Sample records for air compressors

  1. 30 CFR 57.13010 - Reciprocating-type air compressors. (United States)


    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Reciprocating-type air compressors. 57.13010... Air and Boilers § 57.13010 Reciprocating-type air compressors. (a) Reciprocating-type air compressors... than 25 percent. (b) However, this standard does not apply to reciprocating-type air compressors...

  2. 30 CFR 56.13010 - Reciprocating-type air compressors. (United States)


    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Reciprocating-type air compressors. 56.13010... and Boilers § 56.13010 Reciprocating-type air compressors. (a) Reciprocating-type air compressors... than 25 percent. (b) However, this standard does not apply to reciprocating-type air compressors...

  3. Air Conditioner Compressor Performance Model

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Ning; Xie, YuLong; Huang, Zhenyu


    During the past three years, the Western Electricity Coordinating Council (WECC) Load Modeling Task Force (LMTF) has led the effort to develop the new modeling approach. As part of this effort, the Bonneville Power Administration (BPA), Southern California Edison (SCE), and Electric Power Research Institute (EPRI) Solutions tested 27 residential air-conditioning units to assess their response to delayed voltage recovery transients. After completing these tests, different modeling approaches were proposed, among them a performance modeling approach that proved to be one of the three favored for its simplicity and ability to recreate different SVR events satisfactorily. Funded by the California Energy Commission (CEC) under its load modeling project, researchers at Pacific Northwest National Laboratory (PNNL) led the follow-on task to analyze the motor testing data to derive the parameters needed to develop a performance models for the single-phase air-conditioning (SPAC) unit. To derive the performance model, PNNL researchers first used the motor voltage and frequency ramping test data to obtain the real (P) and reactive (Q) power versus voltage (V) and frequency (f) curves. Then, curve fitting was used to develop the P-V, Q-V, P-f, and Q-f relationships for motor running and stalling states. The resulting performance model ignores the dynamic response of the air-conditioning motor. Because the inertia of the air-conditioning motor is very small (H<0.05), the motor reaches from one steady state to another in a few cycles. So, the performance model is a fair representation of the motor behaviors in both running and stalling states.

  4. Economics of water injected air screw compressor systems (United States)

    Venu Madhav, K.; Kovačević, A.


    There is a growing need for compressed air free of entrained oil to be used in industry. In many cases it can be supplied by oil flooded screw compressors with multi stage filtration systems, or by oil free screw compressors. However, if water injected screw compressors can be made to operate reliably, they could be more efficient and therefore cheaper to operate. Unfortunately, to date, such machines have proved to be insufficiently reliable and not cost effective. This paper describes an investigation carried out to determine the current limitations of water injected screw compressor systems and how these could be overcome in the 15-315 kW power range and delivery pressures of 6-10 bar. Modern rotor profiles and approach to sealing and cooling allow reasonably inexpensive air end design. The prototype of the water injected screw compressor air system was built and tested for performance and reliability. The water injected compressor system was compared with the oil injected and oil free compressor systems of the equivalent size including the economic analysis based on the lifecycle costs. Based on the obtained results, it was concluded that water injected screw compressor systems could be designed to deliver clean air free of oil contamination with a better user value proposition than the oil injected or oil free screw compressor systems over the considered range of operations.

  5. Economics of water injected air screw compressor systems


    Madhav, K. V.; Kovacevic, A.


    There is a growing need for compressed air free of entrained oil to be used in industry. In many cases it can be supplied by oil flooded screw compressors with multi stage filtration systems, or by oil free screw compressors. However, if water injected screw compressors can be made to operate reliably, they could be more efficient and therefore cheaper to operate. Unfortunately, to date, such machines have proved to be insufficiently reliable and not cost effective. This paper describes an in...

  6. Sound reduction of air compressors using a systematic approach (United States)

    Moylan, Justin Tharp

    The noise emitted by portable electric air compressors can often be a nuisance or potentially hazardous to the operator or others nearby. Therefore, reducing the noise of these air compressors is desired. This research focuses on compressors with a reciprocating piston design as this is the most common type of pump design for portable compressors. An experimental setup was developed to measure the sound and vibration of the air compressors, including testing inside a semi-anechoic chamber. The design of a quiet air compressor was performed in four stages: 1) Teardown and benchmarking of air compressors, 2) Identification and isolation of noise sources, 3) Development of individual means to quiet noise sources, 4) Selection and testing of integrated solutions. The systematic approach and results for each of these stages will be discussed. Two redesigned solutions were developed and measured to be approximately 65% quieter than the previous unmodified compressor. An additional analysis was performed on the solutions selected by the participants involved in the selection process. This analysis involved determining which of the design criteria each participant considered most important when selecting solutions. The results from each participant were then compared to their educational background and experience and correlations were identified. The correlations discovered suggest that educational background and experience may be key determinants for the preference models developed.

  7. Air Compressor Driving with Synchronous Motors at Optimal Parameters

    Directory of Open Access Journals (Sweden)

    Iuliu Petrica


    Full Text Available In this paper a method of optimal compensation of the reactive load by the synchronous motors, driving the air compressors, used in mining enterprises is presented, taking into account that in this case, the great majority of the equipment (compressors, pumps are generally working a constant load.

  8. Air Conditioning Compressor Air Leak Detection by Image Processing Techniques for Industrial Applications

    Directory of Open Access Journals (Sweden)

    Pookongchai Kritsada


    Full Text Available This paper presents method to detect air leakage of an air conditioning compressor using image processing techniques. Quality of air conditioning compressor should not have air leakage. To test an air conditioning compressor leak, air is pumped into a compressor and then submerged into the water tank. If air bubble occurs at surface of the air conditioning compressor, that leakage compressor must be returned for maintenance. In this work a new method to detect leakage and search leakage point with high accuracy, fast, and precise processes was proposed. In a preprocessing procedure to detect the air bubbles, threshold and median filter techniques have been used. Connected component labeling technique is used to detect the air bubbles while blob analysis is searching technique to analyze group of the air bubbles in sequential images. The experiments are tested with proposed algorithm to determine the leakage point of an air conditioning compressor. The location of the leakage point was presented as coordinated point. The results demonstrated that leakage point during process could be accurately detected. The estimation point had error less than 5% compared to the real leakage point.

  9. High Technology Centrifugal Compressor for Commercial Air Conditioning Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ruckes, John


    R&D Dynamics, Bloomfield, CT in partnership with the State of Connecticut has been developing a high technology, oil-free, energy-efficient centrifugal compressor called CENVA for commercial air conditioning systems under a program funded by the US Department of Energy. The CENVA compressor applies the foil bearing technology used in all modern aircraft, civil and military, air conditioning systems. The CENVA compressor will enhance the efficiency of water and air cooled chillers, packaged roof top units, and other air conditioning systems by providing an 18% reduction in energy consumption in the unit capacity range of 25 to 350 tons of refrigeration The technical approach for CENVA involved the design and development of a high-speed, oil-free foil gas bearing-supported two-stage centrifugal compressor, CENVA encompassed the following high technologies, which are not currently utilized in commercial air conditioning systems: Foil gas bearings operating in HFC-134a; Efficient centrifugal impellers and diffusers; High speed motors and drives; and System integration of above technologies. Extensive design, development and testing efforts were carried out. Significant accomplishments achieved under this program are: (1) A total of 26 builds and over 200 tests were successfully completed with successively improved designs; (2) Use of foil gas bearings in refrigerant R134a was successfully proven; (3) A high speed, high power permanent magnet motor was developed; (4) An encoder was used for signal feedback between motor and controller. Due to temperature limitations of the encoder, the compressor could not operate at higher speed and in turn at higher pressure. In order to alleviate this problem a unique sensorless controller was developed; (5) This controller has successfully been tested as stand alone; however, it has not yet been integrated and tested as a system; (6) The compressor successfully operated at water cooled condensing temperatures Due to temperature

  10. Design of Piston Air Compressor Unit Control System based Converter

    Institute of Scientific and Technical Information of China (English)


    <正>Based on the running characteristics and high energy consumption of air compressors in coal mines,an air pressure PID closed loop control system has been designed in this paper.The system is composed of PLC, converter and sensors etc and adopts the control method of converter triple-evaporator which makes air supply"need-based".The designed system has been applied in multiple coal mines and the results show its energy saving is remarkable and potential application is widely.

  11. Numerical Simulation and Performance Analysis of Twin Screw Air Compressors

    Directory of Open Access Journals (Sweden)

    W. S. Lee


    Full Text Available A theoretical model is proposed in this paper in order to study the performance of oil-less and oil-injected twin screw air compressors. Based on this model, a computer simulation program is developed and the effects of different design parameters including rotor profile, geometric clearance, oil-injected angle, oil temperature, oil flow rate, built-in volume ratio and other operation conditions on the performance of twin screw air compressors are investigated. The simulation program gives us output variables such as specific power, compression ratio, compression efficiency, volumetric efficiency, and discharge temperature. Some of the above results are then compared with experimentally measured data and good agreement is found between the simulation results and the measured data.

  12. Impact of the electric compressor for automotive air conditioning system on fuel consumption and performance analysis (United States)

    Zulkifli, A. A.; Dahlan, A. A.; Zulkifli, A. H.; Nasution, H.; Aziz, A. A.; Perang, M. R. M.; Jamil, H. M.; Misseri, M. N.


    Air conditioning system is the biggest auxiliary load in a vehicle where the compressor consumed the largest. Problem with conventional compressor is the cooling capacity cannot be control directly to fulfill the demand of thermal load inside vehicle cabin. This study is conducted experimentally to analyze the difference of fuel usage and air conditioning performance between conventional compressor and electric compressor of the air conditioning system in automobile. The electric compressor is powered by the car battery in non-electric vehicle which the alternator will recharge the battery. The car is setup on a roller dynamometer and the vehicle speed is varied at 0, 30, 60, 90 and 110 km/h at cabin temperature of 25°C and internal heat load of 100 and 400 Watt. The results shows electric compressor has better fuel consumption and coefficient of performance compared to the conventional compressor.

  13. 241-U-701 new compressor building and instrument air piping analyses

    Energy Technology Data Exchange (ETDEWEB)

    Huang, F.H.


    Building anchorage analysis is performed to qualify the design of the new compressor building foundation given in the ECN ``241-U-701 New Compressor Building.`` Recommendations for some changes in the ECN are made accordingly. Calculations show that the 6-in.-slab is capable of supporting the pipe supports, and that the building foundation, air compressor and dryer anchorage, and electric rack are adequate structurally. Analysis also shows that the instrument air piping and pipe supports for the compressed air system meet the applicable code requirements and are acceptable. The building is for the U-Farm instrument air systems.

  14. Evaluation of a natural gas compressor building with switch-back air inlet entrances and ventilated by compressor package coolers

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, Timothy G. [HFP Acoustical Consultants Inc. (United States)], email:


    The booming natural gas market in the Marcellus shale region has seen the appearance of many oil and gas processing stations, the latter generating a great deal of noise, which disturbs local residents. The oil and gas companies have therefore developed a patchwork of noise reduction techniques, from basic mufflers to engineered, sound-proof buildings. This paper focuses on a compromise: a gas compressor station, located in Lycoming County, Pennsylvania, encased in a light-weight, metal building with switch-back air inlet openings for cooling and noise reduction. This case study aims to measure the noise emissions of the compressor, and possibly propose solutions for its mitigation. Since Lycoming County has a fairly stringent policy on noise disturbance, especially for low-frequency sounds, noise emission results showed that switch-back openings and the walls of the compressor building must be mitigated and that action must be taken by the gas company to meet the noise ordinance requirements.

  15. Cleaner production in a remanufacturing process of air compressors. (United States)

    Esquer, Javier; Arvayo, Jose Angel; Alvarez-Chavez, Clara Rosalia; Munguia-Vega, Nora Elba; Velazquez, Luis


    This article provides relevant results of a cleaner production program conducted in a company dedicated to remanufacturing air compressors in the city of Hermosillo, Sonora, Mexico. The overall study design was based on an integration of acknowledged cleaner production and pollution prevention programs. Although this kind of program also involves environmental issues, this study focused on occupational health and safety by addressing different aspects of the work environment: ergonomic, physical (noise and lighting), and chemical. Particularly, ergonomic aspects were evaluated through the Modular Arrangement of Predetermined Time Standards (MODAPTS) method. For physical aspects, noise and lighting were addressed through Standard No. NOM-011-STPS-2001 and Standard No. NOM-025-STPS-2008 respectively. In addition, chemical aspects were analyzed through material safety data sheets and different search tools. Root causes of each risk were identified, and options to prevent, eliminate, and/or reduce each risk have been provided.


    The report discusses the design, building, testing, and delivering to the Environmental Protection Agency of a linear compressor for operation in a 3.0- ton (10.5 kW) residential air-conditioning and heat pumping system. The compressor design evolved from a linear resonant piston...

  17. Low-friction coatings for air bearings in fuel cell air compressors

    Energy Technology Data Exchange (ETDEWEB)

    Ajayi, O. O.; Fenske, G. R.; Erdemir, A.; Woodford, J.; Sitts, J.; Elshot, K.; Griffey, K.


    In an effort to reduce fuel consumption and emissions, hybrid vehicles incorporating fuel cell systems are being developed by automotive manufacturers, their suppliers, federal agencies (specifically, the US Department of Energy) and national laboratories. The fuel cell system will require an air management subsystem that includes a compressor/expander. Certain components in the compressor will require innovative lubrication technology in order to reduce parasitic energy losses and improve their reliability and durability. One such component is the air bearing for air turbocompressors designed and fabricated by Meruit, Inc. Argonne National Laboratory recently developed a carbon-based coating with low friction and wear attributes; this near-frictionless-carbon (NFC) coating is a potential candidate for use in turbocompressor air bearings. The authors present here an evaluation of the Argonne coating for air compressor thrust bearings. With two parallel 440C stainless steel discs in unidirectional sliding contact, the NFC reduced the frictional force four times and the wear rate by more than two orders of magnitude. Wear mechanism on the uncoated surface involved oxidation and production of iron oxide debris. Wear occurred on the coated surfaces primarily by a polishing mechanism.

  18. Transient modeling of an air conditioner with a rapid cycling compressor and multi-indoor units

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wei-Jiang [Institute of Refrigeration and Cryogenics, Shanghai Jiaotong University, Shanghai 200240 (China); Zhang, Chun-Lu [College of Mechanical Engineering, Tongji University, 4800 Cao An Highway, Shanghai 201804 (China)


    Rapid cycling the compressor is an alternative of the variable speed compressor to modulate the capacity of refrigeration systems for the purpose of energy saving at part-load conditions. The multi-evaporator air conditioner combined with the rapid cycling compressor brings difficulties in control design because of the sophisticated system physics and dynamics. In this paper the transient model of a multi-split air conditioner with a digital scroll compressor is developed for predicting the system transients under performance modulations. The predicted cycling dynamics are in good agreement with the experimental data. Based on the validated model, the impact of compressor idle power and cycle period to the part load performance is discussed. (author)

  19. Transient modeling of an air conditioner with a rapid cycling compressor and multi-indoor units

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Weijiang [Institute of Refrigeration and Cryogenics, Shanghai Jiaotong University, Shanghai 200240 (China); Zhang Chunlu, E-mail: [College of Mechanical Engineering, Tongji University, 4800 Cao An Highway, Shanghai 201804 (China)


    Rapid cycling the compressor is an alternative of the variable speed compressor to modulate the capacity of refrigeration systems for the purpose of energy saving at part-load conditions. The multi-evaporator air conditioner combined with the rapid cycling compressor brings difficulties in control design because of the sophisticated system physics and dynamics. In this paper the transient model of a multi-split air conditioner with a digital scroll compressor is developed for predicting the system transients under performance modulations. The predicted cycling dynamics are in good agreement with the experimental data. Based on the validated model, the impact of compressor idle power and cycle period to the part load performance is discussed.

  20. New Energy-Efficient Electromagnetic Clutch for Automotive Air Conditioning Compressors


    Baumgart, Rico; van der Seylberg, Frank; Aurich, Joerg; von Unwerth, Thomas


    Even if the air conditioning is switched off, the internal combustion engine in today’s cars continues to drive the common compressor. To avoid resulting power losses, the automotive industry aspires to apply electromagnetic clutches. When the air conditioning is used, however, CO2-emission increases significantly because the electromag-netic coil consumes electricity. The CO2-reduction per year is consequently very low, which is why new compressor clutches were developed that do not require ...

  1. Comparative Research on Air Conditioner with Gas-injected Rotary Compressor through Injection Port on Blade


    Xingru, Liu; Baolong, Wang; Wenxing, Shi


    Rotary compressors are widely utilized in air conditionders and heat pumps. However, when rotary compressors were applied in room air conditioners, VRFs and domestic water heaters, the systems will experience heavily degradation of the heating capacity and COP as the ambient temperature goes low. Aimed at these problems, considerable research has been carried out to raise a series of solutions, such as economizer technology, cascade-type vapor compression heat pump system and two stage coupli...

  2. Aluminium matrix heterophase composites for air compressor pistons

    Directory of Open Access Journals (Sweden)



    Full Text Available The article presents the results of surface test of composite shaped in the permanent mould casting process. As part of the research anddevelopment project realized in the Department of Materials Technology at the Silesian University of Technology, a pilot plant scale stand was built to manufacture of more than 50 kg suspensions in a single technological cycle. Made in industrial conditions castings to form in the five inner core mould mounted in GM110 permanent mould casting machine confirmed the possibility of the shaping the composite pistons. Castings made from composite suspension AlSi7Mg/SiC and AlSi7Mg/SiC + Cg according to the technology procedure were classified as correct and devoted to the proper machining forming working surfaces of the piston to the air compressor. Comparative tests were performed for the casting of unreinforced AlSi7Mg alloy and composite castings. To assess the ability to fill the mold cavity and the accuracy of mapping used in contour shape FRT analysis of the distance between the grooves on the surface of the piston skirt. Studies have confirmed the differences in the fluidity of alloy matrix and composites suspensions. The difference in the accuracy of the dimensional mapping mould does not disqualify of composite materials, all castings are classified as correct and used for machining.

  3. Compressor-fan unitary structure for air conditioning system (United States)

    Dreiman, N.


    An extremely compact, therefore space saving unitary structure of short axial length is produced by radial integration of a revolving piston rotary compressor and an impeller of a centrifugal fan. The unitary structure employs single motor to run as the compressor so the airflow fan and eliminates duality of motors, related power supply and control elements. Novel revolving piston rotary compressor which provides possibility for such integration comprises the following: a suction gas delivery system which provides cooling of the motor and supplies refrigerant into the suction chamber under higher pressure (supercharged); a modified discharge system and lubricating oil supply system. Axial passages formed in the stationary crankshaft are used to supply discharge gas to a condenser, to return vaporized cooling agent from the evaporator to the suction cavity of the compressor, to pass a lubricant and to accommodate wiring supplying power to the unitary structure driver -external rotor electric motor.

  4. A Supercritical 250 kW Industrial Air Compressor Prototype (United States)

    Lantto, Erkki; Tommila, Ville

    This paper presents the active magnetic bearing control system synthesis and practical rotor dynamic experiences with a supercritical 250 kW turbo compressor. First, the physical boundary conditions of passing the first bending critical speed and feasible bearing characteristics near the critical speed are considered. Then, the control system is synthesized and analyzed using complex formulation. A synchronous response controller is added in parallel with the position controller in order to achieve the preferred bearing characteristics. Finally, measured performance of the control system when passing the critical speed with a real life compressor is presented.

  5. Joule-Thomson cryocooler with neon and nitrogen mixture using commercial air-conditioning compressors (United States)

    Lee, Jisung; Oh, Haejin; Baek, Seungwhan; Lee, Cheonkyu; Jeong, Sangkwon


    A 2-stage mixed refrigerant (MR) Joule-Thomson (JT) cryocooler was designed for cooling high temperature superconducting cable below 70 K. The low temperature cycle was to operate with neon-nitrogen mixture, and the required compression ratio was approximately 24 when the suction pressure was 100 kPa. The high compression ratio of 24, the low pressure of 100 kPa at compressor suction, and the working fluid with high heat of compression were challenging issues to existing typical compression systems. We developed an innovative compression system with commercial oil-lubricated air-conditioning compressors. They were 2-stage rotary compressors originally designed for R410Aand connected in series. The compressors were modified to accommodate effective intercooling at every stage to alleviate compressor overheating problem. Additionally, fine-grade three-stage oil filters, an adsorber, and driers were installed at the discharge line to avoid a potential clogging problem from oil mist and moisture at low temperature sections. The present compression system was specifically demonstrated with a neon-nitrogen MR JT cryocooler. The operating pressure ratio was able to meet the designed specifications, and the recorded no-load mini mum temperature was 63.5 K . Commercial air-conditioning compressors were successfully applied to the high-c ompression ratio MR JT cryocooler with adequate modification using off-the-shelf components.

  6. Integration of MACBETH and COPRAS methods to select air compressor for a textile company

    Directory of Open Access Journals (Sweden)

    Nilsen Kundakcı


    Full Text Available The selection of air compressor is a Multiple Criteria Decision Making (MCDM problem including conflicting criteria and various alternatives. Selecting the appropriate air compressor is an important decision for the company as it affects the energy consumption and operating cost. To aid the decision making process in the companies, MCDM methods are proposed in the literature. In all MCDM methods, the main goal is to select the best alternative or to rank a set of given alternatives. In this paper, the air compressor is selected for a spinning mill of a textile company with an integrated approach based on MACBETH (Measuring Attractiveness by a Categorical Based Evaluation TecHnique and COPRAS (COmplex PRoportional ASsessment methods. MACBETH method is utilized to determine the weights of the criteria. Then COPRAS method is used to determine the ranking of the alternatives and select the best one.

  7. Study on Variable Capacity Control Mechanism of Scroll Compressor for Automotive Air Conditioner (United States)

    Hirano, Takahisa; Shigeoka, Tetsuo

    As for the automotive air conditioner, (1) to keep the automotive cabin temperature in a comfortable region, (2) to improve driving feeling, (3) to drive the air conditioning system economically through all seasons, are universally required. Recently, from these points, compressors with variable capacity control mechanism for automotive air conditioners have been remarkably requested. We have developed a scroll comoressor with variable capacity control mechanism. The capacity control mechanism, which changes the channel area of the bypass hole continuously, according to the suction gas pressure and the discharge gas pressure, has been developed. In this report, we describe the mechanism of variable capacity control and the performance simulation program that has been developed for the scroll compressor. Further, we describe the measuring results of cylinder pressure behavior, the results of energy loss analysis and the effect of comfort, drivability, power saving in the refrigerating cycle using the developed capacity control compressor.

  8. Experimental study of a mixed refrigerant Joule-Thomson cryocooler using a commercial air-conditioning scroll compressor (United States)

    Lee, Jisung; Lee, Kyungsoo; Jeong, Sangkwon


    Mixed refrigerant Joule-Thomson (MR J-T) cryocoolers have been used to create cryogenic temperatures and are simple, efficient, cheap, and durable. However, compressors for MR J-T cryocoolers still require optimization. As the MR J-T cryocooler uses a commercial scroll compressor developed for air-conditioning systems, compressor overheating due to the use of less optimized refrigerants may not be negligible, and could cause compressor malfunction due to burn-out of scroll tip seals. Therefore, in the present study, the authors propose procedures to optimize compressor operation to avoid the overheating issue when the MR J-T cryocooler is used with a commercial oil lubricated scroll compressor, and the present experimental results obtained for a MR J-T cryocooler. A single stage 1.49 kW (2 HP) scroll compressor designed for R22 utilizing a mixture of nitrogen and hydrocarbons was used in the present study. As was expected, compressor overheating and irreversible high temperatures at a compressor discharge port were found at the beginning of compressor operation, which is critical, and hence, the authors used a water injection cooling system for the compressor to alleviate temperature overshooting. In addition, a portion of refrigerant in the high-pressure stream was by-passed into the compressor suction port. This allowed an adequate compression ratio, prevented excessive temperature increases at the compressor discharge, and eventually enabled the MR J-T cryocooler to operate stably at 121 K. The study shows that commercial oil lubricated scroll compressors can be used for MR J-T cryocooling systems if care is exercised to avoid compressor overheating.

  9. Technical Requirements and Principles for the Standards Development of the Key Parts for Rotor Air-conditioning Compressors

    Institute of Scientific and Technical Information of China (English)

    Sun Min; Wen Yun; Fan Zhangzeng


    ntroductionSince 2000,air-conditioning sales continues to grow,and the development of air-conditioning market makes a booming market of compressor.At the present time,compressor production rising all the way,and the sales steps up the new steps constantly.Tendency chart is shown in figure 1.Rotor compressor with its simple structure,small volume,light weight,easy processed mechanical parts,reliable operation and other excellent characteristics occupied the dominant position in the market.Compared with reciprocating compressor on the same application situation,decreased in the size by 40%~50%,weight was reduced by 40%~50%.But there were also disadvantages,mainly large friction loss,friction power consumption was about 10%of compressor's total power input.

  10. Experimental evidence of the thermal effect of lubricating oil sprayed in sliding-vane air compressors

    Directory of Open Access Journals (Sweden)

    Gianluca Valenti


    Full Text Available A way to increase the efficiency of positive-displacement air compressor is spraying the lube oil to exploit it not only as lubricating and sealing agent but also as thermal ballast. This work seeks the experimental evidence in sliding-vane compressors by measuring the air standard volume flow rate and the electrical power input of three diverse configurations. The first configuration, taken as the reference, employs a conventional injection system comprising calibrated straight orifices. The other two, referred to as advanced, adopt smaller orifices and pressure-swirl full-cone nozzles designed for the purpose; the third configuration utilizes a pump to boost the oil pressure. The laser imagining technique shows that the nozzles generate sprays that break-up within a short distance into spherical droplets, ligaments, ramifications and undefined structures. Tests on the packaged compressors reveal that the advanced configurations provide almost the same air flow rate while utilizing half of the oil because the sprays generate a good sealing. Moreover, the sprayed oil is acting as a thermal ballast because the electrical input is reduced by 3.5% and 3.0%, respectively, if the pump is present or not , while the specific energy requirement, accounting for the slightly reduced air flow, by 2.4% and 2.9%, respectively.

  11. Comparison and Evaluation of a New Innovative Drive Concept for the Air Conditioning Compressor of Electric Vehicles



    The development of an energy efficient air conditioning system for electric vehicles is an ever increasing challenge, because the cooling as well as the heating of the passenger cell reduces the cruising range dramatically. Almost always the compressor of the air conditioning system in electric cars is a scroll compressor with a separate electric motor and appropriate power electronics. However, this solution is critical in terms of the installation space, the weight and also the costs. There...

  12. Experiments of effects of inlet-air distortion on aerodynamic performance in transonic compressor

    Institute of Scientific and Technical Information of China (English)

    LI Mao-yi; YUAN Wei; LU Ya-jun; SONG Xi-zhen; LU Li-peng


    The inlet-air distortion which was caused by high angle-of-attack flight was simulated by plugboard.Experiments were conducted on a transonic axial-flow compressor's rotor at 98% rotating speed.The flow field characteristics and mechanism of performance degradation were analyzed in detail.The compressor inlet was divided into four sectors at circumference under inlet-air distortion.They were undistorted sector,transition sector A where the rotor was rotating into the distortion sector,distorted sector and transition sector B where the rotor was rotating out of the distortion sector.The experimental results show that compared with undistorted sector,there is a subsonic flow in transition sector A,so the pressure ratio is decreased by a large margin in this sector.However,the shock wave is enhanced in distortion sector and transition sector B,and thus the pressure ratio increases in these sectors.Because of the different works at circumference,the phase angle of total pressure changes 90° when the inlet total pressure distortion passes through compressor rotor.In addition,the frequency and amplitude of disturbances in front of the rotor strengthenes under inlet distortion,so the unstable flow would take place in advance.In addition,the position of stall inception is in one of the transition sectors.


    Institute of Scientific and Technical Information of China (English)


    A novel variable displacement compressor (VDC) for automotive air conditioner (AAC) is introduced, which inherits the advantages of common wobble plate type VDC. It has fewer parts and makes less noise, and inst ead of pneumatic valve the displacement is controlled by electronic control valv e. In order to know the control mechanism well and get a good control effect, a mathematical model for the variable displacement mechanism is developed accordin g to the geometrical and kinematical information of the compressor. Using the mo del, the effect of relevant parameters on variable displace control is estimated . It is helpful to make the optimum decision in the flow control of AAC. As the novel displacement control device, the structure and control rule of electronic control valve is introduced. It can get better effect than the conventional pneu matic valves. And by using this new electronic control device, the optimum syste mic control of AAC is available.



    D. Rajenthirakumar; Nandhakumar, S.


    In this competitive world, any company has to fulfill its customer needs to survive in the market. Lean manufacturing is a technique that can be adopted in a company to improve the quality of its products, reduce the cost of the production and also deliver the products in less time. The goal of this work is to show the applicability of lean manufacturing’s body of knowledge in a screw air compressor manufacturing company. Here, the main objective is to evolve and te...

  15. Mid-section of a can-annular gas turbine engine with a radial air flow discharged from the compressor section

    Energy Technology Data Exchange (ETDEWEB)

    Little, David A.; McQuiggan, Gerard; Wasdell, David L.


    A midframe portion (213) of a gas turbine engine (210) is presented, and includes a compressor section (212) configured to discharge an air flow (211) directed in a radial direction from an outlet of the compressor section (212). Additionally, the midframe portion (213) includes a manifold (214) to directly couple the air flow (211) from the compressor section (212) outlet to an inlet of a respective combustor head (218) of the midframe portion (213).

  16. Japanese and American competition in the development of scroll compressors and its impact on the American air conditioning industry

    Energy Technology Data Exchange (ETDEWEB)

    Ushimaru, Kenji (Energy International, Inc., Bellevue, WA (USA))


    This report examines the technological development of scroll compressors and its impact on the air conditioning equipment industry. Scroll compressors, although considered to be the compressors of the future for energy-efficient residential heat pumps and possibly for many other applications, are difficult to manufacture on a volume-production base. The manufacturing process requires computer-aided, numerically controlled tools for high-precision fabrication of major parts. Japan implemented a global strategy for dominating the technological world market in the 1970s, and scroll compressor technology benefited from the advent of new-generation machine tools. As a result, if American manufacturers of scroll compressors purchase or are essentially forced to purchase numerically controlled tools from Japan in the future, they will then become dependent on their own competitors because the same Japanese conglomerates that make numerically controlled tools also make scroll compressors. This study illustrates the importance of the basic machine tool industry to the health of the US economy. Without a strong machine tool industry, it is difficult for American manufacturers to put innovations, whether patented or not, into production. As we experience transformation in the air conditioning and refrigeration market, it will be critical to establish a consistent national policy to provide healthy competition among producers, to promote innovation within the industry, to enhance assimilation of new technology, and to eliminate practices that are incompatible with these goals. 72 refs., 8 figs., 1 tab.

  17. Experimental Investigation of an Automobile Air-Conditioning System using Integrated Brushless Direct Current Motor Rotary Compressor

    Directory of Open Access Journals (Sweden)

    Sukri M.F.


    Full Text Available The present study presents an experimental investigation on the effect of condenser air inlet temperature and dimensionless parameter of X on the performance of automobile air-conditioning (AAC system using integrated brushless direct current motor-rotary compressor and electronic expansion valve. The other components of AAC system are from original component of AAC system used for medium size passenger car. The experimental results showed that the increment of the condenser air inlet temperature and X caused an increase in condensing temperature, cooling capacity and compressor work, while decreasing the coefficient of performance (COP. Meanwhile, the evaporating temperature increase with the increment of condenser air inlet temperature, but decrease with decrement of X. In general, AAC system have to work at higher value of X in order to produce more cooling capacity, thereby increment in compressor work also occurs due to energy balance. However, at higher value of X, the COP of the system dropped due to dominant increase in compressor power, as opposed to a rise in cooling capacity. Due to this reason, the best operation of this compressor occurs at X = 4.96 for constant T5 (35ºC, or at T5 = 30ºC for constant X (4.96.

  18. Development of light-weight Al scroll compressor for car air conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Park, I.; Park, Y. [Dept. of Metallurgical Engineering, Pusan National Univ., Pusan (Korea); Choi, I. [Dept. of Mechanical and Materials Engineering, Korea Maritime Univ., Pusan (Korea)


    The scroll compressor with high cooling efficiency and lower oscillating noise can be a candidate material for a part of car air conditioner, household air conditioner and so on. When Al alloy with high strength is used for scroll compressor instead of cast iron, rotation speed can be increased by weight reduction. To design Al alloy which has enough mechanical properties to replace cast iron, the effect of alloying elements, such as Si(13-15%), Cu(4-5%), and Mg(0.5-1%) and cooling rates on the mechanical properties of squeeze cast Al alloy was studied. The influence of Sr and P modification treatment on Si morphology was also studied. Aluminum alloy over 400MPa of tensile strength and 2% elongation was developed. Al scroll samples was fabricated by squeeze casting machine(UBE 800ton) with using 2 cavity mold. Flow-3D which is a three dimensional melt flow analysis program was used to find most proper mold design and optimum process conditions for squeeze casting before making samples. Relationship between secondary dendrite arm spacing and cooling rate was simulated by Flow-3D and compared with experimental results. (orig.)


    Directory of Open Access Journals (Sweden)

    D. Rajenthirakumar


    Full Text Available In this competitive world, any company has to fulfill its customer needs to survive in the market. Lean manufacturing is a technique that can be adopted in a company to improve the quality of its products, reduce the cost of the production and also deliver the products in less time. The goal of this work is to show the applicability of lean manufacturing’s body of knowledge in a screw air compressor manufacturing company. Here, the main objective is to evolve and test several methodologies to eliminate wastes in the assembly line as the company at present unable to meet the customer demand. A systematic approach is suggested for the implementation of lean principles to showcase that lean could be applied to the compressor assembly line to enhance the productivity thereby making the line more efficient. In the current assembly line there was no work standardization followed by absence of kaizen that has led to an increased assembly time. Thus with the help of lean tools and techniques such as 5S, kaizen, standardization, visual management, poke yoke and string diagram the total cycle time has been reduced from 236 to 209 minutes. This reduction has benefitted the company in meeting the customer demand, increased profit and work satisfaction.

  20. Performance of R-410A Alternative Refrigerants in a Reciprocating Compressor Designed for Air Conditioning Applications

    Energy Technology Data Exchange (ETDEWEB)

    Shrestha, Som S [ORNL; Vineyard, Edward Allan [ORNL; Mumpower, Kevin [Bristol Compressors International, Inc.


    In response to environmental concerns raised by the use of refrigerants with high Global Warming Potential (GWP), the Air-Conditioning, Heating, and Refrigeration Institute (AHRI) has launched an industry-wide cooperative research program, referred to as the Low-GWP Alternative Refrigerants Evaluation Program (AREP), to identify and evaluate promising alternative refrigerants for major product categories. After successfully completing the first phase of the program in December 2013, AHRI launched a second phase of the Low-GWP AREP in 2014 to continue research in areas that were not previously addressed, including refrigerants in high ambient conditions, refrigerants in applications not tested in the first phase, and new refrigerants identified since testing for the program began. Although the Ozone Depletion Potential of R-410A is zero, this refrigerant is under scrutiny due to its high GWP. Several candidate alternative refrigerants have already demonstrated low global warming potential. Performance of these low-GWP alternative refrigerants is being evaluated for Air conditioning and heat pump applications to ensure acceptable system capacity and efficiency. This paper reports the results of a series of compressor calorimeter tests conducted for the second phase of the AREP to evaluate the performance of R-410A alternative refrigerants in a reciprocating compressor designed for air conditioning systems. It compares performance of alternative refrigerants ARM-71A, L41-1, DR-5A, D2Y-60, and R-32 to that of R-410A over a wide range of operating conditions. The tests showed that, in general, cooling capacities were slightly lower (except for the R-32), but energy efficiency ratios (EER) of the alternative refrigerants were comparable to that of R-410A.

