of cooling of unbunched beams was developed, and was applied at CERN and Fermilab. Several new and existing rings employ coasting beam cooling. Bunched beam cooling was demonstrated in ICE and has been observed in several rings designed for coasting beam cooling. High energy bunched beams have proven more difficult. Signal suppression was achieved in the Tevatron, though operational cooling was not pursued at Fermilab. Longitudinal cooling was achieved in the RHIC collider. More recently a vertical cooling system in RHIC cooled both transverse dimensions via betatron coupling.

  3. The design of multi-megawatt actively cooled beam dumps for the Neutral-Beam Engineering Test Facility

    Science.gov (United States)

    Paterson, J. A.; Koehler, G.; Wells, R. P.

    1981-10-01

    To test neutral beam sources up to 170 keV, 65 Amps, with 30 second beam on times, actively cooled beam dumps for both the neutral and ionized particles are required. The dumps should be able to dissipate a wide range of power density profiles by utilizing a standard modular panel design which is incorporated into a moveable support structure. The thermal hydraulic design of the panels permit the dissipation of 2 kW/sq cm anywhere on the panel surface. The water requirements of the dumps are optimized by restricting the flow to panel sections where the heat flux falls short of the design value. The mechanical design of the beam-dump structures is described along with tests performed on two different panel designs. The dissipation capabilities of the panels were tested at the critical regions to verify their use in the beam dump assemblies.

  4. Role of tissue engineered tendon in tendon repair%组织工程化肌腱在肌腱修复过程中的作用

    Institute of Scientific and Technical Information of China (English)

    李荣

    2011-01-01

    OBJECTIVE: To review the research progress of tendon tissue engineering in the process of tendon repair.METHODS: A computer-based search of PubMed database and VIP database from January 1993 to October 2009 was performed for articles regarding the tendon tissue engineering, bio-mechanical analysis of tendon scaffolds, biomaterials'application in tendon tissue engineering and tissue engineering technology in the clinical application of tendon defect repair.English key words are "tendon transplantation, tissue engineering, biological material, cell stent", Chinese key words are "tendon transplantation, tissue engineering, biomaterials, cell scaffold". A total of 132 literatures were screened out.RESULTS: At present, the tendon tissue engineering research has achieved remarkable results, but there are still some problems for clinical practice and mass production. Many issues need to be further studied and solved prior to tissue engineering truly becomes a treatment of tendon defect and fu nctional reconstruction, such as the best source of seed cells, the ideal scaffold material, the best culture conditions and detection methods of implantation in vivo.CONCLUSION: Truly realizing the replacement of human tissues and organs with the in vitro prefabricated living implant, still faces many challenges.%目的:综述肌腱组织工程在肌腱修复过程中的应用进展.方法:应用计算机检索1993-01/2009-10 PubMed数据库及维普数据库有关肌腱组织工程研究进展、肌腱支架材料生物力学分析、生物材料在肌腱组织工程中应用及组织工程技术在修复肌腱缺损临床应用方面的相关文献,英文检索词为"tendon transplantation,tissue engineering,biologicalmaterial,cell stent",中文检索词为"肌腱移植,组织工程,生物材料,细胞支架".检索文献量总计132篇. 结果:目前组织工程化肌腱的研究已经取得了显著的成果,但要真正应用于临床,大批量生产,仍存在一些问题.诸

  5. Additive Manufacturing of IN100 Superalloy Through Scanning Laser Epitaxy for Turbine Engine Hot-Section Component Repair: Process Development, Modeling, Microstructural Characterization, and Process Control

    Science.gov (United States)

    Acharya, Ranadip; Das, Suman

    2015-09-01

    This article describes additive manufacturing (AM) of IN100, a high gamma-prime nickel-based superalloy, through scanning laser epitaxy (SLE), aimed at the creation of thick deposits onto like-chemistry substrates for enabling repair of turbine engine hot-section components. SLE is a metal powder bed-based laser AM technology developed for nickel-base superalloys with equiaxed, directionally solidified, and single-crystal microstructural morphologies. Here, we combine process modeling, statistical design-of-experiments (DoE), and microstructural characterization to demonstrate fully metallurgically bonded, crack-free and dense deposits exceeding 1000 μm of SLE-processed IN100 powder onto IN100 cast substrates produced in a single pass. A combined thermal-fluid flow-solidification model of the SLE process compliments DoE-based process development. A customized quantitative metallography technique analyzes digital cross-sectional micrographs and extracts various microstructural parameters, enabling process model validation and process parameter optimization. Microindentation measurements show an increase in the hardness by 10 pct in the deposit region compared to the cast substrate due to microstructural refinement. The results illustrate one of the very few successes reported for the crack-free deposition of IN100, a notoriously "non-weldable" hot-section alloy, thus establishing the potential of SLE as an AM method suitable for hot-section component repair and for future new-make components in high gamma-prime containing crack-prone nickel-based superalloys.

  6. Grey Repairable System Analysis

    Institute of Scientific and Technical Information of China (English)

    Renkuan Guo; Charles Ernie Love

    2006-01-01

    In this paper, we systematically discuss the basic concepts of grey theory, particularly the grey differential equation and its mathematical foundation, which is essentially unknown in the reliability engineering community. Accordingly,we propose a small-sample based approach to estimate repair improvement effects by partitioning system stopping times into intrinsic functioning times and repair improvement times. An industrial data set is used for illustrative purposes in a stepwise manner.

  7. A Bilayer Engineered Skin Substitute for Wound Repair in an Irradiation-Impeded Healing Model on Rat

    OpenAIRE

    2015-01-01

    Objective: An engineered skin substitute is produced to accelerate wound healing by increasing the mechanical strength of the skin wound via high production of collagen bundles. During the remodeling stage of wound healing, collagen deposition is the most important event. The collagen deposition process may be altered by nutritional deficiency, diabetes mellitus, microbial infection, or radiation exposure, leading to impaired healing. This study describes the fabrication of an engineered bila...

  8. 14 CFR 25.1043 - Cooling tests.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cooling tests. 25.1043 Section 25.1043... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Cooling § 25.1043 Cooling tests. (a) General. Compliance... during the cooling tests must be the minimum grade approved for the engines, and the mixture...

  9. 14 CFR 27.1043 - Cooling tests.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cooling tests. 27.1043 Section 27.1043... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Cooling § 27.1043 Cooling tests. (a) General. For the tests... during the cooling tests must be of the minimum grade approved for the engines, and the mixture...

  10. A comparison of tissue engineering based repair of calvarial defects using adipose stem cells from normal and osteoporotic rats.

    Science.gov (United States)

    Pei, Ming; Li, Jingting; McConda, David B; Wen, Sijin; Clovis, Nina B; Danley, Suzanne S

    2015-09-01

    Repairing large bone defects presents a significant challenge, especially in those people who have a limited regenerative capacity such as in osteoporotic (OP) patients. The aim of this study was to compare adipose stem cells (ASCs) from both normal (NORM) and ovariectomized (OVX) rats in osteogenic potential using both in vitro and in vivo models. After successful establishment of a rat OP model, we found that ASCs from OVX rats exhibited a comparable proliferation capacity to those from NORM rats but had significantly higher adipogenic and relatively lower osteogenic potential. Thirty-two weeks post-implantation with poly(lactic-co-glycolic acid) (PLGA) alone or PLGA seeded with osteogenic-induced ASCs for critical-size calvarial defects, the data from Herovici's collagen staining and micro-computed tomography suggested that the implantation of ASC-PLGA constructs exhibited a higher bone volume density compared to the PLGA alone group, especially in the NORM rat group. Intriguingly, the defects from OVX rats exhibited a higher bone volume density compared to NORM rats, especially for implantation of the PLGA alone group. Our results indicated that ASC based tissue constructs are more beneficial for the repair of calvarial defects in NORM rats while implantation of PLGA scaffold contributed to defect regeneration in OVX rats.

  11. Air cooling : an experimental method of evaluating the cooling effect of air streams on air-cooled cylinders

    Science.gov (United States)

    Alcock, J F

    1927-01-01

    In this report is described an experimental method which the writer has evolved for dealing with air-cooled engines, and some of the data obtained by its means. Methods of temperature measurement and cooling are provided.

  12. Rapid cooled lens cell

    Science.gov (United States)

    Stubbs, David M.; Hsu, Ike C.

    1991-12-01

    This paper describes the optomechanical design, thermal analysis, fabrication, and test evaluation processes followed in developing a rapid cooled, infrared lens cell. Thermal analysis was the key engineering discipline exercised in the design phase. The effect of thermal stress on the lens, induced by rapid cooling of the lens cell, was investigated. Features of this lens cell that minimized the thermal stress will be discussed in a dedicated section. The results of thermal analysis on the selected lens cell design and the selection of the flow channel design in the heat exchanger will be discussed. Throughout the paper engineering drawings, illustrations, analytical results, and photographs of actual hardware are presented.

  13. The science of conventional and water-cooled monopolar lumbar radiofrequency rhizotomy: an electrical engineering point of view.

    Science.gov (United States)

    Ball, Richard D

    2014-01-01

    Radiofrequency ablation (RFA) is a safe and effective pain therapy used to create sensory dysfunction in appropriate nerves via thermal damage. While commonly viewed as a simple process, RF heating is actually quite complex from an electrical engineering standpoint, and it is difficult for the non-electrical engineer to achieve a thorough understanding of the events that occur. RFA is highly influenced by the configuration and properties of the peri-electrode tissues. To rationally discuss the science of RFA requires that examples be procedure-specific, and lumbar RFA is the procedure selected for this review. Adequate heating of the lumbar medial branch has many potential failure points, and the underlying science is discussed with recommendations to reduce the frequency of failure in heating target tissues. Important technical details of the procedure that are not generally appreciated are discussed, and the status quo is challenged on several aspects of accepted technique. The rationale underlying electrode placement and the limitations of RF heating are, for the most part, commonly misunderstood, and there may even need to be significant changes in how lumbar radiofrequency rhizotomy (RFR) is performed. A new paradigm for heating target tissue may be of value. Foremost in developing best practices for this procedure is avoiding pitfalls. Good RF heating and medial branch lesioning are the rewards for understanding how the process functions, attention to detail, and meticulous attention to electrode positioning.

  14. Compressor bleed cooling fluid feed system

    Science.gov (United States)

    Donahoo, Eric E; Ross, Christopher W

    2014-11-25

    A compressor bleed cooling fluid feed system for a turbine engine for directing cooling fluids from a compressor to a turbine airfoil cooling system to supply cooling fluids to one or more airfoils of a rotor assembly is disclosed. The compressor bleed cooling fluid feed system may enable cooling fluids to be exhausted from a compressor exhaust plenum through a downstream compressor bleed collection chamber and into the turbine airfoil cooling system. As such, the suction created in the compressor exhaust plenum mitigates boundary layer growth along the inner surface while providing flow of cooling fluids to the turbine airfoils.

  15. Performance and evaluation of gas-engine-driven split-system cooling equipment at the Willow Grove Naval Air Station

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, P.R.; Schmelzer, J.R.

    1997-01-01

    DOE`s Federal Energy Management Program supports efforts to reduce energy use and associated expenditures within the federal sector; one such effort, the New Technology Demonstration Program (NTDP)(formerly the Test Bed Demonstration program), seeks to evaluate new energy saving US technologies and secure their more timely adoption by the federal government. This report describes the field evaluation conducted to examine the performance of a 15-ton natural-gas-engine- driven, split-system, air-conditioning unit. The unit was installed at a multiple-use building at Willow Grove Naval Air Station, a regular and reserve training facility north of Philadelphia, and its performance was monitored under the NTDP.

  16. Thermical Load Calculation and Capacity of Cooling and Venting Equipment of a Diesel Engine Emissions Study Bench; Calculo de Cargas Termicas y Capacidad de los Equipos de Refrigeracion y Ventilacion de un Banco de Estudio de Emisiones de Motores Diesel

    Energy Technology Data Exchange (ETDEWEB)

    Rojas Garcia, E.; Fonseca Gonzalez, N. A.

    2005-07-01

    The present report tries to develop the calculation of thermical loads and to define the capacity of the equipments of cooling and ventilation that should have the engines test bench that is being ensemble in the installation of the CIEMAT named {sup D}iesel engine emissions study bench (E65-P0). The test bench is formed essentially by a dynamometrical brake and an engine connected at previous one, both of them inside a cabin of isolation acoustic. The thermical loads to be dissipated will be calculated for all the elements that compose the bench and considering his maximum values, to determine the suitable system of cooling air - water of the devices and ventilation in the cabin. (Author) 2 refs.

  17. 超快硬混凝土修复王在抢修工程中的应用%Application of Restoration of Quickly Harden of Concrete in First-aid Repairing Engineering

    Institute of Scientific and Technical Information of China (English)

    刘明杰

    2011-01-01

    In this paper, taking repairing water-proof pavement of bridge, the author introduced construction technology and features of restoration of quickly harden of concrete in first-aid repairing engineering, which provided reference for similar projects.%以桥梁桥面防水铺装层维修为例,介绍了超快硬混凝土修复王的施工工艺及技术特点,对混凝土修复王的主要性能进行了分析.旨在为以后同类工程提供相关参考。

  18. DOD Initiatives to Rapidly Transition Advanced Coating and Surface Finishing Technologies for Military Turbine Engine Manufacture and Repair

    Science.gov (United States)

    2005-03-21

    of PEWG Projects Involving Plating, Coating, and Surface Finishing • Advanced thermal spray coatings (HVOF) • Electrospark deposition • Laser...EWI, GEAE, P&W, Rolls-Royce FUNDING SOURCES RTOC STATUS OC-ALC request for FY06 Funding 3/21/2005 22 Other Technologies • Electrospark Deposition for...Aircraft Engines PEWG MANAGER Chuck Alford, Anteon Corp TECHNOLOGY OPPORTUNITY ADVANTAGES: Kinetic spray technologies deposit thick coatings with a

  19. Tendon repair

    Science.gov (United States)

    Repair of tendon ... Tendon repair can be performed using: Local anesthesia (the immediate area of the surgery is pain-free) ... a cut on the skin over the injured tendon. The damaged or torn ends of the tendon ...

  20. Potentials of manufacture and repair of nickel base turbine components used in aero engines and power plants by laser metal deposition and laser drilling

    Institute of Scientific and Technical Information of China (English)

    I.Kelbassa; K.Walther; L.Trippe; W.Meiners; C.Over

    2007-01-01

    High pressure turbine (HPT) parts like blades and vanes with integrated cooling channels are challenging concerning overhaul and repair.So far damaged parts have to be replaced by the operator.The aim is to design and implement a refurbishment process chain to avoid scrapping of used parts.This process chain implies three different laser applications 1.Direct Laser Forming (DLF),2.Laser Metal Deposition (LMD) and 3.Laser Drilling (LD).The laser processing was extended in the last years towards application near materials like Nickel and Titanium base alloys.Concerning LMD and DLF the achieved results are investigated regarding macro and micro structure,hardness,defects (e.g.cracks,bonding defects,porosity) and contamination with atmospheric elements (e.g.O, N,C and H) are presented for Titanium alloys like Ti-6Al-4V,Ti-6246 and Ti-17 as well as for Nickel base alloys like Inconel 718 and Rene 80.Suitable process parameters are presented with the achieved static (tensile) and dynamic mechanical properties (HCF) and compared to those of heat treated raw materials.One innovative solution (manufacturing case) is to fabricate the small and complex shaped geometrical elements by LMD and/or DLF.By LMD these elements are built-up directly.With DLF the elements are manufactured separately in the DLF machine and connected by a subsequent joining technique with the large parts.With DLF small complex shaped parts like combustor swirlers,HPT blades and vanes with internal cooling channels are manufactured completely.LMD and DLF can be used in combination with subsequent LD.Depending on the application two different drilling techniques by dominant melt ejection-percussion drilling and trepanning-are classified and characterised.The drilling techniques are exemplarily presented for stainless steel and nickel base alloys (diameter 0.2~0.6 mm,aspect ratio<30,inclination up to 60°) using pulsed laser radiation (Nd:YAG,1064 nm,0.5~1 ms).The experimental results of coaxial

  1. Cooled Ceramic Turbine Vane Project

    Data.gov (United States)

    National Aeronautics and Space Administration — N&R Engineering will investigate the feasibility of cooled ceramics, such as ceramic matrix composite (CMC) turbine blade concepts that can decrease specific...

  2. A study of boiling heat transfer as applied to the cooling of ball bearings in the high pressure oxygen turbopump of the space shuttle main engine

    Science.gov (United States)

    Schreiber, Will

    1986-01-01

    Two sets of ball bearings support the main shaft within the High Pressure Oxygen Turbopump (HPOTP) in the Space Shuttle Main Engine (SSME). In operation, these bearings are cooled and lubricated with high pressure liquid oxygen (LOX) flowing axially through the bearing assembly. Currently, modifications in the assembly design are being contemplated in order to enhance the lifetime of the bearings and to allow the HPOTP to operate under larger loads. An understanding of the fluid dynamics and heat transfer characteristics of the flowing LOX is necessary for the implementation of these design changes. The proposed computational model of the LOX fluid dynamics, in addition to dealing with a turbulent flow in a complex geometry, must address the complication associated with boiling and two-phase flow. The feasibility of and possible methods for modeling boiling heat transfer are considered. The theory of boiling as pertains to this particular problem is reviewed. Recommendations are given for experiments which would be necessary to establish validity for correlations needed to model boiling.

  3. Simulation of engine cooling with coupled 1D and 3D flow computation; Simulation der Motorkuehlung mit Hilfe gekoppelter 1D- und 3D-Stroemungsberechnung

    Energy Technology Data Exchange (ETDEWEB)

    Grafenberger, P.; Klinner, P.; Nefischer, P. [BMW Motoren GmbH, Steyr (Austria); Klingebiel, F. [AMSTRAL Engineering fuer Stroemungsmechanik GmbH, Idstein (Germany)

    2000-04-01

    Shorting the development time for new engines and vehicles is leading to the increasing use of computational design and simulation methods in the automotive industry. For several years now, both one-dimensional and three-dimensional flow computation have been used successfully in the development of cooling systems. However, the fact that less hardware is used in the early development stages makes new demands on the quality and quantity of these simulation results. BMW's diesel development division has been able to improve the quality of the results and to reduce the processing time by improving the model quality and by coupling existing 1D and 3D computational fluid dynamic programmes. (orig.) [German] Die Verkuerzung der Entwicklungszeit neuer Motoren und Automobile fuehrt zu einem verstaerkten Einsatz von rechnergestuetzten Konstruktions- und Simulationsmethoden in der Fahrzeugindustrie. Sowohl eindimensionale als auch dreidimensionale Stroemungsberechnungen werden seit Jahren erfolgreich bei der Entwicklung von Kuehlsystemen eingesetzt. Der Entfall von Hardware-Baugruppen in der fruehen Entwicklungsphase stellt jedoch neue Anforderungen an die Qualitaet und Quantitaet dieser Simulationsergebnisse. Durch Verbesserung der Modellqualitaet und durch Kopplung vorhandener 1D- und 3D-Stroemungsberechnungsprogramme konnten in der Dieselmotorenentwicklung von BMW die Qualitaet der Ergebnisse und die Bearbeitungsgeschwindigkeit deutlich gesteigert werden. (orig.)

  4. Fluorescence molecular tomography enables in vivo visualization and quantification of nonunion fracture repair induced by genetically engineered mesenchymal stem cells.

    Science.gov (United States)

    Zilberman, Yoram; Kallai, Ilan; Gafni, Yossi; Pelled, Gadi; Kossodo, Sylvie; Yared, Wael; Gazit, Dan

    2008-04-01

    Fluorescence molecular tomography (FMT) is a novel tomographic near-infrared (NIR) imaging modality that enables 3D quantitative determination of fluorochrome distribution in tissues of live small animals at any depth. This study demonstrates a noninvasive, quantitative method of monitoring engineered bone remodeling via FMT. Murine mesenchymal stem cells overexpressing the osteogenic gene BMP2 (mMSCs-BMP2) were implanted into the thigh muscle and into a radial nonunion bone defect model in C3H/HeN mice. Real-time imaging of bone formation was performed following systemic administration of the fluorescent bisphosphonate imaging agent OsteoSense, an hydroxyapatite-directed bone-imaging probe. The mice underwent imaging on days 7, 14, and 21 postimplantation. New bone formation at the implantation sites was quantified using micro-computed tomography (micro-CT) imaging. A higher fluorescent signal occurred at the site of the mMSC-BMP2 implants than that found in controls. Micro-CT imaging revealed a mass of mature bone formed in the implantation sites on day 21, a finding also confirmed by histology. These findings highlight the effectiveness of FMT as a functional platform for molecular imaging in the field of bone regeneration and tissue engineering.

  5. Maintenance and repair of LMFBR steam generators: specialists` meeting, O-Arai Engineering Center, Japan, 4-8 June 1984. Summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1984-07-01

    The Specialists` Meeting on "Maintenance and Repair of LMFBR Steam Generators" was held in Oarai, Japan, from 4-8 June 1984. The meeting was sponsored by the International Atomic Energy Agency on the recommendation of the IAEA International Working Group on Fast Reactors and was hosted by the Power Reactor and Nuclear Fuel Development Corporation of Japan. The purpose of the meeting was to review and discuss the experience accumulated in various countries on the general design philosophy of LMFBR steam generators from the view point of maintenance and repair, in-service inspection of steam generator tube bundles, identification and inspection of failed tubes and the cleaning and repairing of failed steam generators. The following main topical areas were discussed by participants: national review presentations on maintenance and repair of LMFBR steam generators - design philosophy for maintenance and repair; research and development work on maintenance and repair; and experience on steam generator maintenance and repair.

  6. Sciatic nerve repair with tissue engineered nerve: Olfactory ensheathing cells seeded poly(lactic-co-glygolic acid conduit in an animal model

    Directory of Open Access Journals (Sweden)

    C W Tan

    2013-01-01

    Full Text Available Background and Aim: Synthetic nerve conduits have been sought for repair of nerve defects as the autologous nerve grafts causes donor site morbidity and possess other drawbacks. Many strategies have been investigated to improve nerve regeneration through synthetic nerve guided conduits. Olfactory ensheathing cells (OECs that share both Schwann cell and astrocytic characteristics have been shown to promote axonal regeneration after transplantation. The present study was driven by the hypothesis that tissue-engineered poly(lactic-co-glycolic acid (PLGA seeded with OECs would improve peripheral nerve regeneration in a long sciatic nerve defect. Materials and Methods: Sciatic nerve gap of 15 mm was created in six adult female Sprague-Dawley rats and implanted with PLGA seeded with OECs. The nerve regeneration was assessed electrophysiologically at 2, 4 and 6 weeks following implantation. Histopathological examination, scanning electron microscopic (SEM examination and immunohistochemical analysis were performed at the end of the study. Results: Nerve conduction studies revealed a significant improvement of nerve conduction velocities whereby the mean nerve conduction velocity increases from 4.2 ΁ 0.4 m/s at week 2 to 27.3 ΁ 5.7 m/s at week 6 post-implantation ( P < 0.0001. Histological analysis revealed presence of spindle-shaped cells. Immunohistochemical analysis further demonstrated the expression of S100 protein in both cell nucleus and the cytoplasm in these cells, hence confirming their Schwann-cell-like property. Under SEM, these cells were found to be actively secreting extracellular matrix. Conclusion: Tissue-engineered PLGA conduit seeded with OECs provided a permissive environment to facilitate nerve regeneration in a small animal model.

  7. Repair of Cartilage injuries using in vitro engineered 3D cartilage tissue- Preliminary Results of Our Animal Studies

    Directory of Open Access Journals (Sweden)

    Arumugam S

    2011-01-01

    Full Text Available Introduction: The cartilage injuries demand novel therapeutic approaches as the success rates of the current conventional strategies for the repair of injured articular cartilages are not that encouraging. Earlier we have reported that the Thermoreversible Gelation Polymer (TGP is an ideal scaffold for human chondrocyte expansion in vitro. In this study, we report the preliminary results of the in vitro expansion, characterization and experimental in vivo transplantation of chondrocytes in a rabbit model of cartilage injury Materials & Methods: Nine rabbits were included in this study scheduled for two years, after approval by the ethics committee. In the first animal, Chondrocytes were isolated from the weight bearing area of patellar groove in the left hindlimb and cultured in TGP Scaffold and maintained at 37°C in 5% carbon dioxide incubator for 64 days without growth factors. Then the TGP-Chondrocyte construct was transplanted into an experimental defect created in the knee of the right forelimb of the same rabbit. After a period of 10 weeks, a biopsy was taken from the transplanted region and subjected to morphological analysis, characterization by histopathology (H&E stain and Immunohistochemistry (S-100 staining.Results: The chondrocytes in the 3D TGP culture had round to oval shaped morphology without any de-differentiation which is otherwise observed in Conventional 2D cultures. A macroscopic structure which resembled cartilage was appreciated in the TGP construct in vitro after 64 days which was then transplanted to the rabbit. The H&E and Immunohistochemistry studies confirmed the presence of chondrocytes in the biopsy tissue. Conclusion: Based on the results, we conclude that the TGP significantly supports the in vitro expansion of chondrocytes for a longer period and the 3D culture using TGP preserves the phenotype of the articular chondrocytes. The tissue thus grown when implanted with the TGP has engrafted well without any

  8. Effects of 'Cooled' Cooling Air on Pre-Swirl Nozzle Design

    Science.gov (United States)

    Scricca, J. A.; Moore, K. D.

    2006-01-01

    It is common practice to use Pre-Swirl Nozzles to facilitate getting the turbine blade cooling air onboard the rotating disk with minimum pressure loss and reduced temperature. Higher engine OPR's and expanded aircraft operating envelopes have pushed cooling air temperatures to the limits of current disk materials and are stressing the capability to cool the blade with practical levels of cooling air flow. Providing 'Cooled' Cooling Air is one approach being considered to overcome these limitations. This presentation looks at how the introduction of 'Cooled' Cooling Air impacts the design of the Pre-Swirl Nozzles, specifically in relation to the radial location of the nozzles.

  9. 组织工程修复肩袖损伤促进腱骨愈合的研究进展%Progress in tissue-engineering for tendon-to-bone healing after rotator cuff repair

    Institute of Scientific and Technical Information of China (English)

    赵晨; 王蕾

    2015-01-01

    Rotator cuff injury, considered as a resource of pain, disability and dyssomnia to serious decline in the quality of life, is a common disorder of the shoulder joint. Basic principles of rotator cuff repair aim at achieving high initial ifxation strength, maintaining mechanical stability and restoring the anatomic healing of the cuff tendon. After the routine surgical procedure for rotator cuff repair, the biology and histology of the normal enthesis are not restored. Tendon-to-bone healing occurs with a ifbrovascular scar tissue interface that is mechanically inferior to the native insertion site, which may lead to high re-rupture rate. For these reasons, new approaches are required to improve structural healing. Tissue engineering strategies have been suggested to improve the biological environment around the bone-tendon interface and to promote regeneration of the native insertion site. Although experimental applications of growth factors and scaffolds on animal models demonstrate promising results, techniques which can be used in human rotator cuff repair are still very limited. Tissue engineering to improve tendon-to-bone healing has bright future and requires more research before its clinical applications. This review will outline therapies of growth factors, scaffolds and stem cells in tendon healing and rotator cuff repair.

  10. Application potential of bone marrow mesenchymal stem cell (BMSCs) based tissue-engineering for spinal cord defect repair in rat fetuses with spina bifida aperta.

    Science.gov (United States)

    Li, Xiaoshuai; Yuan, Zhengwei; Wei, Xiaowei; Li, Hui; Zhao, Guifeng; Miao, Jiaoning; Wu, Di; Liu, Bo; Cao, Songying; An, Dong; Ma, Wei; Zhang, Henan; Wang, Weilin; Wang, Qiushi; Gu, Hui

    2016-04-01

    Spina bifida aperta are complex congenital malformations resulting from failure of fusion in the spinal neural tube during embryogenesis. Despite surgical repair of the defect, most patients who survive with spina bifida aperta have a multiple system handicap due to neuron deficiency of the defective spinal cord. Tissue engineering has emerged as a novel treatment for replacement of lost tissue. This study evaluated the prenatal surgical approach of transplanting a chitosan-gelatin scaffold seeded with bone marrow mesenchymal stem cells (BMSCs) in the healing the defective spinal cord of rat fetuses with retinoic acid induced spina bifida aperta. Scaffold characterisation revealed the porous structure, organic and amorphous content. This biomaterial promoted the adhesion, spreading and in vitro viability of the BMSCs. After transplantation of the scaffold combined with BMSCs, the defective region of spinal cord in rat fetuses with spina bifida aperta at E20 decreased obviously under stereomicroscopy, and the skin defect almost closed in many fetuses. The transplanted BMSCs in chitosan-gelatin scaffold survived, grew and expressed markers of neural stem cells and neurons in the defective spinal cord. In addition, the biomaterial presented high biocompatibility and slow biodegradation in vivo. In conclusion, prenatal transplantation of the scaffold combined with BMSCs could treat spinal cord defect in fetuses with spina bifida aperta by the regeneration of neurons and repairmen of defective region.

  11. MHD-, ships-, jet engine unit consisting of electrochemical cells producing hydrogen, magneto-caloric hydrogen liquefier, liquid hydrogen-cooled high temperature superconductor-, MHD-, jet engine, liquid hydrogen internal combustion engine as high temperature-, superconductor-, generator-drive. High temperature superconductor coil and permanent magnet superconductor hollow cylinder as battery. MHD-Schiffs-Strahltriebwerks-Aggregat bestehend aus Wasserstoff-produzierenden elektrochemischen Solarzellen, magnetokalorischem Wasserstoffverfluessiger, Fluessigwasserstoff gekuehltem Hochtemperatur-Supraleiter-MHD-Strahltriebwerk, Fluessigwasserstoff-Verbrennungsmotor als Hochtemperatur-Supraleiter-Generator-Antrieb, Hochtemperatur-Supraleiter-Spule und permanentmagnetischem Supraleiter-Hohlzylinder als Akku

    Energy Technology Data Exchange (ETDEWEB)

    Berling, E.