  1. Modeling and control of a proton exchange membrane fuel cell with the air compressor according to requested electrical current

    Directory of Open Access Journals (Sweden)

    Malekbala Mohammad Rahim


    Full Text Available The aim of this paper is to design and investigate the dynamic behavior of a PEM fuel cell system. Dynamic analysis of a PEM fuel cell system has been done in Matlab\\Simulink software according to electrical current that has been applied from hybrid system. In addition, dynamical fuel cell system has been explained according to oriented control that is started from air injection compressor model. Also hydrogen valve actuator has been controlled according to the compressor model. The results of the fuel cell dynamic model as well as the applied compressor model are fully validated based on the available results in the open literature. Finally, the effects of several operating parameters of the fuel cell system such as anode and cathode pressures, cell voltage, compressor voltage, compressor mass flow rate variation with respect to inlet pressure ratio, net and stack powers on the dynamic behavior of the hybrid system are investigated. The results show that the model can predict the dynamic behavior of the fuel cell system accurately and it can be used directly for any control purposes.

  2. 变频器在空压机恒压供气改造中的应用%Inverter in Transformation of Air Compressor Constant Pressure Air Supply

    Institute of Scientific and Technical Information of China (English)



    Exist for traditional air compressor control to no-load operating power factor is low, serious power waste and two-cylinder temperature rise higher defect, through the use of inverter control system of the air compressor, piston compressor actual operation constant pressure air supply energy-saving air compressor running after the transformation was complete, stable, significant energy savings, and also to meet the requirements of production process.%针对空压机传统控制方式存在空载运行功率因数低、电能浪费严重及二级缸温升高等缺陷,同时根据活塞式空压机实际运行情况,通过采用变频器对空压机控制系统进行恒压供气节能改造.改造完成后,空压机运行稳定、节能效果明显,也满足了生产工艺的要求.

  3. Thermal Performance Analysis of Small Hermetic Refrigeration and Air-Conditioning Compressors (United States)

    Kim, Man-Hoe; Bullard, Clark W.

    A simple physical model for small hermetic reciprocating, rotary and scroll compressors has been developed based on thermodynamic principles and large data sets from the compressor calorimeter and in situ tests. Pressure losses along the refrigerant path are neglected and a compression process is assumed isentropic. A mass flow rate model reflects clearance volumetric efficiency and simulates suction gas heating using an effectiveness method. Compressor work is calculated using the compressor efficiency represented by only two empirical parameters. A linear relationship between the discharge and shell temperatures is extracted from the large data sets and applied to the model for calculating the discharge temperature. Another experimental observation indicates that the specific volumes at the suction and discharge ports of the cylinder have linear relationships with the specific volumes at the compressor suction and discharge. Those relationships can be used for the compressor model and the possibility is reported. The models developed using physical principles and experimental observations can predict the mass flow rate and power consumption within ±3.0% accuracy.

  4. Energy saving avoiding the centrifugal motor-compressors air vents discharge to the surrounding atmosphere; Ahorro de energia evitando venteo de aire a la atmosfera en motocompresores centrifugos

    Energy Technology Data Exchange (ETDEWEB)

    Serrano, Alex [Compressor Controls Corporation, Houston, TX (United States)


    The motor-compressors are a key part of the industrial processes. The reliability and efficient operation of a compressor is critical. The surge phenomenon is a threat in the reliability of a compressor and therefore for the process. Surge, in a centrifugal compressor is defined as a dramatic flow and pressure drop, including back-flow. This is always a significant process disturbance. Continuous surge results into costly process shutdowns and mechanical damages. To prevent surge, and control the discharge pressure with simple or obsolete controls it is needed to vent air to the surrounding atmosphere. This form of control is very inefficient and costly. An advanced control with leading technology, besides providing an economical value preventing surge damages, offers substantial energy saving reducing or eliminating the venting of air to the atmosphere. [Espanol] Los motocompresores son un aparte clave de los procesos industriales. La confiable y eficiente operacion de un compresor es critica. El fenomeno de surge es una amenaza a la confiabilidad de un compresor y por lo tanto del proceso. El surge en un compresor centrifugo es definido como una dramatica caida de flujo y presion, incluyendo flujo inverso. Esto es siempre un significante disturbio del proceso. El surge continuo resulta en costosos paros de proceso y danos mecanicos. Para prevenir el surge y controlar la presion de descarga con controles simples u obsoletos, es necesario ventear aire a la atmosfera. Esta forma de control es muy ineficiente y costosa. Un control avanzado con tecnologia de punta ademas de proveer valor economico previniendo danos por surge, provee sustanciales ahorros de energia reduciendo o eliminando el venteo de aire a la atmosfera.

  5. Experimental Research of Variable Operating Performance on Water Source Multi-Connected Air-Conditioning System with Digital Scroll Compressor

    Directory of Open Access Journals (Sweden)

    Xingwang Zhu


    Full Text Available In this study, we study the water source heat pump and digital scroll compressor and experimentally in the multi-connected air-conditioning system. Variable performance is developed when the unit operates in refrigerating and heating mode. The maximum of refrigerating capacity is 36519.95W when inlet water temperature of the condenser is 30°C and dry-bulb temperature of indoor air is 32°C, at the same time the maximum of EER is 4.33 when inlet water temperature of the condenser is 20°C and dry-bulb temperature of indoor air is 27°C. The unit operates in heating mode, the maximum of heating capacity and EER is 33275.73W and 3.86 when inlet water temperature of the condenser is 30°C and dry-bulb temperature of indoor air is 20°C.

  6. Intelligent Control of Air Compressor Unit Volume%空压机组气量调节的智能控制

    Institute of Scientific and Technical Information of China (English)



    Air compressor is one of the important equipment in cement plant whose power consumption is very large and has a long running time, so it is of vital importance to optimize working condition of air compressor unit. In view of the air compressor unit in cement factory, a kind of new intelligent control method of gas regulation was designed, which can achieve a wide range of automatic stepless adjustment of the air compressor unit displacement according to the user's actual air demand, ensure the compressor system pipe network pressure and make full use of the stability of the displacement.%空压机是水泥厂的主要耗电设备之一,其运行时间长,耗电量大,故对空压机组进行工况优化是至关重要的。针对水泥厂空压机组,设计出一种新的气量调节的智能控制方法,使空压机组的排气量能根据用户的实际需气量实现大范围的自动无级调节,保证压缩机组排气量的充分利用和系统管网压力稳定。

  7. Analysis on the Method to Start the Compressor of Inverter Air Conditioner%家用变频空调压缩机启动的浅析

    Institute of Scientific and Technical Information of China (English)

    李庆坚; 温得贤; 黄敬雁


    介绍并分析了目前行业内常用的压缩机启动方法,针对家用变频空调系统中压缩机在各负载工况下可能因启动力矩不足,而发生压缩机启动失败这一问题,通过对各品牌变频空调压缩机启动波形的分析以及实际的启动效果,得出一种较典型的压缩机启动方式。%This paper introduces and analyzes the common start methods of compressor in the industry. It is difficult to start the compressor of inverter air conditioner when the compressor is in harsh conditions. In this situation,it may put the compressor fail to start. Through the analysis of various brands of compressors of inverter air conditioners’start waveform, a typical starting mode of compressor is obtained.

  8. Experimental Study on the Waste Heat Utilization of Air Compressor in Coal Mine%煤矿空压机废热利用实验研究

    Institute of Scientific and Technical Information of China (English)

    王建学; 牛永胜; 袁静


    针对目前空压机排风废热的回收利用存在的问题,设计了采用热泵技术对空压机废热的回收方案。分析了空压机废热源热泵系统的工作原理,并建立了实验台进行实验研究,测试了不同的空压机排风温度、热水出水温度等因素对空压机废热源热泵系统性能的影响。通过对空压机废热源热泵系统在山西某煤矿的应用的举例,分析了煤矿空压机废热利用可收获的经济效益和社会效益。%Aiming at the current problems for the recycling and utilization of air compressor exhaust waste heat,it designed the recycling plan of air compressor waste heat with heat pump technology.The working principle of the heat pump system of air compressor waste heat source was analyzed,and the experiment table was established to do experimental research,test factors such as different air compressor exhaust temperature,outlet temperature of hot water which influence on the performance of the heat pump system.Through the exemplifying of the air compressor waste heat source heat pump system application to a coal mine in Shanxi province,it analyzed the economic benefit and social benefit which could be obtained by the air compressor waste heat utilization in the coal mine.

  9. Auto-ignition of lubricating oil working at high pressures in a compressor for an air conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chul Jin; Choi, Hyo Hyun [Department of Mechanical Engineering, Sejong University, Seoul 143-747 (Korea, Republic of); Sohn, Chae Hoon, E-mail: [Department of Mechanical Engineering, Sejong University, Seoul 143-747 (Korea, Republic of)


    Auto-ignition of lubricating oil working in a compressor for an air conditioner is studied experimentally. The adopted lubricating oil is an unknown mixture with multi-components and known to have flash point temperature of 170 deg. C. First, its auto-ignition temperature is measured 365 deg. C at atmospheric pressure. The lubricating oil works under high-pressure condition up to 30 atm and it is heated and cooled down repeatedly. Accordingly, auto-ignition temperatures or flammable limits of lubricating oil are required at high pressures with respect to fire safety. Because there is not a standard test method for the purpose, a new ignition-test method is proposed in this study and thereby, auto-ignition temperatures are measured over the pressure range below 30 atm. The measured temperatures range from 215 deg. C to 255 deg. C and they strongly depend on pressure of gas mixture consisting of oil vapor, nitrogen, and oxygen. They are close to flash point temperature and the lubricating oil can be hazardous when it works for high-pressure operating condition and abundant air flows into a compressor.

  10. Improvement on the control system for air compressor groups%LNG接收站空压机组联控系统的改进措施

    Institute of Scientific and Technical Information of China (English)

    张水红; 刘召


    Based on the pressure wave characteristics of air pipe networks in Jiangsu LNG Receiving Terminal, the operation characteristics and existing problems in air compressor system under the present control system is analyzed. According a matching for the actual air consumption and the air generation, it is concluded that the generation of single air compressor is enough to meet the requirements of the terminal. So, the improvement on the control system is put forward. The running mode of air compressor with two hosts and a backup machine is changed to a mode with one host and the first backup machine and the second backup machine. The normal value of air supply pressure, the lowest air pressure and the maximum air pressure are set for the system. An interlock between the drier and the air compressor is set to reduce the air consumption of the drier while the air compressor is unloaded. After the improvement, the air compressor is no longer loading and unloading frequently. The PSA nitrogen generation is increased and the oxygen content is reduced with a smooth running. Stably running of compressor reduces the current and mechanical shocks as well as the damages in intake and solenoid valves of air compressor by frequent loading change of the compressor, so the service life of the air compressor is extended. Electric energy is saved since the idle time is reduced. The pressure of compressed air pipeline networks tends to stabilization, and the operation of LNG receiving terminal is safer.%通过研究江苏LNG接收站压缩空气管网压力波动特性曲线,分析了在当前控制方式下空压机系统的运行特点及存在的问题.提出空压机组联控系统改进措施:将空压机运行模式由两主机一备机改为一主机、第一备机及第二备机,设定了系统正常供气压力、最低供气压力及最高供气压力;为减少空压机卸载时干燥机再生消耗,设置干燥机与空压机联锁.实践证明:联控系

  11. A Comparison of Two Air Compressors for PEM Fuel Cell Systems


    Kulp, Galen W.


    Proton exchange membrane (PEM) fuel cells are considered one of the best potential alternative power sources for automobiles. For this application, high efficiency and high power density are required. Pressurizing the fuel cell system can give higher efficiency, higher power density and better water balance characteristics for the fuel cell, but pressurization uses a percentage of the fuel cell output power. The compressor used to elevate the pressure has a direct effect on the system effi...

  12. Mid-section of a can-annular gas turbine engine with an improved rotation of air flow from the compressor to the turbine

    Energy Technology Data Exchange (ETDEWEB)

    Little, David A.; Schilp, Reinhard; Ross, Christopher W.


    A midframe portion (313) of a gas turbine engine (310) is presented and includes a compressor section with a last stage blade to orient an air flow (311) at a first angle (372). The midframe portion (313) further includes a turbine section with a first stage blade to receive the air flow (311) oriented at a second angle (374). The midframe portion (313) further includes a manifold (314) to directly couple the air flow (311) from the compressor section to a combustor head (318) upstream of the turbine section. The combustor head (318) introduces an offset angle in the air flow (311) from the first angle (372) to the second angle (374) to discharge the air flow (311) from the combustor head (318) at the second angle (374). While introducing the offset angle, the combustor head (318) at least maintains or augments the first angle (372).

  13. 船用重负荷空气压缩机油的研究%Research on Marine Severe Air Compressor Oil

    Institute of Scientific and Technical Information of China (English)

    岳国良; 冯全科


    A severe air compressor oil was developed with naphthenic oil and synthetic ester as base Stock added appropriate antioxidants,metal deactivators and rust inhibitors.The physicochemical properties of this air compressor oil reached to the level of DAB air compressor oil of ISO 6743-3∶2003 “air compressor oil”specifica-tion,and the carbon deposits tendency rig test was passed.%用环烷基油和合成酯为基础油,并加入适量抗氧剂,金属钝化剂和防锈剂,研制了一种重负荷空气压缩机油。该油的理化性能到达了ISO 6743-3∶2003《空气压缩机油》规格中DAB空气压缩机油的水平,并通过了积炭倾向台架试验。

  14. Improvement and Application of Reciprocating Air Compressor%浅谈往复式空压机的改进及运用

    Institute of Scientific and Technical Information of China (English)



    he importance of GuiYe diesel generator room reciprocating air compressor to successfully restart diesel engine during the accidents in power workshop is introduced. The problems and structure principle of reciprocating air compressor before the improve-ment are analyzed. The reciprocating air compressor gradually improved after practice, the success of the diesel engine is started for the accident, the operation of the reciprocating compressor efficiency, saving energy and reducing consumption, safety and environmental improvement are expounded in this article.%介绍贵冶动力车间事故柴油发电机房往复式空压机对全厂停电时柴油机能否成功启动的重要性,对改进前往复式空压机所存在的问题及结构原理进行分析。阐述了通过对往复式空压机逐步改进实践后,对事故柴油机的成功启动、往复式空压机的运行效率、节能降耗、安全环保等方面带来的改善。

  15. Investigation of the compressor part-load behaviour and its effects on the per annum energy consumption of the air conditioner; Untersuchung des Kompressor-Teillastverhaltens im Hinblick auf den Jahresverbrauch der Klimaanlage

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Klaus; Lechner, Bernhard [Virtual Vehicle. Kompetenzzentrum - Das virtuelle Fahrzeug Forschungsgesellschaft mbH (ViF), Graz (Austria); Rieberer, Rene [Technische Univ. Graz (Austria); Moenkediek, Thomas [Audi AG, Ingolstadt (Germany)


    The air conditioning system is one of the most important ancillary units of a motor vehicle. Energetic optimization of air conditioners has been a key issue of research at AUDI AG during the past few years. As a rule, the cooling capacity of the air conditioner is controlled by adapting the compressor lift if the compressor is driven by the car engine and control via the rotational speed is not possible. As air conditioners ted to be designed for extreme conditions, the compressor will work at part load in most operating conditions. Optimization of the energetic efficiency of the air conditioner also means to look at the part-load behaviour of the compressor. Simulations have been used successfully by AUDI AG for many years now; the have helped to shorten development times and improve the product quality. The contribution describes an advanced model of a swivel plate compressor of a R134a cooling cycle with particular consideration of part-lift operation. The simulation model is based on measurements with continous recording of the piston lift. The focus is on the influence of reduced lift on the compressor efficiency. Another point of interest is the successful integration of the compressor model in the overall refrigerating cycle model which will be used for simulations of system performance and efficiency and for further optimization of the air conditioner. (orig.)

  16. Numerical simulation of axial flow compressors.


    Jesuino Takachi Tomita


    This work deals with the numerical simulation of axial flow compressors, from design to performance prediction. The stage performance prediction uses the meanline flow properties. Stage-stacking is used to analyse a multi-stage compressor. A computer program, written in FORTRAN, was developed and is able to design an axial flow compressor given air mass flow, total pressure ratio, overall efficiency and design speed. All geometrical data relevant to the compressor performance prediction is ca...

  17. Reason Analysis and Countermeasures on One Attempted Air Compressor Accident%一起空压机未遂事故原因解析与对策

    Institute of Scientific and Technical Information of China (English)

    李宗白; 梁友乾


    The paper analyzes and solves start-up failure of air compressor incurred by excitation time lagging of synchronous motor, and potential operation safety hazard caused by equipment manufacturing and installation quality, meanwhile, the paper puts forward countermeasures on electrical design, installation and operation of air compressor.%分析解决了空气压缩机因直连拖动同步电动机投励时间滞后引起的启动失败故障,以及设备制造、安装质量造成的运行安全隐患,提出了空压机电气设计、安装与运行安全对策措施。

  18. 空气压缩机余热回收的实践%Practice of Waste Heat Recovery from Air Compressors

    Institute of Scientific and Technical Information of China (English)

    王佩; 成强


    介绍了空气压缩机余热回收系统的工作原理和节能效果,为相关技术人员提供参考,从而达到节能的目的。%This article introduces working principle and energy saving effect of waste heat recovery system of air compressors. It gives references to technological staff to achieve energy saving.

  19. Exergetic analysis of a double stage LiBr-H{sub 2}O thermal compressor cooled by air/water and driven by low grade heat

    Energy Technology Data Exchange (ETDEWEB)

    Izquierdo, M. [Instituto C.C. Eduardo Torroja (CSIC), Edificacion y Habitabilidad, Madrid (Spain); Venegas, M.; Garcia, N. [Universidad Carlos III de Madrid (Spain). Departamento de Ingenieria Termica y Fluidos; Palacios, E. [Universidad Politecnica de Madrid (Spain). Departamento de Mecanica Industrial


    In the present paper, an exergetic analysis of a double stage thermal compressor using the lithium bromide-water solution is performed. The double stage system considered allows obtaining evaporation temperatures equal to 5{sup o} C using solar heat coming from flat plate collectors and other low grade thermal sources. In this study, ambient air and water are alternatively used as cooling fluids without crystallization problems up to condensation-absorption temperatures equal to 50 {sup o}C. The results obtained give the entropy generated, the exergy destroyed and the exergetic efficiency of the double stage thermal compressor as a function of the absorption temperature. The conclusions obtained show that the irreversibilities generated by the double stage thermal compressor will tend to increase with the absorption temperature up to 45 {sup o}C. The maximum value corresponds to 1.35 kJ kg{sup -}1{sup K-1}. The entropy generated and the exergy destroyed by the air cooled system are higher than those by the water cooled one. The difference between the values increases when the absorption temperature increases. For an absorption temperature equal to 50 {sup o}C, the air cooled mode generates 14% more entropy and destroys 14% more exergy than the water cooled one. Also, the results are compared with those of previous studies for single and double effect air cooled and water cooled thermal compressors. The conclusions show that the double stage system has about 22% less exergetic efficiency than the single effect one and 32% less exergetic efficiency than the double effect one. (author)

  20. 基于Zigbee的工厂空压站监控系统设计%Zigbee-based factory air compressor station monitor and control system design

    Institute of Scientific and Technical Information of China (English)

    姚仲敏; 李魁杰; 张裕; 潘飞


    To solve the problems of current electrical control system of air compressor station, this paper presents a zigbee-based air compressor station monitor and control system. The air compressors effective management is the foundation of the whole control system, as the control of all electrical actuators, inverters and motors is achieved through PLC. The system uses the pressure sensors and flow sensors to collect data from the air compressor network, by means of the Zigbee technology to transmit data, and apply Labview control software for the monitor and control center host computer. Meanwhile, the joints of ZigBee have low power consumption and high flexibility, easy for networking and maintenance.%针对目前的空压站电气控制系统存在的问题,提出了一种基于无线传感网的空压站监控系统。空压机组的有效管理是整个控制系统的基础,通过PLC实现对电气各执行器、变频器、电机等进行控制;利用压力传感器、流量传感器采集空压管网数据,并应用ZigBee技术进行数据传输;采用Labview设计监控中心上位机控制软件;同时ZigBee节点的低功耗和灵活性的特点,方便组网和维护。

  1. Frequency inverter energy saving reconstruction of screw air compressor%螺杆式空压机变频节能改造方案设计

    Institute of Scientific and Technical Information of China (English)

    吕新磊; 王永华; 高永田


    针对螺杆式空压机能耗大、噪音大、自动化程度低等问题,在螺杆式空压机节能原理的基础上,提出了利用变频器对螺杆式空压机进行节能改造的方案.该方案采用安全连锁、PID调节和电机温升控制等技术手段来实现.节能效果分析表明,该方案节电率达到28.3%,具有推广价值.%Aiming at the shortcomings of screw air compressor such as high energy consumption, big noise and low automation level etc, on the basis of the principle of screw air compressor energy-saving, a reforming scheme to save energy of screw air compressor by using frequency inverter was provided. The techniques such as safety chain PID adjustment and motor temperature rising control werer applied in the reforming scheme. Energy saving effect results showed that the energy saving rate reached up to 28. 3%. Reforming scheme has large value to be popularized.

  2. Experimental investigation on a turbine compressor for air supply system of a fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Masayasu [Sumitomo Heavy Industries, Ltd., Yokosuka (Japan); Tsuchiyama, Syozo [Shipbuilding Research Association, Minato-ku, Tokyo (Japan)


    This report covers part of a joint study on a PEFC propulsion system for surface ships, summarized in a presentation to this Seminar, entitled {open_quotes}Study on a Polymer Electrolyte Fuel Cell (PEFC) Propulsion System for Surface Ships{close_quotes}, and which envisages application to a 1,500 DWT cargo vessel. The aspect treated here concerns a study on the air supply system for the PEFC, with particular reference to system components.

  3. Application of Air Compressor System Waste Heat Recovery in Air-conditioning System%空气压缩机系统余热回收在空调系统中的应用

    Institute of Scientific and Technical Information of China (English)



    对空气压缩机的压缩余热进行回收利用,可以降低压缩空气系统损耗,提高生产力,实现节能降耗.将空压机余热用于空调系统冬季采暖和生活热水供应,节能效果良好,经济效益明显,具有实用和推广价值.%Recovering the waste heat of air compressors, can lower the consumption of energy in compressed air system and increase productivity. Illustrates that the waste heat of air compressors can be successfully applied to the air-conditioning system in winter heating and used to warm the domestic water in the meanwhile. Moreover, the good energy-saving result and the obvious economical benefit both indicate that the waste heat recovery of air compressors will have a bright applied prospect.

  4. Research on Energy Efficiency Specific Gravity of Air Cooling System for Oil Injection Screw Air Compressor%喷油螺杆空压机风冷却系统能效比重研究

    Institute of Scientific and Technical Information of China (English)

    谭强; 沈坤华; 肖银娥; 朱海峰; 郑鹏程; 章正峰


    根据当前螺杆空压机能效标准和产品标准的规定,结合螺杆空压机实际应用的具体条件,依据物质能量守恒定律,推导出螺杆空压机风冷却系统能效比重的计算公式,得出具体的计算结果,供风冷却螺杆空压机设计、节能管理、标准化工作者参考.%According to the specifications of current energy and product standards for screw compressor,combined with the concrete conditions of practical application of screw compressor,the calculating formula for energy efficiency specific gravity of air cooling system for screw compressor is deduced and the concrete calculating results are obtained based on law of energy conservation,which provides references for design,energy-saving management and standardization staff of air cooling screw compressor.

  5. 小型空气压缩机电机的断相保护%The Phase_broken Protection of Small_scale Air Compressor Motor

    Institute of Scientific and Technical Information of China (English)



    This paper introduces the method of phase_broken protection for small_scale air compressor motor.The phase_broken protection cir cuit is given.The operation principle of phase_broken protection circuit is ana lyzed in detail%介绍了小型空气压缩机电机的断相保护方法,给出 了断相保护电路,详细分析了断相保护电路的工作原理。

  6. Air conditioning in a CINEMAXX cinema. Innovative solution involving a screw compressor and direct evaporation; Klimatisierung in einem CINEMAXX-Kino. Innovative Loesung mit Schraubenverdichter und Direktverdampfung

    Energy Technology Data Exchange (ETDEWEB)



    The new CINEMAXX cinema building in the Trier city centre has fully glazed walls and a modern air conditioning system. The system was installed by local organisations. Its key components are two Comer-Dorin screw compressors. [German] Im Trierer Stadtzentrum befindet sich ein neues CINEMAXX-Kino, hinter dessen glaeserner Fassade die Klimaanlage diskret verborgen bleibt. Oertliche Firmen der Branche konnten die Ausschreibung der Klimaanlage zu ihren Gunsten entscheiden und mit Erfahrung und handwerklichem Koennen unter Verwendung zweier Comer-Dorin-Schraubenverdichter eine nachahmenswerte Loesung planen und installieren. (orig.)

  7. Waste Heat Recovery and Energy Efficient Analysis of Screw Air Compressors%螺杆式空压机余热回收及节能分析

    Institute of Scientific and Technical Information of China (English)



    介绍了螺杆式空气压缩机的余热回收,着重分析了余热回收的意义,节能计算、节能空间和市场前景。并以某厂为例,进行了实际的节能计算。%waste heat recovery of screw air compressor is Introduced,four aspects of waste heat recovery are emphatically analyzed,including significance,energy-efficient computing energy space and market prospect.Take a factory as an example,energy-efficient is computed.

  8. Design of Monitoring System for Air Compressors Based on LabVIEW%基于LabVIEW的压风机组监控系统设计

    Institute of Scientific and Technical Information of China (English)

    李高磊; 郑晓亮


    Mainly research the monitoring system for mine air compressors ,with the base of the analysis of characteristics of the existing unit air compressors on the basis of the monitoring system, a compressed air unit online monitoring system based on LabVIEW has been set up. The system consists of sensors, signal acquisition card, PLC, inverter and PC monitor screen. Realization of the state unit of the wind pressure parameters real-time online acquisition, real-time control, storage, display and warning, and rely on DataSocket technology enables remote monitoring.%以煤矿压风机组监控系统为研究对象,在分析现有压风机组监控系统特点的基础上,搭建了基于LabVIEW的压风机组在线监控系统。该系统包括传感器、信号采集卡、PLC、变频器和上位机监控界面。实现了对压风机组的状态参数的实时在线采集、实时控制、存储、显示与预警,并依靠DataSocket技术实现了远程监控。

  9. NG compressors play role in success story

    Energy Technology Data Exchange (ETDEWEB)



    In early 1993, Con Edison and Brooklyn Union Gas began offering rebates to manufacturers that replaced electric motor-driven air compressors with natural gas engine-driven air compressors. These rebates covered significant portions of the costs of installation. After carefully considering all options, Ultra Creative decided to order two Quincy QSS-750-NG, 220-HP units from scales Air Compressor Crop. Scales is a full-service air compressor distribution which offers complete turnkey installation service on all types of stationary air compressors, plus maintenance and repairs. The complete Quincy QSS Series of natural gas engine-driven air compressors is available in sizes from 370 to 1500 cfm. An optical heat recovery system can boost energy efficiencies over 80%. For example, heat recovered from the engine cooling water and exhaust, combined with the heat recovered from the air compressor oil cooler and aftercooler, can be used for heating boiler and laundry process water, plastics thermoforming, unit heaters for space heating, plating tanks, and a variety of other applications to displace conventional fuels.

  10. Development of Protection System Preventing 60 000 m3 Air Compressor from Stall%60000m3空压机喘振保护系统的研发

    Institute of Scientific and Technical Information of China (English)



    This article describes the reason and harm of air compressor stall in detail ,and elaborates the principle of the anti-stall control system .A protection system for 60 000 m3 air compressor is set up .By using the function of DCS and PLC ,we can make the control of compressor fast and reliable .This work has important reference value to the other anti-stall control systems .%简述了喘振的原理及危害。详细阐述了防喘振系统的控制原理,并建立了60000 m3空压机的保护系统,利用DCS和PLC的强大功能实现快速可靠的控制,对其他系统的防喘振控制有着重要的参考价值。

  11. YC12系列空压机升程吸气限制器的加工工艺改装%The Refitting of Processing Technic of YC12 Series Air-compressor Lift Air Induction Limiter

    Institute of Scientific and Technical Information of China (English)

    杨宗斌; 况齐祁; 余新华


    YC12系列空压机限制其转速提高的关键问题之一就是气阀,它是易损坏部件.升程吸气限制器是整套阀组的核心,直接影响压缩机的排气量、功率消耗及运转的可靠性.就生产中采用的刀具和工装进行改进作介绍,提高了气阀加工效率,降低生产成本的一种新技术.%One of the key problems of limiting the improvement of the revolution of YC12 series air-compressor is the air valve,which is apt to damage.Among them,lift air induction limiter is the key part of whole set valve hank,which directly influences the air discharge of compressor,power dissipation and the reliability of operation.This paper intends to introduce a new technology which improved the cutter and frock ,enhanced the efficiency of air valve processing and lowered the production cost.

  12. Air-source heat pump coupled with economized vapor injection scroll compressor and ejector:Design and experimental research

    Institute of Scientific and Technical Information of China (English)


    Ejector can utilize high pressure energy from liquid mechanism,it can be used in heat pump system coupled with economized vapor injection(EVI)scroll compressor.When running under low temperature conditions,the performance of the EVI system with ejector can be improved further.In this paper,the design method of the heat pump system with ejector is presented,and the process for designing the heat pump with ejector(EVIe)was summarized.One prototype heat pump was designed under the condition of the evaporation temperature of -20oC,and an experimental setup was established to test the prototype.The measured results demonstrated that the heating EER(energy efficiency ratio)of the EVIe could reach about 4%higher than that of the system without the ejector when the heating capacity remained nearly constant.The design method is helpful to development of a heat pump system coupled with scroll compressor and ejector.

  13. Supersonic compressor (United States)

    Roberts, II, William Byron; Lawlor, Shawn P.; Breidenthal, Robert E.


    A supersonic compressor including a rotor to deliver a gas at supersonic conditions to a diffuser. The diffuser includes a plurality of aerodynamic ducts that have converging and diverging portions, for deceleration of gas to subsonic conditions and then for expansion of subsonic gas, to change kinetic energy of the gas to static pressure. The aerodynamic ducts include vortex generating structures for controlling boundary layer, and structures for changing the effective contraction ratio to enable starting even when the aerodynamic ducts are designed for high pressure ratios, and structures for boundary layer control. In an embodiment, aerodynamic ducts are provided having an aspect ratio of in excess of two to one, when viewed in cross-section orthogonal to flow direction at an entrance to the aerodynamic duct.

  14. OMC Compressor Case (United States)

    Humphrey, W. Donald


    This report summarizes efforts expended in the development of an all-composite compressor case. Two pre-production units have been built, one utilizing V-CAP and one utilizing AFR-700B resin systems. Both units have been rig tested at elevated temperatures well above design limit loads. This report discusses the manufacturing processes, test results, and Finite Element Analysis performed. The V-CAP unit was funded by NASA-Lewis Research Center in 1994 under contract number NAS3- 27442 for Development of an All-Composite OMC Compressor Case. This contract was followed by an Air Force study in 1996 to build and identical unit using the AFR-700B resin system in place of the V-CAP system. The second compressor case was funded under U.S. Air Force contract F33615-93-D-5326, Advanced Materials for Aerospace Structures Special Studies (AMAS3), Delivery Order 0021 entitled "Advanced Polymeric Composite Materials and Structures Technology for Advanced High Temperature Gas Turbine Engines.' Initial studies using the V-CAP resin system were undertaken in 1993 under a NASA Lewis contract (NAS3-26829). A first prototype unit was developed in a joint program between Textron-Lycoming (now Allied Signal) and Brunswick (now Lincoln Composites). This unit included composite end closures using low density, high temperature molded end closures. The units was similar in size and shape to a titanium case currently used on the PT-21 0 engine and was funded as part of the integrated High Performance Turbine Engine Technology (EHPTET) initiative of DOD and NASA.

  15. 双变频压缩机并联系统及其在多联机上的应用%The System With Two Parallel Connected Variable Speed Compressors and Its Application on Multiple-split Air-conditioner

    Institute of Scientific and Technical Information of China (English)



    The system with two parallel connected variable speed compressors is a new air-conditioner system which has two variable speed compressors in a outdoor unit instead of one inverter compressor. Through theory analyzing and testing, we prove that this system is more efficient than the traditional system with one variable speed compressor, especially on multiple-split air-conditioner whose load is variable.%双变频压缩机并联系统是通过使用两台小排气量的变频压缩机代替传统的单变频压缩机的一种新型空调系统。经理论分析及试验验证,双变频压缩机并联系统应用于负荷变化大的多联机组时比传统的单压缩机系统能效优势明显。

  16. The System with Two Parallel Connected Variable Speed Compressors and Its Application on Multiple-split Air-conditioner%双变频压缩机并联系统及其在多联机上的应用

    Institute of Scientific and Technical Information of China (English)



    双变频压缩机并联系统是通过使用两台小排气量的变频压缩机代替传统的单变频压缩机的一种新型的空调系统。经理论分析及试验验证,双变频压缩机并联系统应用于负荷变化大的多联机组,比传统的单压缩机系统能效优势明显。%The system with two parallel connected variable speed compressors is a new air-conditioner system which has two variable speed compressors in a outdoor unit instead of one inverter compressor. Through theory analyzing and testing, we proved that this system is more efficient than the traditional system with one variable speed compressor, es-pecially on multiple-split air-conditioner whose load is variable.

  17. Case Study regarding the test of the new screw compressor with high delivery pressure - 45 bara - on the test bench (with air

    Directory of Open Access Journals (Sweden)

    Valentin PETRESCU


    Full Text Available Screw compressors, which are part of positive displacement compressors, can find an increasing use in gas industry and beyond due to their advantages. Maximal parameters of these devices, done by Comoti under GHH-Rand license stop at a maximum flow of 3000 Nm3/hour and 26 bara discharge pressure. The needs of potential beneficiaries have imposed the necessity to design and manufacture a new family of screw compressors and oil injection able to develop a discharge pressure of 45 bara with flow rates up to 5000 Nm3/hour. This paper presents the design and experimental test phases – for the first screw compressor with discharge of pressure up to 45 bara – CU90 HP. Continue research and development have allowed to this type of screw-compressor – to find a market position, diversifying its size range in the last decade in a manner more explosive, if we refer to other types of compressors.