    1991-05-02

    MHD-, ships-, jet engine-unit consisting of electrochemical cells producing hydrogen, magneto-caloric hydrogen liquifier, liquid hydrogen-cooled high temperature superconductor-, MHD-, jet engine, liquid hydrogen internal combustion engine as high temperature-, superconductor-, generator-drive. High temperature superconductor coil and permanent magnet superconductor hollow cylinder as battery. Ships water jet engines with magneto hydrodynamic (MHD) low temperature superconductor drive are known. The invention of the ceramic high temperature superconductor MHD drive, which is cooled with liquid hydrogen. The hydrogen is obtained electro-chemically directly from seawater, and is liquified magneto-calorically. The high temperature superconductor elements of the engine, liquifier, generator, storage coil, permanent magnet hollow cylinder store are coupled by a common liquid hydrogen cooling circuit. The internal combustion engine driving the generator is fuelled by the same liquid hydrogen by which the high temperature superconductor elements are cooled.

  12. 骨缺损修复生物工程研究进展%Research progress of biological engineering on bone defect repairing

    Institute of Scientific and Technical Information of China (English)

    郭宜姣; 李文华

    2014-01-01

    临床上对于骨缺损的治疗从截肢,自体骨、异体骨移植,到目前的生物活性材料、骨组织工程、基因工程治疗,依然没有能够彻底进行骨缺损修复的方法,这也一直是医学界关注和研究的热点。究其原因一方面是因为各种方法的技术水平还不完善如手术时间和方法掌握,生物活性材料的制作等,另一方面是因为骨缺损的局部反应较复杂如骨髓损伤较重,血运较差,断端存在的硬化反应等以及传统治疗后的并发症较多如免疫排斥较重,成骨作用不良,骨折不愈合,神经损伤长期引发的疼痛等,这些原因都在不同程度的制约骨缺损研究的前进。只有从骨的修复与生长机制出发,联合应用多种方法,相互补其不足,从中找到突破点,才能完善骨缺损修复,缩短治疗时间,提高病人的生活质量。本文简要描述自体和异体骨移植在治疗骨缺损时的优缺点,着重叙述骨组织工程与基因工程近年来的研究热点,包括生物材料的更新换代、目的细胞的种类增加、生长因子与基因载体的研究进展等,这其中探讨了生物修复骨缺损工程中两种方法各自的利弊,阐述两种工程联合应用的优缺互补,最后提出骨缺损治疗研究方向上的新思路与新问题。%The treatment for bone defect in clinic varies from amputation, autogenous bone graft, and allograft.Up to now, the biological activity material, bone tissue engineering, and gene engineering treatment are still not able to completely repair the bone defect.It has been a hot spot in medical field.One of the reasons is the limitation of technology, such as the mastery of operation time and method and the manufacture of bioactive materials.On the other hand, the local reactions of bone defect are complicated, such as serous bone marrow damage, poor blood supply, the hardening reaction in the cutting ends, and more

  13. Regeneratively Cooled Porous Media Jacket

    Science.gov (United States)

    Mungas, Greg (Inventor); Fisher, David J. (Inventor); London, Adam Pollok (Inventor); Fryer, Jack Merrill (Inventor)

    2013-01-01

    The fluid and heat transfer theory for regenerative cooling of a rocket combustion chamber with a porous media coolant jacket is presented. This model is used to design a regeneratively cooled rocket or other high temperature engine cooling jacket. Cooling jackets comprising impermeable inner and outer walls, and porous media channels are disclosed. Also disclosed are porous media coolant jackets with additional structures designed to transfer heat directly from the inner wall to the outer wall, and structures designed to direct movement of the coolant fluid from the inner wall to the outer wall. Methods of making such jackets are also disclosed.

  14. Investigations of Air-cooled Turbine Rotors for Turbojet Engines II : Mechanical Design, Stress Analysis, and Burst Test of Modified J33 Split-disk Rotor / Richard H. Kemp and Merland L. Moseson

    Science.gov (United States)

    Kemp, Richard H; Moseson, Merland L

    1952-01-01

    A full-scale J33 air-cooled split turbine rotor was designed and spin-pit tested to destruction. Stress analysis and spin-pit results indicated that the rotor in a J33 turbojet engine, however, showed that the rear disk of the rotor operated at temperatures substantially higher than the forward disk. An extension of the stress analysis to include the temperature difference between the two disks indicated that engine modifications are required to permit operation of the two disks at more nearly the same temperature level.

  15. Effect of Chitosan on Tissue Repair in Bone Tissue Engineering%壳聚糖对骨组织工程中组织修复的影响

    Institute of Scientific and Technical Information of China (English)

    焦延鹏; 李立华; 罗丙红; 周长忍

    2012-01-01

    Materials implanted in the body would inevitably lead to host response, promoting or inhibiting tissue heal- ing. The degradation products of biodegradable materials in the body will change with time, resulting in different host re- sponses and further affecting tissue healing. Therefore, the mechanism of promoting or inhibiting tissue healing becomes the theoretical basis for the design and preparation of novel biomedical polymer materials. Chitosan is one of the ideal med- ical polymer materials, but we still do not know the effect mechanism of chitosan degradation process on tissue repair in vi- vo. So it will not be able to design chitosan-based materials with excellent performance. This review does not lay out the progress of the chitosan-based biomaterials applied in bone tissue engineering, but focuses on the complexity of chitosan applications for bone tissue engineering, furthermore investigates the problems needed to be solved for chitosan used in bone tissue engineering.%材料植入体内必然引起宿主体的应答,促进或抑制组织愈合。由于降解材料在体内的降解产物会随时间而变,产生的宿主体应答就会不同,进而会影响组织的愈合。而促进或抑制组织愈合的机制就成为新型医用高分子材料设计和制备的理论基础。壳聚糖是理想的骨组织修复材料之一,但至今还不清楚壳聚糖体内不同降解过程对组织修复的影响机制,也就无法设计出性能优良的壳聚糖基新材料。文章没有罗列壳聚糖基生物材料在骨组织工程中应用所取得的进展,而是重点阐述了壳聚糖在骨组织工程中应用的复杂性和对组织修复的影响,探讨了壳聚糖进一步用于骨组织工程所需要解决的问题。

  16. Danish Cool

    DEFF Research Database (Denmark)

    Toft, Anne Elisabeth

    2016-01-01

    Danish Cool. Keld Helmer-Petersen, Photography and the Photobook Handout exhibition text in English and Chinese by Anne Elisabeth Toft, Curator The exhibition Danish Cool. Keld Helmer-Petersen, Photography and the Photobook presents the ground-breaking work of late Danish photographer Keld Helmer...

  17. Bladder exstrophy repair

    Science.gov (United States)

    Bladder birth defect repair; Everted bladder repair; Exposed bladder repair; Repair of bladder exstrophy ... Bladder exstrophy repair involves two surgeries. The first surgery is to repair the bladder and the second one is to attach ...

  18. Alternative Room Cooling System

    Directory of Open Access Journals (Sweden)

    Md. Fazle Rabbi

    2015-06-01

    Full Text Available The rapidly growing population results in an increasing demand for much more residential and commercial buildings, which leads to vertical growth of the buildings and needs proper ventilation of those buildings. Natural air ventilation system is not sufficient for conventional building structures. Hence fans and air-conditioners are must to meet the requirement of proper ventilation as well as space conditioning. Globally building sector consumes largest energy in heating, cooling, ventilation and space conditioning. This load can be minimized by the application of solar chimney and modification in building structure for heating, cooling, ventilation and space conditioning. Passive solar cooling is a subject of interest to provide cooling by using the sun, a powerful energy source. This is done for ensuring human comfort in hot climates. ASHRAE (American Society of Heating, Refrigerating and Air Conditioning Engineers defines Comfort as ‘that state of mind which expresses satisfaction with the thermal environment.’ The present paper describes the development of a solar passive cooling system, which can provide thermal cooling throughout the summer season in hot and humid climates. The constructed passive system works on natural convection mode of air. Such system reduces the inside temperature of up to 5°C from the atmospheric temperature. Temperature can further be reduced by the judicious use of night ventilation.

  19. Rapid maxillary expansion in alveolar cleft repaired with a tissue-engineered bone in a canine model.

    Science.gov (United States)

    Huang, Jialiang; Tian, Bo; Chu, Fengting; Yang, Chenjie; Zhao, Jun; Jiang, Xinquan; Qian, Yufen

    2015-08-01

    This study aims to investigate the effects of orthodontic expansion on graft area of a tissue-engineered bone (TEB) BMSCs/β-TCP, and to find an alternative strategy for the therapy of alveolar cleft. A unilateral alveolar cleft canine model was established and then treated with BMSCs/β-TCP under rapid maxillary expansion (RME). Sequential fluorescent labeling, radiography and helical computed tomography were used to evaluate new bone formation and mineralization in the graft area. Hematoxylin-eosin staining and Van Gieson׳s picro fuchsin staining were performed for histological and histomorphometric observation. ALP activity, mineralization and the expression of osteogenic differentiation related genes of BMSCs that grew on the β-TCP scaffold were promoted by their cultivation in osteogenic medium. Based on fact, TEB was constructed. After 8 weeks of treatment with BMSCs/β-TCP followed by RME, new bone formation and mineralization of the dogs were markedly accelerated, and bone resorption was significantly reduced, compared with the untreated dogs, or those only treated with autogenous iliac bone. The treatment with both TEB and RME evidently made the bone trabecula more abundant and the area of bone formation larger. What is more, there were no significant differences between BMSCs/β-TCP group and the group treated with autogenous bone and RME. This study further revealed that TEB was not only a feasible clinical approach for patients with alveolar cleft, but also a potential substituent of autogenous bone, and its combination with RME might be an alternative strategy for the therapy of alveolar cleft.

  20. 汽车发动机冷却系统的腐蚀与防护%CORROSION AND PROTECTION OF COOLING SYSTEM OF AUTOMOTIVE ENGINE

    Institute of Scientific and Technical Information of China (English)

    刘丽明; 王晓波; 王萍; 张焕仁

    2001-01-01

    参照日本防冻液的金属腐蚀试验方法JIS-K-2234,对各种不同的复合型缓蚀剂配制的防冻液进行了金属腐蚀试验测试,并对测试结果进行了分析讨论,最后确定了对铸铁、钢、铜、铸铝、锡都具有较好缓蚀作用的复合型缓蚀剂的科学配制方法,利用美国ASTM方法对防冻液进行了性能测试。配制的防冻液可以有效地延长汽车发动机冷却系统的使用寿命,使汽车达到高性能化。%By reference to metal corrosion test methods JIS -K-2234 some,anti-freeze fluids which were made up of various compounded-typ e inhibitor were tested for metal corrosion.The results were discussed,the scientific methods of making up compounded-type inhibitor which can play better role of inhibitor for ordinary iron,steel,copper,ordinary aluminium、tin wer e determined at last.By the methods of ASTM the performance of anti-freeze flui d has been tested.The anti-freeze fluids which was so formed can prolong effe cti vly service life of cooling system of automotive engine,and can make automotive having high property.

  1. 40 CFR 89.327 - Charge cooling.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Charge cooling. 89.327 Section 89.327....327 Charge cooling. For engines with an air-to-air intercooler (or any other low temperature charge air cooling device) between the turbocharger compressor and the intake manifold, follow SAE...

  2. Tissue-engineered bone repairs sheep alveolar bone defects%组织工程化骨修复羊牙槽骨缺损***

    Institute of Scientific and Technical Information of China (English)

    张琴; 杨川博; 何惠宇; 崔杰; 杨楠; 马文渊

    2013-01-01

    BACKGROUND:Fol owing physicochemical treatment and high-temperature calcinations, heterogeneous biological bone becomes a ceramic-like heterologous bone forming a similar structure to the human bone that is a natural network pore structure, which is conducive to seed cel adhesion and proliferation. OBJECTIVE:To observe the feasibility of constructing tissue-engineered bone through combination of sintered bone and bone marrow mesenchymal stem cel s to repair alveolar defects. METHODS:Sheep bone marrow mesenchymal stem cel s as seed cel s were combined with the high temperature sintered bone as scaffold materials to construct tissue-engineered bone. Under general anesthesia, sheep bilateral mandibular first premolars were removed in batches, the alveolar ridge space between the distal root and mesial root of the second premolar to form a bone defect area of 5 mm×5 mm×5 mm. Twelve experimental sheep were equal y randomized into tissue-engineered bone group and sintered bone group, which were implanted with tissue-engineered bone and sintered bone, respectively, at the left surgical area of the mandible. The right surgical area was considered as blank control group. RESULTS AND CONCLUSION:After high-temperature calcinations, the sintered bone was chalk in color, exhibiting a porous structure as the natural cancel ous bone. The porosity was (66.10±1.32)%, and the pore size was between 137.44μm and 538.72μm. After 24 hours of bone marrow mesenchymal stem cel s inoculated to the sintered bone, a large number of cel s are visible adherent to the scaffold;up to day 7, extracel ular matrix was secreted and there was no clear boundary between the cel s and the matrix. X-ray films showed that the tissue-engineered bone and pure sintered bone implants were embedded in the surgical area, and there was a low-density shadow at the edge of the sintered bone. Hematoxylin-eosin staining showed bone trabecular formation at the experimental side, but no obvious bone formation at

  3. 40 CFR 92.1004 - Maintenance and repair.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Maintenance and repair. 92.1004... Owners and Operators of Locomotives and Locomotive Engines § 92.1004 Maintenance and repair. (a) Unless..., all maintenance and repair of locomotives and locomotive engines subject to the provisions of...

  4. A review of engine cooling water pump%汽车发动机冷却水泵的研究进展

    Institute of Scientific and Technical Information of China (English)

    李维强; 李伟; 施卫东; 季磊磊; 赵晓凡

    2016-01-01

    Cooling system has an important influence on automobile engine performance,and engine cooling water pump (ECWP)in the system has been a research focus at home and abroad.Structural characteristics and hydraulic performances of centrifugal ECWP are analyzed,and the key factors affec-ting the development of ECWP are also summarized.Cavitation in the ECWP occurs easier under the high working temperature,the limited seriously space structure and the changed severely rotating speed, which seriously affects the cooling system's stability and reliability and brings into a series of problems such as bearing damage,seal failure,shaft fatigue fracture and noise.In this study,achievements on hydraulic,cavitation performances and reliability of ECWP are reviewed,and the development tendency and research focuses in the future are put forward.Firstly,a connection between internal flow feature and hydrodynamic performance needs to be established based on the particle image velocimetry (PIV) technology.Secondly,cavitation mechanism of ECWP with thermodynamic effect needs to be understood and the disadvantage of pressure pulsation caused by cavitation needs to be clarified to improve hydrody-namic performance and reliability.At last,standardization,modularization and serialization of ECWP components should be paid attention,and a development model called "Internet plus Automobile Stan-dard Parts"should be constructed to make ECWP intelligent,controllable and efficient.%冷却系统对汽车发动机性能具有重要的影响,发动机冷却水泵已成为国内外的研究热点。分析了离心式发动机冷却水泵的结构特点与能量特性,总结了制约汽车发动机冷却水泵发展的关键影响因素。由于发动机冷却水泵的空间结构受限、工作环境温度高、转速变化大,工作过程极易发生汽蚀破坏,严重影响发动机冷却水泵及冷却系统的可靠及稳定运行,易出现轴承损坏、水封失效、振动噪声

  5. Multi-pass cooling for turbine airfoils

    Science.gov (United States)

    Liang, George

    2011-06-28

    An airfoil for a turbine vane of a gas turbine engine. The airfoil includes an outer wall having pressure and suction sides, and a radially extending cooling cavity located between the pressure and suction sides. A plurality of partitions extend radially through the cooling cavity to define a plurality of interconnected cooling channels located at successive chordal locations through the cooling cavity. The cooling channels define a serpentine flow path extending in the chordal direction. Further, the cooling channels include a plurality of interconnected chambers and the chambers define a serpentine path extending in the radial direction within the serpentine path extending in the chordal direction.

  6. Lunar nuclear power plant design for thermal-hydraulic cooling in nano-scale environment: Nuclear engineering-based interdisciplinary nanotechnology

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Tae Ho [Systemix Global Co. Ltd., Seoul (Korea, Republic of)

    2015-05-15

    The environment of the Moon is nearly vacant, which has very low density of several kinds of gases. It has the molecular level contents of the lunar atmosphere in Table 1, which is recognized that radiation heat transfer is a major cooling method. The coolant of the nuclear power plant (NPP) in the lunar base is the Moon surface soil , which is known as the regolith. The regolith is the layer of loose and heterogeneous material covering the solid rock. For finding the optimized length of the radiator of the coolant in the lunar NPP, the produced power and Moon environmental temperature are needed. This makes the particular heat transfer characteristics in heat transfer in the Moon surface. The radiation is the only heat transfer way due to very weak atmosphere. It is very cold in the night time and very hot in the daytime on the surface of the ground. There are comparisons between lunar high land soil and Earth averages in Table 2. In the historical consideration, Konstantin Tsiolkovsky made a suggestion for the colony on the Moon.. There are a number of ideas for the conceptual design which have been proposed by several scientists. In 1954, Arthur C. Clarke mentioned a lunar base of inflatable modules covered in lunar dust for insulation. John S. Rinehart suggested the structure of the stationary ocean of dust, because there could be a mile-deep dust ocean on the Moon, which gives a safer design. In 1959, the project horizon was launched regarding the U.S. Army's plan to establish a fort on the Moon by 1967. H. H. Koelle, a German rocket engineer of the Army Ballistic Missile Agency, leaded the project (ABMA). There was the first landing in 1965 and 245 tons of cargos were transported to the outpost by 1966. The coolant material of regolith in the Moon is optimized for the NPP. By the simulation, there are some results. The temperature is calculated as the 9 nodals by radiation heat transfer from the potassium coolant to the regolith flow. The high efficiency

  7. Ventilative Cooling

    DEFF Research Database (Denmark)

    Heiselberg, Per Kvols; Kolokotroni, Maria

    This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state-of-the-art of ventil......This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state...

  8. Hypospadias repair

    Science.gov (United States)

    ... the problem. If the repair is not done, problems may occur later on such as: Difficulty controlling and directing urine stream A curve in the penis during erection Decreased fertility Embarrassment about appearance of penis Surgery ...

  9. Cooling towers principles and practice

    CERN Document Server

    Hill, G B; Osborn, Peter D

    1990-01-01

    Cooling Towers: Principles and Practice, Third Edition, aims to provide the reader with a better understanding of the theory and practice, so that installations are correctly designed and operated. As with all branches of engineering, new technology calls for a level of technical knowledge which becomes progressively higher; this new edition seeks to ensure that the principles and practice of cooling towers are set against a background of up-to-date technology. The book is organized into three sections. Section A on cooling tower practice covers topics such as the design and operation of c

  10. 不解体清洗大型车辆水冷发动机技术研究%On the Technology of Cleaning Water Cooling Engine for Large Vehicles without Disassembly

    Institute of Scientific and Technical Information of China (English)

    张昕; 张昊

    2014-01-01

    通过分析水冷发动机水道结垢的原因及危害,研制出一种新型、使用简便的清洗除垢剂和导电聚苯胺水箱防腐剂。%Through analyzing the causes and damage of the fouling in water channel of water cooling engine, this paper develops a new kind of compound cleaning and descaling agent and conducting polyaniline corrosion agent of the water tank.

  11. Cool snacks

    DEFF Research Database (Denmark)

    Grunert, Klaus G; Brock, Steen; Brunsø, Karen

    2016-01-01

    such a product requires an interdisciplinary effort where researchers with backgrounds in psychology, anthropology, media science, philosophy, sensory science and food science join forces. We present the COOL SNACKS project, where such a blend of competences was used first to obtain thorough insight into young...

  12. Stochastic cooling

    Energy Technology Data Exchange (ETDEWEB)

    Bisognano, J.; Leemann, C.

    1982-03-01

    Stochastic cooling is the damping of betatron oscillations and momentum spread of a particle beam by a feedback system. In its simplest form, a pickup electrode detects the transverse positions or momenta of particles in a storage ring, and the signal produced is amplified and applied downstream to a kicker. The time delay of the cable and electronics is designed to match the transit time of particles along the arc of the storage ring between the pickup and kicker so that an individual particle receives the amplified version of the signal it produced at the pick-up. If there were only a single particle in the ring, it is obvious that betatron oscillations and momentum offset could be damped. However, in addition to its own signal, a particle receives signals from other beam particles. In the limit of an infinite number of particles, no damping could be achieved; we have Liouville's theorem with constant density of the phase space fluid. For a finite, albeit large number of particles, there remains a residue of the single particle damping which is of practical use in accumulating low phase space density beams of particles such as antiprotons. It was the realization of this fact that led to the invention of stochastic cooling by S. van der Meer in 1968. Since its conception, stochastic cooling has been the subject of much theoretical and experimental work. The earliest experiments were performed at the ISR in 1974, with the subsequent ICE studies firmly establishing the stochastic cooling technique. This work directly led to the design and construction of the Antiproton Accumulator at CERN and the beginnings of p anti p colliding beam physics at the SPS. Experiments in stochastic cooling have been performed at Fermilab in collaboration with LBL, and a design is currently under development for a anti p accumulator for the Tevatron.

  13. Turbine airfoil with ambient cooling system

    Science.gov (United States)

    Campbell, Jr, Christian X.; Marra, John J.; Marsh, Jan H.

    2016-06-07

    A turbine airfoil usable in a turbine engine and having at least one ambient air cooling system is disclosed. At least a portion of the cooling system may include one or more cooling channels configured to receive ambient air at about atmospheric pressure. The ambient air cooling system may have a tip static pressure to ambient pressure ratio of at least 0.5, and in at least one embodiment, may include a tip static pressure to ambient pressure ratio of between about 0.5 and about 3.0. The cooling system may also be configured such that an under root slot chamber in the root is large to minimize supply air velocity. One or more cooling channels of the ambient air cooling system may terminate at an outlet at the tip such that the outlet is aligned with inner surfaces forming the at least one cooling channel in the airfoil to facilitate high mass flow.

  14. Cooling arrangement for a gas turbine component

    Science.gov (United States)

    Lee, Ching-Pang; Heneveld, Benjamin E

    2015-02-10

    A cooling arrangement (82) for a gas turbine engine component, the cooling arrangement (82) having a plurality of rows (92, 94, 96) of airfoils (98), wherein adjacent airfoils (98) within a row (92, 94, 96) define segments (110, 130, 140) of cooling channels (90), and wherein outlets (114, 134) of the segments (110, 130) in one row (92, 94) align aerodynamically with inlets (132, 142) of segments (130, 140) in an adjacent row (94, 96) to define continuous cooling channels (90) with non continuous walls (116, 120), each cooling channel (90) comprising a serpentine shape.

  15. Pressure drop, heat transfer, critical heat flux, and flow stability of two-phase flow boiling of water and ethylene glycol/water mixtures - final report for project "Efficent cooling in engines with nucleate boiling."

    Energy Technology Data Exchange (ETDEWEB)

    Yu, W.; France, D. M.; Routbort, J. L. (Energy Systems)

    2011-01-19

    Because of its order-of-magnitude higher heat transfer rates, there is interest in using controllable two-phase nucleate boiling instead of conventional single-phase forced convection in vehicular cooling systems to remove ever increasing heat loads and to eliminate potential hot spots in engines. However, the fundamental understanding of flow boiling mechanisms of a 50/50 ethylene glycol/water mixture under engineering application conditions is still limited. In addition, it is impractical to precisely maintain the volume concentration ratio of the ethylene glycol/water mixture coolant at 50/50. Therefore, any investigation into engine coolant characteristics should include a range of volume concentration ratios around the nominal 50/50 mark. In this study, the forced convective boiling heat transfer of distilled water and ethylene glycol/water mixtures with volume concentration ratios of 40/60, 50/50, and 60/40 in a 2.98-mm-inner-diameter circular tube has been investigated in both the horizontal flow and the vertical flow. The two-phase pressure drop, the forced convective boiling heat transfer coefficient, and the critical heat flux of the test fluids were determined experimentally over a range of the mass flux, the vapor mass quality, and the inlet subcooling through a new boiling data reduction procedure that allowed the analytical calculation of the fluid boiling temperatures along the experimental test section by applying the ideal mixture assumption and the equilibrium assumption along with Raoult's law. Based on the experimental data, predictive methods for the two-phase pressure drop, the forced convective boiling heat transfer coefficient, and the critical heat flux under engine application conditions were developed. The results summarized in this final project report provide the necessary information for designing and implementing nucleate-boiling vehicular cooling systems.

  16. Repairing sealing surfaces on aluminum castings

    Science.gov (United States)

    Hanna, T. L.

    1980-01-01

    Approach using stylus nickel plating instead of copper and cadmium plating has simplified repair procedure. Damaged sealing surfaces are stylus nickelplated in one step. Superficial scratches and porous areas are removed more easily from repaired surface by simply lapping sealing areas to required finish. Although method is aimed for aerospace components, it may be easily incorporated into conventional aluminumcasting technology. One-step repair can be considered for cast-aluminum automobile and aircraft engines to reduce time and costs.

  17. Femoral hernia repair

    Science.gov (United States)

    Femorocele repair; Herniorrhaphy; Hernioplasty - femoral ... During surgery to repair the hernia, the bulging tissue is pushed back in. The weakened area is sewn closed or strengthened. This repair ...

  18. Undescended testicle repair

    Science.gov (United States)

    Orchidopexy; Inguinal orchidopexy; Orchiopexy; Repair of undescended testicle; Cryptorchidism repair ... first year of life without treatment. Undescended testicle repair surgery is recommended for patients whose testicles do ...

  19. Digital Machining System for Nozzle Cooling Channel of Large Liquid Rocket Engine%大型液体火箭发动机喷管数字化铣槽加工系统

    Institute of Scientific and Technical Information of China (English)

    王永青; 刘海波; 李护林; 贾振元

    2012-01-01

    Rocket nozzle is a key structural part of high-thrust liquid rocket engine. There are a hundreds of cooling channels around the nozzle, to ensure the reliable cooling and preheat the fuel. However, it is very difficult to machine the cooling channel due to large size, complex profile, low rigidity, etc. In this article, an integrated digital method for cooling channel machining composed of profile measuring, data processing and channel milling is proposed. Because of large difference between the actual contour and the design model, the channel bottom should be redesigned by using the measured geometric information. Therefore, the varying-thickness and varying-depth cooling channel of nozzle with high order contour or parametric shapes can be machined. Further, a special digital machining system is developed based on an open numerical control platform for the dual-channel vertical milling machine. Finally, an experiment utilizing a typical rocket nozzle is implemented to verify the feasibility of the system. It has been proved that the digital machining system can meet the machining requirements for liquid rocket engine nozzle.%针对大型液体火箭发动机喷管几何尺寸大、廓形复杂、结构刚度低致使其冷却通道加工质量难以保证的难题,提出一种集“测量-数据处理-铣槽”于一体的喷管冷却通道数字化加工新方法,并在开放式数控平台上开发出喷管专用数字化铣槽加工系统.该方法利用喷管几何外廓的实际测量信息再设计出槽底曲面,进而实现高次曲线或参数曲线廓形、变壁厚变槽深喷管冷却通道的数字化加工.通过某型号火箭发动喷管的实际加工,表明所研制的双通道立式铣槽加工专用装备与系统可满足我国新一代大推力液体火箭发动机喷管冷却通道高质量、高效、高可靠的制造要求.

  20. Cooling technique

    Energy Technology Data Exchange (ETDEWEB)

    Salamon, Todd R; Vyas, Brijesh; Kota, Krishna; Simon, Elina

    2017-01-31

    An apparatus and a method are provided. Use is made of a wick structure configured to receive a liquid and generate vapor in when such wick structure is heated by heat transferred from heat sources to be cooled off. A vapor channel is provided configured to receive the vapor generated and direct said vapor away from the wick structure. In some embodiments, heat conductors are used to transfer the heat from the heat sources to the liquid in the wick structure.

  1. Research Progress of Tissue-engineered Cartilage to Repair Articular Cartilage Damage in Western and Chinese Medicine%组织工程软骨修复关节软骨损伤中西医研究进展

    Institute of Scientific and Technical Information of China (English)

    陈强; 蔡建平; 张爱国

    2012-01-01

    Articular cartilage damage and repair have been the thorny issue of orthopedic basic research and clinical treatment. Articular cartilage damage is becoming increasingly prominent, and has become a serious challenge faced by the multi-disciplinary trauma surgery, orthopedics, elderly subjects, as well as sports medicine. In this paper, the articular cartilage damage repair status, the tissue-engineered cartilage and Chinese medicine were made an overview of research on tissue engineered cartilage.%关节软骨的损伤和修复,一直以来是骨科基础研究与临床治疗的棘手问题.关节软骨损伤问题日益突出,俨然成为创伤外科、骨科、老年学科以及运动医学等多学科面临的严峻挑战.文章就关节软骨损伤修复现状、组织工程软骨技术及中药在组织工程软骨中的研究三方面做一概述.

  2. Study on the Cooling System of the Engine with the Solution of Calcium Chloride%以氯化钙溶液为冷却液的发动机冷却系统研究

    Institute of Scientific and Technical Information of China (English)

    乔亚宾; 朱鑫宇; 马兴远

    2015-01-01

    According to the solution, the boiling point of the solution is higher than that of the organic solvent, and the freezing point is lower than the organic solvent solution. Through the study of the physical properties of the calcium chloride solution, combined with the popular ethylene glycol type cooling liquid, the feasibility of the solution is studied. Calcium chloride solution has a certain corrosion, the engine cooling system is made of new material, the theoretical performance analysis and experimental results show that the use of suitable calcium chloride solution can replace ethylene glycol type coolant, as a new type of engine cooling liquid.%根据溶液的依数性可知,相同浓度的溶液,电解质溶液的沸点高于有机溶剂溶液,冰点低于有机溶剂溶液,更符合发动机冷却系统对冷却液的基本要求。通过对氯化钙溶液物性的研究,结合市面上流行的乙二醇型冷却液的性能,探究氯化钙溶液作为车用冷却液的可行性。氯化钙溶液有一定的腐蚀性,采用新材料制作的发动机冷却系统,通过材料的理论性能分析和实验结果表明,采用合适的技术氯化钙溶液完全可以替代乙二醇型冷却液,作为新型的发动机冷却液使用。

  3. 液体火箭发动机液膜冷却研究综述%Review of Research on Liquid Film Cooling for Liquid-propellant Rocket Engine

    Institute of Scientific and Technical Information of China (English)

    周红玲; 杨成虎; 刘犇

    2012-01-01

    液膜冷却对降低燃烧室和喷注器头部温度有显著作用,而且通道结构比较简单,因此在载人航天液体推进系统用姿轨控发动机中得到了广泛应用。液膜冷却的传热过程主要包括对流传热和沸腾传热两种形式,传质过程主要包括液膜的蒸发和中心主气流对液膜的携带。对液膜冷却过程的研究工作进行了综述,讨论了液膜冷却的异常升温现象和发生机理。%Liquid film cooling is widely used in attitude and ahitude liquid rocket engine for manned spaceflight propulsion sys- tem. With a comparatively simple channel structure, it is an effective method to protect the combustor and injector from high temperature. The two main heat transfer patterns in liquid film cooling are convection transfer and boiling heat transfer, while the process of mass transfer mainly includes liquid film evaporating and the carrying of the film by main flow. Research on the heat and mass transfer during liquid film cooling is reviewed, and the phenomenon and mecha- nism of abnormal temperature rise of liquid film cooling are discussed.

  4. Erosion Resistant Compressor Blade Repair Technologies Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase I SBIR program will demonstrate the use of wear resistant high strength nanocomposites in the turbine engine repair and refurbishment process. The...

  5. 半月板运动性损伤的组织工程修复:国际研究趋势与未来%Tissue-engineered repair of exercise-induced meniscal injury: International research trends and future

    Institute of Scientific and Technical Information of China (English)

    杨小宁

    2012-01-01

    BACKGROUND: The depth study of disciplines, such as tissue engineering, genetic engineering, biomechanics and materials science, provides a new approach for the treatment of meniscal injuries.OBJECTIVE: To multivariately analyze the literatures on the tissue-engineered repair of exercise-induced meniscal injury through Scopus database and to summarize the application progress of tissue-engineered repair of exercise-induced meniscal injury.METHODS: A retrieval was performed for the literature of the tissue-engineered repair of exercise-induced meniscal injury, using the key words of "meniscus, sports injuries, tissue engineering, repair" between January 2002 and December 2011 in Scopus database. The retrieval results were analyzed, and the trends were described in words and graphics.RESULTS AND CONCLUSION: A total of 245 literatures on the issue-engineered repair of exercise-induced meniscal injury were retrieved in Scopus database, in which most of paper were published as original articles. Eight articles were identified as classic literatures. The overall number of literature had an upward trend from 2002 to 2011. United States and England published more literature than other countries, which play an important role in the field of tissue-engineered repair of exercise-induced meniscal injury. Most of literatures were published from Rice University, University of Pennsylvania, and Radboud University Nijmegen Medical Centre. Biomaterials published most papers in this field (n=15, 6.12%). This paper provides a valuable reference for researchers to understand the overview and present situation of this field.%背景:骨组织工程学、基因工程、生物力学以及材料学等学科研究的深入,为半月板损伤的治疗提供了新途径.目的:利用Scopus数据库文献检索和深度分析功能,对于半月板运动损伤的组织工程修复的文献资料趋势进行多层次探讨分析,总结半月板运动损伤的组织工程修复的应用进展.

  6. 冲压进气冷却对发动机舱温度分布的影响%Impact of Ram Air Inlet Cooling on Temperature Distribution of Aero-Engine Compartment

    Institute of Scientific and Technical Information of China (English)

    马松; 李堃; 张志伟; 王占学

    2014-01-01

    冲压进气冷却是目前控制战斗机发动机舱内温度分布的主要方式。利用基于模型的发动机性能分析方法,提供不同工况下发动机分段热壁边界条件,通过非结构化网格和k-ε湍流模型方法求解流动与传热控制方程,数值模拟了某型发动机舱在典型飞行状态和发动机工况下的流动特征及流场关键参数分布,并与试验结果进行了对比分析。结果表明,模拟结果与试验结果吻合良好,模拟方法能准确预测发动机舱温度场分布,为通风冷却系统和灭火系统的设计与优化提供依据。%Ram air inlet cooling is the main way to control the fighter engine compartment temperature dis-tribution. Based on the model of the engine performance under different working conditions, engine block hot wall boundary conditions were provided. By means of the unstructured grid and k-ε turbulent model method, the flow and heat transfer control equations were solved. The flow characteristics of key parameters and flow field distribution of a certain type of engine compartment in a typical flight condition and engine working conditions were simulated and compared with the test results. The results show that the simulation results agree with test results and the method can accurately forecast engine compartment temperature field distribution that will provide a scientific basis for ventilation cooling system and fire extinguishing system design and optimization.

  7. Intestinal obstruction repair

    Science.gov (United States)

    Repair of volvulus; Intestinal volvulus - repair; Bowel obstruction - repair ... Intestinal obstruction repair is done while you are under general anesthesia . This means you are asleep and DO NOT feel pain. ...

  8. Aortic aneurysm repair - endovascular

    Science.gov (United States)

    EVAR; Endovascular aneurysm repair - aorta; AAA repair - endovascular; Repair - aortic aneurysm - endovascular ... Endovascular aortic repair is done because your aneurysm is very large, growing quickly, or is leaking or bleeding. You may have ...

  9. Motorcycle Repair.

    Science.gov (United States)

    Hein, Jim; Bundy, Mike

    This motorcycle repair curriculum guide contains the following ten areas of study: brake systems, clutches, constant mesh transmissions, final drives, suspension, mechanical starting mechanisms, electrical systems, fuel systems, lubrication systems, and overhead camshafts. Each area consists of one or more units of instruction. Each instructional…

  10. Solar heat utilization for adsorption cooling device

    Directory of Open Access Journals (Sweden)

    Malcho Milan

    2012-04-01

    Full Text Available This article deals with possibility of solar system connection with adsorption cooling system. Waste heat from solar collectors in summer is possible to utilize in adsorption cooling systems, which desorption temperatures have to be lower than temperature of heat transport medium operation temperature. For verification of work of this system was constructed on the Department of power engineering on University of Zilina solar adsorption cooling device.

  11. Numerical Simulation and Improvement on Cavitation Performance of Engine Cooling Water Pump%发动机冷却水泵空化特性的数值模拟与改进

    Institute of Scientific and Technical Information of China (English)

    李伟; 施卫东; 裴冰; 张华; 陆伟刚

    2013-01-01

    Cavitation of engine cooling water pump is a main factor for noise and vibration, and decreasing service time of automotive cooling system. To improve the anti-cavitation performance of engine cooling water pump, the three-dimensional turbulent flow in cooling pump was simulated employing the time averaged N-S equation, the standard k-e two equation turbulent model and multiphase flow model of CFX software. Cavitation flow distribution in the impeller of cooling water pump was observed. Compared with experimental data, the experimental head of the pump is 6.1 m at the design flow rate of 285 L/min, which is lower than that of numerical simulation under room temperature. Serious cavitation occurs under actual operating conditions. Experimental NPSH of the pump is 9.8 m at 85 ℃, which is consistent with the simulation results. Two methods that slow cavitation of engine cooling water pump were proposed. They can improve the cavitation performance. Anti-cavitation performance is improved with reducing blade number.%发动机冷却水泵的空化破坏是缩短汽车冷却系统寿命、产生振动噪声等危害的关键因素.为了提高发动机冷却水泵的抗汽蚀性能,以时均N-S方程作为基本控制方程,采用标准k-ε双方程湍流模型及多相流模型,利用CFX流体计算软件模拟了发动机冷却水泵内部的三维湍流,并观察叶轮内部空化流场的分布.通过试验对比验证,水泵在285 L/min设计流量下扬程为6.1m,远远低于常温下的数值模拟扬程,说明该泵在实际运行工况下已发生严重空化;在85℃下,模型泵试验汽蚀余量为9.8 m,与数值计算结果基本一致,说明数值计算结果是可靠的.并由此提出了两种减缓发动机冷却水泵发生空化的有效方法,两种方案均能较好改善泵的空化性能,且减少叶片数方案抗汽蚀性能更优.

  12. Turbine repair process, repaired coating, and repaired turbine component

    Energy Technology Data Exchange (ETDEWEB)

    Das, Rupak; Delvaux, John McConnell; Garcia-Crespo, Andres Jose

    2015-11-03

    A turbine repair process, a repaired coating, and a repaired turbine component are disclosed. The turbine repair process includes providing a turbine component having a higher-pressure region and a lower-pressure region, introducing particles into the higher-pressure region, and at least partially repairing an opening between the higher-pressure region and the lower-pressure region with at least one of the particles to form a repaired turbine component. The repaired coating includes a silicon material, a ceramic matrix composite material, and a repaired region having the silicon material deposited on and surrounded by the ceramic matrix composite material. The repaired turbine component a ceramic matrix composite layer and a repaired region having silicon material deposited on and surrounded by the ceramic matrix composite material.

  13. ATLAS - Liquid Cooling Systems

    CERN Multimedia

    Bonneau, P.

    1998-01-01

    Photo 1 - Cooling Unit - Side View Photo 2 - Cooling Unit - Detail Manifolds Photo 3 - Cooling Unit - Rear View Photo 4 - Cooling Unit - Detail Pump, Heater and Exchanger Photo 5 - Cooling Unit - Detail Pump and Fridge Photo 6 - Cooling Unit - Front View

  14. Analysis on Application Bottleneck of Repairing Bone Defects with Tissue Engineered Bone%组织工程骨修复骨缺损的应用瓶颈分析

    Institute of Scientific and Technical Information of China (English)

    李凯

    2012-01-01

    Bone defects caused by bone cancer treatment are common in clinical, however the only way to repair the defects is bone graft. According to sources, the bone graft material can be divided into autogenous bone, allograft bone ,xenograft bone and artificial bone substitute materials. The rise of bone tissue engineering brings new options for the treatment of bone defects. The use of artificial bone tissue engineering training not only fixes the large area of bone defect, but also can be prepared and shaped in large quantity according to need,which makes it an ideal bone repair material. Here is to make a review' on the application status of tissue engineered bone in the treatment of bone defects.%骨肿瘤的治疗导致骨缺损很常见,修复缺损的方法是采取骨移植.骨移植材料根据来源大致可分为自体骨、同种异体骨、异种骨和人工骨替代材料.骨组织工程的兴起为骨缺损的治疗带来新的选择.利用骨组织工程培养的人工骨不仅可以修复大面积骨缺损,而且可以按需塑形并大量制备,是一种理想的骨修复材料.现就组织工程骨在治疗骨缺损中的应用现状进行综述.

  15. Nano surface engineering and remanufacture engineering

    Institute of Scientific and Technical Information of China (English)

    XU Bin-shi

    2004-01-01

    Nano surface engineering and remanufacture engineering are introduced, and the relationship between them is set forth. It points out the superiority of nano surface engineering to the traditional one, and reveals the advantages of remanufacture engineering. Taking some nano surface techniques as samples, such as nano-materials brush electroplating, nano-materials thermal spraying and nano-materials self-repairing antifriction additive technology, it shows the applications of nano surface engineering technology to remanufacturing mechanical parts.

  16. JKD - R40A1SS 冷却循环水系统的维护和修理%Maintenance and repair of JKD-R40A1SS cooling water recirculation system

    Institute of Scientific and Technical Information of China (English)

    邓志刚; 牟善彬

    2013-01-01

    The working condition of cooling water recirculation system directly affects the service life of electronic microscope.And the working condition can not be separated from the daily maintenance.%冷却循环水系统工作好坏直接影响到电镜的使用寿命,系统工作是否正常与平时做好维护是分不开的。

  17. Concrete structures protection, repair and rehabilitation

    CERN Document Server

    Woodson, R Dodge

    2009-01-01

    The success of a repair or rehabilitation project depends on the specific plans designed for it. Concrete Structures: Protection, Repair and Rehabilitation provides guidance on evaluating the condition of the concrete in a structure, relating the condition of the concrete to the underlying cause or causes of that condition, selecting an appropriate repair material and method for any deficiency found, and using the selected materials and methods to repair or rehabilitate the structure. Guidance is also provided for engineers focused on maintaining concrete and preparing concrete investigation r

  18. Turbine airfoil with laterally extending snubber having internal cooling system

    Science.gov (United States)

    Scribner, Carmen Andrew; Messmann, Stephen John; Marsh, Jan H.

    2016-09-06

    A turbine airfoil usable in a turbine engine and having at least one snubber with a snubber cooling system positioned therein and in communication with an airfoil cooling system is disclosed. The snubber may extend from the outer housing of the airfoil toward an adjacent turbine airfoil positioned within a row of airfoils. The snubber cooling system may include an inner cooling channel separated from an outer cooling channel by an inner wall. The inner wall may include a plurality of impingement cooling orifices that direct impingement fluid against an outer wall defining the outer cooling channel. In one embodiment, the cooling fluids may be exhausted from the snubber, and in another embodiment, the cooling fluids may be returned to the airfoil cooling system. Flow guides may be positioned in the outer cooling channel, which may reduce cross-flow by the impingement orifices, thereby increasing effectiveness.

  19. Paracrine Engineering of Human Explant-Derived Cardiac Stem Cells to Over-Express Stromal-Cell Derived Factor 1α Enhances Myocardial Repair.

    Science.gov (United States)

    Tilokee, Everad L; Latham, Nicholas; Jackson, Robyn; Mayfield, Audrey E; Ye, Bin; Mount, Seth; Lam, Buu-Khanh; Suuronen, Erik J; Ruel, Marc; Stewart, Duncan J; Davis, Darryl R

    2016-07-01

    First generation cardiac stem cell products provide indirect cardiac repair but variably produce key cardioprotective cytokines, such as stromal-cell derived factor 1α, which opens the prospect of maximizing up-front paracrine-mediated repair. The mesenchymal subpopulation within explant derived human cardiac stem cells underwent lentiviral mediated gene transfer of stromal-cell derived factor 1α. Unlike previous unsuccessful attempts to increase efficacy by boosting the paracrine signature of cardiac stem cells, cytokine profiling revealed that stromal-cell derived factor 1α over-expression prevented lv-mediated "loss of cytokines" through autocrine stimulation of CXCR4+ cardiac stem cells. Stromal-cell derived factor 1α enhanced angiogenesis and stem cell recruitment while priming cardiac stem cells to readily adopt a cardiac identity. As compared to injection with unmodified cardiac stem cells, transplant of stromal-cell derived factor 1α enhanced cells into immunodeficient mice improved myocardial function and angiogenesis while reducing scarring. Increases in myocardial stromal-cell derived factor 1α content paralleled reductions in myocyte apoptosis but did not influence long-term engraftment or the fate of transplanted cells. Transplantation of stromal-cell derived factor 1α transduced cardiac stem cells increased the generation of new myocytes, recruitment of bone marrow cells, new myocyte/vessel formation and the salvage of reversibly damaged myocardium to enhance cardiac repair after experimental infarction. Stem Cells 2016;34:1826-1835.

  20. Design and Research on Engine Cooling Fan Based on Bladeless Fan%基于无扇叶风扇的发动机冷却风扇的设计研究

    Institute of Scientific and Technical Information of China (English)

    张鹏程; 董小瑞; 王强; 石运才

    2016-01-01

    Bladeless fan can increase mass flow of the inlet markedly.A new designed cooling fan based on air multiplier fan was applied to the car engine cooling system and simulated to observe cooling effect. The 3D model of the cooling fan was analyzed by Fluent software to get the situation of the air flow and mass flow.The length of adhesion surface and the outside dip angle are two important parameters for bl-adeless fan.And the law of outlet massflow with these two parameters was gotten through simulation. A simplified model of a radiator was launched to test the effect of the cooling fan.The results indicate that the temperature of the radiator dropped by 10 ℃ at the speed of inlet air with 20 m/s.The effect of heat dissipation is obvious.%无扇叶风扇可显著增加进风口的流量,将其应用于汽车发动机冷却系统,通过仿真分析其送风性能和冷却效果。首先对冷却风扇的三维模型使用 Fluent软件进行流体仿真以分析空气流动情况并得到出风量。扩散面长度和外侧倾角这两个参数对风扇的送风性能有较大的影响,通过仿真计算获得了出口流量随这两参数的变化规律。最后建立了散热器的简化模型并检验冷却风扇的散热效果,结果表明在进风为20 m/s 的速度下,散热器温度降低约10℃,散热效果明显。

  1. 46 CFR 35.25-5 - Repairs of boilers and unfired pressure vessels and reports of repairs or accidents by chief...

    Science.gov (United States)

    2010-10-01

    ... reports of repairs or accidents by chief engineer-TB/ALL. 35.25-5 Section 35.25-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS OPERATIONS Engine Department § 35.25-5 Repairs of boilers and unfired pressure vessels and reports of repairs or accidents by chief engineer—TB/ALL. (a) Before...

  2. Repairing the wooden frame of chambers in coking furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Nador, Y.; Iruti, M.; Komiya, S.; Matsuno, T.; Ogavakhara, F.

    1983-02-12

    A method and device are proposed for hot repair of the door frames of coking chanbers. The repair is conducted prior to discharge of the coke from the chamber without its cooling or a reduction in temperature. After the doors are removed, a screening plate fettled with a heat insulation material on the chamber side is introduced into the frame, it is attached to the door frame and the required repair is conducted.

  3. Solar heating and cooling.

    Science.gov (United States)

    Duffie, J A; Beckman, W A

    1976-01-16

    We have adequate theory and engineering capability to design, install, and use equipment for solar space and water heating. Energy can be delivered at costs that are competitive now with such high-cost energy sources as much fuel-generated, electrical resistance heating. The technology of heating is being improved through collector developments, improved materials, and studies of new ways to carry out the heating processes. Solar cooling is still in the experimental stage. Relatively few experiments have yielded information on solar operation of absorption coolers, on use of night sky radiation in locations with clear skies, on the combination of a solar-operated Rankine engine and a compression cooler, and on open cycle, humidification-dehumidification systems. Many more possibilities for exploration exist. Solar cooling may benefit from collector developments that permit energy delivery at higher temperatures and thus solar operation of additional kinds of cycles. Improved solar cooling capability can open up new applications of solar energy, particularly for larger buildings, and can result in markets for retrofitting existing buildings. Solar energy for buildings can, in the next decade, make a significant contribution to the national energy economy and to the pocketbooks of many individual users. very large-aggregate enterprises in manufacture, sale, and installation of solar energy equipment can result, which can involve a spectrum of large and small businesses. In our view, the technology is here or will soon be at hand; thus the basic decisions as to whether the United States uses this resource will be political in nature.

  4. Cool visitors

    CERN Multimedia

    2006-01-01

    Pictured, from left to right: Tim Izo (saxophone, flute, guitar), Bobby Grant (tour manager), George Pajon (guitar). What do the LHC and a world-famous hip-hop group have in common? They are cool! On Saturday, 1st July, before their appearance at the Montreux Jazz Festival, three members of the 'Black Eyed Peas' came on a surprise visit to CERN, inspired by Dan Brown's Angels and Demons. At short notice, Connie Potter (Head of the ATLAS secretariat) organized a guided tour of ATLAS and the AD 'antimatter factory'. Still curious, lead vocalist Will.I.Am met CERN physicist Rolf Landua after the concert to ask many more questions on particles, CERN, and the origin of the Universe.

  5. Optimization of the engineering design for the Lansing District Cooling System by comparative analysis of the impact of advanced technologies on a conventional design approach. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    The Lansing Board of Water and Light (LBWL) began investigating development of a cooling district in the Lansing Downtown in 1989 in order to retain and build summer load for its steam utility. A feasibility study was conducted in conjunction with SFT, Inc. and ZBA, Inc. which addressed many factors such as marketability of the product, impact on the summer steam load, distribution system development, system design, probable capital and operating costs, reliability and environmental and other regulatory impacts on a preliminary feasibility basis. The Phase I study completed in September of 1989 provided highly promising results for establishing a District Cooling System (DCS). An existing chilled water production facility owned by the State of Michigan was identified as a potential location for a DCS plant. With these changes a review of the feasibility with a new set of alternatives and sensitivities was evaluated. This enhancement to the Phase I Study was nearing completion when the LBWL in conjunction with Energy, Mines and Resources Canada proposed to conduct the Phase II project in conjunction with DOE. The project was structured to proceed along a dual track to demonstrate the impact of the application of various innovative technologies.

  6. Numerical simulation of fluid field and in vitro three-dimensional fabrication of tissue-engineered bones in a rotating bioreactor and in vivo implantation for repairing segmental bone defects.

    Science.gov (United States)

    Song, Kedong; Wang, Hai; Zhang, Bowen; Lim, Mayasari; Liu, Yingchao; Liu, Tianqing

    2013-03-01

    In this paper, two-dimensional flow field simulation was conducted to determine shear stresses and velocity profiles for bone tissue engineering in a rotating wall vessel bioreactor (RWVB). In addition, in vitro three-dimensional fabrication of tissue-engineered bones was carried out in optimized bioreactor conditions, and in vivo implantation using fabricated bones was performed for segmental bone defects of Zelanian rabbits. The distribution of dynamic pressure, total pressure, shear stress, and velocity within the culture chamber was calculated for different scaffold locations. According to the simulation results, the dynamic pressure, velocity, and shear stress around the surface of cell-scaffold construction periodically changed at different locations of the RWVB, which could result in periodical stress stimulation for fabricated tissue constructs. However, overall shear stresses were relatively low, and the fluid velocities were uniform in the bioreactor. Our in vitro experiments showed that the number of cells cultured in the RWVB was five times higher than those cultured in a T-flask. The tissue-engineered bones grew very well in the RWVB. This study demonstrates that stress stimulation in an RWVB can be beneficial for cell/bio-derived bone constructs fabricated in an RWVB, with an application for repairing segmental bone defects.

  7. Shuttle Repair Tools Automate Vehicle Maintenance

    Science.gov (United States)

    2013-01-01

    Successfully building, flying, and maintaining the space shuttles was an immensely complex job that required a high level of detailed, precise engineering. After each shuttle landed, it entered a maintenance, repair, and overhaul (MRO) phase. Each system was thoroughly checked and tested, and worn or damaged parts replaced, before the shuttle was rolled out for its next mission. During the MRO period, workers needed to record exactly what needed replacing and why, as well as follow precise guidelines and procedures in making their repairs. That meant traceability, and with it lots of paperwork. In 2007, the number of reports generated during electrical system repairs was getting out of hand-placing among the top three systems in terms of paperwork volume. Repair specialists at Kennedy Space Center were unhappy spending so much time at a desk and so little time actually working on the shuttle. "Engineers weren't spending their time doing technical work," says Joseph Schuh, an electrical engineer at Kennedy. "Instead, they were busy with repetitive, time-consuming processes that, while important in their own right, provided a low return on time invested." The strain of such inefficiency was bad enough that slow electrical repairs jeopardized rollout on several occasions. Knowing there had to be a way to streamline operations, Kennedy asked Martin Belson, a project manager with 30 years experience as an aerospace contractor, to co-lead a team in developing software that would reduce the effort required to document shuttle repairs. The result was System Maintenance Automated Repair Tasks (SMART) software. SMART is a tool for aggregating and applying information on every aspect of repairs, from procedures and instructions to a vehicle s troubleshooting history. Drawing on that data, SMART largely automates the processes of generating repair instructions and post-repair paperwork. In the case of the space shuttle, this meant that SMART had 30 years worth of operations

  8. Use of groundwater for heating and cooling. A hotel with an ecological building services engineering; Grundwassernutzung fuer Heizung und Kuehlung. Ein Hotel mit oekologischer Gebaeudetechnik

    Energy Technology Data Exchange (ETDEWEB)

    Edel, Alexander [conplaning GmbH, Ulm (Germany); Lauster, Marcus

    2010-07-01

    Renewable energies and environmental compatibility were the main considerations in the construction of the new conference hotel ''Lago'' in direct proximity to the exhibition grounds of Ulm (Federal Republic of Germany). The hotel in idyllic location at the lake Au was built with predominantly natural minerals and equipped with ecologically compatible building services engineering.

  9. Solar engineering - 1981; Proceedings of the Third Annual Conference on Systems Simulation, Economic Analysis/Solar Heating and Cooling Operational Results, Reno, NV, April 27-May 1, 1981

    Science.gov (United States)

    Reid, R. L.; Murphy, L. M.; Ward, D. S.

    Progress made toward the commercialization of solar energy technologies as of 1981 is assessed, and attention is given to the future uses and impacts of solar energy. Attention is given to the results of several years of monitoring and modifying solar heating and cooling on residential and commercial structures. Solar system simulation and analysis methods are reviewed, covering the performance and operations of passive and active systems, thermosyphon systems, heat pumps and phase change systems. Simulations of system components are discussed, as are means to validate existing computer simulation codes, particularly the TRNSYS program. Control systems and logic for collector systems are explored, including analyses of building loads and climates, and numerical models of the economics of solar heating systems are presented. Performance simulations and economic analyses are also outlined for wind and photovoltaic systems, and for industrial solar heating systems. Finally, fundamental studies of corrosion, steam flow, wind loading, and scaling in solar systems are described.

  10. PERFORMANCE, EMISSION AND COMBUSTION CHARACTERISTICS OF A METHYL ESTER SUNFLOWER OILEUCALYPTUS OIL IN A SINGLE CYLINDER AIR COOLED AND DIRECT INJECTION DIESEL ENGINE

    Directory of Open Access Journals (Sweden)

    TAMILVENDHAN.D,

    2011-03-01

    Full Text Available Biomass derived fuels are preferred as alternative fuels for IC engine due to its abundant availability and renewable nature. In the present work the performance, emission and combustion characteristics of a single cylinder constant speed , direct injection diesel engine using methyl ester of sun flower oil – eucalyptus oil blend as an alternative fuel were studied and the results are compared with thestandard diesel fuel operation. Result indicated that 50% reduction in smoke, 34% reduction in HC emission and a 37.5% reduction in CO emission for the MeS50Eu50 blend with 2.8 % increase in NOx emission at full load. Brake thermal efficiency was increased 2.7 % for eS50Eu50 blend.

  11. 可视化钠冷快堆工程信息系统的研究和设计%Viewing Sodium Cooled Fast Reactor Research and Design Engineering Information Systems

    Institute of Scientific and Technical Information of China (English)

    林全兵

    2014-01-01

    October 24, 2012, the State Council approved the "Nuclear Security Plan (2011-2020)" and "long-term nuclear power development plan (2011-2020)." This means that since the Fukushima nuclear leak in Japan since shut down the nuclear power project in China for nearly 20 months after the last full restart. Nuclear construction and re-enter the fast track scale development, on the basis of the domestic and international nuclear power project management systems, 3D visualization techniques designed to analyze the results of relevant research studies, combined with the characteristics of the sodium cooled fast reactor construction project information system application information integration technology to build a visual sodium-cooled fast reactor engineering information systems management platform to meet the use of nuclear power construction project management unit. Establish the visual content of the paper on sodium-cooled fast reactor engineering information platform has universal reference and high practical value.%2012年10月24日,国务院常务会议讨论通过了《核电安全规划(2011-2020年)》和《核电中长期发展规划(2011-2020年)》。这意味着,自日本发生福岛核泄漏以来,停摆了近20个月之后的中国核电项目终于全面重启。核电建造又重新进入了快速规模化发展的轨道,本文在对国内外核电项目管理系统、三维可视化设计技术相关研究成果进行分析研究的基础上,结合钠冷快堆工程信息系统的施工特点,应用信息集成技术,建设一个可视化的钠冷快堆工程信息系统管理平台,满足核电建造单位项目管理使用。本文的内容对可视化钠冷快堆工程信息平台的建立有普遍的借鉴意义和较高的实用价值。

  12. CoolPack – Simulation tools for refrigeration systems

    DEFF Research Database (Denmark)

    Jakobsen, Arne; Rasmussen, Bjarne D.; Andersen, Simon Engedal

    1999-01-01

    CoolPack is a collection of programs used for energy analysis and optimisation of refrigeration systems. CoolPack is developed at the Department of Energy Engineering at the Technical University of Denmark. The Danish Energy Agency finances the project. CoolPack is freeware and can be downloaded...

  13. 46 CFR 78.33-1 - Repairs of boiler and pressure vessels.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Repairs of boiler and pressure vessels. 78.33-1 Section... OPERATIONS Reports of Accidents, Repairs, and Unsafe Equipment § 78.33-1 Repairs of boiler and pressure vessels. (a) Before making any repairs to boilers or unfired pressure vessels, the chief engineer...

  14. Advanced Combustor Liner Cooling Technology for Gas Turbines

    Directory of Open Access Journals (Sweden)

    Aspi R. Wadia

    1988-10-01

    Full Text Available This paper briefly reviews some of the work on advanced liner cooling techniques - specificially laminated porous wall cooling, angled-multihole (effusion cooling and composite metal matrix liner cooling. The concept definition, heat transfer design procedure and design problems including key materials and fabrication considerations associated with each basic concept will be reviewed. Published rig and engine experience of aircraft engine manufacturers and research organizations will be cited. Some logical extensions of the current liner cooling schemes are suggested for future applications.