  18. Development of ZL400 Mine Cooling Unit Using Semi-Hermetic Screw Compressor and Its Application on Local Air Conditioning in Underground Long-Wall Face (United States)

    Chu, Zhaoxiang; Ji, Jianhu; Zhang, Xijun; Yan, Hongyuan; Dong, Haomin; Liu, Junjie


    Aiming at heat injuries occurring in the process of deep coal mining in China, a ZL400 mine-cooling unit employing semi-hermetic screw compressor with a cooling capacity of 400 kW is developed. This paper introduced its operating principle, structural characteristics and technical indexes. By using the self-built testing platform, some parameters for indication of its operation conditions were tested on the ground. The results show that the aforementioned cooling unit is stable in operation: cooling capacity of the unit was 420 kW underground-test conditions, while its COP (coefficient of performance) reached 3.4. To address the issue of heat injuries existing in No. 16305 U-shaped long-wall ventilation face of Jining No. 3 coal mine, a local air conditioning system was developed with ZL400 cooling unit as the system's core. The paper presented an analysis of characteristics of the air current flowing in the air-mixing and cooling mode of ZL400 cooling unit used in air intake way. Through i-d patterns we described the process of the airflow treatment, such as cooling, mixing and heating, etc. The cooling system decreased dry bulb temperature on working face by 3°C on average and 3.8°C at most, while lowered the web bulb temperature by 3.6°C on average and 4.8°C at most. At the same time, it reduced relative humidity by 5% on average and 8.6% at most. The field application of the ZL400 cooling unit had gain certain effects in air conditioning and provided support for the solution of mine heat injuries in China in terms of technology and equipment.

  19. Air cooled heat pumps with mono-screw compressors. A good alternative; Luchtgekoelde warmtepompen met mono-schroefcompressoren. Een goed alternatief

    Energy Technology Data Exchange (ETDEWEB)

    Meijer, W. [Daikin Airconditioning Netherlands, Rotterdam (Netherlands)


    Heat pumps are becoming increasingly popular. Often water/water heat pumps are used that are linked to heat/cold storage systems or another source system. The air-cooled alternatives are advancing in house construction and are also applied in small-scale utility and schools sometimes. In the larger utility projects and the industry, however, the air-cooled heat pump has not quite yet found its way, while it can be a good alternative for the heat/cold storage systems that are much more expensive to purchase. This is due to new compressor techniques. [Dutch] Warmtepompen worden steeds populairder. Veelal wordt gebruikgemaakt van water/water-warmtepompen, die gekoppeld worden aan een koude/warmte-opslagsysteem (KWO) of ander bronsysteem. De luchtgekoelde alternatieven zijn in de woningbouw in opmars en worden soms ook in kleinschalige utiliteit en scholen toegepast. In de grotere utiliteitsprojecten en industrie heeft de luchtgekoelde warmtepomp echter zijn weg nog niet echt gevonden, terwijl het een goed alternatief kan zijn voor de in aanschaf veel duurdere KWO-systemen. Dit mede dankzij nieuwe compressortechnieken.


    Directory of Open Access Journals (Sweden)

    Gulyaev P. V.


    Full Text Available The article is devoted to the development of a compressor type ozonator. It describes the design of a high-productivity compressor ozone generator, which can be used for industrial decontamination of mixed feeds, water, milk, and in the system of presowing treatment of seeds. This construction allows generating ozone with high concentration to 5 g/m3 at high feed air or oxygen from the compressor station (up to 2000 l/min. The article describes the design of the basic elements of tubular ozone generator, examines the factors influencing the productivity of the ozonator. The proposed mathematical model allows calculating the productivity of the ozonator when considering multiple influencing factors. These factors take into account: the parameters of supply voltage, such as the magnitude and frequency of the supply voltage; the configuration and geometrical parameters of electrodes such as, the area of the electrodes, the configuration of the surface of the electrodes and distance between electrodes; parameters dielectric barrier; and the transported gas parameters such as volume, temperature, pressure and composition. Special attention is paid to the design of the electrodes made of woven wire mesh with mesh sizes from 1.5×1.5 to 2.0×2.0 mm. It is noted, that such electrodes allow obtaining the maximum productivity of an ozonator, and they do not lead to overheating of the dielectric barrier, and do not output down the generator. In the same way, the article presents the results of the mathematical modeling of ozone generator productivity while changing various factors

  1. Research Status of the Noise in Rotary Air Conditioner Compressor for Automotive%车用旋转式空调压缩机噪声研究现状

    Institute of Scientific and Technical Information of China (English)

    邹杨; 叶禾; 杨诚


    旋转式空调压缩机的噪声直接影响空调系统舒适性,回顾了旋转式压缩机噪声的国内外研究现状,对旋转式压缩机的噪声进行分类评述,最后讨论了目前研究存在的问题并对未来的研究做了展望.%The noise of rotary air conditioner compressor directly affects the comfort of air conditioning systems, this paper reviews the recent study at home and abroad which about the rotary compressor noise,classifies comments about those noises,and finally discusses the problems of current research and makes prospects for futher research.

  2. Refrigeration system having dual suction port compressor (United States)

    Wu, Guolian


    A cooling system for appliances, air conditioners, and other spaces includes a compressor, and a condenser that receives refrigerant from the compressor. The system also includes an evaporator that receives refrigerant from the condenser. Refrigerant received from the condenser flows through an upstream portion of the evaporator. A first portion of the refrigerant flows to the compressor without passing through a downstream portion of the evaporator, and a second portion of the refrigerant from the upstream portion of the condenser flows through the downstream portion of the evaporator after passing through the upstream portion of the evaporator. The second portion of the refrigerant flows to the compressor after passing through the downstream portion of the evaporator. The refrigeration system may be configured to cool an appliance such as a refrigerator and/or freezer, or it may be utilized in air conditioners for buildings, motor vehicles, or other such spaces.

  3. Miniature Centrifugal Compressor (United States)

    Sixsmith, Herbert


    Miniature turbocompressor designed for reliability and long life. Cryogenic system includes compressor, turboexpander, and heat exchanger provides 5 W of refrigeration at 70 K from 150 W input power. Design speed of machine 510,000 rpm. Compressor has gas-lubricated journal bearings and magnetic thrust bearing. When compressor runs no bearing contact and no wear.

  4. Coatings for Fuel Cell Propulsion Compressor Bearings Project (United States)

    National Aeronautics and Space Administration — Fuel cell air handling systems require clean and contaminant-free inlet air, which dictates that oil-free, motorized, compressor/expander systems should be used....

  5. A Novel Vapor Injection Structure on the Blade for Rotary Compressor


    Wang, Baolong; Liu, Xingru; Shi, Wenxing


    Rotary compressors have been extensively used in room air conditioners and household refrigerators for their advantages, including high efficiency, strong adaptability, and low cost. However, when air source heat pumps with rotary compressors are applied in cold regions, a series of problems appear. The gas injection has been proved an effective technology to enhance both the heating capacity and COP of scroll, screw, and rotary compressors. In the one-cylinder rotary compressor with gas in...

  6. 基于IMFAC的空压机出口压力控制%Air Compressor Outlet Pressure Control Based on IMFAC

    Institute of Scientific and Technical Information of China (English)

    屠袁飞; 高翀


    以南京某石化企业的空分设备为背景,根据空压机非线性、时变、大时滞等特点,使用了一种改进的无模型自适应控制( IMFAC),设计IMFAC-PID串级控制方案,并利用MATLAB/Simulink进行仿真。仿真结果证明,IMFAC具有调节时间短、超调量小、响应速度快等特点。与基本无模型自适应控制和PID控制相比,使用IMFAC-PID的系统具有更好的鲁棒性、更快的响应速度和更高的稳态精度。%In the context of air separation plant of a petrochemical enterprise in Nanjing,based on the air compressor has the characteristics of nonlinear,time-varying and large time delay,an improved model-free adaptive control ( IMFAC) was used,the IMFAC-PID cascade control scheme was designed and a simulation was carried out by adopting Matlab simulation software. The simulation result shows that improved model-free adaptive control has shorter setting time, less overshoot and higher response speed.Compared with the basic model-free adaptive control and PID control,the system has better robustness,higher response speed and steady-state accuracy using IMFAC-PID.

  7. 便携式无油润滑空压机冷却系统布局探讨%Discussion about the Layout of Cooling System for a Portable Oil-free Lubricating Air Compressor

    Institute of Scientific and Technical Information of China (English)

    耿爱农; 李辛沫; 陈君立; 阮勤江


    The layout of cooling system for a portable oil-free lubricating air compressor with crankcase intaking was explored in this paper. Aimed at the compressor's weakness of the high working temperature of the crankcase bearing pedestal, a scheme of letting part of cooling air cross through the crankcase was adopted, which makes the temperature of bearing pedestal reduced about 4t compared with adopting traditional cooling way, and the working reliability of compressor main bearing was enhanced.%对某便携式曲轴箱进气无油润滑空压机冷却系统的布局进行了探索,针对该机曲轴箱轴承座温度较高的弱点,采用让部分冷却风横渡扫掠曲轴箱的冷却方案,使轴承座的温度较之采用传统冷却方式时的温度下降了大约4℃,由此提高了压缩机主轴承的工作可靠性.

  8. A Method to Predict Compressor Stall in the TF34-100 Turbofan Engine Utilizing Real-Time Performance Data (United States)


    preventive maintenance for the TF34-100 jet engine to prevent engine compressor stalls for the A-10 aircraft. Due to their destructive nature, compressor...stalls are a significant concern in axial flow compressor jet engines . A compressor stall is caused by air approaching the compressor blades at an...variables in an effort to gain a better understanding of the engine system. This would be a more comprehensive undertaking, and the complexity of work

  9. 4L-20/8空气压缩机智能化控制技术及应用实践%The Intelligent Control Technology and Practical Application of the 4L-20/8 Air Compressor

    Institute of Scientific and Technical Information of China (English)

    苏震; 刘秋杰


    The article analysis the 4L-20/8 air compressor operation condition,made the practical air and the compressed air dynamic matching,realized the motor speed stepless adjustment,stop the motor under no-load running,and made gas production as improved conditions for intelligent control of air compressors.Intelligent control method use the computer-controlled management system,using a set of intelligent control systems to drive multiple 4L-20/8 air compressor to achieve a drag and more control,and install a pressure sensor in the tank pressure pipe,then control the regulation of air compressors.The success of the intelligent control transformation of the 4L-20/8 air compressor system is very important and has a broad application prospect,which provides a new means for enterprises to save energy and improve economic efficiency for the type of energy to run the air compressor.%通过分析4L-20/8空气压缩机的运行工况,使用气量与压气量动态匹配,实现电动机转速无级调节,防止电动机在空载下运行,并将用产气量作为改进空气压缩机智能化控制的条件。智能化控制方法利用微机控制管理系统,用一套智能化控制系统驱动多台4L-20/8空气压缩机,进行一拖多控制,在储气罐的压力管道上安装压力传感器,实现对空气压缩机的控制与调节。通过对4L-20/8空气压缩机进行智能化控制,可以降低能源消耗,减少设备的维修保养工作量,从而实现空气压缩机无人值守自动运行。该系统改造的成功,为此类型空气压缩机的节能运行提供了新手段,对于企业节能降耗,提高企业经济效益有重要意义,有广阔的推广应用前景。

  10. Dual-worm screw compressors; Compresseurs bi-vis

    Energy Technology Data Exchange (ETDEWEB)

    Baleydier, J.P. [Bitzer France, 69 - Lyon (France)


    Low power worm-screw moto-compressors are used in any king of refrigerating machineries and more and more in air conditioning systems. This paper presents the principle of dual-screw moto-compressors: worm-screw technology, role of oil (lubrication, tightness, cooling), compression, internal pressure, power reduction, lubrication, economizer, operation, model selection and accessories. (J.S.)

  11. 转速可控型房间空调器用压缩机能效评价方法研究及应用%Analysis and Application of Evaluation Method on Compressors for Variable Speed Room Air Conditioners

    Institute of Scientific and Technical Information of China (English)

    张海锋; 吴建华; 厉彦忠


    The efficiency requirement of room air conditioner (RAC) has became stricter and stricter with the development of global environment consciousness. The efficiency evaluation method of RAC has been updated from single working condition to aunnal performance factor (APF) with multiple working condition. Performance evaluation method of compressors must be changed accordingly which account for main energy consumption of RAC. Compressor efficiency of annual performance (COAP) is proposed to evaluate the efficiency level of inverter compressor which is applied in variable speed RAC with multiple working conditions. Actual operation efficiency can be indicated by COAP because inverter compressor performance is considered according to COAP. In order to simplify test procedure of COAP, standard test conditions and its weight are generated .Then the effect of efficiency curve of inverter compressor on COAP is discussed . Finally examples with this method are illustrated for compressor matching and design optimization.%  随着全球环境保护意识的加强,家用空调能耗水平不断增高,房间空调器能效评价方法已从单工况向全年运行效率(APF)转变。压缩机作为空调器中的主要耗能部件,其能效评价方法也要随之变化。这里提出了变速压缩机全年综合能效比指标--COAP来衡量压缩机在全年变工况条件下的运行效率,此指标综合考虑了变速压缩机全年运行的能效情况,能客观反映压缩机在不同气候条件下实际运行效率。为简化测试COAP,给出了COAP基准工况及各工况权重,讨论了压缩机效率曲线对COAP的影响,最后通过举例说明如何利用COAP进行压缩机选型及设计优化。

  12. Compressors selection and sizing

    CERN Document Server

    Brown, Royce N


    This practical reference provides in-depth information required to understand and properly estimate compressor capabilities and to select the proper designs. Engineers and students will gain a thorough understanding of compression principles, equipment, applications, selection, sizing, installation, and maintenance. The many examples clearly illustrate key aspects to help readers understand the ""real world"" of compressor technology.Compressors: Selection and Sizing, third edition is completely updated with new API standards. Additions requested by readers include a new section on di

  13. Gravity Independent Compressor Project (United States)

    National Aeronautics and Space Administration — We propose to develop and demonstrate a small, gravity independent, vapor compression refrigeration system using a linear motor compressor which effectively...

  14. The New S-RAM Air Variable Compressor/Expander for Heat Pump and Waste Heat to Power Application

    Energy Technology Data Exchange (ETDEWEB)

    Dehoff, Ryan R [ORNL; Jestings, Lee [S-RAM Dynamics; Conde, Ricardo [S-RAM Dynamics


    S-RAM Dynamics (S-RAM) has designed an innovative heat pump system targeted for commercial and industrial applications. This new heat pump system is more efficient than anything currently on the market and utilizes air as the refrigerant instead of hydrofluorocarbon (HFC) refrigerants, leading to lower operating costs, minimal environmental costs or concerns, and lower maintenance costs. The heat pumps will be manufactured in the United States. This project was aimed at determining the feasibility of utilizing additive manufacturing to make the heat exchanger device for the new heat pump system. ORNL and S-RAM Dynamics collaborated on determining the prototype performance and subsequently printing of the prototype using additive manufacturing. Complex heat exchanger designs were fabricated using the Arcam electron beam melting (EBM) powder bed technology using Ti-6Al-4V material. An ultrasonic welding system was utilized in order to remove the powder from the small openings of the heat exchanger. The majority of powder in the small chambers was removed, however, the amount of powder remaining in the heat exchanger was a function of geometry. Therefore, only certain geometries of heat exchangers could be fabricated. SRAM Dynamics evaluated a preliminary heat exchanger design. Although the results of the additive manufacturing of the heat exchanger were not optimum, a less complex geometry was demonstrated. A sleeve valve was used as a demonstration piece, as engine designs from S-RAM Dynamics require the engine to have a very high density. Preliminary designs of this geometry were successfully fabricated using the EBM technology.


    Directory of Open Access Journals (Sweden)

    Adhimoulame Kalaisselvane


    Full Text Available Supercharging is a process which is used to improve the performance of an engine by increasing the specific power output whereas exhaust gas recirculation reduces the NOx produced by engine because of supercharging. In a conventional engine, supercharger functions as a compressor for the forced induction of the charge taking mechanical power from the engine crankshaft. In this study, supercharging is achieved using a jet compressor. In the jet compressor, the exhaust gas is used as the motive stream and the atmospheric air as the propelled stream. When high pressure motive stream from the engine exhaust is expanded in the nozzle, a low pressure is created at the nozzle exit. Due to this low pressure, atmospheric air is sucked into the expansion chamber of the compressor, where it is mixed and pressurized with the motive stream. The pressure of the mixed stream is further increased in the diverging section of the jet compressor. A percentage volume of the pressurized air mixture is then inducted back into the engine as supercharged air and the balance is let out as exhaust. This process not only saves the mechanical power required for supercharging but also dilutes the constituents of the engine exhaust gas thereby reducing the emission and the noise level generated from the engine exhaust. The geometrical design parameters of the jet compressor were obtained by solving the governing equations using the method of constant rate of momentum change. Using the theoretical design parameters of the jet compressor, a computational fluid dinamics analysis using FLUENT software was made to evaluate the performance of the jet compressor for the application of supercharging an IC engine. This evaluation turned out to be an efficient diagnostic tool for determining performance optimization and design of the jet compressor. A jet compressor was also fabricated for the application of supercharging and its performance was studied.

  16. Noise evaluation of automotive A/C compressor

    Directory of Open Access Journals (Sweden)

    Sameh M. Metwally, Mohamed I. Khalil, Shawki A. Abouel-seoud


    Full Text Available Passenger compartment's interior noise and thermal performance are essential criteria for the driving comfort of vehicles. The air-conditioning system influences both field of comfort. It creates comfortable thermal conditions. On the other hand, the noise radiation of the air-condition system's components can be annoying. The blower, the air distribution ducts and the registers affect air rush noise. In some cases, the refrigerant flow creates hissing noise. Such noise has a great influence on vehicle acoustical comfort and on overall quality perception of a vehicle Therefore, the acoustic performance of air-condition compressors become more important for passenger comfort. At engine idling and at extreme temperatures the air-condition compressor can be audible as the significant sound source. However, the aim of this paper is to quantify air-borne noise characteristics of vehicle air-condition compressor. A simulated experimental model comprises a small wooden box with dimensions of 0.5 x 0.5 x 0.5 m represented the principle of hemi-anechoic room was designed and acoustic characteristics of the sound field inside the box were determined. The air-condition compressor characteristics parameters considered in this paper are fan position and electric motor speed. In addition, a single number of the air column natural frequency is calculated. The results indicate that significant information can be obtained in order to investigate the vehicle air-condition compressor and consequently improve the vehicle interior quietness.

  17. Simulation and Optimization of a Suspension Mechanism of Bus’s Air-conditioning Compressors%大客车空调压缩机悬置机构优化仿真

    Institute of Scientific and Technical Information of China (English)

    陈述; 范让林; 梁策


    改进大客车常用曲轴连杆式空调压缩机悬置机构,基于与汽车动力总成悬置系统的相似性,考虑发动机振动和带传动对压缩机振动影响,建立压缩机总成—发动机集总参数模型。以系统能量解耦率为优化目标,系统固有频率和悬置刚度约束作为约束条件,悬置的三向刚度值为设计变量进行优化设计。基于ADAMS建立压缩机总成—发动机动力学模型,仿真结果表明悬置机构改进后压缩机振动减弱,优化后悬置支反力、压缩机质心纵向位移和绕转动轴角加速度明显下降,证明改进悬置机构和优化方法对压缩机隔振的可行性和有效性。%Crankshaft-link type suspension mechanism is commonly used in air-conditioning compressors of improved buses. In this paper, based on the similarity of the automotive powertrain mounting system, a compressor-assembly and engine-lumped parameter model was built to study the engine and belt vibrations. Taking the system energy decoupling rate as the optimization target, the system natural frequency and suspension stiffness as the constraint condition, and the stiffness values in the three special directions as the design variables, optimal design of the suspension mechanism was done. The compressor-assembly and engine-lumped dynamic model was established by means of ADAMS code. Results of simulation show that the vibration of the compressor suspension mechanism is reduced after the improvement. The suspension reaction forces, longitudinal displacement of the mass centroid axis of the compressor, and the angular acceleration about the vertical axis are effectively decreased. The results have proved the feasibility and effectiveness of the optimized model in compressor’s vibration isolation.

  18. 新型直线往复式空压机的结构及其运动特性分析%Constitution of a kind of linear reciprocating air compressor and its motion characteristics analysis

    Institute of Scientific and Technical Information of China (English)



    为了减少往复式空压机活塞对气缸的侧压力,提出一种新型齿轮约束直线往复活塞式空气压缩机,该机利用一对规格相同、面对面布局并且转向相反的锥齿轮,各自驱动一个连杆,并由这2个连杆共同驱动活塞作纯粹的直线往复运动。与传统的往复活塞式空压机相比,新型空压机可以实现活塞与气缸的无侧压运动配合,而且活塞往复运动派生的往复惯性力、连杆摇摆运动派生的摇摆惯性力矩均可以有效平衡。%A new type of gear-restrained linear reciprocating air compressor is proposed to reduce the sidepressure between the piston and the cylinder, m winch two bevel gears wlm same size are setface to and rotates in opposite direction, as well as respectively drive two connecting rods that jointly drive the piston to make pure linear reciprocation. Compared with the conventional reciprocating air compressor, the new-type compressor can realize movement fit of the piston and the cylinder without side pressure, and the reciprocating inertia force produced from the piston's reciprocating movement and the swing inertia torque produced from the connecting rod's swing movement can be easily eliminated.

  19. 30 CFR 75.344 - Compressors. (United States)


    ... air course or to the surface and equipped with sensors to monitor for heat and for carbon monoxide or smoke. The sensors shall deenergize power to the compressor, activate a visual and audible alarm located... every 31 days, sensors installed to monitor for carbon monoxide shall be calibrated with a...

  20. 中央空调压缩机驱动电机绕组重绕时的维修工艺%The Central Air-conditioning Compressor Actuates Time Electric Motor Winding Reroll Service Craft

    Institute of Scientific and Technical Information of China (English)



    中央空调用压缩机电机,工作条件十分恶劣。在电机大修更换绕组后,由于维修工艺达不到要求,运行时间极短即烧毁,导致维修失败的例子很多。可以说维修工艺水平,是空调压缩机电机更换绕组成功的关键,必须予以极大的注意。%The central air conditioning uses the compressor electrical machinery overhaul replacement winding, because the electrical machinery, the working condition to be very bad. After service craft cannot meet the requirements, the running time is short is the over burning extremely, causes the service defeat's example to be many. May say that the service technological level, is the air-conditioning compressor electrical machinery replacement winding successful key, must in by the enormous attention.

  1. Study of Permanent Magnet Synchronous Motor Used in Compressor for High-Efficient Inverter Air Conditioner%高效变频空调压缩机用永磁同步电机研究

    Institute of Scientific and Technical Information of China (English)

    张少丕; 陈世元; 皮明超


    Critical dimension of permanent magnet synchronous motor used in compressor for the home inverter air conditioner was confirmed by magnetic circuit analysis method, and motor performances were calculated accurately by finite element method. Comparing the difference between theoretical designed value and testing value of motor performances, compared the performance of inverter compressor and the corresponding air conditioner, the actual test showed that this method was accurate and feasible.%拟采用磁路解法确认家用变频空调器的压缩机用调速永磁同步电机的关键尺寸,再利用有限元分析方法精确计算电机的各项性能。对比电动机性能的理论设计值与实际测试值的差异,同时对比了变频压缩机和对应空调器的性能,通过实际测试说明该方法的准确性与可行性。

  2. Compressor station layout considerations

    Energy Technology Data Exchange (ETDEWEB)

    Kurz, Rainer; Ohanian, Sebouh; Lubomirsky, Matt [Solar Turbines Incorporated, San Diego, CA (United States)


    This paper discusses issues that influence the decision on the arrangement of compressors and the type of equipment in gas pipeline compressor stations. Different concepts such as multiple small units versus single large units are considered, both regarding their impact on the individual station and the overall pipeline. The necessity of standby units is discussed. Various concepts for drivers (gas turbine, gas motor and electric motor) and compressors (centrifugal and reciprocating) are analyzed. The importance of considering all possible operating conditions is stressed. With the wide range of possible operating conditions for the pipeline in mind, the discussion is brought into the general context of operational flexibility, availability, reliability, installation issues, remote control, and operability of gas turbine driven centrifugal compressors compared to other solutions such as electric motor driven compressors or gas engine driven reciprocating compressors. The impact of different concepts on emissions and fuel cost is discussed. Among the assumptions in this paper are the performance characteristics of the compressor. This paper outlines how these performance characteristics influence the conclusions. (author)

  3. Analysis of the Shutdown Fault in Ingersoll Rand Screw Air Compressor%英格索兰螺杆空压机停机故障分析

    Institute of Scientific and Technical Information of China (English)



    This paper has analyzed the phenomenon of trouble - free record of downtime emerging in Ingersoll Rand screw compressor and points out diagnosis method and solutions.%针对荚格索兰螺杆压缩机出现的无故障记录停机的现象进行分析,并提出诊断手段及解决措施.

  4. Thermoacoustic compressor; Netsuonkyo asshukuki

    Energy Technology Data Exchange (ETDEWEB)

    Matsubara, Y. [Nihon University, Tokyo (Japan). Atomic Energy Research Institute


    With the advance of practical application research of pulse tube refrigerating machine, the ideal way of the compressor as a pressure oscillation source becomes a problem. Recently, the combination between heat sound compressor and pulse tube refrigerating machine, which rapidly develop, is noticed as a refrigeration system, which completely does not have mechanical moving part. Then, it tried to grope for the new possibility by comparing with the usual method. (NEDO)

  5. Similarity and cascade flow characteristics of a highly loaded helium compressor

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Bin, E-mail: [College of Power & Energy Engineering of Harbin Engineering University, Harbin 150001 (China); Chen, Zhongliang [College of Power & Energy Engineering of Harbin Engineering University, Harbin 150001 (China); Chen, Hang [AVIG Shenyang Engine Design and Research Institute, Shenyang 110015 (China); Zhang, Hai; Zheng, Qun [College of Power & Energy Engineering of Harbin Engineering University, Harbin 150001 (China)


    Highlights: • The deviation of different similarity criteria is analyzed theoretically. • Flow difference between helium and air compressor cascades is analyzed numerically. • The analysis of calculated results validates the theoretical derivation. • Flow characteristics of highly loaded helium compressor blade profile are computed. - Abstract: Helium compressor is a major component of the Power Conversion Unit (PCU) used in a High Temperature Gas Cooled Reactor (HTGR). Because the high cost of closed cycle test and leakage problem of helium gas, air could be used as working fluid instead of helium in compressor performance tests. However, the properties of Helium are largely different from those of air, e.g. the adiabatic exponent of Helium is 1.6, while the adiabatic exponent itself is a criterion of similarity between the two compressors. The characteristics of compressor will be different due to the effect of the adiabatic exponent of working fluid, especially for highly loaded compressor working at higher inlet Mach number. In this paper, a theoretical study on the similarity between air compressor and a highly loaded helium compressor is carried out and the deviation of similarity is analyzed. Numerical simulations are then used to confirm the theoretical analysis. The results indicate that the similarity deviation could not be neglected for highly loaded compressor cascade, which means the experience and experimental results of those conventional air compressor cannot be applied directly to the design of highly loaded helium compressor. The flow characteristics of a highly loaded helium compressor at different Reynolds numbers, attack angles, Mach numbers and cascade geometries are then investigated.

  6. 润滑梯度材料LGM在车用空调压缩机滑履中的应用%Application of lubrication gradient material(LGM)in sliding shoes of automotive air conditioning compressor

    Institute of Scientific and Technical Information of China (English)

    张昕辉; 张弋飞; 刘华; 周继峥


    润滑梯度材料(LGM)应用在乘用车空调压缩机滑履(又称滑靴)上,使滑履平均摩擦因数降低39.5%,平均摩擦功降低51.3%,使用寿命提高1.5~3.4倍.制订了验收标准和技术条件.装备LGM滑履的空调压缩机先后配套于上海大众、通用及上海汽车.投产35个月,累计装车104.4万台,实现了热处理自主创新和产业化.%The lubrication gradient material (LGM) was used for making sliding shoes of automotive air-conditioning compressor. Average friction coefficient of the sliding shoes treated with LGM decreases 39.5% ,the average friction power is 51.3% lower than before,its service life increase 1.5-3.4 times. Original LGM acceptance criteria and technique standard in quality system were formulated. 1. 044 million vehicles were accumulatively assembled with LGM compressor from the year of 2007 ,including the brands of Shanghai Volkswagen, General Motor and SAIC motor. A successful pioneer of industrialization of intellectual property was created in China heat treatment industry.

  7. Seneca Compressed Air Energy Storage (CAES) Project

    Energy Technology Data Exchange (ETDEWEB)



    This document provides specifications for the process air compressor for a compressed air storage project, requests a budgetary quote, and provides supporting information, including compressor data, site specific data, water analysis, and Seneca CAES value drivers.

  8. Cold Climate Heat Pumps Using Tandem Compressors

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Bo [ORNL; Abdelaziz, Omar [ORNL; Rice, C Keith [ORNL; Baxter, Van D [ORNL


    In cold climate zones, e.g. ASHRAE climate regions IV and V, conventional electric air-source heat pumps (ASHP) do not work well, due to high compressor discharge temperatures, large pressure ratios and inadequate heating capacities at low ambient temperatures. Consequently, significant use of auxiliary strip heating is required to meet the building heating load. We introduce innovative ASHP technologies as part of continuing efforts to eliminate auxiliary strip heat use and maximize heating COP with acceptable cost-effectiveness and reliability. These innovative ASHP were developed using tandem compressors, which are capable of augmenting heating capacity at low temperatures and maintain superior part-load operation efficiency at moderate temperatures. Two options of tandem compressors were studied; the first employs two identical, single-speed compressors, and the second employs two identical, vapor-injection compressors. The investigations were based on system modeling and laboratory evaluation. Both designs have successfully met the performance criteria. Laboratory evaluation showed that the tandem, single-speed compressor ASHP system is able to achieve heating COP = 4.2 at 47 F (8.3 C), COP = 2.9 at 17 F (-8.3 C), and 76% rated capacity and COP = 1.9 at -13 F (-25 C). This yields a HSPF = 11.0 (per AHRI 210/240). The tandem, vapor-injection ASHP is able to reach heating COP = 4.4 at 47 F, COP = 3.1 at 17 F, and 88% rated capacity and COP = 2.0 at -13 F. This yields a HSPF = 12.0. The system modeling and further laboratory evaluation are presented in the paper.

  9. Design of the Secondary Heat Exchange Device for Waste Heat Recovery of Air Compressor%空压机余热回收二次换热装置的设计研究

    Institute of Scientific and Technical Information of China (English)

    岳畏畏; 陈雷田; 徐新恒; 赵新红


    随着能源紧张与环境污染等问题的出现,余热回收利用技术变得尤为重要。在余热回收技术领域中,喷油螺杆式空压机余热回收越来越受重视。余热回收装置作为空压机余热回收技术中较为重要的设备,对其进行设计研究很有必要。通过理论计算,集成了对应160 kW喷油螺杆空压机的余热回收二次换热装置,该装置可实现油温自动控制,并有效降低板换结垢的风险,对其进行热回收特性实验研究,结果表明在一次侧进出口水温70℃/50℃、二次侧进出口水温45℃/60℃工况下,热回收能量为99.85 kW,高于空压机额定功率的50%。为空压机余热回收系统设计提供参考依据,对系统施工安装起到了一定的促进作用。%The waste heat recycling technology is particularly important with the emergence of energy tension and environmental pollu-tion. The heat recovery of injection screw air compressor is more and more crucial in the waste heat recovery technology field, so it is neces-sary to research waste heat recovery device. Through the theoretical calculation, integrating the waste heat recovery of secondary heat exchange device on the injection screw air compressor with the corresponding power is 160kw. The device can realize the automatic control of oil tem-perature; meanwhile, it also can effectively reduce the risk of plate in scaling. Results from the experimental research on the heat recovery characteristics show that in the condition of import and export water temperature is 70℃/50℃ of the primary side, or import and export water temperature is 45℃/60℃of the secondary side, the heat recovery power is 99.85kW. It is higher than 50% of the air compressor power rating. This paper provides reference for air compressor heat recovery system design and also plays a certain role in promoting the system installation.

  10. XP CEN/TS 14825 (June 2004). Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling. Testing and rating at part load conditions; XP CEN/TS 14825 Juin 2004 Climatiseurs, groupes refroidisseurs de liquide et pompes a chaleur avec compresseur entraine par moteur electrique pour le chauffage et la refrigeration. Essais et determination des caracteristiques a charge partielle

    Energy Technology Data Exchange (ETDEWEB)



    This technical specification covers the tests of air conditioners, heat pumps and liquid chillers in partial load conditions. It specifies the terms and definitions, the testing methods, the test report and the calculation method when the power reduction is due to the cyclic operation of the apparatus or to a power reduction of the compressor(s). The power reductions linked with the temperatures or with the system are excluded. (J.S.)

  11. Electrochemical Hydrogen Compressor

    Energy Technology Data Exchange (ETDEWEB)

    Lipp, Ludwig [FuelCell Energy, Inc., Torrington, CT (United States)


    Conventional compressors have not been able to meet DOE targets for hydrogen refueling stations. They suffer from high capital cost, poor reliability and pose a risk of fuel contamination from lubricant oils. This project has significantly advanced the development of solid state hydrogen compressor technology for multiple applications. The project has achieved all of its major objectives. It has demonstrated capability of Electrochemical Hydrogen Compression (EHC) technology to potentially meet the DOE targets for small compressors for refueling sites. It has quantified EHC cell performance and durability, including single stage hydrogen compression from near-atmospheric pressure to 12,800 psi and operation of EHC for more than 22,000 hours. Capital cost of EHC was reduced by 60%, enabling a path to meeting the DOE cost targets for hydrogen compression, storage and delivery ($2.00-2.15/gge by 2020).

  12. Hyperbolically Shaped Centrifugal Compressor

    Institute of Scientific and Technical Information of China (English)

    Romuald Puzyrewski; Pawel Flaszy(n)ski


    Starting from the classical centrifugal compressor, cone shaped in meridional cross section, two modifications are considered on the basis of results from 2D and 3D flow models. The first modification is the change of the meridional cross section to hyperbolically shaped channel. The second modification, proposed on the basis of 2D axisymmetric solution, concerns the shape of blading. On the strength of this solution the blades are formed as 3D shaped blades, coinciding with the recent tendency in 3D designs. Two aims were considered for the change of meridional compressor shape. The first was to remove the separation zone which appears as the flow tums from axial to radial direction. The second aim is to uniformize the flow at exit of impeller. These two goals were considered within the frame of 2D axisymmetric model. Replacing the cone shaped compressor by a hyperbolically shaped one, the separation at the corner was removed. The disc and shroud shape of the compressor was chosen in the way which satisfies the condition of most uniform flow at the compressor exit. The uniformity of exit flow from the rotor can be considered as the factor which influences the performance of the diffuser following the rotor. In the 2D model a family of stream surfaces of S1 type is given in order to find S2 surfaces which may be identified with the midblade surfaces of compressor blading. A computation of 3D type has been performed in order to establish the relations between 2D and 3D models in the calculation of flow parameters. In the presented example the 2D model appears as the inverse model which leads to 3D shape of blading whereas the 3D model has been used for the direct solution. In the presented example the confrontation of two models, 2D and 3D, leads to a better understanding of the application of these models to the design procedure.

  13. Finite Element Analysis of the Floating Head Structure in Air Compressor Cooling Devices%空气压缩机用冷却装置浮动头结构有限元分析

    Institute of Scientific and Technical Information of China (English)

    王坤; 陈恩; 郭建; 魏纪君; 崔哲


    Air compressors produce air of high temperature and high pressure while working,so heat of the air should be taken away by cooling devices between stages.The floating head, which bears severe laod, is the key part of the cooling devices. This paper, based on the ANSYS environment,carries out the dynamic analysis of the float head force condition in the highest working pressure.This paper provides a guarantee for the safe and reliable operation of the floating head and sug-gests the solution during the design and manufacture process of the floating head in order to avoid its strength failure.%空气压缩机工作产生高温高压空气,压缩空气的热量由级间冷却装置带走。浮动头是空气压缩机用冷却装置的关键零件,是承受载荷较为严酷的零件。本文借助ANSYS有限元仿真软件,对最高压力状态下浮动头的受力情况进行分析,为浮动头安全可靠地工作提供保证,并为避免浮动头强度失效从制造加工过程提出解决方案。

  14. Development of DC Inverter Scroll Compressor used for Marine Container Refrigeration Unit


    Yokoyama, Tomomi; Kato, Katsumi; Nojima, Nobuhiro; Yoshimura, Keiji; Kitaura, Hiroshi


    In recent years, energy saving of a container ship is becoming one of the most important issues from the point of environmental protection of the global marine transportation business. To solve this problem, we have developed a new gas injection inverter scroll compressor for marine container refrigeration unit. The new compressor is based on a conventional scroll compressor, which has been used in various industrial air conditioners for a long time, with some greatly improved technologies. F...

  15. Compressor reliability survey

    NARCIS (Netherlands)

    Eijk, A.; Lier, L.J. van


    The increasing demand for economic plant operation has led to a critical discussion of the equipment as to selection, design, maintenance and automation. The well-known advantages of the reciprocating compressor such as high efficiency under many different operating conditions, comparatively easy re

  16. Study on an Oscillating Rod Restrained Oil--free Lubrication Reciprocating Piston Air Compressor%摆杆约束往复活塞式无油润滑空气压缩机的研究

    Institute of Scientific and Technical Information of China (English)

    耿葵花; 耿爱农; 李辛沫; 陈君立; 阮勤江


    A new oil--free--reciprocating piston air compressor was proposed. In the new type of compressor, an oscillating rod mechanism was used to ensure the connecting rod and piston working in closely straight reciprocating motion, so that the knocking and side pressure between the cylinder and the piston were decreased significantly. Compared with traditional compressor, the height of the new compressor is reduced by 24% while the noise and friction power are decreased by 7.4% and ldB (A) respectively and the seal ring lifetime is increased by about 10%. A mathematic model was established and the operation characteristics of the oscillating rod were analyzed. The theoretical studies show that the swing amplitude of the piston and seal ring are decreased significantly and the knocking strength and side pressure of cylinder wall are reduced because of the restriction of the oscillating rod, and that the rod's loading condition can be improved by setting the mechanism's quick-return trip correspondence to the compressor's suction stroke.%提出一种新型往复活塞式无油润滑空气压缩机,在传统曲柄连杆机构的基础上增设一个摆杆机构,以此约束连杆和活塞以近乎直线往复的方式进行工作,从而缓解活塞及密封环对气缸的侧压力与敲击强度。与传统机型相比较,新型压缩机摩擦功减小了7.4%,噪声下降约1dB(A),密封环寿命提高约10%,高度降低24%。建立了新型压缩机的数学模型,对其摆杆约束机构的特性进行了分析。研究表明:增设摆杆可以大幅度地减小活塞及密封环相对于气缸的摆动幅度,有利于降低它们对气缸的侧压力和敲击强度;另外,曲柄的运转方向对摆杆机构的运动学特性和动力学特性影响较为明显,将机构的急回行程与压缩机的进气行程呼应设置有利于改善摆杆的受力状况。

  17. Stator Indexing in Multistage Compressors (United States)

    Barankiewicz, Wendy S.


    The relative circumferential location of stator rows (stator indexing) is an aspect of multistage compressor design that has not yet been explored for its potential impact on compressor aerodynamic performance. Although the inlet stages of multistage compressors usually have differing stator blade counts, the aft stages of core compressors can often have stage blocks with equal stator blade counts in successive stages. The potential impact of stator indexing is likely greatest in these stages. To assess the performance impact of stator indexing, researchers at the NASA Lewis Research Center used the 4 ft diameter, four-stage NASA Low Speed Axial Compressor for detailed experiments. This compressor has geometrically identical stages that can circumferentially index stator rows relative to each other in a controlled manner; thus it is an ideal test rig for such investigations.

  18. Cause Analysis and Preventive Measures for Suddenly Opening Blow off Valve of Multi-Shaft Centrifugal Air Compressor%多轴离心式空压机放空阀突然打开的原因分析及防范措施

    Institute of Scientific and Technical Information of China (English)

    邵士铭; 张锡德; 辜兴春


    中国石油天然气股份有限公司塔里木油田石化分公司45万t/a合成氨装置的工艺空气压缩机采用德国AtlasCopco公司的多轴离心式压缩机。简述了该压缩机的工艺流程和控制原理;分析了该压缩机运行时放空阀突然打开并导致二段炉断空气的事故原因;提出了调整操作指标和改进操作方法的防范措施。结果表明,当合成氨装置的负荷由100%减至70%时,严格执行新的操作规定,未发生压缩机放空阀打开的事故。%Multi-shaft centrifugal compressor made by Germany Atlas Copso Company has been used as process air compressor in ammonia synthesis plant with a capacity of 450,000 t/a in Talimu Oil Field Petro-chemical Sub-company, China Petroleum and Natural Gas Stock Company Ltd. , author has briefly described the process flow, and control principle for this compressor; has analyzed the reason of accident that the blow off valve was suddenly opened during running of this compressor and therefore induced to cut off the air flow of the secondary reformer; has presented the preventive measures to adjust operating index and to improve operating method. Result indicates while the load of ammonia synthesis plant is reduced from 100% to 70 % , if the operating stipulation is strictly obeyed, no accident occurs due to opening the blow off vale of this compressor.

  19. Gas Compressor Station Economic Optimization

    Directory of Open Access Journals (Sweden)

    Rainer Kurz


    Full Text Available When considering gas compressor stations for pipeline projects, the economic success of the entire operation depends to a significant extent on the operation of the compressors involved. In this paper, the basic factors contributing to the economics are outlined, with particular emphasis on the interaction between the pipeline and the compressor station. Typical scenarios are described, highlighting the fact that pipeline operation has to take into account variations in load.

  20. Gas Compressor Station Economic Optimization



    When considering gas compressor stations for pipeline projects, the economic success of the entire operation depends to a significant extent on the operation of the compressors involved. In this paper, the basic factors contributing to the economics are outlined, with particular emphasis on the interaction between the pipeline and the compressor station. Typical scenarios are described, highlighting the fact that pipeline operation has to take into account variations in load.

  1. Study on Variable Volume and Gas Injection DC Inverter Air Conditioner Compressor%变频变容喷气增焓空调压缩机的理论与实验研究

    Institute of Scientific and Technical Information of China (English)



    The lower heating capacity in low ambient temperature is the defect of the air-conditioner. Some schemes have been proposed to solve the problem, but they can't improve the quantity of heat more than 50%in low ambient tem-perature and improve efficiency in general temperature at the same time. This paper proposes a vapor-injection varicap compressor, and studies its heating capacity and efficiency properties. The experimental results show that the APF of the air-conditioner increased by 6%when using the vapor-injection varicap compressor, and the quantity of heat increased by 85%, at the same time.%低温制热能力不足问题一直是空调的诟病,研发人员在前期也提出过几种解决温制热量的方案,但都以难满足APF工况下的能效提升和低温-15℃环境温度下高制热量的两个目标。针对这一难题,提出一种集变频技术、变容技术和喷气增焓技术为一体的压缩机设计方案,通过原理分析进行了样机的结构设计,研究其性能及低温能力特性,经验证,搭载空调系统测试时,喷气能力能效提升效果明显,在喷气情况下,搭载系统APF比基准机型提高了约6%,同时,搭载系统的低温-15℃的制热能力相对基准机提升了约85%,效果显著。

  2. Application of "front-loose back compact" slotted fin in air compressor interstage cooler%“前疏后密”开缝翅片在空压机级间冷却器上的应用

    Institute of Scientific and Technical Information of China (English)

    杨挺; 冯苗根


    通过对“前疏后密”开缝翅片和平面翅片的传热、阻力特性的试验结果分析,并结合实际工程的计算分析比较,揭示了开缝翅片的优越性,提出采用“前疏后密“开缝翅片取代平面翅片作为空压机级间冷却器的换热元件,是提高冷却器的换热效率,使产品更新换代的主要发展方向。%The analysis of test results of heat transmission and resistance characteristics of the "front-loose back compact" slotted fin and the plane fin, as well as the calculation analysis in combination with actual project show the advantages of the slotted fin and it is pointed that substitution of the "front-loose back compact " slotted fin for the plane fin as the heat exchanging element of air compressor interstage cooler is the main development trend to improve heat exchange efficiency of cooler and upgrade products

  3. 永磁无刷直流电动机在微型空压机中的应用%Application of Permanent Magnet Brushless DC Motor in Miniature Air Compressor

    Institute of Scientific and Technical Information of China (English)

    凌永骧; 张华宗; 余仁田


    Compared with the traditional DC motor and induction motor,permanent magnet brushless DC(BLDC) motor has more superior performance,widely used in many fields,and has a tendency to gradually replace other motors.In this paper,the development and application of permanent magnet brushless DC motor in the miniature air compressor are analyzed.%永磁无刷直流电动机(简称BLDC)与传统的直流电机及感应电动机相比,永磁无刷直流电动机具有更多优越的性能,在许多领域得到了广泛应用,有逐步取代其它电动机的趋势.本文对永磁无刷直流电动机在微型空压机中的应用和发展情况进行分析.

  4. 100 m3/min往复式空压机长周期安全稳定运行研究%Study on Long, Safe and Stable Operation of 100 m3/min Reciprocating Air Compressor

    Institute of Scientific and Technical Information of China (English)



    介绍了安徽晋煤中能化工股份有限公司100 m3/min往复式空压机的工况,针对影响机组长周期稳定、安全运行的问题,采取了优化设备结构和工艺结构的措施,优化结果表明:年创造经济效益16.28万元,实现了节能降耗的目的。%This paper introduces the working conditions of 100 m3/min reciprocating air compressor of Anhui Jinmei Zhongneng Chemical Co. , Ltd. To solve the problem affecting long, safe and stable operation of the unit, the author optimizes the structures of the equipment and the process. The opti-mization results show that it has gained 162 800 RMB yuan/a economic benefit and achieved its energy-saving and consumption-reducing purpose.

  5. A study on the oil flow characteristics in the inverter rotary compressor (United States)

    Kim, H. J.; Kim, Y. J.


    In order to secure the reliability of the oil in the inverter rotary compressor used in the system multi-air conditioners in heating and cooling modes, it is necessary to study the oil flow characteristics which affect to the compressor efficiency. In this study, sight glasses were installed at the compressor and accumulator for oil flow measurements, and various experiments were performed to measure the amount of discharged oil for different refrigerant pipe lengths. On the basis of the experimental measurements, we compared the OCR (Oil Circulation Rate) results of the system multi-air conditioner for various operating conditions. The results are graphically depicted.

  6. Cooling system at the compressors air inlet of the gas turbines from the Tula`s combined cycle central; Sistema de enfriamiento en la succion del compresor de las turbinas de gas de la central de ciclo combinado de Tula

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez F, Oscar [Comision Federal de Electricidad, Tula (Mexico); Romero Paredes, Hernando; Vargas, Martin; Gomez, Jose Francisco [Universidad Autonoma Metropolitana-Iztapalapa, Mexico, D. F. (Mexico)


    It has been formerly evaluated that it is possible to enhance notably the electric power generation in gas turbine power plants by cooling the air at the compressor inlet. It has been pointed out that provided a source of waste heat is available it can be very attractive the use of absorption refrigeration systems. In this paper the technical and the economical benefits of bringing the air inlet temperature down 8 Celsius degrees of the four gas turbines of the Combined Cycle Central of Tula, in the State of Hidalgo (combined cycle central-Tula) are evaluated. The results show that it is possible to achieve an efficiency enhancement of at least 1%, and that in very warm days up to 48 additional Megawatts can be generated, or about 10% of the installed capacity. The final economic result is very encouraging and an annual economical benefit in the order of 50 million pesos can be obtained and the refrigeration units can be amortized in approximately one year. [Espanol] Se ha evaluado anteriormente que es posible mejorar notablemente la capacidad de generacion electrica en plantas que utilizan turbinas de gas, mediante el enfriamiento del aire de succion del compresor. Se ha senalado que en la medida en que se encuentre disponible una fuente termica de desecho puede ser muy atractivo el uso de sistemas de refrigeracion por absorcion. En el presente trabajo se evaluan los beneficios tecnicos y economicos que puede tener el llevar el aire de succion hasta una temperatura de 8 grados Celsius, de las cuatro unidades de gas de la Central de Ciclo Combinado de Tula, Hidalgo (CCC-Tula). Los resultados muestran que es posible alcanzar un aumento en la eficiencia de al menos 1% y que se pueden generar, en dias muy calurosos, hasta 48 MW extras, equivalente al 10% de la capacidad instalada. El resultado economico final es muy alentador y puede llegar a tenerse un beneficio economico del orden de los 50 millones de pesos anuales y las unidades de refrigeracion podran pagarse en

  7. Hermetic compressor and block expansion valve in refrigeration performance (United States)

    Santoso, Budi; Susilo, Didik Djoko; Tjahjana, D. D. D. P.


    Vehicle cabin in tropical countries requires the cooling during the day for comfort of passengers. Air conditioning machine is commonly driven by an internal combustion engine having a great power, which the conventional compressor is connected to crank shaft. The stage of research done is driving the hermetic compressor with an electric motor, and using block expansion valve. The HFC-134a was used as refrigerant working. The primary parameters observed during the experiment are pressure, temperature, and power consumption for different cooling capacities. The results show that the highest coefficient of performance (COP) and the electric power of system are 6.3 and 638 Watt, respectively.

  8. Compressor performance aerodynamics for the user

    CERN Document Server

    Gresh, Theodore


    Compressor Performance is a reference book and CD-ROM for compressor design engineers and compressor maintenance engineers, as well as engineering students. The book covers the full spectrum of information needed for an individual to select, operate, test and maintain axial or centrifugal compressors. It includes basic aerodynamic theory to provide the user with the ""how's"" and ""why's"" of compressor design. Maintenance engineers will especially appreciate the troubleshooting guidelines offered. Includes many example problems and reference data such as gas propert

  9. Dual capacity reciprocating compressor (United States)

    Wolfe, Robert W.


    A multi-cylinder compressor 10 particularly useful in connection with northern climate heat pumps and in which different capacities are available in accordance with reversing motor 16 rotation is provided with an eccentric cam 38 on a crank pin 34 under a fraction of the connecting rods, and arranged for rotation upon the crank pin between opposite positions apart so that with cam rotation on the crank pin such that the crank throw is at its normal maximum value all pistons pump at full capacity, and with rotation of the crank shaft in the opposite direction the cam moves to a circumferential position on the crank pin such that the overall crank throw is zero. Pistons 24 whose connecting rods 30 ride on a crank pin 36 without a cam pump their normal rate with either crank rotational direction. Thus a small clearance volume is provided for any piston that moves when in either capacity mode of operation.

  10. Electrochemical Hydrogen Compressor

    Energy Technology Data Exchange (ETDEWEB)

    David P. Bloomfield; Brian S. MacKenzie


    The Electrochemical Hydrogen Compressor EHC was evaluated against DOE applications for compressing hydrogen at automobile filling stations, in future hydrogen pipelines and as a commercial replacement for conventional diaphragm hydrogen compressors. It was also evaluated as a modular replacement for the compressors used in petrochemical refineries. If the EHC can be made inexpensive, reliable and long lived then it can satisfy all these applications save pipelines where the requirements for platinum catalyst exceeds the annual world production. The research performed did not completely investigate Molybdenum as a hydrogen anode or cathode, it did show that photoetched 316 stainless steel is inadequate for an EHC. It also showed that: molybdenum bipolar plates, photochemical etching processes, and Gortex Teflon seals are too costly for a commercial EHC. The use of carbon paper in combination with a perforated thin metal electrode demonstrated adequate anode support strength, but is suspect in promoting galvanic corrosion. The nature of the corrosion mechanisms are not well understood, but locally high potentials within the unit cell package are probably involved. The program produced a design with an extraordinary high cell pitch, and a very low part count. This is one of the promising aspects of the redesigned EHC. The development and successful demonstration of the hydraulic cathode is also important. The problem of corrosion resistant metal bipolar plates is vital to the development of an inexpensive, commercial PEM fuel cell. Our research suggests that there is more to the corrosion process in fuel cells and electrochemical compressors than simple, steady state, galvanic stability. It is an important area for scientific investigation. The experiments and analysis conducted lead to several recommended future research directions. First, we need a better understanding of the corrosion mechanisms involved. The diagnosis of experimental cells with titration to

  11. 基于Mathcad和Monte-Carlo法的空压机能效测量不确定度分析%Uncertainty Analysis of Air Compressor Energy Efifciency Measurement Based on Mathcad and Monte-Carlo Method

    Institute of Scientific and Technical Information of China (English)

    张杰梁; 黄洪; 姜苏娜; 杭晨哲; 余时帆


    In order to analyze the uncertainty of air compressor energy efifciency measurement, in view of the complicated mathematical model and the dififculty in using the linear model, the uncertainty evaluation method based on Mathcad and Monte Carlo (Monte-Carlo) method is proposed. Through the Monte-Carlo simulation histogram distribution type selection is proved to be correct, the relative expanded uncertainty of measurement results are obtained. Finally, comparison has been made between the Monte-Carlo method and GUM method. The results shows that the relative expanded uncertainty of two methods are close and meet the requirement.%文中为分析容积式空气压缩机能效测量不确定度,针对其数学模型复杂、难以用线性模型近似等问题,提出了基于Mathcad和蒙特卡洛(Monte-Carlo)法不确定度评定方法,并通过Monte-Carlo模拟直方图验证分布类型选择的正确性,进而得出测量结果的相对扩展不确定度。最后,通过GUM法对所评定的不确定度进行比较与分析。分析结果表明,两种不确定度评定结果相近,相对扩展不确定度满足空气压缩机能效级差的“1/3”要求。

  12. Optimization of the working process of the axial compressor according to the criterion of efficiency (United States)

    Baturin, O. V.; Popov, G. M.; Goryachkin, E. S.; Novikova, Yu D.


    The paper shows search results of the optimal shape of low pressure compressor blades of the industrial gas turbine plant using methods of computational fluid dynamics and multicriteria methods of mathematical optimization. The essence of the methods is that an increase in compressor efficiency should be achieved by increasing the degree of compression up to 2%, and reducing the air flow to 8% relative to basic engine parameters. However, the compressor design elements should be retained as maximally unchanged as possible. During the work, the calculation model of the workflow in the test compressor has been developed and verified in the NUMECA software package, the automated algorithm of the blades shape change has been also developed using a small number of variables, while maintaining its stress-strain state. It allows reducing the number of changeable variables more than twofold. As the result of this study, the option of compressor performance was found, which can increase its efficiency by 1.3% (abs.).

  13. Study on ILC bunch compressor

    Institute of Scientific and Technical Information of China (English)


    In this paper, we have found a new set of parameters for the short two-stage ILC bunch compres-sors. The RF sections are both in the accelerating phase rather than the decelerating phase to improve the accelerating efficiency. We have also studied the CSR related issues. The results show that the microbunch instability exists extensively in the second bunch compressor, but the emittance dilution is small due to the relatively long bunch.

  14. Study on Water Lubricated Seal for Single Screw Air Compressor%单螺杆空压机水润滑密封研究

    Institute of Scientific and Technical Information of China (English)



    Water-lubricated compressed bring about in the design and manufacture,be persecuted by many questions of seal form,seal structure,seal means,prevent corrosion and seal leak,between air compressed cavity and beating.This paper will set forth the research process and the results of solving many different matters.%在水润滑单螺杆空压机的设计制造工作中,曾面临空气压缩腔与轴承之间从密封型式、密封结构、密封方法、预防腐蚀和对密封泄漏物的处理等一系列问题的困扰.阐述了解决这诸多问题的研究过程及所获成果.

  15. Centrifugal compressor design choices for chillers

    Energy Technology Data Exchange (ETDEWEB)

    Brasz, J.J. [United Technologies Carrier, New York, NY (United States)


    The use of centrifugal compressors in the air conditioning and refrigeration industry is currently limited to large water cooled chillers varying in size from about 0.5 to 6 MW cooling capacity. These systems are primarily used for comfort or process cooling applications. All systems try to chill relatively large amounts of indoor or process water by a few degrees Celsius in a refrigerant evaporator. The heat removed from the chilled water is released together with the heat of compression in a refrigerant condenser to cooling tower water, from where it is discharged to the atmosphere. Different centrifugal compressor design concepts are used by the various chiller manufacturers: single-stage versus multi-stage, vaneless versus vaned diffuser, hermetic versus open-drive motors, shrouded versus open impellers, fixed versus variable diffuser geometry, low- versus high-pressure refrigerant. This variability seems strange for a mature industry like the air conditioning and refrigeration industry. This paper will show that the reason for this variability is the product compromise between the various conflicting system requirements with respect to size, cost, efficiency and refrigerant choice. The different system applications of the chillers (e.g. comfort cooling in a equatorial region versus process cooling in a moderate climate zone) play another major role in selecting an optimal centrifugal compression concept. Some general recommendations will be given for applications where a clear choice can be made. (Author)

  16. 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


    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.

  17. Compressor bleed cooling fluid feed system (United States)

    Donahoo, Eric E; Ross, Christopher W


    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.

  18. 影响甲醇新鲜气压缩机长周期运行的原因分析及对策%Analysis of the Influencing Reason for the Long-time Operating of Methanol Fresh Air Compressor and Countermeasures

    Institute of Scientific and Technical Information of China (English)

    王哲; 王军; 曹云飞; 韩军; 张涛


    通过对新鲜气压缩机运行初期故障原因分析,提出了降低事故频率,延长运行周期的处理措施,从而保证了压缩机长周期良好运行,并取得了一定的经济效益.%Based on analyzing the fault reason at the early operating period of fresh air compresor,the treatment measures of lowering fault frequency and prolonging operation cycle are pointed out. So it ensures a good longtime operating of compressor and makes a certain economic benefits.

  19. Empirical Design Considerations for Industrial Centrifugal Compressors

    Directory of Open Access Journals (Sweden)

    Cheng Xu


    Full Text Available Computational Fluid Dynamics (CFD has been extensively used in centrifugal compressor design. CFD provides further optimisation opportunities for the compressor design rather than designing the centrifugal compressor. The experience-based design process still plays an important role for new compressor developments. The wide variety of design subjects represents a very complex design world for centrifugal compressor designers. Therefore, some basic information for centrifugal design is still very important. The impeller is the key part of the centrifugal stage. Designing a highly efficiency impeller with a wide operation range can ensure overall stage design success. This paper provides some empirical information for designing industrial centrifugal compressors with a focus on the impeller. A ported shroud compressor basic design guideline is also discussed for improving the compressor range.

  20. Integral Compressor/Generator/Fan Unitary Structure


    Dreiman, Nelik


    INTEGRAL COMPRESSOR / GENERATOR / FAN UNITARY STRUCTURE.*) Dr. Nelik Dreiman Consultant, P.O.Box 144, Tipton, MI E-mail: An extremely compact, therefore space saving single compressor/generator/cooling fan structure of short axial length and light weight has been developed to provide generation of electrical power with simultaneous operation of the compressor when power is unavailable or function as a regular AC compressor powered by a power line. The generators and ai...

  1. Design, Test, and Evaluation of a Transonic Axial Compressor Rotor with Splitter Blades (United States)


    Postgraduate School NPSMF NPS Military Fan NTG No Tip Gap PS Pressure Side SB Splitter Blade SS Suction Side SolidWorks A solid modeling...lubrication oil to the TASR and drive turbine bearings via an air driven oil mist system. A pre-test checklist is provided in McNab [8] Appendix C...modern high- performance compressor rotors. 79 LIST OF REFERENCES [1] A. J. Wennerstrom, Design of Highly Loaded Axial-Flow Fans and Compressors, White

  2. Compressor Part II: Volute Flow Predictions

    Directory of Open Access Journals (Sweden)

    Yu-Tai Lee


    Full Text Available A numerical method that solves the Reynolds-averaged Navier-Stokes equations is used to study an inefficient component of a shipboard air-conditioning HCFC-124 compressor system. This high-loss component of the centrifugal compressor was identified as the volute through a series of measurements given in Part I of the paper. The predictions were made using three grid topologies. The first grid closes the connection between the cutwater and the discharge diffuser. The other two grids connect the cutwater area with the discharge diffuser. Experiments were performed to simulate both the cutwater conditions used in the predictions. Surface pressures along the outer wall and near the inlet of the volute were surveyed for comparisons with the predictions. Good agreements between the predicted results and the measurements validate the calculations. Total pressure distributions and flow stream traces from the prediction results support the loss distribution through the volute. A modified volute configuration is examined numerically for further loss comparison.

  3. Structure Analysis of a Turbocharger Compressor Wheel Using FEA

    Directory of Open Access Journals (Sweden)

    Shaik Mohammad Rafi


    Full Text Available When people talk about race cars or high-performance sports cars, the topic of turbochargers usually comes up. Turbochargers also appear on large diesel engines. A turbo can significantly boost an engine's horsepower without significantly increasing its weight, which is the huge benefit that makes turbos so popular. Turbochargers are a type of forced induction system. They compress the air flowing into the engine. The advantage of compressing the air is that it lets the engine squeeze more air into a cylinder, and more air means that more fuel can be added. Therefore, you get more power from each explosion in each cylinder. Here in this project we are designing the compressor wheel by using Pro-E and doing analysis by using FEA package. The main aim of the project is to increase the performance of the compressor wheel for this we are changing the material and also we are changing the existing design. By comparing the results we will get the best model from this data we suggests the design modifications to the company to improve the performance of the compressor wheel.

  4. 40 CFR 63.1012 - Compressor standards. (United States)


    ... measured during each compliance test. (g) Reciprocating compressor exemption. Any existing reciprocating... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Compressor standards. 63.1012 Section... Emission Standards for Equipment Leaks-Control Level 1 § 63.1012 Compressor standards. (a)...

  5. Compressor instability with integral methods

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Y.K. Eddie [Nanyang Technological Univ., Singapore (Singapore). School of Mechanical and Aerospace Engineering; Liu, Ningyu [Singapore National Univ. (Singapore). Dept. of Mechanical Engineering


    ''Compressor Instability with Integral Methods'' is a book, to bring together the quick integral approaches and advances in the field for the prediction of stall and surge problem in compressor. This book is useful for people involved in the flow analysis, design and testing of rotating machinery. For students, it can be used as a specialized topic of senior undergraduate or graduate study. The book can also be served as a self-study material to those who keen to acquire this knowledge. In brief, this book focuses on the numerical/computational analysis for the effect of distorted inlet flow propagation on the rotating stall and surge in axial compressors. It gains insight into the basic phenomena controlling these flow instabilities, and reveals the influence of inlet parameters on rotating stall and surge. The book starts from the confirmation and application of Kim et al's integral method and then follows by a development to this method through the proposing and applying a critical distortion line. This line is applied successfully on the stall prediction of in-flight compressor due to flaming of refueling leakage near inlet, a typical real and interesting example of compressor stall and surge operation. Further, after a parametric study on the integral method and the distorted flow field of compressor using Taguchi method, a novel integral method is formulated using more appropriate and practical airfoil characteristics, with a less assumptions needed for derivation. Finally, as an extended work, the famous Greitzer's instability flow model, the well-known B-parameter model applied for analyzing the stall and surge characteristics, is studied parametrically using Taguchi method. (orig.)

  6. Analysis of thrust augmentation of turbojet engines by water injection at compressor inlet including charts for calculating compression processes with water injection (United States)

    Wilcox, E Clinton; Trout, Arthur M


    A psychrometric chart having total pressure (sum of partial pressures of air and water vapor) as a variable, a Mollier diagram for air saturated with water vapor, and charts showing the thermodynamic properties of various air-water vapor and exhaust gas-water vapor mixtures are presented as aids in calculating the thrust augmentation of a turbojet engine resulting from the injection of water at the compressor inlet. Curves are presented that show the theoretical performance of the augmentation method for various amounts of water injected and the effects of varying flight Mach number, altitude, ambient-air temperature, ambient relative humidity, compressor pressure ratio, and inlet-diffuser efficiency. Numerical examples, illustrating the use of the psychrometric chart and the Mollier diagram in calculating both compressor-inlet and compressor-outlet conditions when water is injected at the compressor inlet, are presented.

  7. Meridional Considerations of the Centrifugal Compressor Development

    Directory of Open Access Journals (Sweden)

    C. Xu


    Full Text Available Centrifugal compressor developments are interested in using optimization procedures that enable compressor high efficiency and wide operating ranges. Recently, high pressure ratio and efficiency of the centrifugal compressors require impeller design to pay attention to both the blade angle distribution and the meridional profile. The geometry of the blades and the meridional profile are very important contributions of compressor performance and structure reliability. This paper presents some recent studies of meridional impacts of the compressor. Studies indicated that the meridional profiles of the impeller impact the overall compressor efficiency and pressure ratio at the same rotational speed. Proper meridional profiles can improve the compressor efficiency and increase the overall pressure ratio at the same blade back curvature.

  8. Fluid dynamics [and gas compressors

    Energy Technology Data Exchange (ETDEWEB)

    Kurz, Rainer [Solar Turbines Inc. (United States)


    The author examines the use of computational fluid dynamics in the development of gas compressors. The background to CFD is explained including modelling the geometry and the effects of turbulence. A typical design process is briefly explained and its limitations discussed. (UK)

  9. Axial-Centrifugal Compressor Program (United States)


    vanes was obtained from other engine programs. Actuation rings for the IGV and Stage 1 were manufactured irom box sec- tion extruded 6061 -T6... aluminium , while the Stage 2 actuation ring was machined from 321 stainless steel plate stock. Compressor Assembly The Stage 2 vane tips were ground to length

  10. Pulse compressor with aberration correction

    Energy Technology Data Exchange (ETDEWEB)

    Mankos, Marian [Electron Optica, Inc., Palo Alto, CA (United States)


    In this SBIR project, Electron Optica, Inc. (EOI) is developing an electron mirror-based pulse compressor attachment to new and retrofitted dynamic transmission electron microscopes (DTEMs) and ultrafast electron diffraction (UED) cameras for improving the temporal resolution of these instruments from the characteristic range of a few picoseconds to a few nanoseconds and beyond, into the sub-100 femtosecond range. The improvement will enable electron microscopes and diffraction cameras to better resolve the dynamics of reactions in the areas of solid state physics, chemistry, and biology. EOI’s pulse compressor technology utilizes the combination of electron mirror optics and a magnetic beam separator to compress the electron pulse. The design exploits the symmetry inherent in reversing the electron trajectory in the mirror in order to compress the temporally broadened beam. This system also simultaneously corrects the chromatic and spherical aberration of the objective lens for improved spatial resolution. This correction will be found valuable as the source size is reduced with laser-triggered point source emitters. With such emitters, it might be possible to significantly reduce the illuminated area and carry out ultrafast diffraction experiments from small regions of the sample, e.g. from individual grains or nanoparticles. During phase I, EOI drafted a set of candidate pulse compressor architectures and evaluated the trade-offs between temporal resolution and electron bunch size to achieve the optimum design for two particular applications with market potential: increasing the temporal and spatial resolution of UEDs, and increasing the temporal and spatial resolution of DTEMs. Specialized software packages that have been developed by MEBS, Ltd. were used to calculate the electron optical properties of the key pulse compressor components: namely, the magnetic prism, the electron mirror, and the electron lenses. In the final step, these results were folded

  11. 往复压缩机气流脉动和机械振动的工程控制%Engineering Control for Air Flow Pulsation and Mechanical Vibration in Reciprocating Compressors

    Institute of Scientific and Technical Information of China (English)



    This paper has mainly specified the reasons of causing reciprocating compressors pipeline vibration, the interactional factors and the methods of design, calculation and control in engineering.%叙述了往复压缩机管道振动引起的原因和相互影响的因素,以及工程上设计计算和控制的方法.

  12. Technical aspects of a large size industrial process turbo compressor revamp (United States)

    Świder, Piotr; Kozanecki, Zbigniew, Jr.; Graczykowski, Marek; Kryłłowicz, Władysław


    This paper describes several modernization aspects of the process 8 MW air compressor and its driver. The main aim of the revamp was to increase internal efficiencies of both the compressor and turbine and increase the load of the compressor without additional power consumption. The original pressure ratio was preserved. To meet these requirements a redesign of the flow path of both machineswas necessary.Moreover, the turbineworking conditions were changed from extraction-condensing to condensing. In terms of compressor, impeller blade redesign, adaptation of diffusers and Abradable seals were a part of the scope. The revamp was completed in April 2014 with all the requirements met. This paper covers the general outline and a comparison of the original and modernized machine operating parameters, design and technical assumptions and also describes some problematic issues which occurred during the realization of the project.

  13. Approach to novel design of CO2 based centrifugal compressor

    Directory of Open Access Journals (Sweden)

    Kura Tomasz


    Full Text Available Even though turbomachinery design issues have been investigated almost since the beginning of engineering, its optimization process is still important. With the development of refrigeration devices and ORC based distributed generation facilities, a need for efficient and low-energy compressors and turbines became even more demanding. Such machines working with typical fluid, like air, are well described, but there is a room regarding the fluids like CO2, vapour of organic fluids, etc. The main objective of present studies is to propose a numerical model of the centrifugal compressor, with CO2 as the working fluid. Such unit may be a part of refrigeration cycle. Commonly, the scroll or piston compressors are used in such cases, however some discussed disadvantages show that the novel designs should be looked for. Properly designed centrifugal compressors can have higher efficiency than the presently used. Three dimensional analyses of proposed geometries were conducted – using a model including heat, mass and momentum conservation laws as well as ideal gas law. Verification of the proposed mesh and results was performed in the basis of values obtained using theoretical and empirical equations. With about 700 000 control volumes in the validated model, error of the results was no higher than 5%, with only about 1% in regards to the thermal parameters. Two design proposals were analysed, with performance maps as the main comparison factor. Apart from performance characteristics, the pressure and velocity fields were presented, showing the process of flow structure optimization. The main goal was to reduce negative effects of pressure and velocity gradients on the performance. Proposed precursory design might be a good starting point for further development of compressors. The results of numerical analysis were promising and shows the possibility of proposed design usage in practical applications, however to obtain deep understanding of the

  14. Chapter 22: Compressed Air Evaluation Protocol

    Energy Technology Data Exchange (ETDEWEB)

    Benton, N.


    Compressed-air systems are used widely throughout industry for many operations, including pneumatic tools, packaging and automation equipment, conveyors, and other industrial process operations. Compressed-air systems are defined as a group of subsystems composed of air compressors, air treatment equipment, controls, piping, pneumatic tools, pneumatically powered machinery, and process applications using compressed air. A compressed-air system has three primary functional subsystems: supply, distribution, and demand. Air compressors are the primary energy consumers in a compressed-air system and are the primary focus of this protocol. The two compressed-air energy efficiency measures specifically addressed in this protocol are: high-efficiency/variable speed drive (VSD) compressor replacing modulating compressor; compressed-air leak survey and repairs. This protocol provides direction on how to reliably verify savings from these two measures using a consistent approach for each.