  15. Sequential cooling insert for turbine stator vane

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Russel B

    2017-04-04

    A sequential flow cooling insert for a turbine stator vane of a small gas turbine engine, where the impingement cooling insert is formed as a single piece from a metal additive manufacturing process such as 3D metal printing, and where the insert includes a plurality of rows of radial extending impingement cooling air holes alternating with rows of radial extending return air holes on a pressure side wall, and where the insert includes a plurality of rows of chordwise extending second impingement cooling air holes on a suction side wall. The insert includes alternating rows of radial extending cooling air supply channels and return air channels that form a series of impingement cooling on the pressure side followed by the suction side of the insert.

  16. Performance analysis of adiabatic engine

    Energy Technology Data Exchange (ETDEWEB)

    Sudhakar, V.

    1984-01-01

    As the development of the adiabatic diesel engine continues with a goal of 65% reduction in net in-cylinder heat transfer over a cooled engine, several uncooled engines with intermediate levels of reduced heat transfer were studied. Some aspects and results of the adiabatic diesel engine cycle simulation are discussed. Performance test data and simulation results are compared for a conventionally cooled and uncooled Cummins NH-450 turbocompound engines. Exhaust emissions were also measured and compared.

  17. Eye muscle repair - discharge

    Science.gov (United States)

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  18. Ventral hernia repair

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/007661.htm Ventral hernia repair To use the sharing features on this page, please enable JavaScript. Ventral hernia repair is surgery to repair a ventral hernia. ...

  19. Brain aneurysm repair

    Science.gov (United States)

    ... aneurysm repair; Dissecting aneurysm repair; Endovascular aneurysm repair - brain; Subarachnoid hemorrhage - aneurysm ... Your scalp, skull, and the coverings of the brain are opened. A metal clip is placed at ...

  20. The Shandong Shidao Bay 200 MWe High-Temperature Gas-Cooled Reactor Pebble-Bed Module (HTR-PM Demonstration Power Plant: An Engineering and Technological Innovation

    Directory of Open Access Journals (Sweden)

    Zuoyi Zhang

    2016-03-01

    Full Text Available After the first concrete was poured on December 9, 2012 at the Shidao Bay site in Rongcheng, Shandong Province, China, the construction of the reactor building for the world's first high-temperature gas-cooled reactor pebble-bed module (HTR-PM demonstration power plant was completed in June, 2015. Installation of the main equipment then began, and the power plant is currently progressing well toward connecting to the grid at the end of 2017. The thermal power of a single HTR-PM reactor module is 250 MWth, the helium temperatures at the reactor core inlet/outlet are 250/750 °C, and a steam of 13.25 MPa/567 °C is produced at the steam generator outlet. Two HTR-PM reactor modules are connected to a steam turbine to form a 210 MWe nuclear power plant. Due to China's industrial capability, we were able to overcome great difficulties, manufacture first-of-a-kind equipment, and realize series major technological innovations. We have achieved successful results in many aspects, including planning and implementing R&D, establishing an industrial partnership, manufacturing equipment, fuel production, licensing, site preparation, and balancing safety and economics; these obtained experiences may also be referenced by the global nuclear community.

  1. Simulation on Cooling System of Automotive Waste Heat Thermoelectric Generator

    Directory of Open Access Journals (Sweden)

    Xiaohong Yuan

    2013-06-01

    Full Text Available The cooling system of automobile waste heat Thermoelectric Generator (TEG is researched in the study. Integrated model of cooling system and vehicle is built based on GT-Cool, analysis of the different cooling ways shows that when using independent cooling system, the ratio between power consumption and output is high and system performance is poor; By using integrated cooling system, the expectation of keep constant engine warm up time and synchronous change of water temperature between different tanks is realized after water tanks are improved.

  2. Industrial stator vane with sequential impingement cooling inserts

    Science.gov (United States)

    Jones, Russell B; Fedock, John A; Goebel, Gloria E; Krueger, Judson J; Rawlings, Christopher K; Memmen, Robert L

    2013-08-06

    A turbine stator vane for an industrial engine, the vane having two impingement cooling inserts that produce a series of impingement cooling from the pressure side to the suction side of the vane walls. Each insert includes a spar with a row of alternating impingement cooling channels and return air channels extending in a radial direction. Impingement cooling plates cover the two sides of the insert and having rows of impingement cooling holes aligned with the impingement cooling channels and return air openings aligned with the return air channel.

  3. 自体红骨髓构建非细胞型组织工程化骨修复骨缺损%Repairing bone defects by non-cell based tissue engineered complex constructed by autologous red bone marrow

    Institute of Scientific and Technical Information of China (English)

    黄文良; 邓江; 贾东林; 阮世强; 苑成

    2012-01-01

    BACKGROUND: Cell based tissue engineered bone is successful in the repair of bone defects, but it is a complex operation,easy to be contaminated and takes a long time, and not conducive to clinical application.OBJECTIVE: To investigate the efficacy of repairing large-segment bone defects by non-cell based tissue engineered complexconstructed by autologous red bone marrow.METHODS: Twenty-seven rabbits were used to prepare 2 cm unilateral radial large-segment bone defect models, and thenrandomly divided into group A, group B and group C. Group A was implanted with autologous red bone marrow to constructtissue engineered bone (autologous red bone marrow+recombinant human insulin-like growth factor-1/coralline hydroxyapatite);group B was implanted with autologous red bone marrow/coralline hydroxyapatite artificial bone material; group C was implantedwith coralline hydroxyapatite/recombinant human insulin-like growth factor-1 artificial bone material.RESULTS AND CONCLUSION: Group A was superior to the other two group in terms of osteogenic potential and materialdegradation by comparison of degree of bone formation, bone trabecular number, the structure formation of mature bone andimplant degradation at 4, 8, 12 weeks after implantation (P < 0.05). Non-cell based tissue engineered bone constructed byautologous red bone marrow has better osteogenic activity, and effective to repair large-segment bone defects.%背景:细胞型组织工程化骨修复骨缺损的效果良好,但存在操作复杂,容易污染及花费时间长等不足,不利于临床应用.目的:观察自体红骨髓构建的非细胞型组织工程化骨修复大段骨缺损的成骨效果.方法:在27只家兔一侧桡骨制作2 cm大段骨缺损模型后,随机分3组,分别植入自体红骨髓+重组人胰岛素样生长因子1/珊瑚羟基磷灰石非细胞型组织工程化骨、自体红骨髓/珊瑚羟基磷灰石复合人工骨材料、珊瑚羟基磷灰石/重组人胰岛素样生长因子1复

  4. Tissue-engineered nerve for repair of peripheral nerve injuries%组织工程化神经修复周围神经创伤的应用

    Institute of Scientific and Technical Information of China (English)

    傅重洋; 赵佳; 曲巍

    2013-01-01

    BACKGROUND:Recent development of bioengineering technology and tissue-engineered nerve brings a new hope for the treatment of peripheral nerve injuries, which has gradual y become a research spot. OBJECTIVE:To review the new progress in the repair of peripheral nerve injuries using seed cells, biomaterials and tissue-engineered nerve construction technology. METHODS:PubMed and CNKI were searched by the first authors for articles concerning nerve tissue engineering and repair of peripheral nerve injuries published prior to July 2013. The keywords were“tissue engineering, peripheral nerves, nerve injuries, stem cells, Schwann cells, scaffold, growth factor”in English and Chinese, respectively. The articles published recently or in the authorized journals were preferred in the same field. Final y, 63 articles were included in result analysis. RESULTS AND CONCLUSION:Up to now, there is a great advance in the tissue engineering technology for the repair of peripheral nerve injuries. However, most studies are stil in experimental step. For the clinical application of nerve tissue engineering, some problems to be solved include:(1) source and ethics of seed cells;(2) immunological rejection fol owing cellproliferation and transplantation;(3) stability and oncogenicity of transplanted cells;(4) degradation rate, optimal porosity, tube thickness and shape;(5) repair timing for in vitro tissue-engineered nerve construction;(6) local release and regulation of various neurobiological factors. With the development of science, many patients with nerve injuries can profit from the solve of these problems.%背景:近年来,随着生物工程技术以及组织工程化神经的发展给周围神经缺损的治疗带来了新的希望,已逐渐成为研究的焦点。目的:从种子细胞、生物材料以及构建周围神经组织技术3个方面综述组织工程方法修复周围神经损伤的新进展。方法:由第一作者在2013年7

  5. Study on the utilization of the energy produced by the exhaust gases and the cooling water of a internal combustion engine; Estudo do aproveitamento da energia obtida pelos gases de escapamento e pela agua de resfriamento de um motor de combustao interna

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Andre Luiz dos; Arroyo, Narciso Angel Ramos [Santa Catarina Univ., Florianopolis (Brazil). Dept. de Engenharia Mecanica. Lab. de Combustao e Motores Termicos]. E-mail: als2000@tutopia.com.br; arroyo@sinmec.ufsc.br

    2000-07-01

    This work is about heat balance of an automotive internal combustion engine of 4 cylinders, using ethylic alcohol, and utilize the energy obtained in the exhaust gas and the water cooling system. This paper show an theoretical - experimental model for use this energy in an absorption refrigeration system using the work fluid water and Li Br. In this paper are analyzed engines charges of 30%, 50% and 100%. The results shows that for this charges and for any speed of the engines, the energy obtained in the evaporator are significant. (author)

  6. The 23rd Annual Meeting of the European Tissue Repair Society (ETRS) in Reims, France

    NARCIS (Netherlands)

    Hoff, J.W. Von den; Agren, M.S.; Coulomb, B.; Eming, S.A.; Lataillade, J.J.

    2014-01-01

    The 23rd Annual Meeting of the European Tissue Repair Society, Reims, France, October 23 to 25, 2013 focused on tissue repair and regenerative medicine covering topics such as stem cells, biomaterials, tissue engineering, and burns.

  7. Statistics Analysis Measures Painting of Cooling Tower

    Directory of Open Access Journals (Sweden)

    A. Zacharopoulou

    2013-01-01

    Full Text Available This study refers to the cooling tower of Megalopolis (construction 1975 and protection from corrosive environment. The maintenance of the cooling tower took place in 2008. The cooling tower was badly damaged from corrosion of reinforcement. The parabolic cooling towers (factory of electrical power are a typical example of construction, which has a special aggressive environment. The protection of cooling towers is usually achieved through organic coatings. Because of the different environmental impacts on the internal and external side of the cooling tower, a different system of paint application is required. The present study refers to the damages caused by corrosion process. The corrosive environments, the application of this painting, the quality control process, the measures and statistics analysis, and the results were discussed in this study. In the process of quality control the following measurements were taken into consideration: (1 examination of the adhesion with the cross-cut test, (2 examination of the film thickness, and (3 controlling of the pull-off resistance for concrete substrates and paintings. Finally, this study refers to the correlations of measurements, analysis of failures in relation to the quality of repair, and rehabilitation of the cooling tower. Also this study made a first attempt to apply the specific corrosion inhibitors in such a large structure.

  8. Transfect bone marrow stromal cells with pcDNA3.1-VEGF to construct tissue engineered bone in defect repair

    Institute of Scientific and Technical Information of China (English)

    SI Hai-peng; ZHANG Xi-hua; LU Zhi-hua; LIN Yong-liang; LI Jing-jing; YIN Qing-feng; ZHAO Dong-mei; WANG Shao-jin; LI Jian-min; WANG Hai-bin

    2012-01-01

    Background We previously showed that nano-hydroxyapatite/carboxymethyl chitosan (n-Ha/CMCS) displayed excellent mechanical properties,good degradation rates and exceptional biocompatibility,with negligible toxicity.The aim of this study was to determine the effect of the same composite with vascular endothelial growth factor (VEGF)-transfected bone marrow stromal cells (BMSCs) in a rabbit radial defect model.Methods The nano-hydroxyapatite was produced through co-precipitation.The n-HA/CMCS scaffold was produced by particle filtration and lyophilization followed by genipin crosslinking.Total RNA from rabbit bone was reverse-transcribed to synthesize VEGF165-pcDNA3.1 that was transfected into the BMSCs.The composite was implanted into a rabbit radial defect model,and the osteogenic activity examined by gross morphology,X-ray examination and hematoxylin and eosin (HE) staining.Results The microstructure and mechanical property of the n-HNCMCS scaffold resembled natural cancellous bone.Compared with glutaric dialdehyde crosslinked scaffolds,the genipin crosslinked scaffold was less toxic,and displayed a higher capacity to promote cell adhesion and proliferation.Spontaneous fluorescence of the composite permitted visualization of the composite-bone interface and the adhesion behavior of cells on the scaffold under laser scanning confocal microscopy.The scaffold with VEGF-transfected BMSCs bridged the bony defect and promoted healing,with most of the implanted material being replaced by natural bone over time with little residual implant.Using X-ray,we noted obvious callus formation and recanalization of the bone marrow cavity.Furthermore,HE stained sections showed new cortical bone formation.Conclusions The n-HA/CMCS scaffold composite with VEGF-trasnfected BMSCs is biocompatible,nontoxic,promotes the infiltration and formation of the microcirculation,and stimulates bone defect repair.Furthermore,the degradation rate of the composite matched that of growing bone

  9. Systems Maintenance Automated Repair Tasks (SMART)

    Science.gov (United States)

    Schuh, Joseph; Mitchell, Brent; Locklear, Louis; Belson, Martin A.; Al-Shihabi, Mary Jo Y.; King, Nadean; Norena, Elkin; Hardin, Derek

    2010-01-01

    SMART is a uniform automated discrepancy analysis and repair-authoring platform that improves technical accuracy and timely delivery of repair procedures for a given discrepancy (see figure a). SMART will minimize data errors, create uniform repair processes, and enhance the existing knowledge base of engineering repair processes. This innovation is the first tool developed that links the hardware specification requirements with the actual repair methods, sequences, and required equipment. SMART is flexibly designed to be useable by multiple engineering groups requiring decision analysis, and by any work authorization and disposition platform (see figure b). The organizational logic creates the link between specification requirements of the hardware, and specific procedures required to repair discrepancies. The first segment in the SMART process uses a decision analysis tree to define all the permutations between component/ subcomponent/discrepancy/repair on the hardware. The second segment uses a repair matrix to define what the steps and sequences are for any repair defined in the decision tree. This segment also allows for the selection of specific steps from multivariable steps. SMART will also be able to interface with outside databases and to store information from them to be inserted into the repair-procedure document. Some of the steps will be identified as optional, and would only be used based on the location and the current configuration of the hardware. The output from this analysis would be sent to a work authoring system in the form of a predefined sequence of steps containing required actions, tools, parts, materials, certifications, and specific requirements controlling quality, functional requirements, and limitations.

  10. The 23rd Annual Meeting of the European Tissue Repair Society (ETRS) in Reims, France

    DEFF Research Database (Denmark)

    Von den Hoff, Johannes W; Ågren, Sven Per Magnus; Coulomb, Bernard;

    2014-01-01

    The 23rd Annual Meeting of the European Tissue Repair Society, Reims, France, October 23 to 25, 2013 focused on tissue repair and regenerative medicine covering topics such as stem cells, biomaterials, tissue engineering, and burns.......The 23rd Annual Meeting of the European Tissue Repair Society, Reims, France, October 23 to 25, 2013 focused on tissue repair and regenerative medicine covering topics such as stem cells, biomaterials, tissue engineering, and burns....

  11. Method of repairing discontinuity in fiberglass structures

    Science.gov (United States)

    Gelb, L. L.; Helbert, W. B., Jr.; Enie, R. B.; Mulliken, R. F. (Inventor)

    1974-01-01

    Damaged fiberglass structures are repaired by substantially filling the irregular surfaced damaged area with a liquid, self-curing resin, preferably an epoxy resin mixed with chopped fiberglass, and then applying to the resin surface the first of several woven fiberglass swatches which has stitching in a zig-zag pattern parallel to each of its edges and a fringe of warp and fill glass fibers about the edges outward of the stitching. The method is especially applicable to repair of fiberglass rocket engine casings and is particularly advantageous since it restores the repaired fiberglass structure to substantially its original strength without any significant changes in the geometry or mass of the structure.

  12. Hybrid radiator cooling system

    Science.gov (United States)

    France, David M.; Smith, David S.; Yu, Wenhua; Routbort, Jules L.

    2016-03-15

    A method and hybrid radiator-cooling apparatus for implementing enhanced radiator-cooling are provided. The hybrid radiator-cooling apparatus includes an air-side finned surface for air cooling; an elongated vertically extending surface extending outwardly from the air-side finned surface on a downstream air-side of the hybrid radiator; and a water supply for selectively providing evaporative cooling with water flow by gravity on the elongated vertically extending surface.

  13. Recent Development in Turbine Blade Film Cooling

    Directory of Open Access Journals (Sweden)

    Je-Chin Han

    2001-01-01

    Full Text Available Gas turbines are extensively used for aircraft propulsion, land-based power generation, and industrial applications. Thermal efficiency and power output of gas turbines increase with increasing turbine rotor inlet temperature (RIT. The current RIT level in advanced gas turbines is far above the .melting point of the blade material. Therefore, along with high temperature material development, a sophisticated cooling scheme must be developed for continuous safe operation of gas turbines with high performance. Gas turbine blades are cooled internally and externally. This paper focuses on external blade cooling or so-called film cooling. In film cooling, relatively cool air is injected from the inside of the blade to the outside surface which forms a protective layer between the blade surface and hot gas streams. Performance of film cooling primarily depends on the coolant to mainstream pressure ratio, temperature ratio, and film hole location and geometry under representative engine flow conditions. In the past number of years there has been considerable progress in turbine film cooling research and this paper is limited to review a few selected publications to reflect recent development in turbine blade film cooling.

  14. DNA repair. [UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Setlow, R.

    1978-01-01

    Some topics discussed are as follows: difficulty in extrapolating data from E. coli to mammalian systems; mutations caused by UV-induced changes in DNA; mutants deficient in excision repair; other postreplication mechanisms; kinds of excision repair systems; detection of repair by biochemical or biophysical means; human mutants deficient in repair; mutagenic effects of UV on XP cells; and detection of UV-repair defects among XP individuals. (HLW)

  15. Repair of overheating linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Barkley, Walter; Baldwin, William; Bennett, Gloria; Bitteker, Leo; Borden, Michael; Casados, Jeff; Fitzgerald, Daniel; Gorman, Fred; Johnson, Kenneth; Kurennoy, Sergey; Martinez, Alberto; O’Hara, James; Perez, Edward; Roller, Brandon; Rybarcyk, Lawrence; Stark, Peter; Stockton, Jerry

    2004-01-01

    Los Alamos Neutron Science Center (LANSCE) is a proton accelerator that produces high energy particle beams for experiments. These beams include neutrons and protons for diverse uses including radiography, isotope production, small feature study, lattice vibrations and material science. The Drift Tube Linear Accelerator (DTL) is the first portion of a half mile long linear section of accelerator that raises the beam energy from 750 keV to 100 MeV. In its 31st year of operation (2003), the DTL experienced serious issues. The first problem was the inability to maintain resonant frequency at full power. The second problem was increased occurrences of over-temperature failure of cooling hoses. These shortcomings led to an investigation during the 2003 yearly preventative maintenance shutdown that showed evidence of excessive heating: discolored interior tank walls and coper oxide deposition in the cooling circuits. Since overheating was suspected to be caused by compromised heat transfer, improving that was the focus of the repair effort. Investigations revealed copper oxide flow inhibition and iron oxide scale build up. Acid cleaning was implemented with careful attention to protection of the base metal, selection of components to clean and minimization of exposure times. The effort has been very successful in bringing the accelerator through a complete eight month run cycle allowing an incredible array of scientific experiments to be completed this year (2003-2004). This paper will describe the systems, investigation analysis, repair, return to production and conclusion.

  16. Computational investigation of film cooling from cylindrical and row trenched cooling holes near the combustor endwall

    Directory of Open Access Journals (Sweden)

    Ehsan Kianpour

    2014-11-01

    Full Text Available This study was performed to investigate the effects of cylindrical and row trenched cooling holes with alignment angles of 0° and 90° at blowing ratio of 3.18 on the film cooling performance adjacent to the endwall surface of a combustor simulator. In this research a three-dimensional representation of Pratt and Whitney gas turbine engine was simulated and analyzed with a commercial finite volume package FLUENT 6.2. The analysis has been carried out with Reynolds-Averaged Navier–Stokes turbulence model (RANS on internal cooling passages. This combustor simulator was combined with the interaction of two rows of dilution jets, which were staggered in the streamwise direction and aligned in the spanwise direction. Film cooling was placed along the combustor liner walls. In comparison with the baseline case of cooling holes, the application of a row trenched hole near the endwall surface doubled the performance of film cooling effectiveness.

  17. Journal of Tissue Engineering and Reconstructive Surgery%The Clinical Comparison Study of Two Different Methods for Repairing Facial Soft Tissue Defect in Severe Progressive Facial Hemiatrophy

    Institute of Scientific and Technical Information of China (English)

    陈军宝; 李澍源; 曹谊林; 李秉航; 滕利; 卢建建; 徐家杰; 张超; 解芳; 杨莉亚; 杨璐

    2016-01-01

    Objective To evaluate clinical effect of free anterolateral thigh adipofascial flap transplantation and autologous fat graft to repair facial soft tissue defection in severe progressive facial hemiatrophy. Methods From September 2013 to December 2015, 16 patients with progressive facial hemiatrophy were selected according to enter criterion. The patients were divided into two groups according to different surgical methods, autologous fat graft group (Group A, n=8) and free anterolateral thigh adipofascial flap group (Group B, n=8). The facial three-dimensional data were acquired via 3-D scanner preoperatively. Using Mimics 17.0 and Geomagic studio 12.0 software, facial 3-D model of patient was reconstructed, facial symmetry was analyzed, the volume of facial tissue defect was calculated and the reconstruction scope of facial soft tissue was designed. All the patients were operated and clinical indexes were analysed after 6 months. Results The facial symmetry and soft tissue defect in Group A and Group B 6 months post-operation were both significantly improved compared with pre-operation (P0.05). The patients′clinical indexes: total operation time, postoperative hospital stay in Group B were greater than in Group A, times of hospitalization of Group B surpassed Group A with statistical significance (P0.05). Satisfaction score: patients postoperative satisfaction in Group A was better than in Group B (P0.05). Conclusion The clinical effect of autologous fat graft in repairing facial soft tissue defect of severe PFHA patients is non-inferior to free anterolateral thigh adipofascial flap transplantation with good clinical effects and high satisfactory, and is worthy of clinical application.%目的:比较吻合血管的股前外侧筋膜脂肪瓣移植与自体脂肪移植两种方法,修复重度半侧颜面萎缩(PFHA)患者面部软组织缺损的临床效果。方法自2013年09月至2015年12月,根据入组标准选取PFHA患者16例,分为自

  18. Optimal Strategy for Inspection and Repair of Structural Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Sørensen, John Dalsgaard

    1987-01-01

    A new strategy for inspection and repair of structural elements and systems is presented. The total cost of inspection and repair is minimized with the constraints that the reliability of elements and/or of the structural system are acceptable. The design variables are the time intervals between...... inspections and the quality of the inspections. Numerical examples are presented to illustrate the performance of the strategy. The strategy can be used for any engineering system where inspection and repair are required....

  19. Direct Liquid Cooling for Electronic Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Coles, Henry; Greenberg, Steve

    2014-03-01

    This report documents a demonstration of an electronic--equipment cooling system in the engineering prototype development stage that can be applied in data centers. The technology provides cooling by bringing a water--based cooling fluid into direct contact with high--heat--generating electronic components. This direct cooling system improves overall data center energy efficiency in three ways: High--heat--generating electronic components are more efficiently cooled directly using water, capturing a large portion of the total electronic equipment heat generated. This captured heat reduces the load on the less--efficient air--based data center room cooling systems. The combination contributes to the overall savings. The power consumption of the electronic equipment internal fans is significantly reduced when equipped with this cooling system. The temperature of the cooling water supplied to the direct cooling system can be much higher than that commonly provided by facility chilled water loops, and therefore can be produced with lower cooling infrastructure energy consumption and possibly compressor-free cooling. Providing opportunities for heat reuse is an additional benefit of this technology. The cooling system can be controlled to produce high return water temperatures while providing adequate component cooling. The demonstration was conducted in a data center located at Lawrence Berkeley National Laboratory in Berkeley, California. Thirty--eight servers equipped with the liquid cooling system and instrumented for energy measurements were placed in a single rack. Two unmodified servers of the same configuration, located in an adjacent rack, were used to provide a baseline. The demonstration characterized the fraction of heat removed by the direct cooling technology, quantified the energy savings for a number of cooling infrastructure scenarios, and provided information that could be used to investigate heat reuse opportunities. Thermal measurement data were used

  20. Numerical investigations of thermal stratification in cooling channel of liquid rocket engine thrust chamber%液体火箭发动机推力室冷却通道温度分层数值研究

    Institute of Scientific and Technical Information of China (English)

    康玉东; 孙冰; 高翔宇

    2009-01-01

    为了研究冷却剂温度分层的形成机理及其对流动和换热的影响,应用雷诺应力模型(RSM)对液体火箭发动机推力室再生冷却通道的流动与传热进行了三维数值模拟,冷却剂为气氢,考虑其物性随温度和压力的变化.所得结果表明:冷却剂在非流动方向会出现温度分层现象,随着冷却剂的不断受热,温度分层现象越明显,由于喉部二次流加强了冷却剂间的混合,在喉部区域温度分层被减弱,温度分层对冷却剂温升及压降影响较小,严重影响气壁温度的估算.%To study the formation mechanism of thermal stratification in cooling channel and its effects on the flow and heat transfer,three dimensional turbulent fluid flow and heat transfer in a regenerative-cooling channel of liquid rocket engine were numerically investigated with Reynolds stress model(RSM) model,and the coolant was hydrogen,whose thermo-physical properties varied with both temperature and pressure.The results show that thermal stratification occurs at non-flow direction,the extent of thermal stratification becomes increasingly significant as the extent of heating increases,and the thermal stratification of coolant is weakened for the existence of secondary flow in throat region; the thermal stratification has little effect on the bulk temperature increase and hydrodynamic losses of hydrogen,but has significant effect on the calculation of the wall heat fluxes and temperature.

  1. 基于微机系统的高温气冷堆工程仿真机%A Personal Computer-Based Engineering Simulator for High Temperature Gas-Cooled Reactor

    Institute of Scientific and Technical Information of China (English)

    石磊; 高祖瑛

    2001-01-01

    A personal computer(PC)-based engineering simulator for high temperature gas-cooled reactor(HTR), HTRSIMU has been developed by Institute of Nuclear Energy Technology(INET) of Tsinghua University. HTRSIMU runs on Windows 98 or Windows 2000 operating system, in which the multi-process and multi-monitor techniques are applied.The graphical user interface is friendly and easy to operate.The basic models include the reactor core, the main loop system and steam generator of 10MW high temperature gas-cooled reactor(HTR-10), which can be simulated detailed in normal operation and transient accidents.The simulation results are in good agreement with design data and the safety analysis reports of HTR-10.HTRSIMU can be used as an education al tool to understand the design and operational characteristics of a HTR. In the future, HTRSIMU will provide on -line supports for operators in the main control room of HTR-10%基于微机系统的高温气冷堆工程仿真机 (HTRSIMU)由清华大学核能技术设计研究院开发完成。 HTRSIMU运行于 Windows98或 Windows2000平台上,采用多进程、多显示器结构,具有人机界面友好、结构紧凑、操作方便、易于扩展等特点。它的模型包括 10MW高温气冷堆 (HTR-10)的一、二回路主要部件,能够对反应堆堆芯、主回路系统和蒸汽发生器等部件做详细的物理和热工分析计算,可以模拟正常运行和各种事故工况过程,仿真结果与 HTR-10的设计值和安全分析报告符合得很好。利用 HTRSIMU系统不仅可以进行高温气冷堆的工程设计、安全分析和人员培训,而且将来可以对 HTR-10主控室的操纵人员进行现场支持,给实际运行和各项研究提供帮助。

  2. Application of tissue-engineered anterior cruciate ligament in repair of exercise injury%组织工程化前交叉韧带在运动损伤修复中应用

    Institute of Scientific and Technical Information of China (English)

    施海平

    2011-01-01

    -related anterior cruciate ligament is extremely poor, so it isextremely difficult for athletes to recover. In recent years, research on tissue-engineered anterior cruci ate ligament has made rapidprogress with prospect and extensive application. But with regard to application, the optimal clinical outcomes of anterior cruciateligament repair and reconstruction can only be achieved by organically blending the selection of tissue-engineered seed cells, theconstruction of scaffold materials with the basic research on tissue-engineered anterior cruciate ligament, as well as using growthfactor properly.

  3. Liquid-Cooled Garment

    Science.gov (United States)

    1977-01-01

    A liquid-cooled bra, offshoot of Apollo moon suit technology, aids the cancer-detection technique known as infrared thermography. Water flowing through tubes in the bra cools the skin surface to improve resolution of thermograph image.

  4. Progress in patch repair of aerospace composite structures

    Science.gov (United States)

    Hou, Weiguo; Zhang, Weifang; Tang, Qingyun

    2012-04-01

    With the rapid application of the composite structure in the aerospace industry, more load-bearing structures and components are used with composites instead of conventional engineering materials. However, the composite structures are inevitably suffered damages in the complex environment, the composites structures repair become more important in the airplane maintenance. This paper describes the composites patch repair progress. Firstly, the flaws and damages concerned to composite structures are concluded, and also the repair principles are presented. Secondly, the advantages and disadvantages for different repair methods are analyzed, as well as the different bonded repair and their applicability to different structures is discussed. According the recent research in theory and experiment, the scarf repair effects under different parameters are analyzed. Finally, the failure mechanisms of repair structure are discussed, and some prospects are put forward.