  15. Avoiding compressor surge during emergency shutdown hybridturbine systems

    Energy Technology Data Exchange (ETDEWEB)

    Pezzini, Paolo [University of Genova, Italy; Tucker, David [U.S. DOE; Traverso, Alberto [University of Genova, Italy


    A new emergency shutdown procedure for a direct-fired fuel cell turbine hybrid power system was evaluated using a hardware-based simulation of an integrated gasifier/fuel cell/turbine hybrid cycle (IGFC), implemented through the Hybrid Performance (Hyper) project at the National Energy Technology Laboratory, U.S. Department of Energy (NETL). The Hyper facility is designed to explore dynamic operation of hybrid systems and quantitatively characterize such transient behavior. It is possible to model, test, and evaluate the effects of different parameters on the design and operation of a gasifier/fuel cell/gas turbine hybrid system and provide a means of quantifying risk mitigation strategies. An open-loop system analysis regarding the dynamic effect of bleed air, cold air bypass, and load bank is presented in order to evaluate the combination of these three main actuators during emergency shutdown. In the previous Hybrid control system architecture, catastrophic compressor failures were observed when the fuel and load bank were cut off during emergency shutdown strategy. Improvements were achieved using a nonlinear fuel valve ramp down when the load bank was not operating. Experiments in load bank operation show compressor surge and stall after emergency shutdown activation. The difficulties in finding an optimal compressor and cathode mass flow for mitigation of surge and stall using these actuators are illustrated.

  16. Electrical Driven Means for Reciprocating Piston Compressor(Ⅰ)%往复活塞压缩机的电力驱动之一斑

    Institute of Scientific and Technical Information of China (English)



    This paper has specified the issues in electrical driven for air compressors with large and medium power in reciprocating piston compressors.%扼要论及往复活塞压缩机中的大功率者,及中等功率空压机的电力驱动若干问题.

  17. Modelling fluid flow in a reciprocating compressor

    Directory of Open Access Journals (Sweden)

    Tuhovcak Jan


    Full Text Available Efficiency of reciprocating compressor is strongly dependent on the valves characteristics, which affects the flow through the suction and discharge line. Understanding the phenomenon inside the compressor is necessary step in development process. Commercial CFD tools offer wide capabilities to simulate the flow inside the reciprocating compressor, however they are too complicated in terms of computational time and mesh creation. Several parameters describing compressor could be therefore examined without the CFD analysis, such is valve characteristic, flow through the cycle and heat transfer. The aim of this paper is to show a numerical tool for reciprocating compressor based on the energy balance through the cycle, which provides valve characteristics, flow through the cycle and heat losses from the cylinder. Spring-damping-mass model was used for the valve description. Boundary conditions were extracted from the performance test of 4-cylinder semihermetic compressor and numerical tool validation was performed with indicated p-V diagram comparison.

  18. Modelling fluid flow in a reciprocating compressor (United States)

    Tuhovcak, Jan; Hejčík, Jiří; Jícha, Miroslav


    Efficiency of reciprocating compressor is strongly dependent on the valves characteristics, which affects the flow through the suction and discharge line. Understanding the phenomenon inside the compressor is necessary step in development process. Commercial CFD tools offer wide capabilities to simulate the flow inside the reciprocating compressor, however they are too complicated in terms of computational time and mesh creation. Several parameters describing compressor could be therefore examined without the CFD analysis, such is valve characteristic, flow through the cycle and heat transfer. The aim of this paper is to show a numerical tool for reciprocating compressor based on the energy balance through the cycle, which provides valve characteristics, flow through the cycle and heat losses from the cylinder. Spring-damping-mass model was used for the valve description. Boundary conditions were extracted from the performance test of 4-cylinder semihermetic compressor and numerical tool validation was performed with indicated p-V diagram comparison.

  19. Basic Study on Engine with Scroll Compressor and Expander (United States)

    Morishita, Etsuo; Kitora, Yoshihisa; Nishida, Mitsuhiro

    Scroll compressors are becoming popular in air conditioning and refrigeration. This is primarily due to their higher efficiency and low noise/vibration characteristics. The scroll principle can be applied also to the steam expander and the Brayton cycle engine,as shown in the past literature. The Otto cycle spark-ignition engine with a scroll compressor and expander is studied in this report. The principle and basic structure of the scroll engine are explained,and the engine characteristic are calculated based on the idealized cycles and processes. A prototype model has been proposed and constructed. The rotary type engine has always had a problem with sealing. The scroll engine might overcome this shortcoming with its much lower rubbing speed compared to its previous counterparts,and is therefore worth investigating.

  20. Axial Compressor Reversed Flow Performance. (United States)


    change which occurs at the stall limit of the compresor , the time-owaged data indicates that another flow mode change occurs in the neighborhood of the...surging compression system Into a small amplitude oscillation about the nonrecoverable stall point. This forced oscillation can then decay Into a system...were heavily dependent upon the model used for defining compressor post- stall performance, both steady state end transient, especially In the reve a

  1. Experimental and theoretical investigation of timing jitter inside a stretcher-compressor setup. (United States)

    Klingebiel, Sandro; Ahmad, Izhar; Wandt, Christoph; Skrobol, Christoph; Trushin, Sergei A; Major, Zsuzsanna; Krausz, Ferenc; Karsch, Stefan


    In an optically synchronized short-pulse optical-parametric chirped-pulse amplification (OPCPA) system, we observe a few-100 fs-scale timing jitter. With an active timing stabilization system slow fluctuations are removed and the timing jitter can be reduced to 100 fs standard deviation (Std). As the main source for the timing fluctuations we could identify air turbulence in the stretcher-compressor setup inside the chirped pulse amplification (CPA) pump chain. This observation is supported by theoretical investigation of group delay changes for angular deviations occurring between the parallel gratings of a compressor or stretcher, as they can be introduced by air turbulence.

  2. Update on Scroll Compressor Chamber Geometry


    Bell, Ian; Groll, Eckhard; Braun, James; King, Galen


    The geometry of the scroll compressor determines the efficiency of the scroll compressor and controls all elements of its operation. It is therefore critical to be able to accurately model the volumes of the compressor over the course of a revolution. This paper proposes a novel quasi-analytic formulation of the suction, compression and discharge chambers based on a change of variables from involute angle to polar integration angle. This solution has been compared against a reference polyg...

  3. Aspirated Compressors for High Altitude Engines Project (United States)

    National Aeronautics and Space Administration — Aurora Flight Sciences proposes to incorporate aspirated compressor technology into a high altitude, long endurance (HALE) concept engine. Aspiration has been proven...

  4. Research on Metal Hydride Compressor System

    Institute of Scientific and Technical Information of China (English)


    Ti-Zr series Laves phase hydrogen storage alloys with good hydrogen storage properties, such as large hydrogen capacity, rapid hydriding and dehydriding rate, high compression ratio, gentle plateau, small hysteresis, easily being activated and long cyclic stability etc. for metal hydride compressor have been investigated. In addition, a hydride compressor with special characteristics, namely, advanced filling method, good heat transfer effect and reasonable structural design etc. has also been constructed. A hydride compressor cryogenic system has been assembled coupling the compressor with a J-T micro-throttling refrigeration device and its cooling capacity can reach 0.4 W at 25 K.

  5. Discuss of the Fault of Paranormal Dew Point Temperature for NC-1A/B General Air Compressor%NC-1A/B型通用空气压缩机车露点温度超差故障探讨

    Institute of Scientific and Technical Information of China (English)

    王为奎; 李涛


    The NC-1A/B general air compressor is a kind of high-pressure gas equipment and a macro-equipment largely used in army. It ofen comes forth the paranormal dew point tenperature issue. The causes of paranormal dew point tenperature issue are discussed and the concrete improvemnet measures are given in this paper.%NC-1A/B型通用空气压缩机车是部队大量使用的高压气体设备,是一种通用气源设备,在使用中经常出现露点温度超差问题.针对NC-1A/B型通用空气压缩机车露点温度超差问题的原因进行了初步探讨,并给出具体改进措施.

  6. Oil Leakage from the Seal Ring of a Scroll Compressor (United States)

    Kobayashi, Naoki; Fukui, Atsushi; Horiguchi, Hironori; Tsujimoto, Yoshinobu; Toyama, Toshiyuki

    In scroll compressors for air conditioners, there is a compressor with back-pressure chamber spaced by seal ring behind orbiting scroll. High pressure in the backpressure chamber presses the orbiting scroll to fixed scroll. In the case that lubrication oil and refrigerant gas with high pressure and temperature in the backpressure chamber leak to low pressure chamber through the seal ring, the efficiency of compressor decreases and the oil circulation rate can increase. In the present study the leakage characteristics of lubrication oil from the backpressure chamber to the low pressure chamber were investigated. In experiment, it was found that the oil leakage is larger for higher rotational speed of rotating disk, higher viscosity of oil and smaller pressure difference between the backpressure and low-pressure chambers. This could be explained by the calculation in which the seal ring was assumed to have a tilt angle. It was also found in the calculation that oil leakage is larger due to the thicker oil film between the seal ring and the rotating disk in the case of higher rotational speed of the disk, higher viscosity of oil and smaller pressure difference between the backpressure and low-pressure chambers.

  7. Axial flow positive displacement worm compressor (United States)

    Murrow, Kurt David (Inventor); Giffin, Rollin George (Inventor); Fakunle, Oladapo (Inventor)


    An axial flow positive displacement compressor has an inlet axially spaced apart and upstream from an outlet. Inner and outer bodies have offset inner and outer axes extend from the inlet to the outlet through first and second sections of a compressor assembly in serial downstream flow relationship. At least one of the bodies is rotatable about its axis. The inner and outer bodies have intermeshed inner and outer helical blades wound about the inner and outer axes respectively. The inner and outer helical blades extend radially outwardly and inwardly respectively. The helical blades have first and second twist slopes in the first and second sections respectively. The first twist slopes are less than the second twist slopes. An engine including the compressor has in downstream serial flow relationship from the compressor a combustor and a high pressure turbine drivingly connected to the compressor by a high pressure shaft.

  8. Hub and shroud fillets influence on the radial compressor stage efficiency

    Directory of Open Access Journals (Sweden)

    Syka Tomáš


    Full Text Available Article describes numerical simulations of an air flow in the radial compressor stage in the NUMECA CFD software. During the tasks evaluating the stepped and straight impeller seals and hub and shroud fillets influence on working characteristics and flow field was observed. Also the CFD results comparison with results from the empiric design tool and the measurement is described.

  9. 33 CFR 154.826 - Vapor compressors and blowers. (United States)


    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Vapor compressors and blowers....826 Vapor compressors and blowers. (a) Each inlet and outlet to a compressor or blower which handles...) Excessive shaft bearing temperature. (d) If a centrifugal compressor, fan, or lobe blower handles vapor...

  10. Elimination of microorganisms from dental operatory compressed air. (United States)

    De Ciccio, A; Chan, E C


    Compressed air is used to power high-speed handpieces, as well as to dry and clean surfaces in the oral cavity during patient treatment, in all dental operatories. The compressed air used in the dental operatories located in large institutions such as universities or hospitals is generally obtained from a central source, and is produced by continually running compressors. In operatories located in private practice settings, compressed air is obtained from small on-site air compressors, which may be run less frequently. A survey was made of operatories in the Montreal area to determine the microbial load of the compressed air produced by air compressors. An air sampler was used to collect compressed air and impinge it on a rotating agar medium surface. Compared to the air produced from compressors in constant use, the air collected from compressors that ran intermittently had a very high microbial load. The efficacy of an apparatus designed to sterilize the contaminated air produced by small, on-site compressors was tested. Called a Purilair, this device heats every particle of inflowing compressed air to 250 degrees C and then forces it through a fine-pore ceramic filter. In three private practice operatories, an in-line Purilair effectively sterilized the air being delivered by small compressors. The same result was obtained in the laboratory when lyophilized spores and cells of Bacillus stearothermophilus and conidia of Penicillium notatum and Aspergillus niger were sprayed into the intake line of the apparatus.

  11. Experimental investigation of a forced response condition in a multistage compressor (United States)

    Murray, William Louis, III

    The objective of this research is twofold. Firstly, the design, development, and construction of a test facility for a Honeywell APU-style centrifugal compressor was implemented, as well as the design and construction of an inlet flow experiment. Secondly, the aeromechanical response of an embedded stage in the Purdue 3-Stage axial research compressor was analyzed through a suite of different measurement techniques in the fulfillment of the end of the GUIde IV Consortium contract. The purpose of the first phase of Honeywell work was to comprehensively measure the flow field of an APU-style centrifugal compressor inlet through the use of Laser Doppler Velocimetry (LDV). A portion of a Honeywell supplied inlet was modified to provide optical access to the elbow, and a gas ejector system was designed and constructed to provide the same suction to the inlet that it would see during operation with the compressor. A performance and health monitoring electronics system was designed and purchased to support the testing of the Honeywell inlet ejector system and eventually it will be used for testing with a centrifugal compressor. Additionally, a secondary air and oil system has been designed and is currently being constructed in the test cell in preparation for the arrival of the Honeywell compressor this summer. An embedded rotor stage in the Purdue 3-stage compressor, with a Campbell diagram crossing of the 1T vibratory mode was analyzed with a suite of measurement systems. In addition to steady state compressor performance measurements, other types of measurements were used to characterize the aerodynamic forcing function for this forced response condition including: NSMS, high-frequency pressure transducers mounted in the casing and in a downstream stator, and cross-film thermal anemometry. Rotor geometry was measured by Aerodyne using an in-situ laser scanning technique. Vibrometry testing was performed at WPAFB to characterize safe operating speeds for stator

  12. Compressor Part I: Measurement and Design Modeling

    Directory of Open Access Journals (Sweden)

    Thomas W. Bein


    method used to design the 125-ton compressor is first reviewed and some related performance curves are predicted based on a quasi-3D method. In addition to an overall performance measurement, a series of instruments were installed on the compressor to identify where the measured performance differs from the predicted performance. The measurement techniques for providing the diagnostic flow parameters are also described briefly. Part II of this paper provides predictions of flow details in the areas of the compressor where there were differences between the measured and predicted performance.

  13. Design and Prototyping of Micro Centrifugal Compressor for Ultra Micro Gas Turbine

    Institute of Scientific and Technical Information of China (English)

    Shimpei MIZUKI; Toshiyuki HIRANO; Yoshiyuki KOIZUMI; Gaku MINORIKAWA; Hoshio TSUJITA; Mitsuo IWAHARA; Ronglei GU; Yutaka OHTA; Eisuke OUTA


    In order to establish the design methodology of an ultra micro centrifugal compressor, which is the most important component of an ultra micro gas turbine unit, a 10 times size of the final target compressor (impeller outer diameter 40 mm, corrected rotational speed 220,000 r/min) was designed. The problems to be solved for downsizing were examined and a 2-dimensional impeller was chosen as the first model due to its productivity.The conventional 1D prediction method and CFD were used. The prototyped compressor was tested by using cold air at the reduced speed of 110,000 r/min. Following to the 10 times model, a 5 times size of the final target model having fully 3-dimensional shape (impeller outer diameter 20mm, corrected rotational speed 500,000r/min) was designed and tested by using hot gas at the reduced speed of 250,000 r/min.

  14. Enhancement of centrifugal compressor stable operation using an internal recirculation channel

    Directory of Open Access Journals (Sweden)

    Růžička M.


    Full Text Available Centrifugal compressors with a high pressure ratio are widely used in small aircraft turbine engines and turbocharges. At high rotational speeds they have a narrow stable operating region and the commonly used impellers with back swept blades are not able to ensure requested stability. In order to achieve a wider stable operating region, some other anti-surge measures can be used such as an Internal Recirculation Channel (IRC located in the inlet area of the compressor impeller. This paper analyses the influence of various IRC inlet slot geometries on air flow parameters. The flow velocity profiles downstream of the IRC outlet slot are evaluated and the influence of various channel configurations on compressor performance map is shown. Results from experiments as well as CFD simulations enable us to analyse the airflow in IRC and find out its most suitable geometry.

  15. Development of a Hybrid Compressor/Expander Module for Automotive Fuel Cell Applications

    Energy Technology Data Exchange (ETDEWEB)

    McTaggart, Paul


    In this program TIAX LLC conducted the development of an advanced technology compressor/expander for supplying compressed air to Proton Exchange Membrane (PEM) fuel cells in transportation applications. The overall objective of this program was to develop a hybrid compressor/expander module, based on both scroll and high-speed turbomachinery technologies, which will combine the strengths of each technology to create a concept with superior performance at minimal size and cost. The resulting system was expected to have efficiency and pressure delivery capability comparable to that of a scroll-only machine, at significantly reduced system size and weight when compared to scroll-only designs. Based on the results of detailed designs and analyses of the critical system elements, the Hybrid Compressor/Expander Module concept was projected to deliver significant improvements in weight, volume and manufacturing cost relative to previous generation systems.

  16. Energy-optimal speed control of fans and compressor in a refrigeration system

    DEFF Research Database (Denmark)

    Jakobsen, Arne; Rasmussen, Bjarne D.


    Use of variable speed compressors and variable speed fans for both the evaporator and the condenser makes the refrigeration system more flexible, adds to the degree of freedom of the control system and therefore makes it possible to (on-line) optimise the various speeds involved. Say, for example...... choosing the combination of compressor speed, evaporator fan and condenser fan speeds which minimises the total power consumption of the motors involved. A system and integrated control viewpoint is necessary as a “component-oriented” and “single-loop-control” approach will not lead to the discovery...... that the cooling capacity must be increased due to increased cooling load. This can be done by increasing the compressor speed and/or the evaporator fan speed and also to some extent by increasing the condenser fan speed. The general control problem is to obtain the desired temperature of the cooled air, while...

  17. Experimental Investigations of Micro Air Injection to Control Rotating Stall

    Institute of Scientific and Technical Information of China (English)

    Chaoqun Nie; Zhiting Tong; Shaojuan Geng; Junqiang Zhu; Weiguang Huang


    Steady discrete micro air injection at the tip region in front of the first compressor rotor has been proved to be an effective method to delay the inception of rotating stall in a low speed axial compressor. Considering the practical application a new type of micro injector was designed and described in this paper, which was imbedded in the casing and could be moved along the chord. In order to verify its feasibility to other cases, such as high subsonic axial compressor or centrifugal compressor, some other cases have been studied. Experimental results of the same low speed axial compressor showed that the new injector could possess many other advantages besides successfully stabilizing the compressor. Experiments performed on a high subsonic axial compressor confirmed the effectiveness of micro air injection when the relative velocity at the blade tip is high subsonic. Meanwhile in order to explore its feasibility in centrifugal compressor, a similar micro injector was designed and tested on a low speed centrifugal compressor with vaned diffuser. The injected mass flow was a bit larger than that used in axial compressors and the results showed micro injection could also delay the onset of rotating stall in the centrifugal compressor.

  18. Multi-stage axial flow compressors characteristics estimation based on system identification

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Wentong; Liu, Yongwen; Su, Ming [Key Laboratory for Power Machinery and Engineering of Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240 (China); Yu, Nanhua [Guangdong Electric Power Research Institute, 73 Meihua Road, Guangzhou 510600 (China)


    The most troublesome part in the development of a component-based engine models is the compressor module because of the strong dependence of its performance on rotational speed. For this purpose, a performance characteristics estimation method of multi-stage axial flow compressors are proposed in this paper. The newly proposed estimation technique of average infinitesimal stage characteristics satisfies the analogy criterion perfectly due to the use of a new conception of infinitesimal stage and the improved analogy theory. The overall compressor performance characteristics are estimated through a stage by stage calculation based on the improved analogy theory and the average stage characteristics. To minimize the error between the calculated characteristic and the tested characteristic of the compressor at high rotational speeds, the average stages performance characteristics are identified using an optimization method. The technique improves the traditional scaling method by taking into account the effects of air density change and rotational speeds, and it makes use of available data efficiently. In addition, it reflects the own performance characteristics of the original compressor. (author)

  19. Multi-stage axial flow compressors characteristics estimation based on system identification

    Energy Technology Data Exchange (ETDEWEB)

    Ma Wentong [Key Laboratory for Power Machinery and Engineering of Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240 (China)], E-mail:; Liu Yongwen; Su Ming [Key Laboratory for Power Machinery and Engineering of Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240 (China); Yu Nanhua [Guangdong Electric Power Research Institute, 73 Meihua Road, Guangzhou 510600 (China)


    The most troublesome part in the development of a component-based engine models is the compressor module because of the strong dependence of its performance on rotational speed. For this purpose, a performance characteristics estimation method of multi-stage axial flow compressors are proposed in this paper. The newly proposed estimation technique of average infinitesimal stage characteristics satisfies the analogy criterion perfectly due to the use of a new conception of infinitesimal stage and the improved analogy theory. The overall compressor performance characteristics are estimated through a stage by stage calculation based on the improved analogy theory and the average stage characteristics. To minimize the error between the calculated characteristic and the tested characteristic of the compressor at high rotational speeds, the average stages performance characteristics are identified using an optimization method. The technique improves the traditional scaling method by taking into account the effects of air density change and rotational speeds, and it makes use of available data efficiently. In addition, it reflects the own performance characteristics of the original compressor.

  20. Virtual Training of Compressor Control Room Project (United States)

    National Aeronautics and Space Administration — MYMIC will analyze, design, develop and evaluate the Virtual Control Room – Compressor Station (VCoR-CS) training system. VCoR-CS will provide procedural...

  1. High Speed Compressor for Subcooling Propellants Project (United States)

    National Aeronautics and Space Administration — Propellant densification systems for LH2 require compression systems that develop significant head. In the past this has required multiple stages of compressors...

  2. RELAP5-3D Compressor Model

    Energy Technology Data Exchange (ETDEWEB)

    James E. Fisher; Cliff B. Davis; Walter L. Weaver


    A compressor model has been implemented in the RELAP5-3D© code. The model is similar to that of the existing pump model, and performs the same function on a gas as the pump performs on a single-phase or two-phase fluid. The compressor component consists of an inlet junction and a control volume, and optionally, an outlet junction. This feature permits cascading compressor components in series. The equations describing the physics of the compressor are derived from first principles. These equations are used to obtain the head, the torque, and the energy dissipation. Compressor performance is specified using a map, specific to the design of the machine, in terms of the ratio of outlet-to-inlet total (or stagnation) pressure and adiabatic efficiency as functions of rotational velocity and flow rate. The input quantities are specified in terms of dimensionless variables, which are corrected to stagnation density and stagnation sound speed. A small correction was formulated for the input of efficiency to account for the error introduced by assumption of constant density when integrating the momentum equation. Comparison of the results of steady-state operation of the compressor model to those of the MIT design calculation showed excellent agreement for both pressure ratio and power.

  3. Model based design of an intercooled dual stage sliding vane rotary compressor system (United States)

    Cipollone, Roberto; Bianchi, Giuseppe; Di Battista, Davide; Contaldi, Giulio; Murgia, Stefano


    Energy saving is currently one of the most important driving factors for innovation all over the world. With reference to global electricity consumptions, electrical energy for compressed air production accounts for 4-5%. Among the rotary compressor technologies, Sliding Vane Rotary Compressors (SVRC) are characterized by noteworthy specific energy consumptions and demonstrated an unforeseen energy saving potential thanks to some intrinsic features specifically related to this kind of machines. The paper presents a further reduction strategy to lower energy consumptions in compressed air systems using SVRCs that relies on the combination of the recent use of a pressure swirled oil injection technology and a dual stage intercooling. The synergy between technologies already mature approaches to the lowest energy consumption and candidates SVRCs as superior machines in the energy context. The saving potential compared to the technology at the state of the art was evaluated thanks to a comprehensive mathematical modeling of the two compressor sections and the intercooling heat exchanger and fan. Results showed a reduction of the electrical power required to drive the compressor system up to 9.5%. The overall approach represents a model-based design for a new machine which is under development.

  4. Performance evaluation of high speed compressors for high speed multipliers

    Directory of Open Access Journals (Sweden)

    Nirlakalla Ravi


    Full Text Available This paper describes high speed compressors for high speed parallel multipliers like Booth Multiplier, Wallace Tree Multiplier in Digital Signal Processing (DSP. This paper presents 4-3, 5-3, 6-3 and 7-3 compressors for high speed multiplication. These compressors reduce vertical critical path more rapidly than conventional compressors. A 5-3 conventional compressor can take four steps to reduce bits from 5 to 3, but the proposed 5-3 takes only 2 steps. These compressors are simulated with H-Spice at a temperature of 25°C at a supply voltage 2.0V using 90nm MOSIS technology. The Power, Delay, Power Delay Product (PDP and Energy Delay Product (EDP of the compressors are calculated to analyze the total propagation delay and energy consumption. All the compressors are designed with half adder and full Adders only.

  5. Novel Compressor Blade Design Study (United States)

    Srinivas, Abhay

    Jet engine efficiency goals are driving compressors to higher pressure ratios and engines to higher bypass ratios, each one driving to smaller cores. This is leading to larger tip gaps relative to the blade height. These larger relative tip clearances would negate some of the cycle improvements, and ways to mitigate this effect must be found. A novel split tip blade geometry has been created which helps improve the efficiency at large clearances while also improving operating range. Two identical blades are leaned in opposite directions starting at 85% span. They are cut at mid chord and the 2 halves then merged together so a split tip is created. The result is similar to the alula feathers on a soaring bird. The concept is that the split tip will energize the tip flow and increase range. For higher relative tip clearance, this will also improve efficiency. The 6th rotor of a highly loaded 10 stage machine was chosen as the baseline for this study. Three dimensional CFD simulations were performed using CD Adapco's Star-CCM+ at 5 clearances for the baseline and split tip geometry. The choking flow and stall margin of the split tip blade was higher than that of the baseline blade for all tip clearances. The pressure ratio of the novel blade was higher than that of the baseline blade near choke, but closer to stall it decreased. The sensitivity of peak efficiency to clearance was improved. At tight clearances of 0.62% of blade height, the maximum efficiency of the new design was less than the baseline blade, but as the tip clearance was increased above 2.5%, the maximum efficiency increased. Structural analysis was also performed to ascertain the feasibility of the design.

  6. 40 CFR 60.482-3a - Standards: Compressors. (United States)


    ... Administrator. (j) Any existing reciprocating compressor in a process unit which becomes an affected facility... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards: Compressors. 60.482-3a..., Reconstruction, or Modification Commenced After November 7, 2006 § 60.482-3a Standards: Compressors. (a)...

  7. Coupled Thermodynamic Behavior of New Screw Compressors Rotors Profile

    Directory of Open Access Journals (Sweden)

    Arístides Rivera Torres


    Full Text Available The article displays an evaluation of the thermodynamic behavior of screw compressor rotors with new profiles, obtained with the help of the Scorpath 2000 software. This allows predicting precisely the operation of the compressor, as well as its thermodynamic evaluation, under equal conditions, with the work of other compressors fitted with rotor profiles of other kinds.

  8. 49 CFR 178.337-15 - Pumps and compressors. (United States)


    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pumps and compressors. 178.337-15 Section 178.337... PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.337-15 Pumps and compressors. (a) Liquid pumps or gas compressors, if used, must be of suitable design, adequately...

  9. 49 CFR 178.338-17 - Pumps and compressors. (United States)


    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pumps and compressors. 178.338-17 Section 178.338... PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.338-17 Pumps and compressors. (a) Liquid pumps and gas compressors, if used, must be of suitable design, adequately...

  10. Design and Prototyping of Micro Centrifugal Compressor

    Institute of Scientific and Technical Information of China (English)

    Shimpei Mizuki; Gaku Minorikawa; Toshiyuki Hirano; Yuichiro Asaga; Naoki Yamaguchi; Yutaka Ohta; Eisuke Outa


    In order to establish the design methodology of ultra micro centrifugal compressor, which is the most important component of ultra micro gas turbine unit, a 10 times of the final target size model was designed, prototyped and tested. The problems to be solved for downsizing were examined and 2-dimensional impeller was chosen as the first model due to its productivity. The conventional 1D prediction method, CFD and the inverse design were attempted. The prototyped compressor was driven by using a turbocharger and the performance characteristics were measured.

  11. Active magnetic bearings applied to industrial compressors (United States)

    Kirk, R. G.; Hustak, J. F.; Schoeneck, K. A.


    The design and shop test results are given for a high-speed eight-stage centrifugal compressor supported by active magnetic bearings. A brief summary of the basic operation of active magnetic bearings and the required rotor dynamics analysis are presented with specific attention given to design considerations for optimum rotor stability. The concerns for retrofits of magnetic bearings in existing machinery are discussed with supporting analysis of a four-stage centrifugal compressor. The current status of industrial machinery in North America using this new support system is presented and recommendations are given on design and analysis requirements for successful machinery operation of either retrofit or new design turbomachinery.


    Directory of Open Access Journals (Sweden)



    Full Text Available Hermetic reciprocating compressors are most commonly used in the refrigeration industry. The main source of noise in refrigerating and air conditioning machinery is the compressor. Reduction of noise in compressors is a complex criterion as many factors such as Shell Thickness, Shell Material, Suction Port Area and Discharge Port Area etc. contribute its effect on the noise and they also interact in a complex manner. In this work a screening test is carried out to find the relative effect of the parameters and their interaction, which can be used as an initial step for further investigations concentrating on the most influencing parameters and their interactions using Taguchi Technique. Here Shell Thickness (ST, Shell Material (SM, Suction Port Area (SPA and Discharge Port Area (DPA are chosen as input parameters and the noise is the output parameter. L8 orthogonal array is selected, the factors are assigned and experiments are carried out. Column effect method is used to find the most effective parameters for the noise reduction in the compressor.

  13. Roles and expectations of cold compressor for helium refrigerator

    Energy Technology Data Exchange (ETDEWEB)

    Saji, Nobuyoshi; Asakura, Hiroshi; Yoshinaga, Seiichiro; Ishizawa, Takehiko [Ishikawajima-Harima Heavy Industries Co., Ltd., Yokohama, Kanagawa (Japan)


    Since around 1970, cryogenic systems have required the use of cold compressors. The requirement appeared for two reasons. The first was reduce the pressure of liquid helium with the intention of realizing the stable operation of large superconducting magnets with the best superconducting ability by decreasing operating temperature. The other was to improve the reliability of helium refrigerator compressors by introducing a turbo-compressor with oil-free bearings. This paper describes the circumstances and particular development of cold compressors, requirements related to helium refrigeration systems and cold compressors and future prospects. (author)

  14. Evaluation of methods to decrease the discharge temperature of R32 scroll compressor


    Wang, Baolong; Yang, Minghong; Dewitte, Philippe; Zhang, Leping; Shi, Wenxing


    Recently, R32 has been considered as an important alternative in application of small to middle capacity air conditioner by many countries due to its advantages such as low global warming potential (GWP), favorable thermal properties, less refrigerant charge and low cost. However, the much increased discharge temperature of R32 compressor, as compared with the R22, becomes the main barrier affecting the wide and quick alternation. Refrigerant injection has proven to be effective in decreasing...


    Directory of Open Access Journals (Sweden)

    Wojciech GÓRA


    Full Text Available In this paper a control system of air compressors in a university laboratory is presented. The control system, which is built using the Astraada RCC972 and the GE 90-20 drivers, is an extension of the two states’ inputs and outputs of Astraada. To visualize the work stand, the PC computer class and the Proficy Machine Edition (ME View software were applied. Selected results from the tests of the built control system are presented.

  16. Fault detection and diagnosis for refrigerator from compressor sensor

    Energy Technology Data Exchange (ETDEWEB)

    Keres, Stephen L.; Gomes, Alberto Regio; Litch, Andrew D.


    A refrigerator, a sealed refrigerant system, and method are provided where the refrigerator includes at least a refrigerated compartment and a sealed refrigerant system including an evaporator, a compressor, a condenser, a controller, an evaporator fan, and a condenser fan. The method includes monitoring a frequency of the compressor, and identifying a fault condition in the at least one component of the refrigerant sealed system in response to the compressor frequency. The method may further comprise calculating a compressor frequency rate based upon the rate of change of the compressor frequency, wherein a fault in the condenser fan is identified if the compressor frequency rate is positive and exceeds a condenser fan fault threshold rate, and wherein a fault in the evaporator fan is identified if the compressor frequency rate is negative and exceeds an evaporator fan fault threshold rate.

  17. Compressor Foundation Analysis Tool(COFANTO)

    NARCIS (Netherlands)

    Eijk, A.; Lentzen, S.S.K; Zuada Coelho, B.E.; Galanti, F.M.B.


    Reciprocating compressors are generally supported on a heavy concrete foundation. In spite of the large inertia and stiffness of the foundation, problems can occur due to interaction between the mechanical installation and the foundation. Two types of problems may occur. In the first type, the inter

  18. Advanced electric heat pump dual-stroke compressor and system development (United States)

    Veyo, S. E.; Fagan, T. J.


    The development of an advanced electric heat pump is discussed. A two-capacity, residential, advanced electric heat pump utilizing a unique dual-stroke compressor was developed. Two nearly identical preprototype split systems of nominally 3.5 tons maximum cooling capacity were designed, built and laboratory tested. The estimated annual energy efficiency of this advanced system is 20 percent better than a two-speed electric heat pump available at contract inception in 1979. This superior performance is due to the synergism of a high-efficiency, dual-stroke reciprocating compressor, a dual-strength high-efficiency single-speed single-phase hermetic drive motor, a single-width, single-entry high-efficiency indoor blower with backward curved cambered plate blades, a high-efficiency multivane axial flow outdoor fan, high-efficiency two-speed air mover motors and a microprocessor control system. The relative proportions of heat exchangers, air flows and compressor size as well as the ratio between high and low capacity were optimized so as to minimize the annual cost of ownership in a northern climate. Constraints placed upon the optimization and design process to ensure comfort provide heating air with a temperature of at least 90(0)F and provide cooling with a sensible-to-total capacity ratio of not more than 0.7. System performance was measured in the laboratory in accordance with applicable codes and procedures. Performance data plus hardware details are provided.

  19. To observe the clinical effect of Pulmicort Respules atomizing air compressor pump and oxygen drive atomizationtreatment of infant bronchiolitis%普米克令舒空气压缩泵雾化与氧气驱动雾化治疗较小婴儿毛细支气管炎的临床疗效观察

    Institute of Scientific and Technical Information of China (English)

    梁光明; 伍建平


    Objective:To explore the clinical effect of application of Pulmicort Respules:Atomizing air compressor pump and oxygen drive atomization treatment of infant bronchiolitis caused by smaller, more effective method for the treatment of clear .Methods:Bronchi-olitis is small in our hospital as the research objects and were divided into two groups , based on the received the same conventional treat-ment, the control group were treated with Pulmicort Respules air compressor pump atomizing inhalation therapy , the study group were trea-ted with Pulmicort oxygenatomization inhalation therapy .Comparing the clinical efficacy of two groups of children .Results: After treat-ment , the study group with wheezing , coughing , wheezing , wet rales disappearance time were significantly less than the control group , the hospitalization time was significantly less than that in the control group , the differences were statistically significant (P<0.05).The two groups before treatment in children with respiratory rate were higher , after treatment , the study group were decreased , respiratory rate was significantly lower than the control group(P<0.05);the two groups before treatment, the blood oxygen saturation was low, after treat-ment were increased,the study group was significantly higher than the control group (P<0.05).Conclusion: With the application of Pulmicort Respules inhalation therapy compared with air compressor pump , small for bronchiolitis infants , Pulmicortinhalation therapy effect is better, can significantly improve the blood oxygen saturation of children , help childrenrecover as soon as possible , which has great popularization and application value .%目的:探索分析应用普米克令舒空气压缩泵雾化以及氧气驱动雾化治疗较小婴儿毛细支气管炎所产生的临床作用和效果,明确更有效的治疗方法。方法:选择我院收治的毛细支气管炎较小患儿作为研究对象并进行分组治疗,在接受相同常规

  20. Effect of self recirculation casing treatment on the performance of a turbocharger centrifugal compressor (United States)

    Gancedo, Matthieu

    Increase in emission regulations in the transport industry brings the need to have more efficient engines. A path followed by the automobile industry is to downsize the size of the internal combustion engine and increase the air density at the intake to keep the engine power when needed. Typically a centrifugal compressor is used to force the air into the engine, it can be powered from the engine shaft (superchargers) or extracting energy contained into the hot exhaust gases with a turbine (turbochargers). The flow range of the compressor needs to match the one of the engine. However compressors mass flow operating range is limited by choke on the high end and surge on the low end. In order to extend the operation at low mass flow rates, the use of passive devices for turbocharger centrifugal compressors was explored since the late 80's. Hence, casing treatments including flow recirculation from the inducer part of the compressor have been shown to move the surge limit to lower flows. Yet, the working mechanisms are still not well understood and thus, to optimize the design of this by-pass system, it is necessary to determine the nature of the changes induced by the device both on the dynamic stability of the pressure delivery and on the flow at the inlet. The compressor studied here features a self-recirculating casing treatment at the inlet. The recirculation passage could be blocked to carry a direct comparison between the cases with and without the flow feature. To grasp the effect on compressor stability, pressure measurements were taken in the different constituting elements of the compressor. The study of the mean pressure variations across the operating map showed that the tongue region is a limiting element. Dynamic pressure measurements revealed that the instabilities generated near the inducer when the recirculation is blocked increase the overall instability levels at the compressor outlet and propagating pressure waves starting at the tongue occurred

  1. Internal combustion engine with compound air compression

    Energy Technology Data Exchange (ETDEWEB)

    Paul, M.A.; Paul, A.


    This patent describes an internal combustion engine in combination with a compound air compression system. It comprises: a reciprocator with at least one cylinder, at least one piston reciprocal in the cylinder and a combustion chamber formed in substantial part by portions of the piston and cylinder, the reciprocator having a drive shaft; a rotary compressor having a drive shaft mechanically coupled to the drive shaft of the reciprocator, the rotary compressor having a Wankel-type, three-lobe, epitrochiodal configuration sides having a conduit conjected to the reciprocator for supplying compressed air to the reciprocator; a turbocharged with a gas turbine and a turbocompressor, the turbocompressor having an air conduit connected to the expander side of the rotary compressor; and a bypass conduit with a valve means connecting the turbocharger to the reciprocator for supplying compressed air directly to the reciprocator wherein the drive shaft of the reciprocator and the drive shaft of the compressor have connecting means for transmitting mechanical energy to the reciprocator at mid to high operating speeds of the engine when the turbocharge supplies compressed air to the rotary compressor and, at least in part, drives the rotary compressor.

  2. Prediction of Cracking Gas Compressor Performance and Its Application in Process Optimization

    Institute of Scientific and Technical Information of China (English)

    李绍军; 李凤


    Cracking gas compressor is usually a centrifugal compressor. The information on the performance of a centrifugal compressor under all conditions is not available, which restricts the operation optimization for compressor. To solve this problem, two back propagation (BP) neural networks were introduced to model the performance of a compressor by using the data provided by manufacturer. The input data of the model under other conditions should be corrected according to the similarity theory. The method was used to optimize the system of a cracking gas compressor by embedding the compressor performance model into the ASPEN PLUS model of compressor. The result shows that it is an effective method to optimize the compressor system.

  3. Kinetic characteristic for a synchronal rotary compressor

    Institute of Scientific and Technical Information of China (English)

    Qu Zongchang; Feng Jianmei; Zhou Hui; Yang Hua


    An angular speed, acceleration and tangential leakage of a synchronal rotary compressor in which both bladed rotor and a cylinder are discussed. The calculation formulae of revolving speed of cylinder and relative speed between the cylinder and bladed rotor are deduced detailedly in this paper. The variation of tangential speed and cylinder acceleration with angular position is investigated for a complete cycle. And some key parameters affected the relative speed are found out, viz, the relative speed depends on the radius of the cylinder and rotary speed of the axis, and the ratio of the cylinder to bladed rotor has not too much influence. It is the theoretic basis of designing and optimizing of structure characteristic of a synchronal rotary compressor. Also a computing formula of leakage related with rotary speed is deduced. It could supply

  4. Analysis and developpment of a Turbivo compressor for MRV applications

    CERN Document Server

    Ksayer, Elias Boulawz


    The mechanical vapor recompression is an efficient process to decrease energy consumption of drying processes. In order to use the mechanical vapor recompression (MVR) in residential clothe dryers, the volumetric Turbivo technology is used to design a dry water vapor compressor. The Turbivo volumetric machine is composed mainly of a rotor with one blade, a stator, and a mobile oscillating thrust. The advantages of Turbivo(R) technology are the absence of contact between rotor and stator as well as the oil-free operation. A model of the Turbivo compressor, including kinematic, dynamic, and thermodynamic analysis is presented. The compressor internal tightness is ensured by a surface treatment of the compressor components. Using the model, a water vapor Turbivo compressor of 12m3/h and compression ratio of 5 has been sized and realized. The compressor prototype will be tested on a dedicated test bench to characterize its volumetric and isentropic efficiencies.

  5. Correlating compressor and turbine costs with thermodynamic properties for CAES power plants

    Energy Technology Data Exchange (ETDEWEB)

    Vadasz, P.; Weiner, D.


    Compressed air energy storage (CAES) is a technology that converts excess base load energy into stored pneumatic energy by means of a compressor for a later release through a turbine as premium peaking power. The CAES system consists of a modified gas turbine combined with an underground storage reservoir. Since 1978, such a power plant has operated successfully in Huntorf, West Germany. Others are in construction throughout the world, the largest being constructed in Donbas, Soviet Union (1050 MW). CAES is more economic with respect to other energy storage facilities due to its relatively low installation cost, short construction time, and high reliability. However, since the number of CAES plants all over the world is still small, it is essential for plant planning and optimization to evaluate normative functions for the turbine and compressor cost. The components costs are evaluated from their thermodynamic and turbo-aerodynamic properties, enabling evaluation of the optimal plant parameters.

  6. Real-time trend monitoring of gas compressor stations

    Energy Technology Data Exchange (ETDEWEB)

    Van Hardeveld, T. (Nova, an Alberta Corp., AB (Canada))


    The authors' company has developed a machinery health monitoring system (MHealth) for short-term and long-term historical trending and analysis of data from its 40 gas compressor stations. The author discusses the benefits of real-time trending in troubleshooting operations, in preventative maintenance scheduling and cites specific applications in the startup operations of several new gas compressor/centrifugal compressor units.

  7. Optimization of a scroll compressor for liquid flooding


    Bell, Ian; Groll, Eckhard; Braun, James; King, Galen; W. Travis, Horton


    In two companion papers, simulation models for the working processes of liquid-flooded scroll compressors and expanders have been developed and validated against experimental data. In this study, analytic models are presented for the modes of irreversibility generation in the liquid-flooded scroll compressor including built-in volume ratio maladjustment, pressure drop and leakage. A thermodynamic model is used to derive the ideal volume ratio for a liquid-flooded compressor, which is higher t...

  8. An alternative compressor. A study; Alternativ kompressor. En udredning

    Energy Technology Data Exchange (ETDEWEB)

    Dall, O.; Jensen, F.; Danig, P.O.; Ritchie, E.; Kierkegaard, P.


    A linear compressor would be suitable for refrigerating systems with small effect. A computerized control system can be used to control the speed of a linear engine. A new compressor/engine with much improved energy efficiency can be designed to operate oil-free. The novel design of a compressor with smaller piston displacement is smaller than the existing models and thus more suitable for the future refrigerators. (EG) EFP-97. 71 refs.

  9. Small variable speed hermetic reciprocating compressors for domestic refrigerators

    DEFF Research Database (Denmark)

    Rasmussen, Bjarne D.


    compressors are compared with experimental results obtained in a compressor test bench. The influence of speed on compressor performance is discussed with focus on valve modelling and internal thermal phenomena. Further plans for development and validation of the model as well as experimental investigations......This paper contains both a theoretical and experimental investigation of some of the fundamental characteristics of a smal variable speed hermetic reciprocating compressor intended for application in domestic refrigeration. The results of a previously published simulation model for variable speed...

  10. Helium compressors for closed-cycle, 4.5-Kelvin refrigerators (United States)

    Hanson, T. R.


    An improved helium compressor for traveling-wave maser and closed-cycle refrigerator systems was developed and is currently being supplied to the DSN. This new 5-hp compressor package is designed to replace the current 3-hp DSN compressors. The new compressor package was designed to retrofit into the existing 3-hp compressor frame and reuse many of the same components, therefore saving the cost of documenting and fabricating these components when implementing a new 5-hp compressor.

  11. Axial and Centrifugal Compressor Mean Line Flow Analysis Method (United States)

    Veres, Joseph P.


    This paper describes a method to estimate key aerodynamic parameters of single and multistage axial and centrifugal compressors. This mean-line compressor code COMDES provides the capability of sizing single and multistage compressors quickly during the conceptual design process. Based on the compressible fluid flow equations and the Euler equation, the code can estimate rotor inlet and exit blade angles when run in the design mode. The design point rotor efficiency and stator losses are inputs to the code, and are modeled at off design. When run in the off-design analysis mode, it can be used to generate performance maps based on simple models for losses due to rotor incidence and inlet guide vane reset angle. The code can provide an improved understanding of basic aerodynamic parameters such as diffusion factor, loading levels and incidence, when matching multistage compressor blade rows at design and at part-speed operation. Rotor loading levels and relative velocity ratio are correlated to the onset of compressor surge. NASA Stage 37 and the three-stage NASA 74-A axial compressors were analyzed and the results compared to test data. The code has been used to generate the performance map for the NASA 76-B three-stage axial compressor featuring variable geometry. The compressor stages were aerodynamically matched at off-design speeds by adjusting the variable inlet guide vane and variable stator geometry angles to control the rotor diffusion factor and incidence angles.

  12. 46 CFR 154.534 - Cargo pumps and cargo compressors. (United States)


    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo pumps and cargo compressors. 154.534 Section 154.534 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES... Equipment Cargo and Process Piping Systems § 154.534 Cargo pumps and cargo compressors. Cargo pumps...

  13. Experimental Study for Reduction of Noises and Vibrations in Hermetic Type Compressor (United States)

    Sano, Kiyoshi; Kawahara, Sadao; Akazawa, Teruyuki; Ishii, Noriaki

    A brushless DC motor with a permanent magnet rotor has been adopted for a scroll compressor for domestic-use air-conditioners because of a demand for compressor high efficiency. A waveform of the driving voltage in the inverter power supply unit is chopped by the PWM signal. Its duty ratio is increased/decreased to control the DC voltage in order to provide a wide range of rotation frequencies for the compressor. The driving voltage includes the carrier frequency and its harmonic components, which produce an electro-magnetic force in the moter, resulting in high electro-magnetic noise. In the present report, the author clarifies the relationships between the noise and the waveform of driving voltage and frequency response function of the motor. A method to improve the frequency response function by changing the stator shape in order to reduce electro-magnetic noise is presented. Subsequently, the influence on electro-magnetic noise from the waveform of driving voltage is examined. Furthermore, the electro-magnetic noises during inverter driving of an induction motor are presented.

  14. Fuel efficiency, availability and compressor station configuration

    Energy Technology Data Exchange (ETDEWEB)

    Lubomirsky, Matt; Kurz, Rainer [Solar Turbines Inc., San Diego, CA (United States); Klimov, Pavel [Intergas Central Asia, Astana (Kazakhstan)


    Compressor stations play a very important role in the success of a gas pipeline design and a careful selection of centrifugal compressors and drivers are key aspects for the success of the project. The state of the art design available today for this equipment provides overall high thermodynamic performance and consequently minimizes installed power requirements and energy usage with significant savings on operating expenses during the economic life of the project For any application of machinery in a pipeline compression station, one of the key questions to answer is the number of units to install to meet the flow requirements of the pipeline. Depending on the load profile of the pipeline, the answers may look different. Other factors to consider include the fact that gas turbines can produce a significant amount of additional power at lower ambient temperatures. So, even for constant load of the pipeline, the relative load of the driver changes. In this paper, a typical transcontinental pipeline with multiple compressor stations is evaluated. The determination of the exact hydraulic behavior of the pipeline is part of the modeling effort. The site ambient conditions, with a significant swing in ambient temperatures are considered. The issue discussed in this paper evolves around the availability that can be achieved with various configurations, based on actually achieved reliability and availability numbers. The other large impact on operating costs, fuel consumption will be discussed. Here, the choice of the number of installed units has a distinct impact on annual fuel consumption, as well as the capacity of the pipeline during various scenarios. (author)

  15. Market Investigation for Surface Supplied Diving Air Compressors (United States)


    is anodized for extended service life. The checking area is in the bottom segment and the unloading area is in the top segment . A small aluminum...oiston with a teflon ring rides through middle segment to insure maximum valve efficiency. / J.d M aPC40 Product Data: L-Series PD002 Page: 3 of 4 LSERIES...hohe Luft- und Gasdrucke * opkeBu lseihsGwct sowvie M~r Boosterbetrieb auf den Markt o Horizontal angeordnete Zylinder mit stelfem Joch zur

  16. Compressor Calorimeter Test of R-410A Alternatives R-32, DR-5, and L-41a

    Energy Technology Data Exchange (ETDEWEB)

    Shrestha, Som S [ORNL; Mahderekal, Isaac [ORNL; Sharma, Vishaldeep [ORNL; Abdelaziz, Omar [ORNL


    As a contribution to the AHRI Low-GWP Alternative Refrigerants Evaluation Program (AREP), this study compares performance of alternative refrigerants R32, DR-5, and L-41A to that of refrigerant R-410A (baseline) in a scroll compressor designed for air-conditioning and heat pump applications. Compressor calorimeter tests were performed to evaluate the performance of the lower-GWP alternative refrigerants in place of the common refrigerant R-410A in a 36,000 Btu/hr compressor calorimeter using a compressor having a nominal rated capacity of 21,300 Btu/hr. Tests were conducted over a suction dew point temperature range of 10 F to 55 F in 5 F increments and a discharge dew point temperature range of 70 F to 140 F in 10 F increments. All the tests were performed with 20 F superheat, 40 F superheat and 65 F suction temperature. A liquid subcooling level of 15 F was maintained for all the test conditions. The tests showed that performance of these three lower-GWP alternative refrigerants is comparable to that of R-410A. For the 20 F superheat and 15 F subcooling test conditions, EERs of R32, DR-5, and L-41A were 90% to 99%, 96% to 99%, and 94% to 101%, respectively, compared to that of R-410A. Similarly, cooling capacities of R32, DR-5, and L-41A were 98% to 103%, 92% to 96%, and 84% to 92%, respectively, compared to that of R-410A.

  17. Factory acceptance of the compressor skids at Samifi-Babcock. All pictures show the second stage compressor skid.

    CERN Multimedia

    G. Perinic


    Most recent pictures taken during the factory acceptance of the compressor skids at Samifi-Babcock. All pictures show the second stage compressor skid. Picture two was taken during the leak tests and shows all the pockets around flanges and valves.

  18. High Efficiency Centrifugal Compressor for Rotorcraft Applications (United States)

    Medic, Gorazd; Sharma, Om P.; Jongwook, Joo; Hardin, Larry W.; McCormick, Duane C.; Cousins, William T.; Lurie, Elizabeth A.; Shabbir, Aamir; Holley, Brian M.; Van Slooten, Paul R.


    The report "High Efficiency Centrifugal Compressor for Rotorcraft Applications" documents the work conducted at UTRC under the NRA Contract NNC08CB03C, with cost share 2/3 NASA, and 1/3 UTRC, that has been extended to 4.5 years. The purpose of this effort was to identify key technical barriers to advancing the state-of-the-art of small centrifugal compressor stages; to delineate the measurements required to provide insight into the flow physics of the technical barriers; to design, fabricate, install, and test a state-of-the-art research compressor that is representative of the rear stage of an axial-centrifugal aero-engine; and to acquire detailed aerodynamic performance and research quality data to clarify flow physics and to establish detailed data sets for future application. The design activity centered on meeting the goal set outlined in the NASA solicitation-the design target was to increase efficiency at higher work factor, while also reducing the maximum diameter of the stage. To fit within the existing Small Engine Components Test Facility at NASA Glenn Research Center (GRC) and to facilitate component re-use, certain key design parameters were fixed by UTRC, including impeller tip diameter, impeller rotational speed, and impeller inlet hub and shroud radii. This report describes the design effort of the High Efficiency Centrifugal Compressor stage (HECC) and delineation of measurements, fabrication of the compressor, and the initial tests that were performed. A new High-Efficiency Centrifugal Compressor stage with a very challenging reduction in radius ratio was successfully designed, fabricated and installed at GRC. The testing was successful, with no mechanical problems and the running clearances were achieved without impeller rubs. Overall, measured pressure ratio of 4.68, work factor of 0.81, and at design exit corrected flow rate of 3 lbm/s met the target requirements. Polytropic efficiency of 85.5 percent and stall margin of 7.5 percent were

  19. Supercharging an internal combustion engine by aid of a dual-rotor bi-flux axial compressor (United States)

    Grǎdinariu, Andrei Cristian; Mihai, Ioan


    Internal combustion engines can be supercharged in order to enhance their performances [1-3]. Engine power is proportional to the quantity of fresh fluid introduced into the cylinder. At present, the general tendency is to try to obtain actual specific powers as high as possible, for as small as possible cylinder capacity, without increasing the generated pollution hazards. The present paper investigates the impact of replacing a centrifugal turbo-compressor with an axial double-rotor bi-flux one [4]. The proposed method allows that for the same number of cylinders, an increase in discharged airflow, accompanied by a decrease in fuel consumption. Using a program developed under the MathCad environment, the present work was aimed at studying the way temperature modifies at the end of isentropic compression under supercharging conditions. Taking into account a variation between extreme limits of the ambient temperature, its influence upon the evolution of thermal load coefficient was analyzed considering the air pressure at the compressor cooling system outlet. This analysis was completed by an exergetical study of the heat evacuated through cylinder walls in supercharged engine conditions. The conducted investigation allows verification of whether significant differences can be observed between an axial, dual-rotor, bi-flux compressor and centrifugal compressors.


    Institute of Scientific and Technical Information of China (English)


    A new compressor thermodynamic model is set up. Artificial neural networks(ANN) which have self-adjusting functions are adopted to calculate volumetric efficiency and electrical efficiency of a compressor. The new compressor model composed of the theoretical model and ANN reaches more precise results than traditional ones. Furthermore, the new compressor model is of better flexibility in a large scale.

  1. Cooling Performance Characteristics on Mobile Air-Conditioning System for Hybrid Electric Vehicles


    Ho-Seong Lee; Moo-Yeon Lee


    This study investigates the cooling performance characteristics of the mobile air-conditioning system using R744 (CO2) for the hybrid electric vehicle as an alternative to both the R-134a and the conventional air-conditioning system. The developed air-conditioning system is operated with an electric driven compressor in the battery driving mode and a belt driven compressor in the engine driving mode. The cooling performance characteristics of the developed system have been analyzed by experim...

  2. Solid deposition in the ITER cryogenic viscous compressor (United States)

    Zhang, Dongsheng; Miller, Franklin K.; Pfotenhauer, John M.


    A transient model for the ITER cryogenic viscous compressor (CVC) is presented. The CVC is designed to separate hydrogen isotopes from helium in the gas-mixture exhaust from the ITER torus. During their residence in the CVC, hydrogen isotopes are captured along the pump wall while helium flows through. The CVC thereby provides the first stage of helium compression. The transient model characterizes the transport phenomena (species, momentum, and energy) that occur in the CVC. The numerical results are compared with experimental data from a scaled down test of the ITER CVC using pure hydrogen. Although the model has been developed for a hydrogen-helium mixture, it is simplified here in order to compare with the experimental data. The transient model, along with other numerical models we have developed, provide guidance for the design and optimization of the ITER CVC. The model can also be a useful tool or a reference for similar analyses, such as those for cryogenic carbon capture and air ingress in vacuum isolated cryogenic vessels.

  3. CFD Analysis of a supercritical carbon dioxide compressor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong Gu; Lee, Jeong Ik; Ahn, Yoon Han; Lee, Jek Young; Cha, Jae Eun; Addad, Yacine [KAIST, Daejeon (Korea, Republic of)


    The supercritical carbon dioxide Brayton cycle is considered as an attractive cycle for the next generation nuclear systems. It was identified that the compressor can achieve very small compressing work as operating conditions become closer to the critical point. Smaller amount of input work contributes to the enhancement of overall net cycle efficiency. Comparing to traditional water vapor cycle and helium cycle, the S CO{sup 2} cycle has relatively much less volume and component size. Therefore, S CO{sup 2} cycle can be used for many purposes such as nuclear ship propulsion where volume requirement is strict, or a small nuclear reactor when it is constructed on geographically limited area One of the main factors for determining the supercritical Brayton cycle efficiency is the performance of turbomachineries. Many research organizations already obtained experimental data of S CO{sup 2} cycle turbomachineries, but the amount of data is still limited. Our research team is conducting a S CO{sup 2} compressor test to obtain fundamental data for advanced compressor design and measure the performance of the compressor near the critical point. The S CO{sup 2} compressor testing loop is specially designed to test main compressor of the loop. The S CO{sup 2} fluid shows the properties of gases and liquids at the same time, but its behavior is closer to the liquid rather than gas near the critical point. Therefore, we are performing compressor test with canned motor pump which is unique from other previous studies.

  4. Core compressor exit stage study. 1: Aerodynamic and mechanical design (United States)

    Burdsall, E. A.; Canal, E., Jr.; Lyons, K. A.


    The effect of aspect ratio on the performance of core compressor exit stages was demonstrated using two three stage, highly loaded, core compressors. Aspect ratio was identified as having a strong influence on compressors endwall loss. Both compressors simulated the last three stages of an advanced eight stage core compressor and were designed with the same 0.915 hub/tip ratio, 4.30 kg/sec (9.47 1bm/sec) inlet corrected flow, and 167 m/sec (547 ft/sec) corrected mean wheel speed. The first compressor had an aspect ratio of 0.81 and an overall pressure ratio of 1.357 at a design adiabatic efficiency of 88.3% with an average diffusion factor or 0.529. The aspect ratio of the second compressor was 1.22 with an overall pressure ratio of 1.324 at a design adiabatic efficiency of 88.7% with an average diffusion factor of 0.491.

  5. Modeling and control of surge and rotating stall in compressors

    Energy Technology Data Exchange (ETDEWEB)

    Gravdahl, Jan Tommy


    Compressors are used in power generation and a variety of other applications. This thesis contains new results in the field of modeling and control of rotating stall and surge in compressors. A close coupled valve is included in the Moore-Greitzer compression system model and controllers for both surge and rotating stall is derived using backstepping. Disturbances, constant and time varying, are then taken into account, and non-linear controllers are derived. Stability results are given. Then, passivity is used to derive a simple surge control law for the closed coupled valve. This propositional control law is shown to stabilize the system even in the presence of time varying disturbances in mass flow and pressure. A novel model for an axial compression system with non-constant compressor speed is derived by extending the Moore-Greitzer model. Rotating stall and surge is studied in connection with acceleration of the compressor. Finally, a model for a centrifugal compression system with time varying compressor speed is derived. The variable speed compressor characteristic is derived based on energy losses in the compressor components. Active control of surge in connection with varying speed is studied. Semi-global exponential stability of the compression system with both surge and speed control is proven. 103 refs., 38 figs., 5 tabs.

  6. Dental Compressed Air Systems. (United States)


    compressor ex- cept that the piston rings are made of a low friction material (usually a Teflon- composite ) The piston walls are oil-less and all friction... descal - ing. The water-cooled models are smaller, more efficient, and cause less heating of room air. Water-cooled aftercoolers must have an...dry to a dew point of -400C (-400 F). It has high adsorption capacity. (b) Silica Gel , which must be protected from liquid (usually by a layer of

  7. Internal hysteresis experienced on a high pressure syn gas compressor (United States)

    Zeidan, F. Y.


    A vibration instability phenomenon experienced in operating high pressure syn gas centrifugal compressors in two ammonia plants is described. The compressors were monitored by orbit and spectrum analysis for changes from baseline readings. It is found that internal hysteresis was the major destabilizing force; however, the problem was further complicated by seal lockup at the suction end of the compressor. A coupling lockup problem and a coupling fit problem, which frettage of the shaft, are also considered as contributors to the self excited vibrations.

  8. Expert system for compressor maintenance support; Sistema especialista para apoio a manutencao de compressores

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Jonny Carlos da [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica; Caletti, Luciano [KEOHPS - Knowledge Engineering on Hydraulic and Pneumatic System, SC (Brazil); Luna, Paulo de T.M. [Universidade Regional de Blumenau - FURB, SC (Brazil)


    The performance of critical machines in industrial processes, such as compressors used in industrial plants, is fundamental for overall company operation. In this context, it becomes strategic the application of methods and tools to support the operation and maintenance of the most relevant process equipment. Among these computational tools are the Expert Systems, which aim to emulate the decision making process of human experts in a specific knowledge domain. In Oil and Gas domain, an example of such tools is the SEGRED project, which combines expert system techniques with dynamic simulation of transport and distribution natural gas networks. The SECOMP project, Expert System for Compressor Maintenance, is considered a spin-off of the SEGRED. Its objective is to develop an expert system to support maintenance activities, aiming to increase reliability, improve performance and reduce maintenance and operational costs. This article presents the first phase of the SECOMP project, which is related to the development of an expert system prototype for corrective maintenance of natural gas reciprocating compressors. The paper discusses the context of this knowledge domain, the prototype development and its potential contribution in an industrial environment. (author)

  9. Stabilized Liner Compressor: The Return of Linus (United States)

    Turchi, Peter; Frese, Sherry; Frese, Michael; Mielke, Charles; Hinrichs, Mark; Nguyen, Doan


    To access the lower cost regime of magneto-inertial fusion at megagauss magnetic field-levels requires the use of dynamic conductors in the form of imploding cylindrical shells, aka, liners. Such liner implosions can compress magnetic flux and plasma to attain fusion conditions, but are subject to Rayleigh-Taylor instabilities, both in the launch and recovery of the liner material and in the final few diameters of implosion. These instabilities were overcome in the Linus program at the Naval Research Laboratory, c. 1979, providing the experimentally-demonstrated basis for repetitive operation and leading to an economical reactor concept at low fusion gain. The recent ARPA-E program for low-cost fusion technology has revived interest in this approach. We shall discuss progress in modeling and design of a Stabilized Liner Compressor (SLC) that extends the earlier work to higher pressures and liner speeds appropriate to potential plasma targets. Sponsored by ARPA-E ALPHA Program.

  10. Demonstration of PIV in a Transonic Compressor (United States)

    Wernet, Mark P.


    Particle Imaging Velocimetry (PIV) is a powerful measurement technique which can be used as an alternative or complementary approach to Laser Doppler Velocimetry (LDV) in a wide range of research applications. PIV data are measured simultaneously at multiple points in space, which enables the investigation of the non-stationary spatial structures typically encountered in turbomachinery. Many of the same issues encountered in the application of LDV techniques to rotating machinery apply in the application of PIV. Preliminary results from the successful application of the standard 2-D PIV technique to a transonic axial compressor are presented. The lessons learned from the application of the 2-D PIV technique will serve as the basis for applying 3-component PIV techniques to turbomachinery.

  11. Gas turbine engine with supersonic compressor (United States)

    Roberts, II, William Byron; Lawlor, Shawn P.


    A gas turbine engine having a compressor section using blades on a rotor to deliver a gas at supersonic conditions to a stator. The stator includes one or more of aerodynamic ducts that have converging and diverging portions for deceleration of the gas to subsonic conditions and to deliver a high pressure gas to combustors. The aerodynamic ducts include structures for changing the effective contraction ratio to enable starting even when designed for high pressure ratios, and structures for boundary layer control. In an embodiment, aerodynamic ducts are provided having an aspect ratio of two to one (2:1) or more, when viewed in cross-section orthogonal to flow direction at an entrance to the aerodynamic duct.

  12. 大功率涡旋式氦压缩机系统的研制%Design and study of a scroll helium compressor system

    Institute of Scientific and Technical Information of China (English)

    武义锋; 丁先庚


    A scroll helium compressor system with 5.6KW was introduced in this paper, which was used to supply high pressure helium for the cryocooler with big refrigeration capability. Air - condition compressor was remodelled into a helium compressor to ensure cryocooler to work with a long time and high reliability. Results of the experiment and customer's use show that this helium compressor system is reliable and the study is successful. The big power scroll helium compressor system has being produced and sold now.%介绍了一种5.6KW功率涡旋式氦压缩机系统的研制情况,主要是为了配套大冷量低温制冷机而研制的.采用特有的技术对商用空调压缩机进行了改制,并配套了自行设计的高效可靠的滤油纯化系统,满足了制冷机长期可靠工作的要求.经过运行试验和客户使用,该氦压缩机系统性能是可靠的,研制是成功的,并已小批量生产销售.

  13. A Novel Plasma-Based Compressor Stall Control System Project (United States)

    National Aeronautics and Space Administration — Modern aircraft gas turbine engines utilize highly loaded airfoils in both the compressor and turbine to maximize performance while minimizing weight, cost, and...

  14. The performance of a linear compressor with triangle flexure bearings (United States)

    Zhou, Wenjie; Wang, Longyi; Gan, Zhihua; Qiu, L. M.; Pfotenhauer, John


    This paper reports the performance of a self-fabricated moving coil linear compressor at Zhejiang University. The efficiency of this compressor is tested by an RC load method. From experimental results, its resonant frequency is below 30Hz. When combined with a pulse tube cryocooler (PTC) working at 40Hz, the minimum temperature is 49.1K; the cooling power at 80K is 4.5W, with 540W electricity power input. From the RC load experiment, the maximum efficiency of this compressor is only 37% at 21 Hz. Therefore, this compressor has the potential to drive a three stage PTC at liquid helium temperature by running at 25Hz or lower.

  15. EFRC guidelines for vibrations in reciprocating compressor systems

    NARCIS (Netherlands)

    Eijk, A.


    One of the disadvantages of a reciprocating compressor is that it generates pulsations and vibrations, which, without limitation and proper attention during design, manufacturing, installation and operation, can lead to fatigue failures, inefficiency, capacity limitations and unsafe situations. To j

  16. A Novel Aerodynamic Design Method for Centrifugal Compressor Impeller

    Directory of Open Access Journals (Sweden)

    Mahdi Nili-Ahmadabadi


    Full Text Available This paper describes a new quasi-3D design method for centrifugal compressor impeller. The method links up a novel inverse design algorithm, called Ball-Spine Algorithm (BSA, and a quasi-3D analysis. Euler equation is solved on the impeller meridional plane. The unknown boundaries (hub and shroud of numerical domain are iteratively modified by BSA until a target pressure distribution in flow passage is reached. To validate the quasi-3D analysis code, existing compressor impeller is investigated experimentally. Comparison between the quasi-3D analysis and the experimental results shows good agreement. Also, a full 3D Navier-Stokes code is used to analyze the existing and designed compressor numerically. The results show that the momentum decrease near the shroud wall in the existing compressor is removed by hub-shroud modifications resulting an improvement in performance by 0.6 percent.

  17. Development Of A Centrifugal Hydrogen Pipeline Gas Compressor

    Energy Technology Data Exchange (ETDEWEB)

    Di Bella, Francis A. [Concepts NREC, White River Junction, VY (United States)


    Concepts NREC (CN) has completed a Department of Energy (DOE) sponsored project to analyze, design, and fabricate a pipeline capacity hydrogen compressor. The pipeline compressor is a critical component in the DOE strategy to provide sufficient quantities of hydrogen to support the expected shift in transportation fuels from liquid and natural gas to hydrogen. The hydrogen would be generated by renewable energy (solar, wind, and perhaps even tidal or ocean), and would be electrolyzed from water. The hydrogen would then be transported to the population centers in the U.S., where fuel-cell vehicles are expected to become popular and necessary to relieve dependency on fossil fuels. The specifications for the required pipeline hydrogen compressor indicates a need for a small package that is efficient, less costly, and more reliable than what is available in the form of a multi-cylinder, reciprocating (positive displacement) compressor for compressing hydrogen in the gas industry.

  18. Vapor Compressor Driven Hybrid Two-Phase Loop Project (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project will demonstrate a vapor compressor driven hybrid two-phase loop technology. The hybrid two-phase loop...


    Energy Technology Data Exchange (ETDEWEB)

    Gary D. Bourn; Jess W. Gingrich; Jack A. Smith


    This document is the final report for the ''Advanced Compressor Engine Controls to Enhance Operation, Reliability, and Integrity'' project. SwRI conducted this project for DOE in conjunction with Cooper Compression, under DOE contract number DE-FC26-03NT41859. This report addresses an investigation of engine controls for integral compressor engines and the development of control strategies that implement closed-loop NOX emissions feedback.

  20. Compound fuzzy model for thermal performance of refrigeration compressors

    Institute of Scientific and Technical Information of China (English)


    The fuzzy method is introduced to the calculation of thermal performance of refrigeration compressors. A compound model combining classical thermodynamic theory and fuzzy theory is presented and compared with a simple fuzzy model without classical thermodynamic fundamentals. Case study of refrigeration compressors shows that the compound fuzzy model and the simple fuzzy model are both more efficient than the classical thermodynamic method. However, the compound fuzzy model is of better precision and adaptability.

  1. Internal combustion engine for natural gas compressor operation

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, Christopher; Babbitt, Guy


    This application concerns systems and methods for compressing natural gas with an internal combustion engine. In a representative embodiment, a method is featured which includes placing a first cylinder of an internal combustion engine in a compressor mode, and compressing a gas within the first cylinder, using the cylinder as a reciprocating compressor. In some embodiments a compression check valve system is used to regulate pressure and flow within cylinders of the engine during a compression process.

  2. Longitudinal Beam Diagnostics for the ILC Injectors and Bunch Compressors

    Energy Technology Data Exchange (ETDEWEB)

    Piot, Philippe [Northern Illinois U.; Bracke, Adam [Northern Illinois U.; Demir, Veysel [Northern Illinois U.; Maxwell, Timothy [Fermilab; Rihaoui, Marwan [Argonne; Jing, Chunguang [Euclid Techlabs, Solon; Power, John [Argonne


    We present a diagnostics suite and analyze techniques for setting up the longitudinal beam dynamics in ILC e⁻ injectors and e⁺ and e⁻ bunch compressors. Techniques to measure the first order moments and recover the first order longitudinal transfer map of the injector's intricate bunching scheme are presented. Coherent transition radiation diagnostics needed to measure and monitor the bunch length downstream of the ~5 GeV bunch compressor are investigated using a vector diffraction model.

  3. Hyper dispersion pulse compressor for chirped pulse amplification systems (United States)

    Barty, Christopher P. J.