  5. Hypersonic aerospace vehicle leading edge cooling using heat pipe, transpiration and film cooling techniques

    Science.gov (United States)

    Modlin, James Michael

    An investigation was conducted to study the feasibility of cooling hypersonic vehicle leading edge structures exposed to severe aerodynamic surface heat fluxes using a combination of liquid metal heat pipes and surface mass transfer cooling techniques. A generalized, transient, finite difference based hypersonic leading edge cooling model was developed that incorporated these effects and was demonstrated on an assumed aerospace plane-type wing leading edge section and a SCRAMJET engine inlet leading edge section. The hypersonic leading edge cooling model was developed using an existing, experimentally verified heat pipe model. Two applications of the hypersonic leading edge cooling model were examined. An assumed aerospace plane-type wing leading edge section exposed to a severe laminar, hypersonic aerodynamic surface heat flux was studied. A second application of the hypersonic leading edge cooling model was conducted on an assumed one-quarter inch nose diameter SCRAMJET engine inlet leading edge section exposed to both a transient laminar, hypersonic aerodynamic surface heat flux and a type 4 shock interference surface heat flux. The investigation led to the conclusion that cooling leading edge structures exposed to severe hypersonic flight environments using a combination of liquid metal heat pipe, surface transpiration, and film cooling methods appeared feasible.

  6. 40 CFR 86.1335-90 - Cool-down procedure.

    Science.gov (United States)

    2010-07-01

    ... °C), shall be shut off. No engine oil change is permitted during the test sequence. (2) Direct cooling of engine oil through the use of oil coolers or heat exchangers is permitted. The cold cycle... in contact with any engine surface. (ii) The flow of oil and water shall be shut off during...

  7. Data center cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Chainer, Timothy J; Dang, Hien P; Parida, Pritish R; Schultz, Mark D; Sharma, Arun

    2015-03-17

    A data center cooling system may include heat transfer equipment to cool a liquid coolant without vapor compression refrigeration, and the liquid coolant is used on a liquid cooled information technology equipment rack housed in the data center. The system may also include a controller-apparatus to regulate the liquid coolant flow to the liquid cooled information technology equipment rack through a range of liquid coolant flow values based upon information technology equipment temperature thresholds.

  8. Stochastic cooling in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Brennan,J.M.; Blaskiewicz, M. M.; Severino, F.

    2009-05-04

    After the success of longitudinal stochastic cooling of bunched heavy ion beam in RHIC, transverse stochastic cooling in the vertical plane of Yellow ring was installed and is being commissioned with proton beam. This report presents the status of the effort and gives an estimate, based on simulation, of the RHIC luminosity with stochastic cooling in all planes.

  9. Diesel engines in practice. 8. rev. ed. Dieselmotoren-Praxis

    Energy Technology Data Exchange (ETDEWEB)

    Baentsch, E.

    1987-01-01

    The well-known manual has been completely revised and re-edited. A brief historical and economic review is followed by a discussion of the following subjects: Torque and power; fuel consumption; lube oil and cooling water; mass balance in multicylinder engines; oversquare and undersquare engines; suction engines and supercharged engines; two-stroke and four-stroke engines; engine selection; combustion processes; exhaust emissions; diesel engines in operation; cooling; piping; lubrication; starting; practical tests; variable-fuel engines. (HWJ).

  10. Diesel Engine Technician

    Science.gov (United States)

    Tech Directions, 2010

    2010-01-01

    Diesel engine technicians maintain and repair the engines that power transportation equipment such as heavy trucks, trains, buses, and locomotives. Some technicians work mainly on farm machines, ships, compressors, and pumps. Others work mostly on construction equipment such as cranes, power shovels, bulldozers, and paving machines. This article…

  11. Pectus excavatum repair

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002949.htm Pectus excavatum repair To use the sharing features on this page, please enable JavaScript. Pectus excavatum repair is surgery to correct pectus excavatum . This ...

  12. Laser cooling of solids

    OpenAIRE

    Nemova, Galina

    2009-01-01

    Parallel to advances in laser cooling of atoms and ions in dilute gas phase, which has progressed immensely, resulting in physics Nobel prizes in 1997 and 2001, major progress has recently been made in laser cooling of solids. I compare the physical nature of the laser cooling of atoms and ions with that of the laser cooling of solids. I point out all advantages of this new and very promising area of laser physics. Laser cooling of solids (optical refrigeration) at the present time can be lar...

  13. Central cooling: absorptive chillers

    Energy Technology Data Exchange (ETDEWEB)

    Christian, J.E.

    1977-08-01

    This technology evaluation covers commercially available single-effect, lithium-bromide absorption chillers ranging in nominal cooling capacities of 3 to 1,660 tons and double-effect lithium-bromide chillers from 385 to 1,060 tons. The nominal COP measured at operating conditions of 12 psig input steam for the single-effect machine, 85/sup 0/ entering condenser water, and 44/sup 0/F exiting chilled-water, ranges from 0.6 to 0.65. The nominal COP for the double-effect machine varies from 1.0 to 1.15 with 144 psig entering steam. Data are provided to estimate absorption-chiller performance at off-nominal operating conditions. The part-load performance curves along with cost estimating functions help the system design engineer select absorption equipment for a particular application based on life-cycle costs. Several suggestions are offered which may be useful for interfacing an absorption chiller with the remaining Integrated Community Energy System. The ammonia-water absorption chillers are not considered to be readily available technology for ICES application; therefore, performance and cost data on them are not included in this evaluation.

  14. Tissue engineering technology and biomaterials for repair of sports articular cartilage injury%组织工程技术及生物材料修复运动性关节软骨损伤

    Institute of Scientific and Technical Information of China (English)

    马金玉; 薛媛; 杨洪武

    2011-01-01

    January 1993 to October 2010 was performed for related articles, using "articular cartilage, tissue engineering technology, biomaterials" for the Chinese key words and "tissue engineering, articular cartilage, scaffold material" for the English key words, duplicated research or Meta analysis were eliminated. Twenty-three papers mainly discuss seed cells,scaffolds, cytokines and their properties in the repair of sports articular cartilage injury.RESULTS : Totally 104 studies were screened out by computer search, according to inclusion and exclusion criteria, studies regarding the seed cells and bio-scaffolds for cartilage tissue engineering, as well as cytokines for tissue engineering were summarized and analyzed. Seed cells are the primary factor restricting clinical application of tissue engineered cartilage, the common seed cells include cartilage cells, bone marrow stromal stem cells and embryonic stem cells; bio-scaffold materials includes natural materials and synthetic biodegradable polymers; the growth factors for cartilage tissue engineering include transforming growth factor, bone morphogenetic protein, fibroblast growth factor, insulin-like growth factor and so on.CONCLUSION: So far, there is no ideal materials for the seed cells and scaffold materials of engineered cartilage, as well as culture environment, the focus of future research is a kind of tissue engineered articular cartilage with good performance.However, many studies are still in the experimental stage, and some problems need to be solved, especially after tissue engineering scaffolds are implanted, whether the material degradation is synchronized with cell functioning, thus altering genetic materials, gene expression or gene mutation, their clinical application requires relevant scholars and experts to constantly practice and explore.

  15. 组织工程化韧带在前交叉韧带运动损伤修复中的作用%Tissue engineered ligament in repair of sports-induced anterior cruciate ligament injury

    Institute of Scientific and Technical Information of China (English)

    许荣梅

    2011-01-01

    背景:交叉韧带是膝关节内的核心性稳定结构,具有制导膝关节生理活动并限制非生理性活动的功能,其中前交叉韧带的作用更为重要,其损伤的治疗已成为目前运动医学研究的热点.目的:探讨前交叉韧带生理功能、损伤机制,综述其修复过程中组织工程化材料的研究成果.方法:应用计算机检索1990-01/2011-02 PubMed数据库及维普数据库有关前交叉韧带组织工程研究进展、肌腱支架材料生物力学分析、生物材料在肌腱组织工程中应用及组织工程技术在修复肌腱缺损临床应用方面的相关文献,英文检索词"anterior cruciate ligament,biological materials,damage,treatment",中文检索词"前交叉韧带,生物材料,损伤,治疗",检索文献量总计102篇.结果与结论:前交叉韧带损伤后组织工程化康复措施得到了较快发展,从材料的选择来看,单一移植材料难免会存在诸多不足,不利于韧带的康复,复合材料可以结合不同材料的特性对韧带组织工程化材料进行配置,可以弥补单一材料的生物相容性、降解速度、生物力学性能、材料的韧性等不足,另外,对组织工程化材料进行功能结构加工也是尤为重要,这样可以更大程度的为细胞提供吸附、成长和分化的良好环境.同时,基因技术的进步以及各种新型材料的研制,必将在更大程度上满足前交叉韧带康复的需要.%BACKGROUND: Cruciate ligaments are the core of the knee joint, which can guide physical activity and limit non-physiological functions of the joint. The anterior cruciate ligament is especially important, and anterior cruciate ligament injury has become the hotspot in sports medicine.OBJECTIVE: To investigate the achievements on the physiological functions, injury mechanism and tissue-engineered materials used in the repair of anterior cruciate ligament.MEHTODS: A computer-based search was conducted in PubMed and VIP databases for

  16. When "Other" Initiate Repair.

    Science.gov (United States)

    Schegloff, Emanuel A.

    2000-01-01

    Elaborates on the locus of other-initiated repair, and reports on a number of environments in which others initiate repair turns later than the one directly following the trouble-source turn. Describes several ways that other initiation of repair, which occurs in next-turn position, may be delayed within that position. (Author/VWL)

  17. Assessment of spent fuel cooling

    Energy Technology Data Exchange (ETDEWEB)

    Ibarra, J.G.; Jones, W.R.; Lanik, G.F. [and others

    1997-02-01

    The paper presents the methodology, the findings, and the conclusions of a study that was done by the Nuclear Regulatory Commission`s Office for Analysis and Evaluation of Operational Data (AEOD) on loss of spent fuel pool cooling. The study involved an examination of spent fuel pool designs, operating experience, operating practices, and procedures. AEOD`s work was augmented in the area of statistics and probabilistic risk assessment by experts from the Idaho Nuclear Engineering Laboratory. Operating experience was integrated into a probabilistic risk assessment to gain insight on the risks from spent fuel pools.

  18. Biofouling Control in Cooling Water

    Directory of Open Access Journals (Sweden)

    T. Reg Bott

    2009-01-01

    Full Text Available An important aspect of environmental engineering is the control of greenhouse gas emissions. Fossil fuel-fired power stations, for instance, represent a substantial contribution to this problem. Unless suitable steps are taken the accumulation of microbial deposits (biofouling on the cooling water side of the steam condensers can reduce their efficiency and in consequence, the overall efficiency of power production, with an attendant increase in fuel consumption and hence CO2 production. Biofouling control, therefore, is extremely important and can be exercised by chemical or physical techniques or a combination of both. The paper gives some examples of the effectiveness of different approaches to biofouling control.

  19. 组织工程化骨修复兔桡骨缺损的实验研究%Repair of radius defection by tissure engineering bone in rabbits

    Institute of Scientific and Technical Information of China (English)

    高欣凤; 胡炜; 崔子健; 孙天威

    2012-01-01

    Objective: To discuss the repair of rabbits radius defection by using bone marrow stromal stem cells (MSCs)in conjunction with bone morphogenetic protein(BMP) and freeze-dried demineralized bone matrix(FDBM) as scaffold. Methods: MSCs were separated and cultivate in vitro, with FDBM as scaffold, osteogenesis was induced by BMP. Forty-five Japan white rabbits were randomly divided into three groups, Group A was MSCs+FDBM+BMP,Group B was FDBM+BMP, Group C was blank control group. The repairing of 15mm defection of rabbit radius was processed. Rabbits were killed at 12 weeks after operation. The general observation and imageology were used to assess the repairing condition. The implantation was estimated by using histology and tissue biomechanics methods. Results: The animals were executed at 12 weeks after operation, with general observation, the fusion mass character in group A was hard, the morphology was not regulation. Some bony callus can be seen in group B, and the defection was not repaired. Granulation tissue was filled in the radius defection, and any bony callus could not be seen. Histology observation of Masson staining showed there were large number of cartilage and newly bom bone trabecular formation processed in bone active period near junction place in group A. Less newly born bone trabecular formation could be seen in group B and the FDBM bone trabecular was tapering , less and cracked. No newly born bone trabecular was seen in group C. Tissue biomechanics measurement: Maximum load, Compressive strength, Modulus of elasticity were( 87.8± 9.8)N,(8.4±0.9)MPa and( 187.5+8.2)GPa in group A, less than the healthy side [(112.3±11.2)N,(9.5±0.2)MPa(210.5±15.9)GPa], P<0.05. Conclusion: Repairing bone defect with tissue engineering bone is superior to using FDBM combine with BMP.Early stage biomechanic intensity is inferior to normal bone tissure.%目的:探讨骨髓间充质干细胞复合脱钙骨基质和骨形成蛋白修复兔桡骨缺损的效果.

  20. Cooling systems for ultra-high temperature turbines.

    Science.gov (United States)

    Yoshida, T

    2001-05-01

    This paper describes an introduction of research and development activities on steam cooling in gas turbines at elevated temperature of 1500 C and 1700 C level, partially including those on water cooling. Descriptions of a new cooling system that employs heat pipes are also made. From the view point of heat transfer, its promising applicability is shown with experimental data and engine performance numerical evaluation.

  1. Prototype solar heating and combined heating cooling systems

    Science.gov (United States)

    1978-01-01

    The design and development of eight prototype solar heating and combined heating and cooling systems is discussed. The program management and systems engineering are reported, and operational test sites are identified.

  2. Heat and mass transfer problems for film cooling

    Energy Technology Data Exchange (ETDEWEB)

    Leontiev, A.I.

    1999-07-01

    An advance in many branches of engineering is connected with using of more and more high working temperatures, perfection of cooling systems of power installations and further development of the theory of heat transfer. One of the most promising methods of thermal protection of heating surfaces is using of the gas film cooling. Despite intensive development of numerical methods of calculation of film cooling problems, simple and reliable correlations, which are based on clear physical models, that make it possible to generalize experimental data for complex boundary conditions, are necessary for complex engineering calculations. It is well known, that an increase in an initial gas temperature of the gas at the turbine inlet is the basic method to advance technical and economical parameters of the gas turbine units and engines. Modern gas turbine engines are designed to operate at inlet temperatures of 1,800--2,000 K, which are far above the allowable temperatures of the metal. Under these conditions, the turbine blades should be cooled in order to ensure a reasonable lifetime. In the paper the review of calculation methods and of experimental results on heat transfer under film cooling is presented. The effect of an arrangement of film cooling, longitudinal gradient of pressure, nonisothermality and compressibility of gas, swirling of flow, and turbulent pulsations of the main gas flow on effectiveness of the gas film cooling is considered. A method of calculation of combined cooling (film, porous or transpiration and convective) is proposed.

  3. 46 CFR 111.59-3 - No mechanical cooling.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false No mechanical cooling. 111.59-3 Section 111.59-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Busways § 111.59-3 No mechanical cooling. A busway must not need mechanical...

  4. Stochastic cooling in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Brennan J. M.; Blaskiewicz, M.; Mernick, K.

    2012-05-20

    The full 6-dimensional [x,x'; y,y'; z,z'] stochastic cooling system for RHIC was completed and operational for the FY12 Uranium-Uranium collider run. Cooling enhances the integrated luminosity of the Uranium collisions by a factor of 5, primarily by reducing the transverse emittances but also by cooling in the longitudinal plane to preserve the bunch length. The components have been deployed incrementally over the past several runs, beginning with longitudinal cooling, then cooling in the vertical planes but multiplexed between the Yellow and Blue rings, next cooling both rings simultaneously in vertical (the horizontal plane was cooled by betatron coupling), and now simultaneous horizontal cooling has been commissioned. The system operated between 5 and 9 GHz and with 3 x 10{sup 8} Uranium ions per bunch and produces a cooling half-time of approximately 20 minutes. The ultimate emittance is determined by the balance between cooling and emittance growth from Intra-Beam Scattering. Specific details of the apparatus and mathematical techniques for calculating its performance have been published elsewhere. Here we report on: the method of operation, results with beam, and comparison of results to simulations.

  5. Percutaneous mitral valve repair.

    Science.gov (United States)

    Gillinov, A Marc; Liddicoat, John R

    2006-01-01

    Surgical mitral valve repair is the procedure of choice to treat mitral regurgitation of all etiologies. Whereas annuloplasty is the cornerstone of mitral valve repair, a variety of other surgical techniques are utilized to correct dysfunction of the leaflets and subvalvular apparatus; in most cases, surgical repair entails application of multiple repair techniques in each patient. Preclinical studies and early human experience have demonstrated that some of these surgical repair techniques can be performed using percutaneous approaches. Specifically, there has been great progress in the development of novel technology to facilitate percutaneous annuloplasty and percutaneous edge-to-edge repair. The objectives of this report were to (1) discuss the surgical foundations for these percutaneous approaches; (2) review device design and experimental and clinical results of percutaneous valve repair; and (3) address future directions, including the key challenges of patient selection and clinical trial design.

  6. Cooling by Thermodynamic Induction

    Science.gov (United States)

    Patitsas, S. N.

    2017-03-01

    A method is described for cooling conductive channels to below ambient temperature. The thermodynamic induction principle dictates that the electrically biased channel will cool if the electrical conductance decreases with temperature. The extent of this cooling is calculated in detail for both cases of ballistic and conventional transport with specific calculations for carbon nanotubes and conventional metals, followed by discussions for semiconductors, graphene, and metal-insulator transition systems. A theorem is established for ballistic transport stating that net cooling is not possible. For conventional transport, net cooling is possible over a broad temperature range, with the range being size-dependent. A temperature clamping scheme for establishing a metastable nonequilibrium stationary state is detailed and followed with discussion of possible applications to on-chip thermoelectric cooling in integrated circuitry and quantum computer systems.

  7. Cooling by Thermodynamic Induction

    Science.gov (United States)

    Patitsas, S. N.

    2016-11-01

    A method is described for cooling conductive channels to below ambient temperature. The thermodynamic induction principle dictates that the electrically biased channel will cool if the electrical conductance decreases with temperature. The extent of this cooling is calculated in detail for both cases of ballistic and conventional transport with specific calculations for carbon nanotubes and conventional metals, followed by discussions for semiconductors, graphene, and metal-insulator transition systems. A theorem is established for ballistic transport stating that net cooling is not possible. For conventional transport, net cooling is possible over a broad temperature range, with the range being size-dependent. A temperature clamping scheme for establishing a metastable nonequilibrium stationary state is detailed and followed with discussion of possible applications to on-chip thermoelectric cooling in integrated circuitry and quantum computer systems.

  8. Radiant Floor Cooling Systems

    DEFF Research Database (Denmark)

    Olesen, Bjarne W.

    2008-01-01

    In many countries, hydronic radiant floor systems are widely used for heating all types of buildings such as residential, churches, gymnasiums, hospitals, hangars, storage buildings, industrial buildings, and smaller offices. However, few systems are used for cooling.This article describes a floor...... cooling system that includes such considerations as thermal comfort of the occupants, which design parameters will influence the cooling capacity and how the system should be controlled. Examples of applications are presented....

  9. Initial Cooling Experiment (ICE)

    CERN Multimedia

    Photographic Service

    1978-01-01

    In 1977, in a record-time of 9 months, the magnets of the g-2 experiment were modified and used to build a proton/antiproton storage ring: the "Initial Cooling Experiment" (ICE). It served for the verification of the cooling methods to be used for the "Antiproton Project". Stochastic cooling was proven the same year, electron cooling followed later. Also, with ICE the experimental lower limit for the antiproton lifetime was raised by 9 orders of magnitude: from 2 microseconds to 32 hours. For its previous life as g-2 storage ring, see 7405430. More on ICE: 7711282, 7809081, 7908242.

  10. High energy electron cooling

    Energy Technology Data Exchange (ETDEWEB)

    Parkhomchuk, V. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation)

    1997-09-01

    High energy electron cooling requires a very cold electron beam. The questions of using electron cooling with and without a magnetic field are presented for discussion at this workshop. The electron cooling method was suggested by G. Budker in the middle sixties. The original idea of the electron cooling was published in 1966. The design activities for the NAP-M project was started in November 1971 and the first run using a proton beam occurred in September 1973. The first experiment with both electron and proton beams was started in May 1974. In this experiment good result was achieved very close to theoretical prediction for a usual two component plasma heat exchange.

  11. Power electronics cooling apparatus

    Science.gov (United States)

    Sanger, Philip Albert; Lindberg, Frank A.; Garcen, Walter

    2000-01-01

    A semiconductor cooling arrangement wherein a semiconductor is affixed to a thermally and electrically conducting carrier such as by brazing. The coefficient of thermal expansion of the semiconductor and carrier are closely matched to one another so that during operation they will not be overstressed mechanically due to thermal cycling. Electrical connection is made to the semiconductor and carrier, and a porous metal heat exchanger is thermally connected to the carrier. The heat exchanger is positioned within an electrically insulating cooling assembly having cooling oil flowing therethrough. The arrangement is particularly well adapted for the cooling of high power switching elements in a power bridge.

  12. Repair of a long nerve defect with a tissue - engineered bioartificial nerve graft: a preliminary report%组织工程化人工神经修复长段神经缺损实验的初步报告

    Institute of Scientific and Technical Information of China (English)

    沈尊理; BergerAlfred; 等

    2001-01-01

    Objective To evaluate the effectiveness of a tissue - engineered artificial nerve on bridging sciatic nerve defect 2.5 cm in length in rats. Methods 90 female Lewis 1W rats aged 2 months were randomly divided into three groups, with 30 in each. Three types of materials were used as graft: group A, collagen nerve tubes with an intrinsic framework seeded with syngeneic Schwann cells, which were referred as tissue - engineered artificial nerves; group B, collagen nerve tubes filled with an intrinsic framework without Schwann cells; and group C, nerve autografts. Six months later, a series of examinations were performed as follows: electrophysiological testing, hisotological staining of nerves and muscles, S - 100 and neurofilament immunostaining as well as axon counts.Results Until now, the assessment has been finished in 21 rats (7 rats in each group). A significant compound muscle action potential (CMAP) was evoked in anterior tibial muscle in group A and C. Regenerated axons were observed in the whole length of nerve grafts, with mild atrophy of their innervating muscles. On the contrary, nothing or only a tiny CMAP was recorded in group B. The distal parts of nerve grafts were filled with fibrotic tissue, while regenerated axons were rarely seen. There was a significant atrophy of the related muscles. Conclusions Our preliminary results demonstrated that the tissue - engineered artificial nerve could effectively repair a long nerve defect in rats.%目的研究组织工程化人工神经修复大鼠2.5 cm长坐骨神经缺损的效果。方法 90只2个月月龄的Lewis 1W雌性大鼠,按手术先后顺序随机分成3个神经移植组, 每组30只。A组:用种植同源雪旺细胞并具有内部支架结构的胶原神经管桥接,即组织工程化人工神经组。B组:用无雪旺细胞但具有内部支架结构的胶原神经管桥接, 即对照组。C组:自体神经移植组。术后6个月,进行神经电生理监测,神经

  13. The Application of Polysaccharide Biocomposites to Repair Cartilage Defects

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    2014-01-01

    Full Text Available Owing to own nature of articular cartilage, it almost has no self-healing ability once damaged. Despite lots of restore technologies having been raised in the past decades, no repair technology has smoothly substituted for damaged cartilage using regenerated cartilage tissue. The approach of tissue engineering opens a door to successfully repairing articular cartilage defects. For instance, grafting of isolated chondrocytes has huge clinical potential for restoration of cartilage tissue and cure of chondral injury. In this paper, SD rats are used as subjects in the experiments, and they are classified into three groups: natural repair (group A, hyaluronic acid repair (group B, and polysaccharide biocomposites repair (hyaluronic acid hydrogel containing chondrocytes, group C. Through the observation of effects of repairing articular cartilage defects, we concluded that cartilage repair effect of polysaccharide biocomposites was the best at every time point, and then the second best was hyaluronic acid repair; both of them were better than natural repair. Polysaccharide biocomposites have good biodegradability and high histocompatibility and promote chondrocytes survival, reproduction, and spliting. Moreover, polysaccharide biocomposites could not only provide the porous network structure but also carry chondrocytes. Consequently hyaluronic acid-based polysaccharide biocomposites are considered to be an ideal biological material for repairing articular cartilage.

  14. Spinal Cord Repair with Engineered Nervous Tissue

    Science.gov (United States)

    2014-04-01

    regeneration—providing the potential to definitively show regeneration of transected axons through a lesion, rather than sparing or sprouting of intact...transection model in order to more definitively test whether axon regeneration was occurring through our grafts. Through H&E staining and...Collagen Only. (A-D) Longitudinal frozen sections of rat TENGs (green) surviving (absent immunosuppression ) and maintaining their morphology both in

  15. Optimality in DNA repair.

    Science.gov (United States)

    Richard, Morgiane; Fryett, Matthew; Miller, Samantha; Booth, Ian; Grebogi, Celso; Moura, Alessandro

    2012-01-07

    DNA within cells is subject to damage from various sources. Organisms have evolved a number of mechanisms to repair DNA damage. The activity of repair enzymes carries its own risk, however, because the repair of two nearby lesions may lead to the breakup of DNA and result in cell death. We propose a mathematical theory of the damage and repair process in the important scenario where lesions are caused in bursts. We use this model to show that there is an optimum level of repair enzymes within cells which optimises the cell's response to damage. This optimal level is explained as the best trade-off between fast repair and a low probability of causing double-stranded breaks. We derive our results analytically and test them using stochastic simulations, and compare our predictions with current biological knowledge.

  16. Elastocaloric cooling: Stretch to actively cool

    Science.gov (United States)

    Ossmer, Hinnerk; Kohl, Manfred

    2016-10-01

    The elastocaloric effect can be exploited in solid-state cooling technologies as an alternative to conventional vapour compression. Now, an elastocaloric device based on the concept of active regeneration achieves a temperature lift of 15.3 K and efficiencies competitive with other caloric-based approaches.

  17. Measure Guideline: Ventilation Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Springer, D.; Dakin, B.; German, A.

    2012-04-01

    The purpose of this measure guideline on ventilation cooling is to provide information on a cost-effective solution for reducing cooling system energy and demand in homes located in hot-dry and cold-dry climates. This guideline provides a prescriptive approach that outlines qualification criteria, selection considerations, and design and installation procedures.

  18. The final cool down

    CERN Multimedia

    Thursday 29th May, the cool-down of the final sector (sector 4-5) of LHC has begun, one week after the start of the cool-down of sector 1-2. It will take five weeks for the sectors to be cooled from room temperature to 5 K and a further two weeks to complete the cool down to 1.9 K and the commissioning of cryogenic instrumentation, as well as to fine tune the cryogenic plants and the cooling loops of cryostats.Nearly a year and half has passed since sector 7-8 was cooled for the first time in January 2007. For Laurent Tavian, AT/CRG Group Leader, reaching the final phase of the cool down is an important milestone, confirming the basic design of the cryogenic system and the ability to operate complete sectors. “All the sectors have to operate at the same time otherwise we cannot inject the beam into the machine. The stability and reliability of the cryogenic system and its utilities are now very important. That will be the new challenge for the coming months,” he explains. The status of the cool down of ...

  19. Solar absorption cooling

    NARCIS (Netherlands)

    Kim, D.-S.

    2007-01-01

    As the world concerns more and more on global climate changes and depleting energy resources, solar cooling technology receives increasing interests from the public as an environment-friendly and sustainable alternative. However, making a competitive solar cooling machine for the market still

  20. Passive evaporative cooling

    NARCIS (Netherlands)

    Tzoulis, A.

    2011-01-01

    This "designers' manual" is made during the TIDO-course AR0531 Smart & Bioclimatic Design. Passive techniques for cooling are a great way to cope with the energy problem of the present day. This manual introduces passive cooling by evaporation. These methods have been used for many years in traditi

  1. Data center cooling method

    Energy Technology Data Exchange (ETDEWEB)

    Chainer, Timothy J.; Dang, Hien P.; Parida, Pritish R.; Schultz, Mark D.; Sharma, Arun

    2015-08-11

    A method aspect for removing heat from a data center may use liquid coolant cooled without vapor compression refrigeration on a liquid cooled information technology equipment rack. The method may also include regulating liquid coolant flow to the data center through a range of liquid coolant flow values with a controller-apparatus based upon information technology equipment temperature threshold of the data center.

  2. Liquid Cooled Garments

    Science.gov (United States)

    1979-01-01

    Astronauts working on the surface of the moon had to wear liquid-cooled garments under their space suits as protection from lunar temperatures which sometimes reach 250 degrees Fahrenheit. In community service projects conducted by NASA's Ames Research Center, the technology developed for astronaut needs has been adapted to portable cooling systems which will permit two youngsters to lead more normal lives.

  3. Solar absorption cooling

    NARCIS (Netherlands)

    Kim, D.-S.

    2007-01-01

    As the world concerns more and more on global climate changes and depleting energy resources, solar cooling technology receives increasing interests from the public as an environment-friendly and sustainable alternative. However, making a competitive solar cooling machine for the market still remain

  4. Coherent electron cooling

    Energy Technology Data Exchange (ETDEWEB)

    Litvinenko,V.

    2009-05-04

    Cooling intense high-energy hadron beams remains a major challenge in modern accelerator physics. Synchrotron radiation is still too feeble, while the efficiency of two other cooling methods, stochastic and electron, falls rapidly either at high bunch intensities (i.e. stochastic of protons) or at high energies (e-cooling). In this talk a specific scheme of a unique cooling technique, Coherent Electron Cooling, will be discussed. The idea of coherent electron cooling using electron beam instabilities was suggested by Derbenev in the early 1980s, but the scheme presented in this talk, with cooling times under an hour for 7 TeV protons in the LHC, would be possible only with present-day accelerator technology. This talk will discuss the principles and the main limitations of the Coherent Electron Cooling process. The talk will describe the main system components, based on a high-gain free electron laser driven by an energy recovery linac, and will present some numerical examples for ions and protons in RHIC and the LHC and for electron-hadron options for these colliders. BNL plans a demonstration of the idea in the near future.

  5. Tissue-engineered acellular matrix material:preparation and application in articular cartilage repair%脱细胞基质材料制备方法及在骨关节软骨损伤修复中的应用

    Institute of Scientific and Technical Information of China (English)

    赵玉果; 李明明

    2016-01-01

      结果与结论:①脱细胞基质组织工程材料交联后呈现为深蓝色,疏松多孔,直径为5 mm,硬度适中,具备一定的弹性;②苏木精-伊红染色不含有细胞碎屑及蓝染的核物质,不存在残留的细胞外基质;③甲苯胺蓝染色为蓝色材料支架孔隙率为90%,溶胀率为(1314±337)%;④脱细胞基质组织组材料1,3,5,7,9 d的A值显著高于纤维样组织组(P OBJECTIVE:To investigate the effect of tissue-engineered acelular matrix in articular cartilage repair. METHODS:Totaly 30 New Zealand rabbits were randomly alottedto fibroid tissue andacelular matrix groups (n=15 per group), and then articular cartilage defect models,4mmin diameter,were established at the white rabbitfemoral condyle. Acelular cartilage matrix scaffold was prepared using bovine knee cartilage, and model rats in the acelular matrix group were repaired with acelular cartilage matrix scaffold and the others in the fibroid tissue group repaired with fibroid tissues. Finaly, repair effects between two groups were compared. RESULTS AND CONCLUSION:The dark blue and porous tissue-engineered acelular matrix material could be found, with a diameter of 5mm and moderate hardness, and exhibited certain flexibility after cross-linking. Hematoxylin-eosin staining showed that cel debris,blue-stainednuclear materials and residual extracelular matrix disappeared. Toluidine blue staining found that the porosity of the blue scaffold was 90%, and the sweling ratio was (1314±337)%. The absorbance value in the acelular matrix group was significantly higher than that in the fibroid tissue group at 1, 3, 5, 7 and 9 days (P< 0.05). In the fibroid tissue group,defectsfiled withnewborn fibrous scars were overt. By contrast, in the acelularmatrix group, the white tissuescovered the defect regionwith smooth surface,and the woundwas basicaly healed,withanunclearboundaryafter 12weeks. Moreover, blue-stained, smal flattened cels appeared

  6. Modeling gasodynamic vortex cooling

    Science.gov (United States)

    Allahverdyan, A. E.; Fauve, S.

    2017-08-01

    We aim at studying gasodynamic vortex cooling in an analytically solvable, thermodynamically consistent model that can explain limitations on the cooling efficiency. To this end, we study an angular plus radial flow between two (coaxial) rotating permeable cylinders. Full account is taken of compressibility, viscosity, and heat conductivity. For a weak inward radial flow the model qualitatively describes the vortex cooling effect, in terms of both temperature and the decrease of the stagnation enthalpy, seen in short uniflow vortex (Ranque) tubes. The cooling does not result from external work and its efficiency is defined as the ratio of the lowest temperature reached adiabatically (for the given pressure gradient) to the lowest temperature actually reached. We show that for the vortex cooling the efficiency is strictly smaller than 1, but in another configuration with an outward radial flow, we find that the efficiency can be larger than 1. This is related to both the geometry and the finite heat conductivity.

  7. Hydronic rooftop cooling systems

    Science.gov (United States)

    Bourne, Richard C.; Lee, Brian Eric; Berman, Mark J.

    2008-01-29

    A roof top cooling unit has an evaporative cooling section that includes at least one evaporative module that pre-cools ventilation air and water; a condenser; a water reservoir and pump that captures and re-circulates water within the evaporative modules; a fan that exhausts air from the building and the evaporative modules and systems that refill and drain the water reservoir. The cooling unit also has a refrigerant section that includes a compressor, an expansion device, evaporator and condenser heat exchangers, and connecting refrigerant piping. Supply air components include a blower, an air filter, a cooling and/or heating coil to condition air for supply to the building, and optional dampers that, in designs that supply less than 100% outdoor air to the building, control the mixture of return and ventilation air.

  8. INITIAL COOLING EXPERIMENT (ICE)

    CERN Multimedia

    1979-01-01

    ICE was built in 1977, using the modified bending magnets of the g-2 muon storage ring (see 7405430). Its purpose was to verify the validity of stochastic and electron cooling for the antiproton project. Stochastic cooling proved a resounding success early in 1978 and the antiproton project could go ahead, now entirely based on stochastic cooling. Electron cooling was experimented with in 1979. The 26 kV equipment is housed in the cage to the left of the picture, adjacent to the "e-cooler" located in a straight section of the ring. With some modifications, the cooler was later transplanted into LEAR (Low Energy Antiproton Ring) and then, with further modifications, into the AD (Antiproton Decelerator), where it cools antiprotons to this day (2006). See also: 7711282, 7802099, 7809081.

  9. INITIAL COOLING EXPERIMENT (ICE)

    CERN Multimedia

    1978-01-01

    ICE was built in 1977, in a record time of 9 months, using the modified bending magnets of the g-2 muon storage ring. Its purpose was to verify the validity of stochastic and electron cooling for the antiproton project, to be launched in 1978. Already early in 1978, stochastic cooling proved a resounding success, such that the antiproton (p-pbar)project was entirely based on it. Tests of electron cooling followed later: protons of 46 MeV kinetic energy were cooled with an electron beam of 26 kV and 1.3 A. The cage seen prominently in the foreground houses the HV equipment, adjacent to the "cooler" installed in a straight section of the ring. With some modifications, the cooler was later transplanted into LEAR (Low Energy Antiproton Ring) and then, with further modifications, into the AD (Antiproton Decelerator), where it cools antiprotons to this day (2006). See also: 7711282, 7802099, 7908242.

  10. 水工环氧防护修补材料应力松弛性能研究%Study of stress relaxation behavior of hydraulic engineering epoxy resin repairing material

    Institute of Scientific and Technical Information of China (English)

    赵波; 李敬玮; 鲁一晖

    2011-01-01

    An experimental study is made on the creep and stress relaxation behavior of the hydraulic engineering epoxy resin repairing material developed in laboratory of IWHR. The material initial elastic modulus of 1. 41 Gpa is determined for the material by the testing of DMTA (Dynamic Mechanical Thermal Analysis) and the stress relaxation function of the material is obtained through the Laplace transform based on the Kelvin model along with the double retardation time and standard linear solid model. The result shows that the result from the standard linear solid model is close to that from the Kelvin model of double retardation time under the temperature of -20 t, however, the result from the Kelvin model is even much more close to the physical character of the material within a bigger temperature scope. The test result indicates that this epoxy resin material has a better mechanical relaxation behavior under a lower temperature condition.%对实验室研制的水工环氧防护材料的蠕变和应力松弛行为进行了试验研究.采用DMTA测试确定材料的起始弹性模量为1.41 GPa,结合蠕变实验结果,采用双推迟时间Kelvin模型和标准线性固体模型,通过Laplace变换得到了材料的应力松弛函数.结果表明:在- 20℃条件下,标准线性固体模型得到的结果接近于双推迟时间的Kelvin模型结果,但较宽温度范围内Kelvin模型更接近于材料的实际物理状态.试验结果表明该环氧修补材料在低温情况下具有较好的力学松弛性能.

  11. Evaluation by Rocket Combustor of C/C Composite Cooled Structure Using Metallic Cooling Tubes

    Science.gov (United States)

    Takegoshi, Masao; Ono, Fumiei; Ueda, Shuichi; Saito, Toshihito; Hayasaka, Osamu

    In this study, the cooling performance of a C/C composite material structure with metallic cooling tubes fixed by elastic force without chemical bonding was evaluated experimentally using combustion gas in a rocket combustor. The C/C composite chamber was covered by a stainless steel outer shell to maintain its airtightness. Gaseous hydrogen as a fuel and gaseous oxygen as an oxidizer were used for the heating test. The surface of these C/C composites was maintained below 1500 K when the combustion gas temperature was about 2800 K and the heat flux to the combustion chamber wall was about 9 MW/m2. No thermal damage was observed on the stainless steel tubes that were in contact with the C/C composite materials. The results of the heating test showed that such a metallic tube-cooled C/C composite structure is able to control the surface temperature as a cooling structure (also as a heat exchanger) as well as indicated the possibility of reducing the amount of coolant even if the thermal load to the engine is high. Thus, application of this metallic tube-cooled C/C composite structure to reusable engines such as a rocket-ramjet combined-cycle engine is expected.

  12. Angiogenesis of tissue engineered bone in the repair of rhesus tibia defects%血管化组织工程骨修复猕猴的胫骨缺损

    Institute of Scientific and Technical Information of China (English)

    曾宪利; 裴国献; 金丹; 唐光辉; 林海宁; 陈书军; 程文俊; 黄爱文

    2006-01-01

    BACKGROUND: Many experiments indicate that the angiogenesis of tissue engineered bone graft plays a key role in the osteogenesis.OBJECTIVE: An experimental pattern was set up designed to prepare a kind of vascularized engineered-bone graft for repairing rhesus tibia defects and analyze the relation of angiogenesis and osteogenesis in vivo by rontgenographic and morphological approaches.DESIGN: Random controlled animal experiment.SETTING: Department of Orthopaedics and Traumatology, Nanfang Hospital, Southern Medical University.MATERIALS: The composite graft was constructed by seeding the induced bone marrow stem cells (BMSCs) on to a beta-tricalcium phosphate(3-TCP) scaffold in vitro, a circular cylinder (20 mm × 8 mm diameter) with a slit (width 2 mm and length 3 mm ) open to both ends and slot. Porosity 60% and pore diameter 100-150 μm. Twenty-nine healthy rhesuses aged 4-5 years and weighted 3.5-5 kg were adopted without gender limitation.METHODS: The experiment was conducted in the Department of Orthopaedics and Traumatology, Nanfan Hospital, Southern Medical University from October 2003 to July 2005. ①Bone-periosteum defect of 20 mm was made in the middle part of right tibia of the 27 rhesuses, and randomly divided into 3 groups equally. ②The defect gaps in fascia-blood vessel group (A) were plugged with in vitro engineered composites constructed by bone marrow stem cells and 3-TCP scaffold, which were totally hugged by a sheet of pedicled deep fascia and additionally a corresponding portion of saphenous artery and veins. The gaps in fascia group (B) and control group(C), however, were inserted with fascia-coated tissue engineered bone and tissue engineered bone only, respectively. Furthermore, two rhesuses without filling materials on the defect were picked up as blanks fixed by steel pins. ③The angiogenesis and osteogenesis for each treatment was assessed by radioactive imaging, roentgenographic analyses, blocking density and vaso-area image analysis

  13. Repairing Peripheral Nerves: Is there a Role for Carbon Nanotubes?

    Science.gov (United States)

    Oprych, Karen M; Whitby, Raymond L D; Mikhalovsky, Sergey V; Tomlins, Paul; Adu, Jimi

    2016-06-01

    Peripheral nerve injury continues to be a major global health problem that can result in debilitating neurological deficits and neuropathic pain. Current state-of-the-art treatment involves reforming the damaged nerve pathway using a nerve autograft. Engineered nerve repair conduits can provide an alternative to the nerve autograft avoiding the inevitable tissue damage caused at the graft donor site. Commercially available nerve repair conduits are currently only considered suitable for repairing small nerve lesions; the design and performance of engineered conduits requires significant improvements to enable their use for repairing larger nerve defects. Carbon nanotubes (CNTs) are an emerging novel material for biomedical applications currently being developed for a range of therapeutic technologies including scaffolds for engineering and interfacing with neurological tissues. CNTs possess a unique set of physicochemical properties that could be useful within nerve repair conduits. This progress report aims to evaluate and consolidate the current literature pertinent to CNTs as a biomaterial for supporting peripheral nerve regeneration. The report is presented in the context of the state-of-the-art in nerve repair conduit design; outlining how CNTs may enhance the performance of next generation peripheral nerve repair conduits.

  14. Repairs of composite structures

    Science.gov (United States)

    Roh, Hee Seok

    Repair on damaged composite panels was conducted. To better understand adhesively bonded repair, the study investigates the effect of design parameters on the joint strength. The design parameters include bondline length, thickness of adherend and type of adhesive. Adhesives considered in this study were tested to measure their tensile material properties. Three types of adhesively bonded joints, single strap, double strap, and single lap joint were considered under changing bondline lengths, thickness of adherend and type of adhesive. Based on lessons learned from bonded joints, a one-sided patch repair method for composite structures was conducted. The composite patch was bonded to the damaged panel by either film adhesive FM-73M or paste adhesive EA-9394 and the residual strengths of the repaired specimens were compared under varying patch sizes. A new repair method using attachments has been suggested to enhance the residual strength. Results obtained through experiments were analyzed using finite element analysis to provide a better repair design and explain the experimental results. It was observed that the residual strength of the repaired specimen was affected by patch length. Method for rapid repairs of damaged composite structures was investigated. The damage was represented by a circular hole in a composite laminated plate. Pre-cured composite patches were bonded with a quick-curing commercial adhesive near (rather than over) the hole. Tensile tests were conducted on specimens repaired with various patch geometries. The test results showed that, among the methods investigated, the best repair method restored over 90% of the original strength of an undamaged panel. The interfacial stresses in the adhesive zone for different patches were calculated in order to understand the efficiencies of the designs of these patch repairs. It was found that the composite patch that yielded the best strength had the lowest interfacial peel stress between the patch and

  15. Second sector cool down

    CERN Multimedia

    2007-01-01

    At the beginning of July, cool-down is starting in the second LHC sector, sector 4-5. The cool down of sector 4-5 may occasionally generate mist at Point 4, like that produced last January (photo) during the cool-down of sector 7-8.Things are getting colder in the LHC. Sector 7-8 has been kept at 1.9 K for three weeks with excellent stability (see Bulletin No. 16-17 of 16 April 2007). The electrical tests in this sector have got opt to a successful start. At the beginning of July the cryogenic teams started to cool a second sector, sector 4-5. At Point 4 in Echenevex, where one of the LHC’s cryogenic plants is located, preparations for the first phase of the cool-down are underway. During this phase, the sector will first be cooled to 80 K (-193°C), the temperature of liquid nitrogen. As for the first sector, 1200 tonnes of liquid nitrogen will be used for the cool-down. In fact, the nitrogen circulates only at the surface in the ...

  16. Measuring the coolness of interactive products: the COOL questionnaire

    DEFF Research Database (Denmark)

    Bruun, Anders; Raptis, Dimitrios; Kjeldskov, Jesper;

    2016-01-01

    is the COOL questionnaire. We based the creation of the questionnaire on literature suggesting that perceived coolness is decomposed to outer cool (the style of a product) and inner cool (the personality characteristics assigned to it). In this paper, we focused on inner cool, and we identified 11 inner cool......, rebelliousness and usability. These factors and their underlying 16 question items comprise the COOL questionnaire. The whole process of creating the questionnaire is presented in detail in this paper and we conclude by discussing our work against related work on coolness and HCI....

  17. Passive Cooling of buildings by night-time ventilation

    DEFF Research Database (Denmark)

    Artmann, Nikolai; Manz, Heinrich; Heiselberg, Per

    Due to an overall trend towards an increasing cooling energy demand in buildings in many European countries over the last few decades, passive cooling by night-time ventilation is seen as a promising concept. However, because of uncertainties in thermal comfort predictions, architects and engineers...... are still hesitant to apply passive cooling techniques. As night-time ventilation is highly dependent on climatic conditions, a method for quantifying the climatic cooling potential was developed and the impact of climate warming was investigated. Although a clear decrease was found, significant potential...... will remain, especially if night-time ventilation is applied in combination with other cooling methods. Building energy simulations showed that the performance of night-time ventilation is also affected by the heat transfer at internal room surfaces, as the cooling effect is very limited for heat transfer...

  18. Altitude Performance and Operational Characteristics of 29-inch-diameter Tail-pipe Burner with Several Fuel Systems and Fuel-cooled Stage-type Flame Holders on J35-A-5 Turbojet Engine / Richard L. Golladay and Harry E. Bloomer

    Science.gov (United States)

    Golladay, Richard L; Bloomer, Harry E

    1950-01-01

    An investigation of tail-pipe burning was conducted in the NACA Lewis altitude wind tunnel with a full-scale turbojet engine and an 29-inch-diameter tail-pipe burner. Effects of fuel distribution and number and arrangement of stages on performance and operational characteristics of several fuel-cooled flame holders are presented and discussed. Operation with a three-stage flame holder having the large stage upstream was the most efficient. Combustion efficiency was slightly increased at high altitudes by injecting fuel upstream of the flame holder.

  19. Workshop on DNA repair.

    NARCIS (Netherlands)

    A.R. Lehmann (Alan); J.H.J. Hoeijmakers (Jan); A.A. van Zeeland (Albert); C.M.P. Backendorf (Claude); B.A. Bridges; A. Collins; R.P.D. Fuchs; G.P. Margison; R. Montesano; E. Moustacchi; A.T. Natarajan; M. Radman; A. Sarasin; E. Seeberg; C.A. Smith; M. Stefanini (Miria); L.H. Thompson; G.P. van der Schans; C.A. Weber (Christine); M.Z. Zdzienika

    1992-01-01

    textabstractA workshop on DNA repair with emphasis on eukaryotic systems was held, under the auspices of the EC Concerted Action on DNA Repair and Cancer, at Noordwijkerhout (The Netherlands) 14-19 April 1991. The local organization of the meeting was done under the auspices of the Medical Genetic C

  20. Laparoscopic lumbar hernia repair.

    Science.gov (United States)

    Madan, Atul K; Ternovits, Craig A; Speck, Karen E; Pritchard, F Elizabeth; Tichansky, David S

    2006-04-01

    Lumbar hernias are rare clinical entities that often pose a challenge for repair. Because of the surrounding anatomy, adequate surgical herniorraphy is often difficult. Minimally invasive surgery has become an option for these hernias. Herein, we describe two patients with lumbar hernias (one with a recurrent traumatic hernia and one with an incisional hernia). Both of these hernias were successfully repaired laparoscopically.

  1. Cool WISPs for stellar cooling excesses

    Energy Technology Data Exchange (ETDEWEB)

    Giannotti, Maurizio [Barry Univ., Miami Shores, FL (United States). Physical Sciences; Irastorza, Igor [Zaragoza Univ. (Spain). Dept. de Fisica Teorica; Redondo, Javier [Zaragoza Univ. (Spain). Dept. de Fisica Teorica; Max-Planck-Institut fuer Physik, Muenchen (Germany); Ringwald, Andreas [DESY Hamburg (Germany). Theory Group

    2015-12-15

    Several stellar systems (white dwarfs, red giants, horizontal branch stars and possibly the neutron star in the supernova remnant Cassiopeia A) show a preference for a mild non-standard cooling mechanism when compared with theoretical models. This exotic cooling could be provided by Weakly Interacting Slim Particles (WISPs), produced in the hot cores and abandoning the star unimpeded, contributing directly to the energy loss. Taken individually, these excesses do not show a strong statistical weight. However, if one mechanism could consistently explain several of them, the hint could be significant. We analyze the hints in terms of neutrino anomalous magnetic moments, minicharged particles, hidden photons and axion-like particles (ALPs). Among them, the ALP represents the best solution. Interestingly, the hinted ALP parameter space is accessible to the next generation proposed ALP searches, such as ALPS II and IAXO.

  2. Cool WISPs for stellar cooling excesses

    CERN Document Server

    Giannotti, Maurizio; Redondo, Javier; Ringwald, Andreas

    2015-01-01

    Several stellar systems (white dwarfs, red giants, horizontal branch stars and possibly the neutron star in the supernova remnant Cassiopeia A) show a preference for a mild non-standard cooling mechanism when compared with theoretical models. This exotic cooling could be provided by Weakly Interacting Slim Particles (WISPs), produced in the hot cores and abandoning the star unimpeded, contributing directly to the energy loss. Taken individually, these excesses do not show a strong statistical weight. However, if one mechanism could consistently explain several of them, the hint could be significant. We analyze the hints in terms of neutrino anomalous magnetic moments, minicharged particles, hidden photons and axion-like particles (ALPs). Among them, the ALP represents the best solution. Interestingly, the hinted ALP parameter space is accessible to the next generation proposed ALP searches, such as ALPS II and IAXO.

  3. Water-cooled electronics

    CERN Document Server

    Dumont, G; Righini, B

    2000-01-01

    LHC experiments demand on cooling of electronic instrumentation will be extremely high. A large number of racks will be located in underground caverns and counting rooms, where cooling by conventional climatisation would be prohibitively expensive. A series of tests on the direct water cooling of VMEbus units and of their standard power supplies is reported. A maximum dissipation of 60 W for each module and more than 1000 W delivered by the power supply to the crate have been reached. These values comply with the VMEbus specifications. (3 refs).

  4. DNA repair protocols

    DEFF Research Database (Denmark)

    Bjergbæk, Lotte

    In its 3rd edition, this Methods in Molecular Biology(TM) book covers the eukaryotic response to genomic insult including advanced protocols and standard techniques in the field of DNA repair. Offers expert guidance for DNA repair, recombination, and replication. Current knowledge of the mechanisms...... that regulate DNA repair has grown significantly over the past years with technology advances such as RNA interference, advanced proteomics and microscopy as well as high throughput screens. The third edition of DNA Repair Protocols covers various aspects of the eukaryotic response to genomic insult including...... recent advanced protocols as well as standard techniques used in the field of DNA repair. Both mammalian and non-mammalian model organisms are covered in the book, and many of the techniques can be applied with only minor modifications to other systems than the one described. Written in the highly...

  5. INTERNAL REPAIR OF PIPELINES

    Energy Technology Data Exchange (ETDEWEB)

    Bill Bruce; Nancy Porter; George Ritter; Matt Boring; Mark Lozev; Ian Harris; Bill Mohr; Dennis Harwig; Robin Gordon; Chris Neary; Mike Sullivan

    2005-07-20

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without

  6. Desiccant-assisted cooling fundamentals and applications

    CERN Document Server

    Brum, Nisio

    2014-01-01

    The increasing concern with indoor air quality has led to air-quality standards with increased ventilation rates. Although increasing the volume flow rate of outside air is advisable from the perspective of air-quality, it is detrimental to energy consumption, since the outside air has to be brought to the comfort condition before it is insufflated to the  conditioned ambient. Moreover, the humidity load carried within outside air has challenging HVAC engineers to design cooling units which are able to satisfactorily handle both sensible and latent contributions to the thermal load. This constitutes a favorable scenario for the use of solid desiccants to assist the cooling units. In fact, desiccant wheels have been increasingly applied by HVAC designers, allowing distinct processes for the air cooling and dehumidification. In fact, the ability of solid desiccants in moisture removal is effective enough to allow the use of evaporative coolers, in opposition to the traditional vapor-compression cycle, resultin...

  7. Ice slurry cooling development and field testing

    Energy Technology Data Exchange (ETDEWEB)

    Kasza, K.E. [Argonne National Lab., IL (United States); Hietala, J. [Northern States Power Co., Minneapolis, MN (United States); Wendland, R.D. [Electric Power Research Inst., Palo Alto, CA (United States); Collins, F. [USDOE, Washington, DC (United States)

    1992-07-01

    A new advanced cooling technology collaborative program is underway involving Argonne National Laboratory (ANL), Northern States Power (NSP) and the Electric Power Research Institute (EPRI). The program will conduct field tests of an ice slurry distributed load network cooling concept at a Northern States Power utility service center to further develop and prove the technology and to facilitate technology transfer to the private sector. The program will further develop at Argonne National Laboratory through laboratory research key components of hardware needed in the field testing and develop an engineering data base needed to support the implementation of the technology. This program will sharply focus and culminate research and development funded by both the US Department of Energy and the Electric Power Research Institute on advanced cooling and load management technology over the last several years.

  8. Ice slurry cooling development and field testing

    Energy Technology Data Exchange (ETDEWEB)

    Kasza, K.E. (Argonne National Lab., IL (United States)); Hietala, J. (Northern States Power Co., Minneapolis, MN (United States)); Wendland, R.D. (Electric Power Research Inst., Palo Alto, CA (United States)); Collins, F. (USDOE, Washington, DC (United States))

    1992-01-01

    A new advanced cooling technology collaborative program is underway involving Argonne National Laboratory (ANL), Northern States Power (NSP) and the Electric Power Research Institute (EPRI). The program will conduct field tests of an ice slurry distributed load network cooling concept at a Northern States Power utility service center to further develop and prove the technology and to facilitate technology transfer to the private sector. The program will further develop at Argonne National Laboratory through laboratory research key components of hardware needed in the field testing and develop an engineering data base needed to support the implementation of the technology. This program will sharply focus and culminate research and development funded by both the US Department of Energy and the Electric Power Research Institute on advanced cooling and load management technology over the last several years.

  9. Cooling Devices in Laser therapy.

    Science.gov (United States)

    Das, Anupam; Sarda, Aarti; De, Abhishek

    2016-01-01

    Cooling devices and methods are now integrated into most laser systems, with a view to protecting the epidermis, reducing pain and erythema and improving the efficacy of laser. On the basis of method employed, it can be divided into contact cooling and non-contact cooling. With respect to timing of irradiation of laser, the nomenclatures include pre-cooling, parallel cooling and post-cooling. The choice of the cooling device is dictated by the laser device, the physician's personal choice with respect to user-friendliness, comfort of the patient, the price and maintenance costs of the device. We hereby briefly review the various techniques of cooling, employed in laser practice.

  10. BMCloud: Minimizing Repair Bandwidth and Maintenance Cost in Cloud Storage

    Directory of Open Access Journals (Sweden)

    Chao Yin

    2013-01-01

    Full Text Available To protect data in cloud storage, fault tolerance and efficient recovery become very important. Recent studies have developed numerous solutions based on erasure code techniques to solve this problem using functional repairs. However, there are two limitations to address. The first one is consistency since the Encoding Matrix (EM is different among clouds. The other one is repairing bandwidth, which is a concern for most of us. We addressed these two problems from both theoretical and practical perspectives. We developed BMCloud, a new low repair bandwidth, low maintenance cost cloud storage system, which aims to reduce repair bandwidth and maintenance cost. The system employs both functional repair and exact repair while it inherits advantages from the both. We propose the JUDGE_STYLE algorithm, which can judge whether the system should adopt exact repair or functional repair. We implemented a networked storage system prototype and demonstrated our findings. Compared with existing solutions, BMCloud can be used in engineering to save repair bandwidth and degrade maintenance significantly.

  11. LHC cooling gains ground

    CERN Multimedia

    Huillet-Miraton Catherine

    The nominal cryogenic conditions of 1.9 K have been achieved in sectors 5-6 and 7-8. This means that a quarter of the machine has reached the nominal conditions for LHC operation, having attained a temperature of below 2 K (-271°C), which is colder than interstellar space! Elsewhere, the cryogenic system in Sector 8-1 has been filled with liquid helium and cooled to 2K and will soon be available for magnet testing. Sectors 6-7 and 2-3 are being cooled down and cool-down operations have started in Sector 3-4. Finally, preparations are in hand for the cool-down of Sector 1-2 in May and of Sector 4-5, which is currently being consolidated. The LHC should be completely cold for the summer. For more information: http://lhc.web.cern.ch/lhc/Cooldown_status.htm.

  12. Why Exercise Is Cool

    Science.gov (United States)

    ... to Know About Puberty Train Your Temper Why Exercise Is Cool KidsHealth > For Kids > Why Exercise Is ... day and your body will thank you later! Exercise Makes Your Heart Happy You may know that ...

  13. Waveguide cooling system

    Science.gov (United States)

    Chen, B. C. J.; Hartop, R. W.

    1981-04-01

    An improved system is described for cooling high power waveguides by the use of cooling ducts extending along the waveguide, which minimizes hot spots at the flanges where waveguide sections are connected together. The cooling duct extends along substantially the full length of the waveguide section, and each flange at the end of the section has a through hole with an inner end connected to the duct and an opposite end that can be aligned with a flange hole in another waveguide section. Earth flange is formed with a drainage groove in its face, between the through hole and the waveguide conduit to prevent leakage of cooling fluid into the waveguide. The ducts have narrowed sections immediately adjacent to the flanges to provide room for the installation of fasteners closely around the waveguide channel.

  14. Warm and Cool Dinosaurs.

    Science.gov (United States)

    Mannlein, Sally

    2001-01-01

    Presents an art activity in which first grade students draw dinosaurs in order to learn about the concept of warm and cool colors. Explains how the activity also helped the students learn about the concept of distance when drawing. (CMK)

  15. Cooling of wood briquettes

    Directory of Open Access Journals (Sweden)

    Adžić Miroljub M.

    2013-01-01

    Full Text Available This paper is concerned with the experimental research of surface temperature of wood briquettes during cooling phase along the cooling line. The cooling phase is an important part of the briquette production technology. It should be performed with care, otherwise the quality of briquettes could deteriorate and possible changes of combustion characteristics of briquettes could happen. The briquette surface temperature was measured with an IR camera and a surface temperature probe at 42 sections. It was found that the temperature of briquette surface dropped from 68 to 34°C after 7 minutes spent at the cooling line. The temperature at the center of briquette, during the 6 hour storage, decreased to 38°C.