    A grating pulse compressor configuration is introduced for increasing the optical dispersion for a given footprint and to make practical the application for chirped pulse amplification (CPA) to quasi-narrow bandwidth materials, such as Nd:YAG. The grating configurations often use cascaded pairs of gratings to increase angular dispersion an order of magnitude or more. Increased angular dispersion allows for decreased grating separation and a smaller compressor footprint.

  4. Cooling Effect Improvement by Dimensional Modification of Annular Fins in Two Stage Reciprocating Compressor

    Directory of Open Access Journals (Sweden)

    Mr. Ashish D. Vasiyar,


    Full Text Available The Reciprocating Compressor fins are made from Aluminum alloy and it is provided for increase in contact area in convective heat transfer. Air cooling is a method of dissipating heat It works by making the object to be cooled have a larger surface area or have an increased flow of air over its surface. a fin is a surface that extends from an object to increase the rate of heat transfer to or from the environment by increasing convection. The aim of present work study is to prepare a finite element model of fin. The result of finite element model will be verified with experimental work with thermocouple. After comparing results of FEA model we can modify boundary condition, material shape & size for improvement in efficiency & cooling rate. It is possible to find optimum solution with FEA package ANSYS 14 used for modeling and analysis. Effectiveness of fin can be improved by changing geometry of fin. So after increase effectiveness it can increase cooling rate and minimize the time for cooling process of Reciprocating compressor. Aim of this work is increase effectiveness of the fin for best performance.

  5. Helium compressor for GM and pulse-tube expanders (United States)

    Longsworth, R. C.


    A new compressor system has been developed for cooling MRI magnets which has more displacement than the present compressor. By increasing the displacement from 2.9 L/s to 5.2 L/s at 60 Hz it is possible to provide more refrigeration at lower temperatures with both GM and Pulse-tube expanders. The 2.9 L/s compressor is a rolling piston type, which is cooled by water circulating through tubes bonded to the outside of the compressor shell. The 5.2 L/s compressor is a scroll type that is cooled by circulating oil to an external heat exchanger. One of the key features of the design is an oil removal system that enables the adsorber replacement interval to be increased to 5 years. A diagnostic module is incorporated in the control circuit to alert the user to an abnormal condition and show the reason for a shut down if it occurs. This paper describes essential design features and the extensive testing that has been done to characterize the compressor over a wide range of operating conditions including extremes that it might experience.

  6. Design and Characterization of a Centrifugal Compressor Surge Test Rig

    Directory of Open Access Journals (Sweden)

    Kin Tien Lim


    Full Text Available A detailed description of a new centrifugal compressor surge test rig is presented. The objective of the design and development of the rig is to study the surge phenomenon in centrifugal compression systems and to investigate a novel method of surge control by active magnetic bearing servo actuation of the impeller axial tip clearance. In this paper, we focus on the design, initial setup, and testing of the rig. The latter two include the commissioning of the rig and the experimental characterization of the compressor performance. The behavior of the compressor during surge is analyzed by driving the experimental setup into surge. Two fundamental frequencies, 21 Hz and 7 Hz, connected to the surge oscillation in the test rig are identified, and the observed instability is categorized according to the intensity of pressure fluctuations. Based on the test results, the excited pressure waves are clearly the result of surge and not stall. Also, they exhibit the characteristics of mild and classic surge instead of deep surge. Finally, the change in the compressor performance due to variation in the impeller tip clearance is experimentally examined, and the results support the potential of the tip clearance modulation for the control of compressor surge. This is the first such demonstration of the feasibility of surge control of a compressor using active magnetic bearings.

  7. Transient characteristic of reciprocating compressors in household refrigerators

    Energy Technology Data Exchange (ETDEWEB)

    Porkhial, S.; Khastoo, B. [Amirkabir University, Tehran (Iran). Dept. of Mechanical Engineering; Modarres Razavi, M.R. [Ferdowsi University, Mashhad (Iran). Dept. of Mechanical Engineering


    Reduction in energy consumption associated with household appliances is a challenging subject. One of the appliances with great contribution in energy consumption is the household refrigerators [1 and 2]. Among the different components of a refrigerator, the compressor has the most effect on system energy consumption. A knowledge of the transient performance of compressors is vital for reduction of energy consumption and improving the overall performance of a refrigerator. In this paper the M7 model of 1/5 hp Nicchi compressor belonging to 12 ft{sup 3} refrigerators with refrigerant R12 is selected as a sample and different tests are carried out to determine its transient behavior. Based on the analysis of experimental results, the governing equations and the simulation program of transient behavior have been developed. Good agreement between theoretical and experimental results means that the simulation model could be an appropriate tool to study the transient behavior of reciprocating compressors in different conditions. Analysis of predicted and experimental results shows that refrigerators consume more power in the transient mode as compared to the steady mode, therefore shortening the transient period can lower the energy consumption of the system. Also an isentropic assumption for the hermetic compressor is not a correct assumption, especially for the transient mode. With appropriate design of compressor inlet which locates it near to the suction valve, the energy efficiency will be improved. (author)

  8. The new performance calculation method of fouled axial flow compressor. (United States)

    Yang, Huadong; Xu, Hong


    Fouling is the most important performance degradation factor, so it is necessary to accurately predict the effect of fouling on engine performance. In the previous research, it is very difficult to accurately model the fouled axial flow compressor. This paper develops a new performance calculation method of fouled multistage axial flow compressor based on experiment result and operating data. For multistage compressor, the whole compressor is decomposed into two sections. The first section includes the first 50% stages which reflect the fouling level, and the second section includes the last 50% stages which are viewed as the clean stage because of less deposits. In this model, the performance of the first section is obtained by combining scaling law method and linear progression model with traditional stage stacking method; simultaneously ambient conditions and engine configurations are considered. On the other hand, the performance of the second section is calculated by averaged infinitesimal stage method which is based on Reynolds' law of similarity. Finally, the model is successfully applied to predict the 8-stage axial flow compressor and 16-stage LM2500-30 compressor. The change of thermodynamic parameters such as pressure ratio, efficiency with the operating time, and stage number is analyzed in detail.

  9. The New Performance Calculation Method of Fouled Axial Flow Compressor

    Directory of Open Access Journals (Sweden)

    Huadong Yang


    Full Text Available Fouling is the most important performance degradation factor, so it is necessary to accurately predict the effect of fouling on engine performance. In the previous research, it is very difficult to accurately model the fouled axial flow compressor. This paper develops a new performance calculation method of fouled multistage axial flow compressor based on experiment result and operating data. For multistage compressor, the whole compressor is decomposed into two sections. The first section includes the first 50% stages which reflect the fouling level, and the second section includes the last 50% stages which are viewed as the clean stage because of less deposits. In this model, the performance of the first section is obtained by combining scaling law method and linear progression model with traditional stage stacking method; simultaneously ambient conditions and engine configurations are considered. On the other hand, the performance of the second section is calculated by averaged infinitesimal stage method which is based on Reynolds’ law of similarity. Finally, the model is successfully applied to predict the 8-stage axial flow compressor and 16-stage LM2500-30 compressor. The change of thermodynamic parameters such as pressure ratio, efficiency with the operating time, and stage number is analyzed in detail.

  10. Operating experiences and test results of six cold helium compressors (United States)

    Brown, D. P.; Gibbs, R. J.; Schlafke, A. P.; Sondericker, J. H.; Wu, K. C.

    Three small and three large cold helium centrifugal compressors have been operated at Brookhaven National Laboratory between 1981 and 1986. The three small cold compressors have been installed on a 1000 W refrigerator for testing a string of superconducting magnets and for R and D purposes. The three large units are components of the BNL 24.8 KW refrigerator to be used to provide cooling for the RHIC project. These compressors are used either to circulate a large amount of supercritical helium through a group of magnets or to pump on the helium bath to reduce temperature in the system. One small circulating compressor tested employs tilting-pad gas bearings and is driven by a DC motor. The two small cold vacuum pumps tested use oil bearings and are driven by oil turbines. The three large oil-bearing cold compressors are driven by DC motors through a gear box. A unique feature of the large vacuum pump is the combination of two pumps with a total of four stages on the same shaft. The adiabatic efficiencies are found to be 57% for the large vacuum pumps and close to 50% for the large circulating compressor. Good overall reliability has been experienced.

  11. Insulation system in an integrated motor compressor

    Energy Technology Data Exchange (ETDEWEB)

    Sihvo, V.


    A high-speed and high-voltage solid-rotor induction machine provides beneficial features for natural gas compressor technology. The mechanical robustness of the machine enables its use in an integrated motor-compressor. The technology uses a centrifugal compressor, which is mounted on the same shaft with the high-speed electrical machine driving it. No gearbox is needed as the speed is determined by the frequency converter. The cooling is provided by the process gas, which flows through the motor and is capable of transferring the heat away from the motor. The technology has been used in the compressors in the natural gas supply chain in the central Europe. New areas of application include natural gas compressors working at the wellheads of the subsea gas reservoir. A key challenge for the design of such a motor is the resistance of the stator insulation to the raw natural gas from the well. The gas contains water and heavy hydrocarbon compounds and it is far harsher than the sales gas in the natural gas supply network. The objective of this doctoral thesis is to discuss the resistance of the insulation to the raw natural gas and the phenomena degrading the insulation. The presence of partial discharges is analyzed in this doctoral dissertation. The breakdown voltage of the gas is measured as a function of pressure and gap distance. The partial discharge activity is measured on small samples representing the windings of the machine. The electrical field behavior is also modeled by finite element methods. Based on the measurements it has been concluded that the discharges are expected to disappear at gas pressures above 4 - 5 bar. The disappearance of discharges is caused by the breakdown strength of the gas, which increases as the pressure increases. Based on the finite element analysis, the physical length of a discharge seen in the PD measurements at atmospheric pressure was approximated to be 40 - 120 mum. The chemical aging of the insulation when exposed to raw

  12. Efficiency of Compressed Air Energy Storage


    Elmegaard, Brian; Brix, Wiebke


    The simplest type of a Compressed Air Energy Storage (CAES) facility would be an adiabatic process consisting only of a compressor, a storage and a turbine, compressing air into a container when storing and expanding when producing. This type of CAES would be adiabatic and would if the machines were reversible have a storage efficiency of 100%. However, due to the specific capacity of the storage and the construction materials the air is cooled during and after compression in practice, making...

  13. Lubricants for HFC-134a Compatible Rotary Compressors (United States)

    Takaichi, Kenji; Sakai, Hisakazu

    In replacing CFC-12 with HFC-134a for refrigerator compressors, the compatibility with lubricating oil, and lubrication in general, are of major concern. HFC-134a dose not have adequate solubility with current lubricating oils because of its molecular structure. Current oils also do not provide enough lubricating action when using HFC-134a. A new oil and new materials have to be utilized in order to use HFC-134a. Developing a new lubricating oil involved numerous tests of different combinations of many polyolester synthetic oils and additives. One of the pre-evaluated methods was pursued via sealed tube tests. Lubricated parts were selected by studies involving a plane-on-roller type of wear test machine and by analyzing the traces of acid material commonly created during the lubricating action. The matrices of new lubricating oils and new lubricated materials were estimated based on durability tests conducted on compressors and refrigerators. Results showed that polyolester synthetic oils having a low total acid value and including certain quantities of additives did not break down into a tar-like substance and they did not produce composite particles in the operating compressors and refrigerators. The study also found that ceramics and anti-corrosion alloy steel possessed good adrasion-reducing qualities. Based on our evaluation, we will implement compressor reliability tests and apply HFC-134a to rotary compressors for refrigerators.

  14. A high pressure ratio DC compressor for tactical cryocoolers (United States)

    Chen, Weibo; Cameron, Benjamin H.; Zagarola, Mark V.; Narayanan, Sri R.


    A high pressure ratio DC compressor is a critical component for many cryocooler cycles. Prior research has focused on the adaptation of commercial compressor technology (scroll, screw, linear with rectification valves, and regenerative) for use in cryogenic applications where long-life and oil-free (i.e., volatile contamination free) are unique requirements. In addition, many cryocooler applications are for cooling imaging instruments making low vibration an additional requirement. Another candidate compressor technology has emerged from the fuel cell industry. Proton Exchange Membranes (PEMs) are used in fuel cells to separate reactants and transport protons, and these capabilities may be used in cryocoolers to compress hydrogen from low to high pressure. A particular type of PEM utilizing an anhydrous membrane forms the basis of a solid-state cryocooler. Creare has been investigating the use of PEM compressors for low temperature Joule-Thomson and dilution cryocoolers. These cryocoolers have no moving parts, can operate at temperatures down to nominally 23 K, produce no vibration, and are low cost. Our work on the cycle optimization, cryocooler design, and development and demonstration of the compressor technology is the subject of this paper.

  15. Flexure bearing compressor in the one watt linear (OWL) envelope (United States)

    Rühlich, I.; Mai, M.; Wiedmann, Th.; Rosenhagen, C.


    For high performance IR detectors the split linear cooler is a preferred solution. High reliability, low induced vibration and low audible noise are major benefits of such coolers. Today, most linear coolers are qualified for MTTF of 8,000h or above. It is a strong customer desire to further reduce the maintenance costs on system level with significantly higher cooler lifetime. Increased cooler MTTF figures are also needed for IR applications with high lifetime requirements like missile warning applications, border surveillance or homeland security applications. AIM developed a Moving Magnet Flexure Bearing compressor to meet a MTTF of minimum 20,000h. The compressor has a full flexure bearing support on both sides of the driving mechanism. In the assembly process of the compressor an automated alignment process is used to achieve the necessary accuracy. Thus, side-forces on the pistons are minimized during operation, which significantly reduces the wear-out. In order to reduce the outgassing potential most of the internal junctions are welded and the use of all non-metallic components is minimized. The outline dimensions comply with the SADA2 requirements in length and diameter. Further, when operated with a 1/2" SADA type coldfinger, the cooler meets all specified performance data for SADA2. The compressor can be combined with different Stirling type coldfingers and also with the AIM Pulse Tube coldfinger, which gives increased lifetime potential up to 50,000h MTTF. Technical details and performance data of the new compressor are shown.

  16. Turbo-alternator-compressor design for supercritical high density working fluids (United States)

    Wright, Steven A.; Fuller, Robert L.


    Techniques for generating power are provided. Such techniques involve a thermodynamic system including a housing, a turbine positioned in a turbine cavity of the housing, a compressor positioned in a compressor cavity of the housing, and an alternator positioned in a rotor cavity between the turbine and compressor cavities. The compressor has a high-pressure face facing an inlet of the compressor cavity and a low-pressure face on an opposite side thereof. The alternator has a rotor shaft operatively connected to the turbine and compressor, and is supported in the housing by bearings. Ridges extending from the low-pressure face of the compressor may be provided for balancing thrust across the compressor. Seals may be positioned about the alternator for selectively leaking fluid into the rotor cavity to reduce the temperature therein.

  17. VSD a compressor that automatically reduces the power consumption; VSD un compresor que reduce automaticamente el consumo energetico

    Energy Technology Data Exchange (ETDEWEB)

    De Anda L, Pedro [Atlas Copco, Mexico, D.F. (Mexico)


    With the purpose of verifying the behavior in the demand of air in the different plants Copco Atlas made a sampling of 135 measurements, from which it was concluded, that the air consumption of the plants behaves under three main profiles. In the following graphs the behavior of the demand of air with one color for every day of the week and 24 hours per day. In this sample Profile No. 1 is typical of the industries that work 24 hours a day and have low demand of air at night. This type of profile represents a percentage of 64% of the total of the measurements made. The second profile represents industries that work 5 days per week with two shifts and represents a percentage of 28%. The third profile is typical for applications of fixed consumption during the 5 days of the week, this represents an 8% of the measurements. With the purpose of improving the efficiency in the compressors energy consumption, Atlas Copco has been pioneering in the development of compressors with Variable Speed Drive (VSD), that offers the possibility of adapting with extreme precision the capacity of the compressor to the variable demand of compressed air of the plant. [Spanish] Con la finalidad de verificar el comportamiento en la demanda de aire en las diferentes plantas Atlas Copco realizo un muestreo de 135 mediciones, del cual se concluyo, que el consumo de aire de las plantas se comporta bajo tres perfiles principales. En las siguientes graficas se muestra el comportamiento de la demanda de aire con un color por cada dia de la semana y 24 horas al dia . En esta muestra el Perfil No. 1 es tipico de las Industrias que trabajan las 24 horas del dia y tiene baja demanda de aire en las noches. Este tipo de perfil representa un porcentaje de 64% del total de las mediciones realizadas. El segundo perfil representa industrias que traban 5 dias a la semana con dos turnos y representa un porcentaje de 28%. El tercer perfil estetico para aplicaciones de consumo fijo durante 5 dias a la semana

  18. An open reversed Brayton cycle with regeneration using moist air for deep freeze cooled by circulating water

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Shaobo [Guangdong Ocean University, College of Engineering, East Jiefang Rd. No. 40, Xiashan, Zhanjiang, Guangdong 524006 (China); Northwestern Polytechnical University, School of Aeroengine and Thermal Power Engineering, Xi' an, Shaanxi 710072 (China); Zhang, Hefei [Northwestern Polytechnical University, School of Aeroengine and Thermal Power Engineering, Xi' an, Shaanxi 710072 (China)


    This paper presents an open reversed Brayton cycle with regeneration using moist air for deep freeze cooled by circulating water, and proves its feasibility through performance simulation. Pinch technology is used to analyze the cooling of the wet air after compressor and the water used for cooling wet air after compressor. Its refrigeration depends mainly on the sensible heat of air and the latent heat of water vapor, its performance is more efficient than a conventional air-cycle, and the utilization of turbo-machinery makes it possible. The adoption of this cycle will make deep freeze easily and reduce initial cost because very low temperature, about -55 C, air is obtained. The sensitivity analysis of coefficient of performance to the efficiency of compressor and the efficiency of compressor, and the results of the cycle are also given. The simulation results show that the COP of this system depends on the temperature before turbine, the efficiency of compressor and the efficiency of compressor, and varies with the wet bulb temperature of the outdoor air. Humid air is a perfect working fluid for deep freeze with no cost to the user. (author)

  19. Measurement of Lubricating Condition between Swashplate and Shoe in Swashplate Compressors under Practical Operating Conditions (United States)

    Suzuki, Hisashi; Fukuta, Mitsuhiro; Yanagisawa, Tadashi

    In this paper, lubricating conditions between a swashplate and a shoe in a swashplate compressor for automotive air conditioners is investigated experimentally. The conditions are measured with an electric resistance method that utilizes the swash plate and the shoe as electrodes respectively. The instrumented compressor is connected to an experimental cycle with R134a and operated under various operating conditions of pressure and rotational speed. An improved measurement technique and applying a solid contact ratio to the measurement results permit to measure the lubricating condition at high rotational speed (more than 8000 rpm) and to predic an occurrence of scuffing between the swashplate and the shoe, and therefore enables a detailed study of lubricating characteristics. It is shown by the measurement that the voltage of the contact signal decreases, which means better lubricating condition, with the decrease of the compression pressure and with the increase of the rotational speed from 1000 rpm through 5000 rpm. The lubricating condition tends to worsen at more than 5000 rpm. Furthermore, it is confirmed that the lubricating condition under transient operation is worse obviously as compared with that under steady-state operation.

  20. Development of an Electrochemical Separator and Compressor

    Energy Technology Data Exchange (ETDEWEB)

    Trent Molter


    Global conversion to sustainable energy is likely to result in a hydrogen-based economy that supports U.S. energy security objectives while simultaneously avoiding harmful carbon emissions. A key hurdle to successful implementation of a hydrogen economy is the low-cost generation, storage, and distribution of hydrogen. One of the most difficult requirements of this transformation is achieving economical, high density hydrogen storage in passenger vehicles. Transportation applications may require compression and storage of high purity hydrogen up to 12,000 psi. Hydrogen production choices range from centralized low-pressure generation of relatively impure gas in large quantities from steam-methane reformer plants to distributed generation of hydrogen under moderate pressure using water electrolysis. The Electrochemical Hydrogen Separator + Compressor (EHS+C) technology separates hydrogen from impurities and then compresses it to high pressure without any moving parts. The Phase I effort resulted in the construction and demonstration of a laboratory-scale hardware that can separate and compress hydrogen from reformate streams. The completion of Phase I has demonstrated at the laboratory scale the efficient separation and compression of hydrogen in a cost effective manner. This was achieved by optimizing the design of the Electrochemical Hydrogen Compression (EHC) cell hardware and verified by parametric testing in single cell hardware. A broad range of commercial applications exist for reclamation of hydrogen. One use this technology would be in combination with commercial fuel cells resulting in a source of clean power, heat, and compressed hydrogen. Other applications include the reclamation of hydrogen from power plants and other industrial equipment where it is used for cooling, recovery of process hydrogen from heat treating processes, and semiconductor fabrication lines. Hydrogen can also be recovered from reformate streams and cryogenic boil-offs using this

  1. Improved operation of a microwave pulse compressor with a laser-triggered high-pressure gas plasma switch (United States)

    Shlapakovski, A.; Gorev, S.; Krasik, Ya. E.


    The influence of laser beam parameters on the output pulses of a resonant microwave compressor with a laser-triggered plasma switch was investigated. The S-band compressor, consisting of a rectangular waveguide-based cavity and H-plane waveguide tee with a shorted side arm, was filled with pressurized dry air and pumped by 1.8-μs-long microwave pulses of up to 450 kW power. A Nd:YAG laser was used to ignite the gas discharge in the tee side arm for output pulse extraction. The laser beam (at 213 nm or 532 nm) was directed along the RF electric field lines. It was found that the compressor operated most effectively when the laser beam was focused at the center of the switch waveguide cross-section. In this case, the power extraction efficiency reached ˜47% at an output power of ˜14 MW, while when the laser beam was not focused the maximal extraction efficiency was only ˜20% at ˜6 MW output power. Focusing the laser beam resulted also in a dramatic decrease (down to switch, and the jitter of the output pulses' appearance was minimized. In addition, the quality of the output pulses' waveform was significantly improved.

  2. Modeling and investigation of refrigeration system performance with two-phase fluid injection in a scroll compressor (United States)

    Gu, Rui

    Vapor compression cycles are widely used in heating, refrigerating and air-conditioning. A slight performance improvement in the components of a vapor compression cycle, such as the compressor, can play a significant role in saving energy use. However, the complexity and cost of these improvements can block their application in the market. Modifying the conventional cycle configuration can offer a less complex and less costly alternative approach. Economizing is a common modification for improving the performance of the refrigeration cycle, resulting in decreasing the work required to compress the gas per unit mass. Traditionally, economizing requires multi-stage compressors, the cost of which has restrained the scope for practical implementation. Compressors with injection ports, which can be used to inject economized refrigerant during the compression process, introduce new possibilities for economization with less cost. This work focuses on computationally investigating a refrigeration system performance with two-phase fluid injection, developing a better understanding of the impact of injected refrigerant quality on refrigeration system performance as well as evaluating the potential COP improvement that injection provides based on refrigeration system performance provided by Copeland.

  3. Prediction of gas pulsation of an industrial compressor

    Institute of Scientific and Technical Information of China (English)

    Heuicheol; Kim; Mi-Gyung; Cho; Jaehong; Park; Cheolho; Bai; Jaesool; Shim


    The measurement and prediction of gas pulsations are performed along the discharge pipeline of a reciprocating compressor for a refrigerator. A regression based experimental model of the one-dimensional acoustic field is developed. First, the conventional method for gas pulsation measurement and prediction, which separates the incident and reflected wave of acoustic waves traveling in the frequency domain, is discussed. Then, regression based on our proposed simple model, which is able to predict gas pulsation compared to the conventional method, is introduced for the analysis of a reciprocating compressor(The conventional method requires the value of sound speed in the piping line for the reciprocating compressor). A numerical prediction is made for the regression method. Three power spectrum values along the discharge pipeline are used for analysis, and two values are used for verification. Our results are in a good agreement with the conventional method.

  4. Performance Comparison of Capacity Control Methods for Reciprocating Compressors (United States)

    Wang, L.; Liu, G. B.; Zhao, Y. Y.; Li, L. L.


    Different capacity control methods are used for adjusting suction flow of reciprocating compressors to meet process need. Compared with recycle or bypass and suction throttling, three capacity control methods of speed control, clearance pockets and suction valve unloading are preferred due to their energy-saving at operating condition of partial load. The paper reviewed state of the art of the current capacity control technologies and their principles. A comprehensive mathematical model was developed to predict thermodynamic and dynamic performance of reciprocating compressors equipped with the capacity control systems of four above-mentioned methods. Comparison of shaft work and mechanical efficiency were conducted for different capacity control methods at the same condition. In addition, their influence on p-v diagram and valve motion were also studied, which is important for reliability and life of the reciprocating compressors. These results were helpful for selection of the capacity control systems by end-users and optimum design by manufacturers.

  5. Investigation of Surge Behavior in a Micro Centrifugal Compressor

    Institute of Scientific and Technical Information of China (English)

    Shimpei MIZUKI; Yuichiro ASAGA; Yushi ONO; Hoshio TSUJITA


    This paper reports the experimental and theoretical study of the surge occurred in prototyping an ultra micro centrifugal compressor. As the first step, the 10 times size model of an ultra micro centrifugal compressor having the 40 mm outer diameter was designed and manufactured. The detailed experimental investigations for the transient behavior of surge with several different values of B parameter were carried out. The experimental results during the surge were compared with those obtained by the non-linear lumped parameter theory in order to validate the effectiveness of the theoretical surge model for the micro centrifugal compressor. As a result, the quite different behavior of the surge appeared for the different values of B both in the experiment and in the analysis.

  6. Unsteady cooperative flow type in the axial compressor

    Institute of Scientific and Technical Information of China (English)

    ZHENG Xinqian; ZHOU Sheng; HOU Anping; XIONG Jinsong


    For increasing the performance of the axial compressor, a method for realizing unsteady cooperative flow type is proposed in this paper as a critical objective in the new generation of the axial compressor design system. Unsteady excitations were utilized to trigger the transformation from the unsteady natural flow pattern into the unsteady cooperative flow pattern, resulting in increment of aerodynamic performances of axial compressor. Numerical simulations show that distinct positive effect can be obtained for the 2D cascade in a wide range of subsonic working conditions. No positive effect can be observed under the 2D supersonic working conditions and unsteady excitations have little influence on the flow field space-time structure. However, positive effect can be obtained under the 3D transsonic working conditions. In addition, engineering applications of unsteady cooperative flow type are discussed.

  7. Fault detection in reciprocating compressor valves under varying load conditions (United States)

    Pichler, Kurt; Lughofer, Edwin; Pichler, Markus; Buchegger, Thomas; Klement, Erich Peter; Huschenbett, Matthias


    This paper presents a novel approach for detecting cracked or broken reciprocating compressor valves under varying load conditions. The main idea is that the time frequency representation of vibration measurement data will show typical patterns depending on the fault state. The problem is to detect these patterns reliably. For the detection task, we make a detour via the two dimensional autocorrelation. The autocorrelation emphasizes the patterns and reduces noise effects. This makes it easier to define appropriate features. After feature extraction, classification is done using logistic regression and support vector machines. The method's performance is validated by analyzing real world measurement data. The results will show a very high detection accuracy while keeping the false alarm rates at a very low level for different compressor loads, thus achieving a load-independent method. The proposed approach is, to our best knowledge, the first automated method for reciprocating compressor valve fault detection that can handle varying load conditions.

  8. A cryogenic axial-centrifugal compressor for superfluid helium refrigeration

    CERN Document Server

    Decker, L; Schustr, P; Vins, M; Brunovsky, I; Lebrun, P; Tavian, L


    CERN's new project, the Large Hadron Collider (LHC), will use superfluid helium as coolant for its high-field superconducting magnets and therefore require large capacity refrigeration at 1.8 K. This may only be achieved by subatmospheric compression of gaseous helium at cryogenic temperature. To stimulate development of this technology, CERN has procured from industry prototype Cold Compressor Units (CCU). This unit is based on a cryogenic axial-centrifugal compressor, running on ceramic ball bearings and driven by a variable-frequency electrical motor operating under low-pressure helium at ambient temperature. The machine has been commissioned and is now in operation. After describing basic constructional features of the compressor, we report on measured performance.

  9. A study on flow development in an APU-style inlet and its effect on centrifugal compressor performance (United States)

    Lou, Fangyuan

    The objectives of this research were to investigate the flow development inside an APU-style inlet and its effect on centrifugal compressor performance. The motivation arises from the increased applications of gas turbine engines installed with APU-style inlets such as unmanned aerial vehicles, auxiliary power units, and helicopters. The inlet swirl distortion created from these complicated inlet systems has become a major performance and operability concern. To improve the integration between the APU-style inlet and gas turbine engines, better understanding of the flow field in the APU-style inlet and its effect on gas turbine is necessary. A research facility for the purpose of performing an experimental investigation of the flow field inside an APU-style inlet was developed. A subcritical air ejector is used to continuously flow the inlet at desired corrected mass flow rates. The facility is capable of flowing the APU inlet over a wide range of corrected mass flow rate that matches the same Mach numbers as engine operating conditions. Additionally, improvement in the system operational steadiness was achieved by tuning the pressure controller using a PID control method and utilizing multi-layer screens downstream of the APU inlet. Less than 1% relative unsteadiness was achieved for full range operation. The flow field inside the rectangular-sectioned 90? bend of the APU-style inlet was measured using a 3-Component LDV system. The structures for both primary flow and the secondary flow inside the bend were resolved. Additionally, the effect of upstream geometry on the flow development in the downstream bend was also investigated. Furthermore, a Single Stage Centrifugal Compressor research facility was developed at Purdue University in collaboration with Honeywell to operate the APU-style inlet at engine conditions with a compressor. To operate the facility, extensive infrastructure for facility health monitoring and performance control (including lubrication


    The report presents results of a Phase I test of emissions packing technology offered by France Compressor Products which is designed to reduce methane leaks from compressor rod packing when a compressor is in a standby and pressurized state. This Phase I test was executed betwee...

  11. EFRC guidelines on how to avoid liquid problems in reciprocating compressor systems

    NARCIS (Netherlands)

    Shoeibi Omrani, P.; Eijk, A.


    Reciprocating compressors are widely used in a variety of industries. Issues with using reciprocating compressors are reliability concerns, especially system failures due to the presence of liquids. The working principle of reciprocating compressors are based on the gas compression of a closed volum

  12. Mountain Plains Learning Experience Guide: Heating, Refrigeration, & Air Conditioning. (United States)

    Carey, John

    This Heating, Refrigeration, and Air Conditioning course is comprised of eleven individualized units: (1) Refrigeration Tools, Materials, and Refrigerant; (2) Basic Heating and Air Conditioning; (3) Sealed System Repairs; (4) Basic Refrigeration Systems; (5) Compression Systems and Compressors; (6) Refrigeration Controls; (7) Electric Circuit…

  13. Numerical and experimental modelling of the radial compressor stage (United States)

    Syka, Tomáš; Matas, Richard; LuÅáček, Ondřej


    This article deals with the description of the numerical and experimental model of the new compressor stage designed for process centrifugal compressors. It's the first member of the new stages family developed to achieve the state of the art thermodynamic parameters. This stage (named RTK01) is designed for high flow coefficient with 3D shaped impeller blades. Some interesting findings were gained during its development. The article is focused mainly on some interesting aspects of the development methodology and numerical simulations improvement, not on the specific stage properties. Conditions and experimental equipment, measured results and their comparison with ANSYS CFX and NUMECA FINE/Turbo CFD simulations are described.

  14. Impact on the magnetic compressor due to CSR

    Institute of Scientific and Technical Information of China (English)

    LIU Chu-Yu; WANG Fang; WANG Er-Dong; QUAN Sheng-Wen; HAO Jian-Kui; LU Xiang-Yang; ZHANG Bao-Cheng; ZHAO Kui


    When an electron bunch is compressed in a chicane compressor,the CSR (coherent synchrotron radiation) will induce energy redistribution along the bunch.Such energy redistribution will affect the longitudinal emittance as a direct consequence.It will also excite betatron oscillation due to the chromatic transfer functions,and hence a transverse emittance change.So,it is indispensable for us to find a way to alleviate the CSR-cansed emittance dilution and the bad result of chicane compressor in PKU-FEL.

  15. Single-grating laser pulse stretcher and compressor. (United States)

    Lai, M; Lai, S T; Swinger, C


    Stretching and compressing of laser pulses is demonstrated with a single-grating apparatus. A laser pulse of 110 fs is stretched to 250 ps and then recompressed to 115 fs. The apparatus exploits a two-level structure: one level for stretching and the other for compressing. This single-grating configuration shows significant simplification in structure and alignment over existing multiple-grating systems. Such a stretcher-compressor is particularly suitable for use with chirped-pulse amplification in which laser wavelength tuning is desirable. Only one rotational adjustment is rquired to restore the alignment of the entire stretcher and compressor when the laser wavelength is changed.

  16. Performance of Oil-Injected Scroll Compressors for Helium Refrigerators (United States)

    Shiibayashi, Masao; Izunaga, Yasushi; Sado, Shintaro

    In recent years there arises growing demand of helium liquefaction refrigerators for the magnetic resonance imaging systems, magnetically levitated vehicles and other systems using superconducting magnet. From this background, a small size, scroll type of hermetic helium compressor capable of compressing helium gas to the pressure ratio of 20 in a single stage is developed. Main features of this compressor are as follows. 1) Discharge capacity can be varied from 7 to 20 Nm3/h by changing driving motor frequency from 30 to 80 Hz. 2) The overall adiabatic efficiency showed 72%∼79% under the pressure ratio range of 11∼20 at 60 Hz using oil injection cooling device.

  17. Cooling Performance Characteristics on Mobile Air-Conditioning System for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Ho-Seong Lee


    Full Text Available This study investigates the cooling performance characteristics of the mobile air-conditioning system using R744 (CO2 for the hybrid electric vehicle as an alternative to both the R-134a and the conventional air-conditioning system. The developed air-conditioning system is operated with an electric driven compressor in the battery driving mode and a belt driven compressor in the engine driving mode. The cooling performance characteristics of the developed system have been analyzed by experiments under various operating conditions of inlet air temperature, air flow rates for the gas cooler side and evaporator side, and electric compressor revolution respectively. As a result, cooling performances of the tested air-conditioning system for the EDC driving mode (electricity driven compressor were better than those for the BDC driving mode (belt driven compressor. The cooling capacity and cooling COP of the tested air-conditioning system for both driving modes were over 5.0 kW and 2.0, respectively. The observed cooling performance of the tested air-conditioning system may be sufficient for the cabin cooling of hybrid electric vehicles.

  18. Acceptance test report for 241-AW process air system

    Energy Technology Data Exchange (ETDEWEB)

    Kostelnik, A.J.


    The acceptance test procedure (ATP) for the compressed air system at building 241-AW-273 was completed on March 11, 1993. The system was upgraded to provide a reliable source of compressed air to the tank farm. The upgrade included the demolition of the existing air compressor and associated piping, as well as the installation of a new air compressor with a closed loop cooling system. A compressed air cross-tie was added to allow the process air compressor to function as a back-up to the existing instrument air compressor. The purpose of the ATP was to achieve three primary objectives: verify system upgrade in accordance with the design media; provide functional test of system components and controls; and prepare the system for the Operational Test. The ATP was successfully completed with thirteen exceptions, which were resolved prior to completing the acceptance test. The repaired exceptions had no impact to safety or the environment and are briefly summarized. Testing ensured that the system was installed per design, that its components function as required and that it is ready for operational testing and subsequent turnover to operations.