  16. INTERNAL REPAIR OF PIPELINES

    Energy Technology Data Exchange (ETDEWEB)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; George Ritter; Bill Mohr; Matt Boring; Nancy Porter; Mike Sullivan; Chris Neary

    2004-12-31

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without

  17. Stacking with stochastic cooling

    Energy Technology Data Exchange (ETDEWEB)

    Caspers, Fritz E-mail: Fritz.Caspers@cern.ch; Moehl, Dieter

    2004-10-11

    Accumulation of large stacks of antiprotons or ions with the aid of stochastic cooling is more delicate than cooling a constant intensity beam. Basically the difficulty stems from the fact that the optimized gain and the cooling rate are inversely proportional to the number of particles 'seen' by the cooling system. Therefore, to maintain fast stacking, the newly injected batch has to be strongly 'protected' from the Schottky noise of the stack. Vice versa the stack has to be efficiently 'shielded' against the high gain cooling system for the injected beam. In the antiproton accumulators with stacking ratios up to 10{sup 5} the problem is solved by radial separation of the injection and the stack orbits in a region of large dispersion. An array of several tapered cooling systems with a matched gain profile provides a continuous particle flux towards the high-density stack core. Shielding of the different systems from each other is obtained both through the spatial separation and via the revolution frequencies (filters). In the 'old AA', where the antiproton collection and stacking was done in one single ring, the injected beam was further shielded during cooling by means of a movable shutter. The complexity of these systems is very high. For more modest stacking ratios, one might use azimuthal rather than radial separation of stack and injected beam. Schematically half of the circumference would be used to accept and cool new beam and the remainder to house the stack. Fast gating is then required between the high gain cooling of the injected beam and the low gain stack cooling. RF-gymnastics are used to merge the pre-cooled batch with the stack, to re-create free space for the next injection, and to capture the new batch. This scheme is less demanding for the storage ring lattice, but at the expense of some reduction in stacking rate. The talk reviews the 'radial' separation schemes and also gives some

  18. Cooling of electronic equipment

    DEFF Research Database (Denmark)

    A. Kristensen, Anders Schmidt

    2003-01-01

    Cooling of electronic equipment is studied. The design size of electronic equipment decrease causing the thermal density to increase. This affect the cooling which can cause for example failures of critical components due to overheating or thermal induced stresses. Initially a pin fin heat sink...... is considered as extruded profiles are inadequate for compact designs. An optimal pin fin shape and configuration is sought also taking manufacturing costs into consideration. Standard methods for geometrical modeling and thermal analysis are applied....

  19. Anomalous law of cooling

    OpenAIRE

    Lapas, Luciano C.; Ferreira, Rogelma M. S.; Oliveira, Fernando A.; Rubí, J. Miguel

    2014-01-01

    We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergo a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton's law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature ma...

  20. Cooling tower waste reduction

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, S.J.; Celeste, J.; Chine, R.; Scott, C.

    1998-05-01

    At Lawrence Livermore National Laboratory (LLNL), the two main cooling tower systems (central and northwest) were upgraded during the summer of 1997 to reduce the generation of hazardous waste. In 1996, these two tower systems generated approximately 135,400 lbs (61,400 kg) of hazardous sludge, which is more than 90 percent of the hazardous waste for the site annually. At both, wet decks (cascade reservoirs) were covered to block sunlight. Covering the cascade reservoirs reduced the amount of chemical conditioners (e.g. algaecide and biocide), required and in turn the amount of waste generated was reduced. Additionally, at the northwest cooling tower system, a sand filtration system was installed to allow cyclical filtering and backflushing, and new pumps, piping, and spray nozzles were installed to increase agitation. the appurtenance upgrade increased the efficiency of the cooling towers. The sand filtration system at the northwest cooling tower system enables operators to continuously maintain the cooling tower water quality without taking the towers out of service. Operational costs (including waste handling and disposal) and maintenance activities are compared for the cooling towers before and after upgrades. Additionally, the effectiveness of the sand filter system in conjunction with the wet deck covers (northwest cooling tower system), versus the cascade reservoir covers alone (south cooling tower south) is discussed. the overall expected return on investment is calculated to be in excess of 250 percent. this upgrade has been incorporated into the 1998 DOE complex-wide water conservation project being led by Sandia National Laboratory/Albuquerque.

  1. Cooling with Superfluid Helium

    CERN Document Server

    Lebrun, P

    2014-01-01

    The technical properties of helium II (‘superfluid’ helium) are presented in view of its applications to the cooling of superconducting devices, particularly in particle accelerators. Cooling schemes are discussed in terms of heat transfer performance and limitations. Large-capacity refrigeration techniques below 2 K are reviewed, with regard to thermodynamic cycles as well as process machinery. Examples drawn from existing or planned projects illustrate the presentation. Keywords: superfluid helium, cryogenics

  2. Laser cooling of solids

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, Richard I [Los Alamos National Laboratory; Sheik-bahae, Mansoor [UNM

    2008-01-01

    We present an overview of solid-state optical refrigeration also known as laser cooling in solids by fluorescence upconversion. The idea of cooling a solid-state optical material by simply shining a laser beam onto it may sound counter intuitive but is rapidly becoming a promising technology for future cryocooler. We chart the evolution of this science in rare-earth doped solids and semiconductors.

  3. 应用组织工程方法修复缺损面肌的动物实验研究%The Application of Tissue Engineering Methods to Repair the Defect of Musculus Facialis:an Animal Experiment Re- search

    Institute of Scientific and Technical Information of China (English)

    刘坤; 王薇; 王少新; 李超; 唐休发; 何等旗; 华成舸; 张兵

    2014-01-01

    目的本研究拟通过用组织工程方法修复缺损面肌,为头颈外科肿瘤术后遗留缺损的动态修复提供新的理论和方法。方法应用细胞培养技术,组织工程方法将SD大鼠成肌细胞与I型胶原复合、培养,并将组织工程化的材料植入成年大鼠面部与面神经断端接触,形成运动单位,以期开发出能替代缺损面肌的仿真生物材料。结果本研究为骨骼肌组织工程中的血管化和神经化提供了重要的参考,其血管化方法可用于其他临床缺血性疾病治疗的研究。故本研究的结果不仅对骨骼肌工程神经支配的问题作出了初步的回答,进一步将在更广的范围里,对血管化和血管生成的研究产生重要影响。结论用组织工程方法修复缺损面肌将会为头颈外科肿瘤术后遗留缺损的修复提供新的选择。%Objective To investigate tissue engineering methods which repair facial defect, it provides a new method for postoperative patients of head and neck surgery.Methods Through cell culture technique and tissue engineering, cultivate myo-blast of SD rat with type I collagen, then the tissue-engineered materials be implanted to facial nerve ending of adult rat, to form the motor unit, in order to develop biological materials to repair the defect in the facial muscles.Results This study has made a prelim-inary answer of the innervation of skeletal muscle engineering problems, it also influences the study of vascularization and angiogene-sis.Conclusion Using tissue engineering methods to repair facial defect of postoperative patients of head and neck surgery will pro-vides a new choice for us.

  4. Experimental study of the decrease in the temperature of an air/water-cooled turbine blade

    Science.gov (United States)

    Ryzhov, A. A.; Sereda, A. V.; Shaiakberov, V. F.; Iskakov, K. M.; Shatalov, Iu. S.

    Results of the full-scale testing of an air/water-cooled deflector-type turbine blade are reported. Data on the decrease in the temperature of the cooling air and of the blade are presented and compared with the calculated values. An analysis of the results indicates that the use of air/water cooling makes it possible to significantly reduce the temperature of the cooling air and of the blade with practically no increase in the engine weight and dimensions.

  5. 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.

  6. Heat pipe turbine vane cooling

    Energy Technology Data Exchange (ETDEWEB)

    Langston, L.; Faghri, A. [Univ. of Connecticut, Storrs, CT (United States)

    1995-10-01

    The applicability of using heat pipe principles to cool gas turbine vanes is addressed in this beginning program. This innovative concept involves fitting out the vane interior as a heat pipe and extending the vane into an adjacent heat sink, thus transferring the vane incident heat transfer through the heat pipe to heat sink. This design provides an extremely high heat transfer rate and an uniform temperature along the vane due to the internal change of phase of the heat pipe working fluid. Furthermore, this technology can also eliminate hot spots at the vane leading and trailing edges and increase the vane life by preventing thermal fatigue cracking. There is also the possibility of requiring no bleed air from the compressor, and therefore eliminating engine performance losses resulting from the diversion of compressor discharge air. Significant improvement in gas turbine performance can be achieved by using heat pipe technology in place of conventional air cooled vanes. A detailed numerical analysis of a heat pipe vane will be made and an experimental model will be designed in the first year of this new program.

  7. Stacking with Stochastic Cooling

    CERN Document Server

    Caspers, Friedhelm

    2004-01-01

    Accumulation of large stacks of antiprotons or ions with the aid of stochastic cooling is more delicate than cooling a constant intensity beam. Basically the difficulty stems from the fact that the optimized gain and the cooling rate are inversely proportional to the number of particles seen by the cooling system. Therefore, to maintain fast stacking, the newly injected batch has to be strongly protected from the Schottky noise of the stack. Vice versa the stack has to be efficiently shielded against the high gain cooling system for the injected beam. In the antiproton accumulators with stacking ratios up to 105, the problem is solved by radial separation of the injection and the stack orbits in a region of large dispersion. An array of several tapered cooling systems with a matched gain profile provides a continuous particle flux towards the high-density stack core. Shielding of the different systems from each other is obtained both through the spatial separation and via the revolution frequencies (filters)....

  8. Research Proposal for the Design and Engineering Phase of a Solar Heating and Cooling System Experiment at the Warner Robins Public Library, Warner Robins, Georgia. Submitted to the United States Energy Research and Development Administration.

    Science.gov (United States)

    Phillips, Warren H.; And Others

    A number of reasons are advanced to include a solar heating and cooling experiment in a library building. The unique aspects of the experiment are to be a seasonally adjustable collector tilt and testing of a new generation of absorption air conditioners. After a brief description of the proposed experiment, the proposal contains forms filed by…

  9. LENS repair and modification of metal NW components:materials and applications guide.

    Energy Technology Data Exchange (ETDEWEB)

    Smugeresky, John E. (Sandia National Laboratories, Livermore, CA); Gill, David Dennis; Oberhaus, Jason (BWXT Y-12); Adams, Thad (Savannah River National Laboratory); VanCamp, Chad (Kansas City Plant)

    2006-11-01

    Laser Engineered Net Shaping{trademark} (LENS{reg_sign}) is a unique, layer additive, metal manufacturing technique that offers the ability to create fully dense metal features and components directly from a computer solid model. LENS offers opportunities to repair and modify components by adding features to existing geometry, refilling holes, repairing weld lips, and many other potential applications. The material deposited has good mechanical properties with strengths typically slightly higher that wrought material due to grain refinement from a quickly cooling weld pool. The result is a material with properties similar to cold worked material, but without the loss in ductility traditionally seen with such treatments. Furthermore, 304L LENS material exhibits good corrosion resistance and hydrogen compatibility. This report gives a background of the LENS process including materials analysis addressing the requirements of a number of different applications. Suggestions are given to aid both the product engineer and the process engineer in the successful utilization of LENS for their applications. The results of testing on interface strength, machinability, weldability, corrosion resistance, geometric effects, heat treatment, and repair strategy testing are all included. Finally, the qualification of the LENS process is briefly discussed to give the user confidence in selecting LENS as the process of choice for high rigor applications. The testing showed LENS components to have capability in repair/modification applications requiring complex castings (W80-3 D-Bottle bracket), thin wall parts requiring metal to be rebuilt onto the part (W87 Firing Set Housing and Y-12 Test Rings), the filling of counterbores for use in reservoir reclamation welding (SRNL hydrogen compatibility study) and the repair of surface defects on pressure vessels (SRNL gas bottle repair). The material is machinable, as testing has shown that LENS deposited material machines similar to that of

  10. Microscale Waste Heat Driven Cooling System

    Science.gov (United States)

    2012-05-02

    to the Inter-Agency Power Group Mechanical Working Group Meeting 2012 about the ammonia-water absorption chiller technology demonstrator developed by...Development and Engineering Center is provided. 15. SUBJECT TERMS absorption ; heat actuated cooling 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...for a Sustainable Future Sustainable Products for a Sustainable Future Acknowledgments US Army - CERDEC Smaller Lighter Co-Generation & Absorption

  11. INTERNAL REPAIR OF PIPELINES

    Energy Technology Data Exchange (ETDEWEB)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; George Ritter; Bill Mohr; Matt Boring; Nancy Porter; Mike Sullivan; Chris Neary

    2004-08-17

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without liners

  12. Comparing Social Stories™ to Cool versus Not Cool

    Science.gov (United States)

    Leaf, Justin B.; Mitchell, Erin; Townley-Cochran, Donna; McEachin, John; Taubman, Mitchell; Leaf, Ronald

    2016-01-01

    In this study we compared the cool versus not cool procedure to Social Stories™ for teaching various social behaviors to one individual diagnosed with autism spectrum disorder. The researchers randomly assigned three social skills to the cool versus not cool procedure and three social skills to the Social Stories™ procedure. Naturalistic probes…

  13. Turbine Airfoil Leading Edge Film Cooling Bibliography: 1972–1998

    Directory of Open Access Journals (Sweden)

    D. M. Kercher

    2000-01-01

    Full Text Available Film cooling for turbine airfoil leading edges has been a common practice for at least 35 years as turbine inlet gas temperatures and pressures have continually increased along with cooling air temperatures for higher engine cycle efficiency. With substantial engine cycle performance improvements from higher gas temperatures, it has become increasingly necessary to film cool nozzle and rotor blade leading edges since external heat transfer coefficients and thus heat load are the highest in this airfoil region. Optimum cooling air requirements in this harsh environment has prompted a significant number of film cooling investigations and analytical studies reported over the past 25 years from academia, industry and government agencies. Substantial progress has been made in understanding the complex nature of leading edge film cooling from airfoil cascades, simulated airfoil leading edges and environment. This bibliography is a report of the open-literature references available which provide information on the complex aero–thermo interaction of leading edge gaseous film cooling with mainstream flow. From much of this investigative information has come successful operational leading edge film cooling design systems capable of sustaining airfoil leading edge durability in very hostile turbine environments.

  14. TURBINE COOLING FLOW AND THE RESULTING DECREASE IN TURBINE EFFICIENCY

    Science.gov (United States)

    Gauntner, J. W.

    1994-01-01

    This algorithm has been developed for calculating both the quantity of compressor bleed flow required to cool a turbine and the resulting decrease in efficiency due to cooling air injected into the gas stream. Because of the trend toward higher turbine inlet temperatures, it is important to accurately predict the required cooling flow. This program is intended for use with axial flow, air-breathing jet propulsion engines with a variety of airfoil cooling configurations. The algorithm results have compared extremely well with figures given by major engine manufacturers for given bulk metal temperatures and cooling configurations. The program calculates the required cooling flow and corresponding decrease in stage efficiency for each row of airfoils throughout the turbine. These values are combined with the thermodynamic efficiency of the uncooled turbine to predict the total bleed airflow required and the altered turbine efficiency. There are ten airfoil cooling configurations and the algorithm allows a different option for each row of cooled airfoils. Materials technology is incorporated and requires the date of the first year of service for the turbine stator vane and rotor blade. The user must specify pressure, temperatures, and gas flows into the turbine. This program is written in FORTRAN IV for batch execution and has been implemented on an IBM 3080 series computer with a central memory requirement of approximately 61K of 8 bit bytes. This program was developed in 1980.

  15. Salvage hypospadias repairs

    Directory of Open Access Journals (Sweden)

    Sripathi V

    2008-01-01

    Full Text Available Aim: Review of our experience and to develop an algorithm for salvage procedures in the management of hypospadias cripples and treatment of urethral strictures following hypospadias repair. Methods: This is a retrospective review of hypospadias surgeries over a 41-month period. Out of a total 168 surgeries, 20 were salvage/re-operative repairs. In three children a Duplay repair was feasible, while in four others a variety of single-stage repairs could be done. The repair was staged in seven children - buccal mucosal grafts (BMGs in five, buccal mucosal tube in one, and skin graft in one. Five children with dense strictures were managed by dorsal BMG inlay grafting in one, vascularized tunical onlay grafting on the ventrum in one, and a free tunical patch in one. Three children were treated by internal urethrotomy and stenting for four weeks with a poor outcome. Results: The age of children ranged from 1.5-15 years (mean 4.5. Follow-up ranged from 3 months to 3.5 years. Excellent results were obtained in 10 children (50% with a well-surfaced erect penis and a slit-like meatus. Glans closure could not be achieved and meatus was coronal in three. Two children developed fistulae following a Duplay repair and following a staged BMG. Three repairs failed completely - a composite repair broke down, a BMG tube stenosed with a proximal leak, and a stricture recurred with loss of a ventral free tunical graft. Conclusions: In salvage procedures performed on hypospadias cripples, a staged repair with buccal mucosa as an inlay in the first stage followed by tubularization 4-6 months later provides good results. A simple algorithm to plan corrective surgery in failed hypospadias cases and obtain satisfactory results is devised.

  16. Cavity Cooling for Ensemble Spin Systems

    Science.gov (United States)

    Cory, David

    2015-03-01

    Recently there has been a surge of interest in exploring thermodynamics in quantum systems where dissipative effects can be exploited to perform useful work. One such example is quantum state engineering where a quantum state of high purity may be prepared by dissipative coupling through a cold thermal bath. This has been used to great effect in many quantum systems where cavity cooling has been used to cool mechanical modes to their quantum ground state through coupling to the resolved sidebands of a high-Q resonator. In this talk we explore how these techniques may be applied to an ensemble spin system. This is an attractive process as it potentially allows for parallel remove of entropy from a large number of quantum systems, enabling an ensemble to achieve a polarization greater than thermal equilibrium, and potentially on a time scale much shorter than thermal relaxation processes. This is achieved by the coupled angular momentum subspaces of the ensemble behaving as larger effective spins, overcoming the weak individual coupling of individual spins to a microwave resonator. Cavity cooling is shown to cool each of these subspaces to their respective ground state, however an additional algorithmic step or dissipative process is required to couple between these subspaces and enable cooling to the full ground state of the joint system.

  17. Measuring the coolness of interactive products: the COOL questionnaire

    DEFF Research Database (Denmark)

    Bruun, Anders; Raptis, Dimitrios; Kjeldskov, Jesper

    2016-01-01

    characteristics. These were used to create an initial pool of question items and 2236 participants were asked to assess 16 mobile devices. By performing exploratory and confirmatory factor analyses, we identified three factors that can measure the perceived inner coolness of interactive products: desirability...... is the COOL questionnaire. We based the creation of the questionnaire on literature suggesting that perceived coolness is decomposed to outer cool (the style of a product) and inner cool (the personality characteristics assigned to it). In this paper, we focused on inner cool, and we identified 11 inner cool...

  18. Half-bead weld repairs for in-service applications

    Energy Technology Data Exchange (ETDEWEB)

    Holz, P.P. Sr.

    1978-01-01

    Successful half- or temper-bead technique weld repairs performed to Section XI of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code guidelines were made to two Heavy-Section Steel Technology Program vessels and a qualification prolongation. Intermediate sized vessels, equivalent in thickness to nuclear pressure vessels, were repair welded and subsequently flawed and pressure tested to approximately 2/sup 1///sub 4/ times design pressure before leakage occurred. Discussed are the standards and procedures used with half-bead repairs, resultant induced metallurgical and stress effects, flaw test criterion, pressure test details and results, and recommendations for further development work for a speedier application process.

  19. Progress of peripheral nerve repair

    Institute of Scientific and Technical Information of China (English)

    陈峥嵘

    2002-01-01

    Study on repair of peripheral nerve injury has been proceeding over a long period of time. With the use of microsurgery technique since 1960s,the quality of nerve repair has been greatly improved. In the past 40 years, with the continuous increase of surgical repair methods, more progress has been made on the basic research of peripheral nerve repair.

  20. Achilles tendon repair

    Science.gov (United States)

    Achilles tendon rupture-surgery; Percutaneous Achilles tendon rupture repair ... To fix your torn Achilles tendon, the surgeon will: Make a cut down the back of your heel Make several small cuts rather than one large cut ...

  1. Diaphragmatic hernia repair - slideshow

    Science.gov (United States)

    ... presentations/100014.htm Diaphragmatic hernia repair - series—Normal anatomy To use the sharing ... Overview The chest cavity includes the heart and lungs. The abdominal cavity includes the liver, the stomach, ...

  2. Eye muscle repair - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100062.htm Eye muscle repair - series—Normal anatomy To use the sharing ... the eyeball to the eye socket. The external muscles of the eye are found behind the conjunctiva. ...

  3. Tracheoesophageal fistula repair - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100103.htm Tracheoesophageal fistula repair - series—Normal anatomy To use the sharing ... Editorial team. Related MedlinePlus Health Topics Esophagus Disorders Fistulas Tracheal Disorders A.D.A.M., Inc. is ...

  4. Inguinal hernia repair - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100027.htm Inguinal hernia repair - series—Normal anatomy To use the sharing ... to slide 4 out of 4 Overview A hernia occurs when part of an organ protrudes through ...

  5. INTERNAL REPAIR OF PIPELINES

    Energy Technology Data Exchange (ETDEWEB)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; Nancy Porter; Mike Sullivan; Chris Neary

    2004-04-12

    The two broad categories of deposited weld metal repair and fiber-reinforced composite liner repair technologies were reviewed for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Preliminary test programs were developed for both deposited weld metal repair and for fiber-reinforced composite liner repair. Evaluation trials have been conducted using a modified fiber-reinforced composite liner provided by RolaTube and pipe sections without liners. All pipe section specimens failed in areas of simulated damage. Pipe sections containing fiber-reinforced composite liners failed at pressures marginally greater than the pipe sections without liners. The next step is to evaluate a liner material with a modulus of elasticity approximately 95% of the modulus of elasticity for steel. Preliminary welding parameters were developed for deposited weld metal repair in preparation of the receipt of Pacific Gas & Electric's internal pipeline welding repair system (that was designed specifically for 559 mm (22 in.) diameter pipe) and the receipt of 559 mm (22 in.) pipe sections from Panhandle Eastern. The next steps are to transfer welding parameters to the PG&E system and to pressure test repaired pipe sections to failure. A survey of pipeline operators was conducted to better understand the needs and performance requirements of the natural gas transmission industry regarding internal repair. Completed surveys contained the following principal conclusions: (1) Use of internal weld repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling (HDD) when a new bore must be created

  6. Pectus excavatum repair - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100035.htm Pectus excavatum repair - series—Normal anatomy To use the sharing ... Go to slide 4 out of 4 Overview Pectus excavatum is a deformity of the front of the ...

  7. Hiatal hernia repair - slideshow

    Science.gov (United States)

    ... presentations/100028.htm Hiatal hernia repair - series—Normal anatomy To use the sharing features on ... Overview The esophagus runs through the diaphragm to the stomach. It functions to carry food from the mouth ...

  8. Repairing ceramic insulating tiles

    Science.gov (United States)

    Dunn, B. R.; Laymance, E. L.

    1980-01-01

    Fused-silica tiles containing large voids or gauges are repaired without adhesives by plug insertion method. Tiles are useful in conduits for high-temperature gases, in furnaces, and in other applications involving heat insulation.

  9. Rotator cuff repair - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100229.htm Rotator cuff repair - series—Normal anatomy To use the sharing ... to slide 4 out of 4 Overview The rotator cuff is a group of muscles and tendons that ...

  10. Cleft lip repair - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100010.htm Cleft lip repair - series—Normal anatomy To use the sharing ... abnormal opening in the middle of the upper lip. A cleft palate is an opening in the roof of ...

  11. The definition of cool

    Energy Technology Data Exchange (ETDEWEB)

    Nichiporuk, A.

    2005-05-01

    A new air cooling system at Agnico-Eagle's LaRonde mine, located in the Abitibi Region of Quebec is described. The new system serves a mine operating at 7,250 plus feet level. The system is installed at the surface; it utilizes ammonia to cool water, which cools the air. The system consists of four compressors which lower the temperature of the ammonia to minus 2 degrees C. Water, which at this temperature is 14 degrees, and ammonia pass through a plate heat exchanger simultaneously, however, without coming into contact with each other. The heat transfer that occurs causes the water's temperature to drop to 2 degrees C. The total volume of water cooled is 220 litres per second. The system is capable of reducing 636,000 cfm of air from 30 degrees C to 6 degrees C, to which 214,000 cfm of non-cooled air is added. This mixture, which is maintained at approximately 8 degrees C throughout the summer season, is sent underground to the deepest parts of the mine. The system runs from June to September, depending on the weather. In the evenings, when the temperature dips to around four to five degrees C, the water is shut down and side doors are opened to prevent the water from freezing.

  12. Performance of a silica gel-water adsorption cooling system for use in small-scale tri-generation applications

    Energy Technology Data Exchange (ETDEWEB)

    De Boer, R.; Smeding, S.F.; Grisel, R.J.H. [ECN Energy Efficiency in the Industry, Petten (Netherlands)

    2006-07-15

    The SOCOOL project focuses on the development of a small-scale combined cold, heat and power (tri-generation) system, which utilises the engine waste heat for cold production. It is demonstrated at the CRF Eco-Canteen in Turin, Italy. The cooling machine is made of two separate sub-cooling systems, each of which is to produce 5 kW of cooling power. One of the cooling systems is driven by 'low-temperature' engine cooling water, the other by 'high-temperature' engine exhaust gases. Tri-generation systems that use heat-driven cooling, offer the possibility of saving 15-20% primary energy. The low-temperature-driven sorption-cooling machine was designed and built at ECN, The Netherlands. Its performance was tested in our own laboratories, before shipment to Turin where it was integrated with the internal combustion engine.

  13. BETTER DUCT SYSTEMS FOR HOME HEATING AND COOLING.

    Energy Technology Data Exchange (ETDEWEB)

    ANDREWS,J.

    2001-01-01

    This is a series of six guides intended to provide a working knowledge of residential heating and cooling duct systems, an understanding of the major issues concerning efficiency, comfort, health, and safety, and practical tips on installation and repair of duct systems. These guides are intended for use by contractors, system designers, advanced technicians, and other HVAC professionals. The first two guides are also intended to be accessible to the general reader.

  14. Aspects of Household Cooling Technology

    OpenAIRE

    Mrzyglod, Matthias; Holzer, Stefan

    2014-01-01

    Actually available household cooling appliances in the highest efficiency class may consume less then 10W average electrical power. To achieve such power consumptions special challenges for the cooling system had to overcome. The related cooling system design has to consider several effects, which arise from the corresponding low cooling capacity demand, start/stop cycles and additional power consumptions by control accessories. The lecture provides symptomatic aspects of cooling technology, ...

  15. Doppler cooling a microsphere

    CERN Document Server

    Barker, P F

    2010-01-01

    Doppler cooling the center-of-mass motion of an optically levitated microsphere via the velocity dependent scattering force from narrow whispering gallery mode (WGM) resonances is described. Light that is red detuned from the WGM resonance can be used to damp the center-of-mass motion in a process analogous to the Doppler cooling of atoms. Leakage of photons out of the microsphere when the incident field is near resonant with the narrow WGM resonance acts to damp the motion of the sphere. The scattering force is not limited by saturation, but can be controlled by the incident power. Cooling times on the order of seconds are calculated for a 20 micron diameter silica microsphere trapped within optical tweezers, with a Doppler temperature limit in the microKelvin regime.

  16. Natural radiative cooling

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.

    1979-01-01

    Natural radiative cooling at night was measured based on the surface-radiation spectrum after the heat balance of the surface exposed to the sun had been reradiated. A concept equivalent to the sky temperature and a concept useful for obtaining the net heat flux are discussed. The highest possible equilibrium temperature of the selective surface can be lowered; however, how to apply this practically is not yet known. A simple radiator, completely enclosed by a transparent screen, can produce a significant and inexpensive cooling effect. The results of experiments carried out in an area such as Padua, Italy, where the climate is not suitable for cooling purposes can still be predicted theoretically. The possibility of using the collector for heat collection during the day and as a radiator at night is indicated.

  17. Clean cooling; Saubere Kuehlung

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1998-07-01

    The round hybrid cooling towers which Balcke-Duerr GmbH is currently building for the 550-MW-IGCC-power-station of a refinery project on Sardinia have to meet particularly stringent requirements as seawater is used for cooling. The advantages are: Avoidance of visible plume with minimal energy consumption, optimal plume exit velocity and discharge, greatest possible stability of the plume column, avoidance of interference and recirculation, high operating reliability of the cooling tower. (orig.) [Deutsch] Derzeit werden die Kuehltuerme fuer ein 550-MW-IGCC-Kraftwerk einer Raffinierie auf Sardinien errichtet. Die Anforderungen an die Technik sind hoch, denn gekuehlt wird mit Seewasser. Zum Einsatz kommen Hybridrundkuehltuerme der Balcke-Duerr GmbH, Ratingen. Damit setzt das Unternehmen diesen Typ erstmals ausserhalb von Deutschland ein. (orig.)

  18. Monitoring Cray Cooling Systems

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, Don E [ORNL; Ezell, Matthew A [ORNL; Becklehimer, Jeff [Cray, Inc.; Donovan, Matthew J [ORNL; Layton, Christopher C [ORNL

    2014-01-01

    While sites generally have systems in place to monitor the health of Cray computers themselves, often the cooling systems are ignored until a computer failure requires investigation into the source of the failure. The Liebert XDP units used to cool the Cray XE/XK models as well as the Cray proprietary cooling system used for the Cray XC30 models provide data useful for health monitoring. Unfortunately, this valuable information is often available only to custom solutions not accessible by a center-wide monitoring system or is simply ignored entirely. In this paper, methods and tools used to harvest the monitoring data available are discussed, and the implementation needed to integrate the data into a center-wide monitoring system at the Oak Ridge National Laboratory is provided.

  19. 应用猪小肠黏膜下层与肌腱细胞构建组织工程支架修复大鼠腹壁缺损的实验研究%Repair of abdominal wall defect with engineered scaffold using tenocytes seeded porcine small intestinal submucosa in rats

    Institute of Scientific and Technical Information of China (English)

    宋致成; 顾岩

    2012-01-01

    目的:应用猪小肠黏膜下层(small intestinal submucosa,SIS)与肌腱细胞构建组织工程支架,研究其在修复腹壁缺损时的生物力学特性.方法:制作SD大鼠腹壁缺损模型,应用所构建的组织工程支架修补缺损,术后4周取样进行大体观察,检测组织学及力学性能.结果:组织工程支架修补术后的SD大鼠无腹部裂开及疝发生,支架与腹腔内脏器有轻微粘连;HE及Masson染色发现支架与肌肉组织交界区有显著新生血管出现及肌肉组织长入.力学性能检测显示组织工程支架的力学强度显著大于SD大鼠腹壁肌肉强度.结论:构建组织工程支架可有效修补大鼠的腹壁缺损.%Objective To investigate the biomechanicai properties of the engineered scaffold using tenocytes seeded small intestinal submucosa (SIS) in abdominal wall defect. Methods Abdominal wall defect was repaired using engineered scaffold in rat modes. The rats were sacrificed after 4 weeks and the sample tissues were analyzed by gross observation, histological method and mechanical testing. Results All rats had no abdominal dehiscence or hernia. The engineered scaffold caused slight adhesion with organs. HE and Masson staining proved the junction between SIS and surrounding tissue had more new vessels. The muscle grew into the engineered scaffold. The mechanical strength of the engineered scaffold was much more than the abdominal wall muscles, which could provide sufficient mechanical strength. Conclusions Engineered scaffold repairing abdominal wall defect is a feasible and effective method.

  20. Control of Non-linear Marine Cooling System

    DEFF Research Database (Denmark)

    Hansen, Michael; Stoustrup, Jakob; Bendtsen, Jan Dimon

    2011-01-01

    We consider the problem of designing control laws for a marine cooling system used for cooling the main engine and auxiliary components aboard several classes of container vessels. We focus on achieving simple set point control for the system and do not consider compensation of the non......-linearities, closed circuit flow dynamics or transport delays that are present in the system. Control laws are therefore designed using classical control theory and the performance of the design is illustrated through two simulation examples....

  1. Anomalous law of cooling.

    Science.gov (United States)

    Lapas, Luciano C; Ferreira, Rogelma M S; Rubí, J Miguel; Oliveira, Fernando A

    2015-03-14

    We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergoes a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton's law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature may oscillate. Despite this anomalous behavior, we show that the variation of entropy remains always positive in accordance with the second law of thermodynamics.

  2. Anomalous law of cooling

    Science.gov (United States)

    Lapas, Luciano C.; Ferreira, Rogelma M. S.; Rubí, J. Miguel; Oliveira, Fernando A.

    2015-03-01

    We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergoes a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton's law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature may oscillate. Despite this anomalous behavior, we show that the variation of entropy remains always positive in accordance with the second law of thermodynamics.

  3. Superconductor rotor cooling system

    Science.gov (United States)

    Gamble, Bruce B.; Sidi-Yekhlef, Ahmed; Schwall, Robert E.; Driscoll, David I.; Shoykhet, Boris A.

    2002-01-01

    A system for cooling a superconductor device includes a cryocooler located in a stationary reference frame and a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with a rotating reference frame in which the superconductor device is located. A method of cooling a superconductor device includes locating a cryocooler in a stationary reference frame, and transferring heat from a superconductor device located in a rotating reference frame to the cryocooler through a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with the rotating reference frame.

  4. A Cool Emperor Penguin

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    哇,这只帝企鹅的胸前居然有个心形!It’s cool!(乐天:没错,它的胸前少了这幺撮毛,应该会感觉挺凉快的)cool在这里可不是“凉快”的意思,而是“酷.帅气”的意思。我们《英语大王》的英文名字就叫English Cool Kids哦!(乐天拿出一副墨镜戴上:

  5. Gas cooled fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1972-06-01

    Although most of the development work on fast breeder reactors has been devoted to the use of liquid metal cooling, interest has been expressed for a number of years in alternative breeder concepts using other coolants. One of a number of concepts in which interest has been retained is the Gas-Cooled Fast Reactor (GCFR). As presently envisioned, it would operate on the uranium-plutonium mixed oxide fuel cycle, similar to that used in the Liquid Metal Fast Breeder Reactor (LMFBR), and would use helium gas as the coolant.

  6. Quantum thermodynamic cooling cycle

    CERN Document Server

    Palao, J P; Gordon, J M; Palao, Jose P.; Kosloff, Ronnie; Gordon, Jeffrey M.

    2001-01-01

    The quantum-mechanical and thermodynamic properties of a 3-level molecular cooling cycle are derived. An inadequacy of earlier models is rectified in accounting for the spontaneous emission and absorption associated with the coupling to the coherent driving field via an environmental reservoir. This additional coupling need not be dissipative, and can provide a thermal driving force - the quantum analog of classical absorption chillers. The dependence of the maximum attainable cooling rate on temperature, at ultra-low temperatures, is determined and shown to respect the recently-established fundamental bound based on the second and third laws of thermodynamics.

  7. Repair of articular cartilage defects in rabbits through tissue-engineered cartilage constructed with chitosan hydrogel and chondrocytes%新型壳聚糖水凝胶结合软骨细胞修复兔关节软骨缺损的实验研究

    Institute of Scientific and Technical Information of China (English)

    Ming ZHAO; Zhu CHEN; Kang LIU; Yu-qing WAN; Xu-dong LI; Xu-wei LUO; Yi-guang BAI; Ze-long YANG; Gang FENG

    2015-01-01

    Objective: In our previous work, we prepared a type of chitosan hydrogel with excelent biocompatibility. In this study, tissue-engineered cartilage constructed with this chitosan hydrogel and costal chondrocytes was used to repair the articular cartilage defects. Methods: Chitosan hydrogels were prepared with a crosslinker formed by com-bining 1,6-disocyanatohexane and polyethylene glycol. Chitosan hydrogel scaffold was seeded with rabbit chondro-cytes that had been cultured for one weekin vitro to form the preliminary tissue-engineered cartilage. This preliminary tissue-engineered cartilage was then transplanted into the defective rabbit articular cartilage. There were three treatment groups: the experimental group received preliminary tissue-engineered cartilage; the blank group received pure chitosan hydrogels; and, the control group had received no implantation. The knee joints were harvested at predetermined time. The repaired cartilage was analyzed through gross morphology, histologicaly and immuno-histochemicaly. The repairs were scored according to the international cartilage repair society (ICRS) standard. Results: The gross morphology results suggested that the defects were repaired completely in the experimental group after twelve weeks. The regenerated tissue connected closely with subchondral bone and the boundary with normal tissue was fuzzy. The cartilage lacuna in the regenerated tissue was similar to normal cartilage lacuna. The results of ICRS gross and histological grading showed that there were significant differences among the three groups (P  创新点:利用自主研发的具有良好生物相容性和稳定性的壳聚糖水凝胶与软骨细胞,在体外初步构建组织工程软骨,并尝试利用其修复缺损的关节软骨,从而为关节软骨缺损的修复提供了一种新的治疗方法。  方法:取兔肋软骨体外培养扩增,获得P2代软骨细胞,将其种植到冻干的壳聚糖水凝胶上,体

  8. Air cooled turbine component having an internal filtration system

    Science.gov (United States)

    Beeck, Alexander R [Orlando, FL

    2012-05-15

    A centrifugal particle separator is provided for removing particles such as microscopic dirt or dust particles from the compressed cooling air prior to reaching and cooling the turbine blades or turbine vanes of a turbine engine. The centrifugal particle separator structure has a substantially cylindrical body with an inlet arranged on a periphery of the substantially cylindrical body. Cooling air enters centrifugal particle separator through the separator inlet port having a linear velocity. When the cooling air impinges the substantially cylindrical body, the linear velocity is transformed into a rotational velocity, separating microscopic particles from the cooling air. Microscopic dust particles exit the centrifugal particle separator through a conical outlet and returned to a working medium.

  9. New Technology in Hydrogen Absorbers for Muon Cooling Channels

    CERN Document Server

    Cummings, M A C

    2005-01-01

    Ionization cooling is the only technique fast enough to cool and focus muons for neutrino factories and muon colliders, and hydrogen is the optimal material for maximum cooling and minimal multiple scattering. Liquid hydrogen absorber R&D for the Muon Collaboration has proceeded on parallel and complementary fronts. The continuing LH2 absorber engineering and technical developments by the MuCool group conducted by ICAR* institutions (NIU, IIT and UIUC), the University of Mississippi and Oxford University, in cooperation with Fermilab, will be summarized, including results from the first hydrogen absorber tests at the newly constructed FNAL Mucool Test Area (MTA). The program includes designs for the high-powered test of an absorber prototype (external heat exchange) at the MTA which are nearing completion to be installed by summer 2005, an alternative absorber design (internal heat exchange) being finalized for the approved cooling experiment (MICE) at Rutherford-Appleton Laboratory, and a novel idea for ...

  10. Real-Time Closed Loop Modulated Turbine Cooling

    Science.gov (United States)

    Shyam, Vikram; Culley, Dennis E.; Eldridge, Jeffrey; Jones, Scott; Woike, Mark; Cuy, Michael

    2014-01-01

    It has been noted by industry that in addition to dramatic variations of temperature over a given blade surface, blade-to-blade variations also exist despite identical design. These variations result from manufacturing variations, uneven wear and deposition over the life of the part as well as limitations in the uniformity of coolant distribution in the baseline cooling design. It is proposed to combine recent advances in optical sensing, actuation, and film cooling concepts to develop a workable active, closed-loop modulated turbine cooling system to improve by 10 to 20 the turbine thermal state over the flight mission, to improve engine life and to dramatically reduce turbine cooling air usage and aircraft fuel burn. A reduction in oxides of nitrogen (NOx) can also be achieved by using the excess coolant to improve mixing in the combustor especially for rotorcraft engines. Recent patents filed by industry and universities relate to modulating endwall cooling using valves. These schemes are complex, add weight and are limited to the endwalls. The novelty of the proposed approach is twofold 1) Fluidic diverters that have no moving parts are used to modulate cooling and can operate under a wide range of conditions and environments. 2) Real-time optical sensing to map the thermal state of the turbine has never been attempted in realistic engine conditions.

  11. Extracellular matrix and tissue engineering applications

    NARCIS (Netherlands)

    Fernandes, Hugo; Moroni, Lorenzo; Blitterswijk, van Clemens; Boer, de Jan

    2009-01-01

    The extracellular matrix is a key component during regeneration and maintenance of tissues and organs, and it therefore plays a critical role in successful tissue engineering as well. Tissue engineers should recognise that engineering technology can be deduced from natural repair processes. Due to a

  12. Ice slurry cooling research: Storage tank ice agglomeration and extraction

    Energy Technology Data Exchange (ETDEWEB)

    Kasza, K. [Argonne National Lab., IL (United States); Hayashi, Kanetoshi [NKK Corp., Kawasaki (Japan)

    1999-08-01

    A new facility has been built to conduct research and development on important issues related to implementing ice slurry cooling technology. Ongoing studies are generating important information on the factors that influence ice particle agglomeration in ice slurry storage tanks. The studies are also addressing the development of methods to minimize and monitor agglomeration and improve the efficiency and controllability of tank extraction of slurry for distribution to cooling loads. These engineering issues impede the utilization of the ice slurry cooling concept that has been under development by various groups.

  13. Application of complex engineering solutions through advanced composite innovation (for repair of degraded buried pipe at Vandellos II Nuclear Power Plant); Reparacion de tuberias de un sistema de servicios no esenciales con recubrimiento interno de fibra de carbono

    Energy Technology Data Exchange (ETDEWEB)

    Bueno, J. M.; Raji, B. B.

    2011-07-01

    This technical presentation is focused on introducing an engineering solution approach and identification of sensitivity of applications of advanced carbon fiber in a pressurized wet environment: Engineering design, quality assurance of installation, inspection, and a comprehensive testing program to validate and bench mark the design data and compliance with code requirements in nuclear power plants.

  14. Measure Guideline: Ventilation Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Springer, D. [Alliance for Residential Building Innovation (ARBI), David, CA (United States); Dakin, B. [Alliance for Residential Building Innovation (ARBI), David, CA (United States); German, A. [Alliance for Residential Building Innovation (ARBI), David, CA (United States)

    2012-04-01

    The purpose of this measure guideline is to provide information on a cost-effective solution for reducing cooling system energy and demand in homes located in hot-dry and cold-dry climates. This guideline provides a prescriptive approach that outlines qualification criteria, selection considerations, and design and installation procedures.

  15. Cooling of Neutron Stars

    Directory of Open Access Journals (Sweden)

    Grigorian H.

    2010-10-01

    Full Text Available We introduce the theoretical basis for modeling the cooling evolution of compact stars starting from Boltzmann equations in curved space-time. We open a discussion on observational verification of different neutron star models by consistent statistics. Particular interest has the question of existence of quark matter deep inside of compact object, which has to have a specific influence on the cooling history of the star. Besides of consideration of several constraints and features of cooling evolution, which are susceptible of being critical for internal structure of hot compact stars we have introduced a method of extraction of the mass distribution of the neutron stars from temperature and age data. The resulting mass distribution has been compared with the one suggested by supernove simulations. This method can be considered as an additional checking tool for the consistency of theoretical modeling of neutron stars. We conclude that the cooling data allowed existence of neutron stars with quark cores even with one-flavor quark matter.

  16. Elementary stochastic cooling

    Energy Technology Data Exchange (ETDEWEB)

    Tollestrup, A.V.; Dugan, G

    1983-12-01

    Major headings in this review include: proton sources; antiproton production; antiproton sources and Liouville, the role of the Debuncher; transverse stochastic cooling, time domain; the accumulator; frequency domain; pickups and kickers; Fokker-Planck equation; calculation of constants in the Fokker-Planck equation; and beam feedback. (GHT)

  17. ELECTRON COOLING FOR RHIC.

    Energy Technology Data Exchange (ETDEWEB)

    BEN-ZVI,I.

    2001-05-13

    The Accelerator Collider Department (CAD) at Brookhaven National Laboratory is operating the Relativistic Heavy Ion Collider (RHIC), which includes the dual-ring, 3.834 km circumference superconducting collider and the venerable AGS as the last part of the RHIC injection chain. CAD is planning on a luminosity upgrade of the machine under the designation RHIC II. One important component of the RHIC II upgrade is electron cooling of RHIC gold ion beams. For this purpose, BNL and the Budker Institute of Nuclear Physics in Novosibirsk entered into a collaboration aimed initially at the development of the electron cooling conceptual design, resolution of technical issues, and finally extend the collaboration towards the construction and commissioning of the cooler. Many of the results presented in this paper are derived from the Electron Cooling for RHIC Design Report [1], produced by the, BINP team within the framework of this collaboration. BNL is also collaborating with Fermi National Laboratory, Thomas Jefferson National Accelerator Facility and the University of Indiana on various aspects of electron cooling.

  18. REPAIR AND STRENGTHENING OF REINFORCED CONCRETE BEAMS USING FIBRE REINFORCED POLIMER (FRP MATERIALS

    Directory of Open Access Journals (Sweden)

    Nihat ÇETİNKAYA

    2004-03-01

    Full Text Available The use of Fibre Reinforced Polimer (FRP materials for the repair and strengthening of Reinforced Concrete structures has become widespread recently. FRP materials are being prefered because they have very high tensile strength, resistance to corrosion and they do not affect the use of the building during the repair and strengthening process. Four reinfoced concrete beams repaired and strengthened with FRP materials have been used in this study which were performed at Pamukkale University-Faculty of Engineering- Civil Engineering Department- Structural Engineering Laboratuary. The behaviour of the beams before and after repair and strengthening was compared by obtaining the load- displacement curves under static loading. In this study, it was observed that the repair and strengthening of reinforced concrete beams by using FRP materials had increased the load carrying capacity significantly.

  19. Improved Concrete Cutting and Excavation Capabilities for Crater Repair Phase 2

    Science.gov (United States)

    2015-05-01

    ER D C/ G SL T R- 14 -8 Improved Concrete Cutting and Excavation Capabilities for Crater Repair Phase 2 G eo te ch ni ca l a nd S tr...Improved Concrete Cutting and Excavation Capabilities for Crater Repair Phase 2 Lulu Edwards, Haley P. Bell, Jay F. Rowland Geotechnical and...Engineer Center to further improve the saw cutting and excavation production rates and robustness of crater repairs in thick portland cement concrete

  20. Waste heat recovery using looped heat pipes for air cooling

    Energy Technology Data Exchange (ETDEWEB)

    Lamfon, N.J.; Akyurt, M.; Najjar, Y.S.H. (King Abdulaziz Univ., Jeddah (Saudi Arabia). Mechanical Engineering Dept.)

    1994-07-01

    A scheme is described for the recovery of waste heat from stacks of gas turbine engines and the utilization of recovered energy for the cooling of ambient air. Relationships are summarized for the modeling of components of the cooling system. Samples are presented from performance data that is predicted by the model. Effect of size and design of system components, as well as operational variables on system performance, are discussed. It is concluded that the single most significant variable in the design of the looped heat-pipe recovery and utilization system is the geometry of the exhaust pipe of the gas turbine engine. (author)

  1. Detecting and Correcting Speech Repairs

    CERN Document Server

    Heeman, P A; Heeman, Peter; Allen, James

    1994-01-01

    Interactive spoken dialog provides many new challenges for spoken language systems. One of the most critical is the prevalence of speech repairs. This paper presents an algorithm that detects and corrects speech repairs based on finding the repair pattern. The repair pattern is built by finding word matches and word replacements, and identifying fragments and editing terms. Rather than using a set of prebuilt templates, we build the pattern on the fly. In a fair test, our method, when combined with a statistical model to filter possible repairs, was successful at detecting and correcting 80\\% of the repairs, without using prosodic information or a parser.

  2. Space Nuclear Reactor Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Poston, David Irvin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-06

    We needed to find a space reactor concept that could be attractive to NASA for flight and proven with a rapid turnaround, low-cost nuclear test. Heat-pipe-cooled reactors coupled to Stirling engines long identified as the easiest path to near-term, low-cost concept.

  3. Stirling engine with pressurized crankcase

    Science.gov (United States)

    Corey, John A.

    1988-01-01

    A two piston Stirling engine wherein the pistons are coupled to a common crankshaft via bearing means, the pistons include pad means to minimize friction between the pistons and the cylinders during reciprocation of the pistons, means for pressurizing the engine crankcase, and means for cooling the crankshaft and the bearing means eliminating the need for oil in the crankcase.

  4. Sorption cooling: a valid extension to passive cooling

    NARCIS (Netherlands)

    Doornink, D.J.; Burger, J.F.; Brake, ter H.J.M.

    2008-01-01

    Passive cooling has shown to be a very dependable cryogenic cooling method for space missions. Several missions employ passive radiators to cool down their delicate sensor systems for many years, without consuming power, without exporting vibrations or producing electromagnetic interference. So for

  5. Comments on Ionization Cooling Channel Characteristics

    CERN Document Server

    Neuffer, David

    2013-01-01

    Ionization cooling channels with a wide variety of characteristics and cooling properties are being developed. These channels can produce cooling performances that are largely consistent with the ionization cooling theory developed previously. In this paper we review ionization cooling theory, discuss its application to presently developing cooling channels, and discuss criteria for optimizing cooling.

  6. Comments on Ionization Cooling Channel Characteristics

    OpenAIRE

    Neuffer, David

    2013-01-01

    Ionization cooling channels with a wide variety of characteristics and cooling properties are being developed. These channels can produce cooling performances that are largely consistent with the ionization cooling theory developed previously. In this paper we review ionization cooling theory, discuss its application to presently developing cooling channels, and discuss criteria for optimizing cooling.

  7. STOCHASTIC COOLING FOR BUNCHED BEAMS.

    Energy Technology Data Exchange (ETDEWEB)

    BLASKIEWICZ, M.

    2005-05-16

    Problems associated with bunched beam stochastic cooling are reviewed. A longitudinal stochastic cooling system for RHIC is under construction and has been partially commissioned. The state of the system and future plans are discussed.

  8. ALP hints from cooling anomalies

    CERN Document Server

    Giannotti, Maurizio

    2015-01-01

    We review the current status of the anomalies in stellar cooling and argue that, among the new physics candidates, an axion-like particle would represent the best option to account for the hinted additional cooling.

  9. Cooling devices in laser therapy

    Directory of Open Access Journals (Sweden)

    Anupam Das

    2016-01-01

    Full Text Available Cooling devices and methods are now integrated into most laser systems, with a view to protecting the epidermis, reducing pain and erythema and improving the efficacy of laser. On the basis of method employed, it can be divided into contact cooling and non-contact cooling. With respect to timing of irradiation of laser, the nomenclatures include pre-cooling, parallel cooling and post-cooling. The choice of the cooling device is dictated by the laser device, the physician′s personal choice with respect to user-friendliness, comfort of the patient, the price and maintenance costs of the device. We hereby briefly review the various techniques of cooling, employed in laser practice.

  10. Numerical Analysis of Supersonic Film Cooling in Supersonic Flow in Hypersonic Inlet with Isolator

    Directory of Open Access Journals (Sweden)

    Silong Zhang

    2014-02-01

    Full Text Available Supersonic film cooling is an efficient method to cool the engine with extremely high heat load. In order to study supersonic film cooling in a real advanced engine, a two-dimensional model of the hypersonic inlet in a scramjet engine with supersonic film cooling in the isolator is built and validated through experimental data. The simulation results show that the cooling effect under different coolant injection angles does not show clear differences; a small injection angle can ensure both the cooling effect and good aerodynamic performances (e.g., flow coefficient of the hypersonic inlet. Under selected coolant injection angle and inlet Mach number, the cooling efficiency increases along with the injection Mach number of the coolant flow, only causing a little total pressure loss in the isolator. Along with the increase of the inlet Mach number of the hypersonic inlet, the cooling efficiency does not present a monotonic change because of the complex shock waves. However, the wall temperature shows a monotonic increase when the inlet Mach number increases. The mass flow rate of coolant flow should be increased to cool the engine more efficiently according to the mass flow rate of the main stream when the inlet Mach number increases.

  11. Scaffolds in Tendon Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Umile Giuseppe Longo

    2012-01-01

    Full Text Available Tissue engineering techniques using novel scaffold materials offer potential alternatives for managing tendon disorders. Tissue engineering strategies to improve tendon repair healing include the use of scaffolds, growth factors, cell seeding, or a combination of these approaches. Scaffolds have been the most common strategy investigated to date. Available scaffolds for tendon repair include both biological scaffolds, obtained from mammalian tissues, and synthetic scaffolds, manufactured from chemical compounds. Preliminary studies support the idea that scaffolds can provide an alternative for tendon augmentation with an enormous therapeutic potential. However, available data are lacking to allow definitive conclusion on the use of scaffolds for tendon augmentation. We review the current basic science and clinical understanding in the field of scaffolds and tissue engineering for tendon repair.

  12. Groin hernia repair in young males: mesh or sutured repair?

    DEFF Research Database (Denmark)

    Bisgaard, T; Bay-Nielsen, M; Kehlet, H

    2010-01-01

    Large-scale data for the optimal inguinal hernia repair in younger men with an indirect hernia is not available. We analysed nationwide data for risk of reoperation in younger men after a primary repair using a Lichtenstein operation or a conventional non-mesh hernia repair....

  13. Carbon nanotubes in neuroregeneration and repair.

    Science.gov (United States)

    Fabbro, Alessandra; Prato, Maurizio; Ballerini, Laura

    2013-12-01

    In the last decade, we have experienced an increasing interest and an improved understanding of the application of nanotechnology to the nervous system. The aim of such studies is that of developing future strategies for tissue repair to promote functional recovery after brain damage. In this framework, carbon nanotube based technologies are emerging as particularly innovative tools due to the outstanding physical properties of these nanomaterials together with their recently documented ability to interface neuronal circuits, synapses and membranes. This review will discuss the state of the art in carbon nanotube technology applied to the development of devices able to drive nerve tissue repair; we will highlight the most exciting findings addressing the impact of carbon nanotubes in nerve tissue engineering, focusing in particular on neuronal differentiation, growth and network reconstruction.

  14. Self pumping magnetic cooling

    Science.gov (United States)

    Chaudhary, V.; Wang, Z.; Ray, A.; Sridhar, I.; Ramanujan, R. V.

    2017-01-01

    Efficient thermal management and heat recovery devices are of high technological significance for innovative energy conservation solutions. We describe a study of a self-pumping magnetic cooling device, which does not require external energy input, employing Mn-Zn ferrite nanoparticles suspended in water. The device performance depends strongly on magnetic field strength, nanoparticle content in the fluid and heat load temperature. Cooling (ΔT) by ~20 °C and ~28 °C was achieved by the application of 0.3 T magnetic field when the initial temperature of the heat load was 64 °C and 87 °C, respectively. These experiments results were in good agreement with simulations performed with COMSOL Multiphysics. Our system is a self-regulating device; as the heat load increases, the magnetization of the ferrofluid decreases; leading to an increase in the fluid velocity and consequently, faster heat transfer from the heat source to the heat sink.

  15. Cooled particle accelerator target

    Science.gov (United States)

    Degtiarenko, Pavel V.

    2005-06-14

    A novel particle beam target comprising: a rotating target disc mounted on a retainer and thermally coupled to a first array of spaced-apart parallel plate fins that extend radially inwardly from the retainer and mesh without physical contact with a second array of spaced-apart parallel plate fins that extend radially outwardly from and are thermally coupled to a cooling mechanism capable of removing heat from said second array of spaced-apart fins and located within the first array of spaced-apart parallel fins. Radiant thermal exchange between the two arrays of parallel plate fins provides removal of heat from the rotating disc. A method of cooling the rotating target is also described.

  16. Water Cooled Mirror Design

    Energy Technology Data Exchange (ETDEWEB)

    Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Holloway, Michael Andrew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pulliam, Elias Noel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-30

    This design is intended to replace the current mirror setup being used for the NorthStar Moly 99 project in order to monitor the target coupon. The existing setup has limited movement for camera alignment and is difficult to align properly. This proposed conceptual design for a water cooled mirror will allow for greater thermal transfer between the mirror and the water block. It will also improve positioning of the mirror by using flexible vacuum hosing and a ball head joint capable of a wide range of motion. Incorporating this design into the target monitoring system will provide more efficient cooling of the mirror which will improve the amount of diffraction caused by the heating of the mirror. The process of aligning the mirror for accurate position will be greatly improved by increasing the range of motion by offering six degrees of freedom.

  17. Magnetic entropy and cooling

    DEFF Research Database (Denmark)

    Hansen, Britt Rosendahl; Kuhn, Luise Theil; Bahl, Christian Robert Haffenden

    2010-01-01

    Some manifestations of magnetism are well-known and utilized on an everyday basis, e.g. using a refrigerator magnet for hanging that important note on the refrigerator door. Others are, so far, more exotic, such as cooling by making use of the magnetocaloric eect. This eect can cause a change...... or nitrogen liquefaction or for room-temperature cooling. The magnetocaloric eect can further be used to determine phase transition boundaries, if a change in the magnetic state occurs at the boundary.In this talk, I will introduce the magnetocaloric eect (MCE) and the two equations, which characterize...... in the temperature of a magnetic material when a magnetic eld is applied or removed. For many years, experimentalists have made use of dilute paramagnetic materials to achieve milliKelvin temperatures by use of the magnetocaloric eect. Also, research is done on materials, which might be used for hydrogen, helium...

  18. Cooling Floor AC Systems

    Science.gov (United States)

    Jun, Lu; Hao, Ding; Hong, Zhang; Ce, Gao Dian

    The present HVAC equipments for the residential buildings in the Hot-summer-and-Cold-winter climate region are still at a high energy consuming level. So that the high efficiency HVAC system is an urgently need for achieving the preset government energy saving goal. With its advantage of highly sanitary, highly comfortable and uniform of temperature field, the hot-water resource floor radiation heating system has been widely accepted. This paper has put forward a new way in air-conditioning, which combines the fresh-air supply unit and such floor radiation system for the dehumidification and cooling in summer or heating in winter. By analyze its advantages and limitations, we found that this so called Cooling/ Heating Floor AC System can improve the IAQ of residential building while keep high efficiency quality. We also recommend a methodology for the HVAC system designing, which will ensure the reduction of energy cost of users.

  19. Heating, ventilation and cooling

    CSIR Research Space (South Africa)

    Osburn, L

    2009-02-01

    Full Text Available content and is evaporated by the air stream with less moisture. Enthalpy wheels are more effective at transferring energy between the air streams as both sensible and latent heat is transferred. Ground-Coupled Heat Exchanger Ground-coupled heat... with high diurnal temperature variations. Evaporative Coolers Evaporative coolers work on the concept that the evaporation of water has a cooling effect on its immediate environment due to the latent heat that it absorbs in order to evaporate...

  20. Cooled Ion Frequency Standard.

    Science.gov (United States)

    2014-09-26

    when the cooling laser is turned off, the ions are heated by: (1) background gas collisions and (2) a plasma heating process which may be " resonant ...causes heating in our Penning traps. One way resonant particle transport is mediated is by misalignm.nt between the trap’s magnetic and electric axis...using computer solutions. The trap of Fig. 1 is noteworthy because although the inner surfaces of the trap are machined with simple conical cuts, the