  19. Theoretical and experimental investigations on the match between pulse tube cold fingers and linear compressors (United States)

    Tan, Jun; Dang, Haizheng; Zhang, Lei


    The match between the cold finger and the linear compressor of the Stirling-type pulse tube cryocooler plays a vital role in optimizing the compressor efficiency and in improving the cold finger cooling performance. To reveal the match mechanism between the linear compressor and pulse tube cold finger (PTCF), detailed analyses have been made to understand the interactions between them. Based on the theoretical investigations, both of the design method of the PTCF to match the given linear compressor and a reverse method of the linear compressor to match the given PTCF have been proposed. In order to verify the validity of these theories and methods, actual PTCF and linear compressor are developed to match the existing linear compressor and PTCF, respectively. The experimental results show good agreements with the simulated ones.

  20. Technological advances of compressors in refrigerating machines. Evolutions technologiques des compresseurs de machines frigorifiques

    Energy Technology Data Exchange (ETDEWEB)

    Sartre, V.; Lallemand, M. (Centre National de la Recherche Scientifique, 69 - Villleurbanne (France)); Chiaffi, M. (Societe Bertin et Compagnie, 78 - Plaisir (France))


    The present study is related to the development of compressors for heat pumps and refrigerating machines. For a given application, various compressor technologies are possible. The choice is often dictated by the experience acquired on a compressor type, ensuring good reliability and a reasonable cost of the plant. In our study, we examine the limits of various compressor types: piston, screw, scroll, rotary vane, rolling piston and centrifugal. A comparison of the theoretical and practical limits of the compressors' operating ranges shows the necessity of better adaptation of the compressor type to each application. Finally, we suggest the main research focus for the development of future compressors. The new technologies should evolve towards a variable-speed operation, without lubricating oil or with refrigerant lubrication. Acoustic comfort is also an important criterion. (author)

  1. Diagnostic Tools for the Monitoring and Organization of In-Situ Air Sparging Systems (United States)


    Andrea Leeson, Rob Hinchee, Dave McWhorter, and Mike Marley for In Situ Air Sparging (IAS) project peer review. I would like to thank my fellow grad...the tank at the air inlet valve for sparging experiments. The compressor is a DeVilbiss Model F5020 with a 20 gallon air tank. An onboard pressure

  2. Variable speed hermetic reciprocating compressors for domestic refrigerators

    DEFF Research Database (Denmark)

    Rasmussen, Bjarne D.


    This article describes the results of a both theoretical and experimental investigation of the performance of variable speed hermetic reciprocating compressors for domestic refrigerators. The investigation was performed as a part of a larger research project with the objective of reducing...

  3. A Device for Measuring Sonic Velocity and Compressor Mach Number (United States)


    resonator (the only 4 NACA TN No. 1664 accurate measurement required) is measured, as shomn in figure 1, by means of a mercury manometer . The compressor vs not connected to the ccmpressor inlet until after calibration. The pressure in the device was measured by means of the mercury manometer . Fram

  4. Development of the Larzac Engine Rig for Compressor Stall Testing (United States)


    prediction, and experiments to detect and identify stall and surge precursors in the operation of multi stage compressors in aero engines. He received...similarly to an iris or a camera shutter and achieved its throttling by the gradual reduction of the effective area of the by-pass exit annulus

  5. Optimisation of acoustic silencer for the screw compressor system

    NARCIS (Netherlands)

    Swamy, M.; Lier, L.J. van; Smeulers, J.P.M.


    In one of the screw compressor system, designed silencer was not optimal. A great challenge was the large variation in operating conditions, especially the variation of the molecular weight of the gas. There was need to optimize the silencer. This paper describes the acoustic modelling tools to opti

  6. An experimental method for validating compressor valve vibration theory

    NARCIS (Netherlands)

    Habing, R.A.; Peters, M.C.A.M.


    This paper presents an experimental method for validating traditional compressor valve theory for unsteady flow conditions. Traditional valve theory considers the flow force acting on the plate and the flow rate as quasi-steady variables. These variables are related via semi-empirical coefficients w

  7. Development of Compressor for Ultra Micro Gas Turbine

    Institute of Scientific and Technical Information of China (English)

    Shimpei MIZUKI


    The major problems for the development of an ultra micro gas turbine system were discussed briefly from the stand point of the internal flow and the performance characteristics. Following to these, the development of ultra micro centrifugal compression systems for the ultra micro gas turbine is explained with the design and the manufacturing processes. The measured results of ultra micro centrifugal compressors are shown.

  8. Increased turbo compressor reliability by analysis of fluid structure interaction

    NARCIS (Netherlands)

    Smeulers, J.P.M.; González Díez, N.


    The integrity of compressors and pumps is of paramount importance for the gas and oil industry. Failures may result in serious production losses that are in no proportion with the cost of the equipment involved. Besides, the equipment may be inaccessible for maintenance for a long period of time due

  9. Motor-driven compressor-condenser group for cooling cycles

    Energy Technology Data Exchange (ETDEWEB)

    Giuffrida, G.G.


    A motor-driven compressor condenser group for equipment actuating cooling-cycles, such as for example cooling apparatuses and heat pumps, enclosed in a single container. The cooling fluid of the heat-exchanger connected to the condenser passing to and from the container is to be used in domestic cooling systems to heat water.

  10. Numerical Study of Unsteady Flow in Centrifugal Cold Compressor (United States)

    Zhang, Ning; Zhang, Peng; Wu, Jihao; Li, Qing

    In helium refrigeration system, high-speed centrifugal cold compressor is utilized to pumped gaseous helium from saturated liquid helium tank at low temperature and low pressure for producing superfluid helium or sub-cooled helium. Stall and surge are common unsteady flow phenomena in centrifugal cold compressors which severely limit operation range and impact efficiency reliability. In order to obtain the installed range of cold compressor, unsteady flow in the case of low mass flow or high pressure ratio is investigated by the CFD. From the results of the numerical analysis, it can be deduced that the pressure ratio increases with the decrease in reduced mass flow. With the decrease of the reduced mass flow, backflow and vortex are intensified near the shroud of impeller. The unsteady flow will not only increase the flow loss, but also damage the compressor. It provided a numerical foundation of analyzing the effect of unsteady flow field and reducing the flow loss, and it is helpful for the further study and able to instruct the designing.

  11. Data compressor designed to improve recognition of magnetic phases (United States)

    Vogel, E. E.; Saravia, G.; Cortez, L. V.


    Data compressors available in the web have been used to determine magnetic phases for two-dimensional (2D) systems [E. Vogel, G. Saravia, F. Bachmann, B. Fierro, J. Fischer, Phase transitions in Edwards-Anderson model by means of information theory, Physica A 388 2009 4075-4082]. In the present work, we push this line forward along four different directions. First, the compressor itself: we design a new data compressor, named wlzip, optimized for the recognition of information having physical (or scientific) information instead of the random digital information usually compressed. Second, for the first time we extend the data compression analysis to the 3D Ising ferromagnetic model using wlzip. Third, we discuss the tuning possibilities of wlzip in terms of the number of digits considered in the compression to yield maximum definition; in this way, the transition temperature of both 2D and 3D Ising ferromagnets can be reported with very good resolution. Fourth, the extension of the time window through which the data file is actually compressed is also considered to get optimum accuracy. The paper is focused on the new compressor, its algorithm in general and the way to apply it. Advantages and disadvantages of wlzip are discussed. Toward the end, we mention other possible applications of this technique to recognize stable and unstable regimes in the evolution of variables in meteorology (such as pollution content or atmospheric pressure), biology (blood pressure) and econophysics (prices of the stock market).

  12. Numerical Simulation of Flow Instabilities in High Speed Multistage Compressors

    Institute of Scientific and Technical Information of China (English)

    JunHu; ThomasPeters; 等


    In the present paper,a nonlinear multi“actuator disk” model is proposed to analyze the dynamic behavior of flow instabilities,including rotating stall and surge,in high speed multistage axial compressors.The model describes the duct flow fields using two dimensional,compressible and unsteady Euler equations,and accounts for the influences of downstream plenum and throttle in the system as well.It replaces each blade row of multistage compressore with a disk.For numerical calculations,the time marching procedure,using MacCormack two steps scheme,is used.The main pupose of this paper is to predict the mechanism of two dimensional short wavelength rotating stall inception and the interation between blade rows in high speed multistage compressors.It has been demonstrated that the model has the ability to predict those phenomena,and the results show that some system parameters have a strong effect on the stall features as well.Results for a five stage high speed compressor are analyzed in detail,and comparison with the experimental data demonstrates that the model and calculating results are reliable.


    Energy Technology Data Exchange (ETDEWEB)

    Michael J. Crowley; Prem N. Bansal; John E. Tessaro


    Dresser-Rand completed the preliminary aerodynamic flowpath of the volute and inlet design for the compressor section. This has resulted in considerable progress being made on the development of the compressor section and ultimately towards the successful integration of the IEMDC System design. Significant effort was put forth in the design of aerodynamic components which resulted in a design that meets the limits of aerodynamically induced radial forces previously established. Substantial effort has begun on the mechanical design of the compressor pressure containing case and other internal components. These efforts show progression towards the successful integration of a centrifugal compressor and variable speed electric motor ventilated by the process gas. All efforts continue to confirm the feasibility of the IEMDC system design. During the third quarter reporting period, the focus was to further refine the motor design and to ensure that the IEMDC rotor system supported on magnetic bearing is in compliance with the critical speed and vibration requirements of the API standards 617 and 541. Consequently specification to design magnetic bearings was developed and an RFQ to three magnetic bearing suppliers was issued. Considerable work was also performed to complete preliminary reports on some of the deliverable tasks under phase 1.0. These include specification for the VFD, RFQ for the magnetic bearings, and preliminary write-up for motor instrumentation and control schematic. In order to estimate motor efficiency at various operating points, plots of calculated motor losses, and motor cooling gas flow rates were also prepared. Preliminary evaluations of motor support concepts were performed via FEA to determine modal frequencies. Presentation was made at DOE Morgantown on August 12, 2003 to provide project status update. Preparations for the IEMDC motor-compressor presentation, at the GMRC conference in Salt Lake City to be held on October 5, 2003, were also

  14. Compressed Air System Optimization: Case Study Food Industry in Indonesia (United States)

    Widayati, Endang; Nuzahar, Hasril


    Compressors and compressed air systems was one of the most important utilities in industries or factories. Approximately 10% of the cost of electricity in the industry was used to produce compressed air. Therefore the potential for energy savings in the compressors and compressed air systems had a big challenge. This field was conducted especially in Indonesia food industry or factory. Compressed air system optimization was a technique approach to determine the optimal conditions for the operation of compressors and compressed air systems that included evaluation of the energy needs, supply adjustment, eliminating or reconfiguring the use and operation of inefficient, changing and complementing some equipment and improving operating efficiencies. This technique gave the significant impact for energy saving and costs. The potential savings based on this study through measurement and optimization e.g. system that lowers the pressure of 7.5 barg to 6.8 barg would reduce energy consumption and running costs approximately 4.2%, switch off the compressor GA110 and GA75 was obtained annual savings of USD 52,947 ≈ 455 714 kWh, running GA75 light load or unloaded then obtained annual savings of USD 31,841≈ 270,685 kWh, install new compressor 2x132 kW and 1x 132 kW VSD obtained annual savings of USD 108,325≈ 928,500 kWh. Furthermore it was needed to conduct study of technical aspect of energy saving potential (Investment Grade Audit) and performed Cost Benefit Analysis. This study was one of best practice solutions how to save energy and improve energy performance in compressors and compressed air system.

  15. Adiabatic Liquid Piston Compressed Air Energy Storage


    Petersen, Tage; Elmegaard, Brian; Pedersen, Allan Schrøder


    This project investigates the potential of a Compressed Air Energy Storage system (CAES system). CAES systems are used to store mechanical energy in the form of compressed air. The systems use electricity to drive the compressor at times of low electricity demand with the purpose of converting the mechanical energy into electricity at times of high electricity demand. Two such systems are currently in operation; one in Germany (Huntorf) and one in the USA (Macintosh, Alabama). In both cases, ...

  16. Aircraft Performance Enhancement with Active Compressor Stabilization (United States)


    Company in 1985 to provide an in- house propulsion assessment capability to the Air Force’s Aero Propulsion Laboratory. PWSIM consists of approximately...Markl2 Format) 107 ALTF PMa Atbume (IN CA.F. CorreeW Ailow (Wou) M LIft Coff awt o Distance inrn) FNAV Net Thr’,rt Avagable (Ob) LID Lift to Drag Ratpo w

  17. Numerical study of a high-speed miniature centrifugal compressor (United States)

    Li, Xiaoyi

    A miniature centrifugal compressor is a key component of reverse Brayton cycle cryogenic cooling system. The system is commonly used to generate a low cryogenic temperature environment for electronics to increase their efficiency, or generate, store and transport cryogenic liquids, such as liquid hydrogen and oxygen, where space limit is also an issue. Because of space limitation, the compressor is composed of a radial IGV, a radial impeller and an axial-direction diffuser (which reduces the radial size because of smaller diameter). As a result of reduction in size, rotating speed of the impeller is as high as 313,000 rpm, and Helium is used as the working fluid, in order to obtain the required static pressure ratio/rise. Two main characteristics of the compressor---miniature and high-speed, make it distinct from conventional compressors. Higher compressor efficiency is required to obtain a higher COP (coefficient of performance) system. Even though miniature centrifugal compressors start to draw researchers' attention in recent years, understanding of the performance and loss mechanism is still lacking. Since current experimental techniques are not advanced enough to capture details of flow at miniature scale, numerical methods dominate miniature turbomachinery study. This work numerically studied a high speed miniature centrifugal compressor with commercial CFD code. The overall performance of the compressor was predicted with consideration of interaction between blade rows by using sliding mesh model. The law of similarity of turbomachinery was validated for small scale machines. It was found that the specific ratio effect needs to be considered when similarity law is applied. But Reynolds number effect can be neglected. The loss mechanism of each component was analyzed. Loss due to turning bend was significant in each component. Tip leakage loss of small scale turbomachines has more impact on the impeller performance than that of large scale ones. Because the

  18. Development of a High Efficiency Compressor/Expander for an Air Cycle Air Conditioning System. (United States)


    house using a mercury monometer as the testing standard. The monometer used was a Meriam instrument model 310ECOWM. Corrections were made to the...monometer reading for altitude and ambient temperature affects. The temperature correction was obtained from the Meriam Instrument Company. The torque

  19. Air management system for automotive fuel cells; Luftversorgungssystem fuer Fahrzeugbrennstoffzellen

    Energy Technology Data Exchange (ETDEWEB)

    Kauder, K.; Temming, J. [Dortmund Univ. (Germany). Fachgebiet Fluidenergiemaschinen


    Fuel cells have attained a predominant position in the development of alternative automotive drives during the last few years. The Polymer Electrolyte Membrane Fuel Cell (PEMFC), preferred for automotive applications, requires compressed air for maximum efficiency. In most prototypes this is provided by twin-screw compressors. The article introduces the different types of fuel cells, and the system and requirements of mobile applications of fuel cells. The advantages and development potential of screw compressors are described. Furthermore concepts of a compressor-expander module based on screw machines are presented and discussed. (orig.) [German] Bei der Entwicklung alternativer Fahrzeugantriebe hat die Brennstoffzelle in den letzten Jahren eine vorherrschende Stellung eingenommen. Die Polymer-Elektrolyt-Membran Brennstoffzelle, PEMFC, die fuer automotive Anwendungen bevorzugt verwendet wird, benoetigt fuer einen optimalen Wirkungsgrad eine Druckluftversorgung. Als Compressor kommt derzeit insbesondere der Schraubenlader bzw. -compressor in verschiedenen Prototypenfahrzeugen zum Einsatz. Der Beitrag behandelt zunaechst die unterschiedlichen Brennstoffzellentypen, den Systemaufbau und die Anforderungen an die mobile Anwendung der Brennstoffzelle. Fuer diesen speziellen Anwendungsfall werden Vorteile und Entwicklungsmoeglichkeiten der Schraubenmaschine dargelegt. Davon ausgehend finden sich Konzepte zum Aufbau eines Compressor-Expander-Moduls (CEM) auf Basis der Schraubenmaschinen. (orig.)


    Energy Technology Data Exchange (ETDEWEB)

    Michael J. Crowley; Prem N. Bansal


    This report contains the final project summary and deliverables required by the award for the development of an In-line Electric Motor Driven Compressor (IEMDC). Extensive work was undertaken during the course of the project to develop the motor and the compressor section of the IEMDC unit. Multiple design iterations were performed to design an electric motor for operation in a natural gas environment and to successfully integrate the motor with a compressor. During the project execution, many challenges were successfully overcome in order to achieve the project goals and to maintain the system design integrity. Some of the challenges included limiting the magnitude of the compressor aerodynamic loading for appropriate sizing of the magnetic bearings, achieving a compact motor rotor size to meet the rotor dynamic requirements of API standards, devising a motor cooling scheme using high pressure natural gas, minimizing the impact of cooling on system efficiency, and balancing the system thrust loads for the magnetic thrust bearing. Design methods that were used on the project included validated state-of-the-art techniques such as finite element analysis and computational fluid dynamics along with the combined expertise of both Curtiss-Wright Electro-Mechanical Corporation and Dresser-Rand Company. One of the most significant areas of work undertaken on the project was the development of the unit configuration for the system. Determining the configuration of the unit was a significant step in achieving integration of the electric motor into a totally enclosed compression system. Product review of the IEMDC unit configuration was performed during the course of the development process; this led to an alternate design configuration. The alternate configuration is a modular design with the electric motor and compressor section each being primarily contained in its own pressure containing case. This new concept resolved the previous conflict between the aerodynamic flow

  1. Comparative assessment of characteristic part-load performances of screw compressors and turbo-compressors; Vergleich der charakteristischen Teillastwirkungsgrade von Schrauben- und Turboverdichtern

    Energy Technology Data Exchange (ETDEWEB)

    Brasz, J.J.; Hartmann, K. [Carrier Corp., Syracuse, NY (United States)]|[Carrier Corp., Muenchen (Germany)


    The relative part-load performance of screw compressors and radial compressors is compared. Compressor part load is represented by a 2D characteristic field with the pressure on the vertical axis as a function of mass flow on the horizontal axis, with efficiencies given for any possible combination of pressure and mass flow. While this manner of representation is common for radial compressors, it is new for screw compressors. In the comparison of compression efficiencies, the focus is on vapour compression. For a valid comparative assessment of total compression, also the mechanical and/or electric loss through bearings, transmission, drive and (in case of variable-speed drives) frequency converters must be taken into account. (orig.)

  2. The Role of Tip Leakage Flow in Triggering Rotating Stall of a Low Speed Compressor under Inlet Distortion

    Institute of Scientific and Technical Information of China (English)

    Jingxuan Zhang; Feng Lin; Jingyi Chen; Chaoqun Nie


    The stall behavior in a single-stage low-speed axial compressor under rotating inlet distortion (RID) is investi-gated in the first half of this paper. The tests demonstrate that the tip leakage flow (TLF) plays an important rolein triggering rotating stall. The tracking of the spike-like disturbances caused by the spillage of TLV indicates that most of such spike-like disturbances will be smeared by non-distorted sector and the growth of the spike-like dis-turbances actually relate closely to how and how often the path of the propagating disturbances come across the path of the rotating distorted sector. In the second half of this paper, micro air injections are applied to test the ef-fect behavior of TLF on stall inception. Contrasts to without micro air injections, the spike-like disturbances are much fewer, so the possibilities that spike-like disturbances may trigger rotating stall are fewer too. As a result, the compressor gets a lower mass flow rate at stall for both co-rotating inlet distortion and counter-rotating inlet distortion.

  3. Development of nanolubricant automotive air conditioning (AAC test rig

    Directory of Open Access Journals (Sweden)

    Redhwan A.A.M.


    Full Text Available Nanolubricant been introduced in compressor might improve the performance of automotive air conditioning system. Prior testing of the nanolubricant enhancement performance, an automotive air conditioning (AAC system test rig base on compact car has to be developed; therefore this paper presented the development process of AAC test rig. There are 15 thermocouples, 2 pressure gauges and power analyzer were assembled on the system in order to analyse its performance. The experiment was conducted with four different charged of refrigerant. The charging was based on initial weight charged. At each quantity of refrigerant charge, performance of the AAC system was evaluated by determining three important parameters which is cooling capacity, compressor work and coefficient of performance (COP. The maximum average COP is achieved at 900 RPM is 7.07. The average and maximum COP enhancement of 7.07 % and 13.34 % were achieved by applying SiO2 nanolubricant inside the compressor.

  4. Performance studies on an axial flow compressor stage (United States)

    Sitaram, N.


    A low-speed, medium loaded axial flow compressor stage is studied experimentally and theoretically. The flow compressor facility, composed of an inlet guide vane row, a rotor blade row, and a stator blade row, and the principles of the streamline curvature method (SCM) and the Douglas-Neumann cascade program are described. The radial distribution of the flow properties, the rotor blade static pressure distribution, and the lift coefficient and relative flow angle derived experimentally and theoretically are compared. It is determined that there is good correlation between the experimental flow properties and the SCM data, the Douglas-Neumann cascade program and experimental rotor blade static pressure data, and the experimental and theoretical lift coefficients only in the midspan region. Modifications to the SCM and the Douglas-Neumann cascade program in order to improve their accuracy are discussed.

  5. Global Dynamics of a Compressor Blade with Resonances

    Directory of Open Access Journals (Sweden)

    Xiaoxia Bian


    Full Text Available The global bifurcations and chaotic dynamics of a thin-walled compressor blade for the resonant case of 2 : 1 internal resonance and primary resonance are investigated. With the aid of the normal theory, the desired form associated with a double zero and a pair of pure imaginary eigenvalues for the global perturbation method is obtained. Based on the simpler form, the method developed by Kovacic and Wiggins is used to find the existence of a Shilnikov-type homoclinic orbit. The results obtained here indicate that the orbit homoclinic to certain invariant sets for the resonance case which may lead to chaos in the sense of Smale horseshoes for the system. The chaotic motions of the rotating compressor blade are also found by using numerical simulation.

  6. Dynamical System Analysis of Unsteady Phenomena in Centrifugal Compressor

    Institute of Scientific and Technical Information of China (English)

    YasuyukiKomatsubara; ShimpeiMizuki


    Surge and rotating stall occurring in a centrifugal compressor system are investigated by using a phase portrait reconstruction method.From experimentally measured time series of data,the method clarified the cyclic behavior of surge.For rotating stall,there still remain problems in the phase portrait due to the chaotic behavior.However,the results obtained by the present method are able to provide new insights to the modelings for surge and rotating stall.Surge and roatting stall occurring in a centrifugal compressor system are investigated by using a phase portrait reconstruction method.From experimentally measured time series of data,the method clarified the cylcic behavior of surge.For rotating stall,there still remain problems in the phase portrait due to the chaotic behavior.However,the results obtained by the present method are able to provide new insights to the modelings for surge and rotating stall.

  7. Heat powered refrigeration compressor. Semi-annual technical report

    Energy Technology Data Exchange (ETDEWEB)

    Goad, R.R.


    The objective of this program is to develop and improve the design of previously started prototypes of the Heat Powered Refrigeration Compressor. To build this prototype and ready it for testing by the University of Evansville is another goal. This prototype will be of similar capacity as the compressor that will eventually be commercially produced. This unit can operate on almost any moderate temperature water heat source. This heat source could include such applications as industrial waste heat, solar, wood burning stove, resistance electrical heat produced by a windmill, or even perhaps heat put out by the condenser of another refrigeration system. Work performed in the past four months has consisted of: engineering of HX-1; comparisons of specifications from different companies to ensure state of the art applications of parts for project; coordinating project requirements with machine shop; designing condenser; and partial assembly of HX-1.

  8. Quasi-Optical 34-GHz Rf Pulse Compressor

    Energy Technology Data Exchange (ETDEWEB)

    Hirshfield, Jay L


    Designs have been carried out on non-high-vacuum, low-power versions of three- and four-mirror quasi-optical passive and active Ka-band pulse compressors, and prototypes built and tested based on these designs. The active element is a quasi-optical grating employing gas discharge tubes in the gratings. Power gains of about 3:1 were observed experimentally for the passive designs, and about 7:1 with the active designs. High-power, high-vacuum versions of the three-and four-mirror quasi-optical pulse compressors were built and tested at low power. These now await installation and testing using multi-MW power from the 34-GHz magnicon.

  9. Experimental study on neon refrigeration system using commercial helium compressor (United States)

    Ko, Junseok; Kim, Hyobong; Hong, Yong-Ju; Yeom, Hankil; Koh, Deuk-Yong; Park, Seong-Je


    In this study, we developed neon refrigeration system using commercial helium compressor which was originally designed for GM cryocooler. We performed this research as precedent study before developing neon refrigeration system for small-scale hydrogen liquefaction system. The developed system is based on precooled Linde-Hampson system with liquid nitrogen as precoolant. Design parameters of heat exchangers are determined from thermodynamic cycle analysis with operating pressure of 2 MPa and 0.4 MPa. Heat exchangers have concentric-tube heat exchanger configuration and orifice is used as Joule- Thomson expansion device. In experiments, pressure, temperature, mass flow rate and compressor input power are measured as charging pressure. With experimental results, the characteristics of heat exchanger, Joule-Thomson expansion and refrigeration effect are discussed. The developed neon refrigeration system shows the lowest temperature of 43.9 K.

  10. Small, high pressure ratio compressor: Aerodynamic and mechanical design (United States)

    Bryce, C. A.; Erwin, J. R.; Perrone, G. L.; Nelson, E. L.; Tu, R. K.; Bosco, A.


    The Small, High-Pressure-Ratio Compressor Program was directed toward the analysis, design, and fabrication of a centrifugal compressor providing a 6:1 pressure ratio and an airflow rate of 2.0 pounds per second. The program consists of preliminary design, detailed areodynamic design, mechanical design, and mechanical acceptance tests. The preliminary design evaluate radial- and backward-curved blades, tandem bladed impellers, impeller-and diffuser-passage boundary-layer control, and vane, pipe, and multiple-stage diffusers. Based on this evaluation, a configuration was selected for detailed aerodynamic and mechanical design. Mechanical acceptance test was performed to demonstrate that mechanical design objectives of the research package were met.

  11. Linear Gain for the Microbunching Instability in an RF Compressor

    Energy Technology Data Exchange (ETDEWEB)

    Venturini, M.; Migliorati, M.; Ronsivalle, C.; Vaccarezza, C.


    Velocity (or rf) compression has been suggested as a technique for bunch compression complementary to the more established technique involving magnetic chicanes and represents an important research item being investigated at the SPARC test facility. One of the aspects of this technique still not sufficiently understood is its possible impact on the microbunching instability. The purpose of this report is to present the analytical framework for investigating this instability in rf compressors. We use methods similar to those successfully applied to magnetic compressors and derive some integral equations yielding the gain for the instability in linear approximation. The focus here is on the derivation of the relevant equations. Although examples of solutions to these equations are provided we defer a more comprehensive discussion of their implication to a future report. The present study is part of a larger effort for a more comprehensive investigation that eventually will include macroparticle simulations and experiments.

  12. Performance Improvement of a Centrifugal Compressor by Passive Means

    Directory of Open Access Journals (Sweden)

    N. Sitaram


    Full Text Available The present experimental investigation deals with performance improvement of a low-speed centrifugal compressor by inexpensive passive means such as turbulence generator placed at different positions and partial shroud near the rotor blade tip. The experiments are carried out at three values of tip clearance, namely 2.2%, 5.1%, and 7.9% of rotor blade height at the exit. Performance tests are carried out for a total of 13 configurations. From these measurements, partial shroud is found to give the best performance. The improvement in the compressor performance may be due to the reduction of tip leakage flows by the small extension of partial shroud (2 mm on the pressure surface side. Although there is nominal change in performance due to turbulence generator (TG, TG has beneficial effect of increased operating range.


    Energy Technology Data Exchange (ETDEWEB)

    Michael J. Crowley; Prem N. Bansal; John E. Tessaro


    During this reporting period, significant progress has been made towards the development of the IEMDC System design. Considerable effort was put forth by Curtiss-Wright EMD in the resolution of the technical issue of aerodynamically induced radial forces. This has provided a design basis with which to establish the radial magnetic bearing load capacity and the rotordynamic design. Dresser-Rand has made considerable progress on the flowpath design for the compressor section particularly on the volute and inlet aerodynamic design. All efforts show progression towards the successful integration of a centrifugal compressor and variable speed electric motor ventilated by the process gas. These efforts continue to confirm the feasibility of the IEMDC system design.

  14. Trends in high performance compressors for petrochemical and natural gas industry in China (United States)

    Zhao, Yuanyang; Li, Liansheng


    Compressors are the key equipment in the petrochemical and natural gas industry system. The performance and reliability of them are very important for the process system. The application status of petrochemical & natural gas compressors in China is presented in this paper. The present status of design and operating technologies of compressors in China are mentioned in this paper. The turbo, reciprocating and twin screw compressors are discussed. The market demands for different structure compressors in process gas industries are analysed. This paper also introduces the research and developments for high performance compressors in China. The recent research results on efficiency improvement methods, stability improvement, online monitor and fault diagnosis will also be presented in details.

  15. Investigation into the Interaction of Centrifugal Compressor Impeller and Vaneless Diffuser

    Institute of Scientific and Technical Information of China (English)

    YANG Ce; ZHANG Dian-zuo; MA Chao-chen; HU Liao-ping


    Centrifugal compressors with parallel-wall and contracting wall vaneless diffuser are designed by using centrifugal compressor computer-aided integrated design system. The internal flow fields of the compressor are calculated by solving three-dimensional Navier-Stokes equation. Four aspects are investigated and calculation results show that the total efficiencies and total pressure ratios of the compressor with contracting wall vaneless diffuser is higher than that of the compressor with parallel-wall. The jet and wake don't mix rapidly inside vaneless diffuser. The outlet blade lean angle doesn't affect the compressor performance. The greater the mass flow rate through impeller, the more uneven the velocity distribution at impeller outlet is.

  16. The Force Analysis of Reciprocating Compressor Valve Using CFD%往复式压缩机气阀受力的CFD分析

    Institute of Scientific and Technical Information of China (English)

    武炳; 江志农


    针对采用顶开进气阀式进行全量程无级气量调节的往复式压缩机工作过程进行CFD模拟,得出往复式压缩机工作过程中气缸和气阀部分的气体压力场分布,计算出了阀片所受的最大气体顶推力,为气量调节系统的设计提供了依据.%A working process of reciprocating compressor, which uses pressing-off inlet valve for whole measuring range stepless gas-regulating, is simulated using CFD. The air pressure filed distribution in cylinder and valve during the working process of reciprocating compressor is obtained, and the largest gas jacking force on valve is calculated. The results provide basis for the design of gas capacity regulation system.

  17. Dedicated monitoring and machinery protection systems on reciprocating compressors

    Energy Technology Data Exchange (ETDEWEB)

    Grande, Alvaro; Wenisch, Markus [Hoerbiger Ventilwerke GmbH and Co KG, Wien (Austria); Jacobs, Denis [HOERBIGER do Brasil Industria de Equipamentos, Cajamar, SP (Brazil)


    Growing demands on reciprocating compressors (recips) in the process gas industry require particular solutions for machinery protection and performance monitoring systems. Compared to rotating equipment, monitoring systems for recips have to consider the special mechanical and physical characteristics, such as oscillating masses, variable vibration behaviour and varying operating conditions. Furthermore, they provide valuable information about the performance of cylinder related components allowing the operator the optimization of efficiency and availability, and therefore increase production. (author)

  18. Computational and Experimental Study of an Industrial Centrifugal Compressor Volute

    Institute of Scientific and Technical Information of China (English)

    HarriPitkanen; HannuEsa; 等


    A centrifugal compressor with a vaneless diffuser was studied experimentally and numericallly.The main target of the study was to analyze the volute flow.Two different volute geometries was studied.The numerical solution was done by using a steady-state RANS code at both design and off-design conditions.Both calculated and measured pressure and velocity distributions are presented.

  19. Recontouring of Jet Engine Compressor Blades by Flow Simulation


    Herwart Hönen; Matthias Panten


    In modern jet propulsion systems the core engine has an essential influence on the total engine performance. Especially the high pressure compressor plays an important role in this scheme. Substantial factors here are losses due to tip clearance effects and aerodynamic airfoil quality. During flight operation the airfoils are subject to wear and tear on the leading edge. These effects cause a shortening of the chord length and the leading edge profiles become deformed. This results in a deter...

  20. Stall inception in a high-speed axial compressor (United States)

    Cameron, Joshua David

    A research program designed to provide understanding of the fluid dynamic mechanisms that lead to rotating stall in the Notre Dame Stage 01 high-speed axial compressor is described. The stalling behavior of this compressor was studied with unsteady casing pressure measurements from a circumferentially spaced array of sensors. In addition, over rotor casing surface streak measurements were performed to investigate the time-averaged end-wall flow near the rotor at operating points near stall. Several investigative tools were applied to the analysis and interpretation of the unsteady casing pressure data. Traditional methods such as visual inspection, spatial Fourier decomposition, traveling wave energy and wavelet analysis were shown to be insufficient to characterize the pre-stall and stall inception behavior of the compressor. A new technique based on a windowed two-point correlation between adjacent sensors was developed and demonstrated to provide spatial and temporal resolution of both pre-stall and stall inception behavior. The spatial correlation technique was then applied to the analysis of stall inception data from experiments with asymmetric tip clearance. The non-uniform tip clearance was produced using the magnetic bearings which levitate the rotor shaft of the Notre Dame Transonic Axial Compressor facility. Both steady rotor centerline offset and rotor whirl were investigated. The results of these experiments, along with the surface streak measurements, provide evidence in support of recent computational observations (found in the literature) that predict that short length scale stall inception is related to specific features of the rotor tip clearance flow.

  1. Design and Characterization of a Centrifugal Compressor Surge Test Rig



    A detailed description of a new centrifugal compressor surge test rig is presented. The objective of the design and development of the rig is to study the surge phenomenon in centrifugal compression systems and to investigate a novel method of surge control by active magnetic bearing servo actuation of the impeller axial tip clearance. In this paper, we focus on the design, initial setup, and testing of the rig. The latter two include the commissioning of the rig and the experimental characte...

  2. Dynamic Analysis of Integrally Geared Compressors with Varying Workloads

    Directory of Open Access Journals (Sweden)

    Ming Zhang


    Full Text Available Integrally geared compressors are characterized by compact and high efficiency machines, which are widely used in modern processing industries. As an important part of integrally geared compressors, a geared rotor-bearing system exhibits complicated dynamic behaviors. When running at rated speeds, a coupling system likely produces resonance with an adjusted workload, and a critical load phenomenon occurs. The dynamic coefficients of bearings, axial force and torque, and gear meshing stiffness vary with workload because of the interaction between rotors. In this study, a dynamic model of a geared rotor-bearing system influenced by the dynamic coefficients of bearings, axial force and torque, and gear meshing stiffness is developed. The dynamic responses of the coupling system are calculated and analyzed by using a typical five-shaft integrally geared compressor as an example. The effects of different parameters on the dynamic behaviors of the proposed system are also considered in the discussion. The geared rotor-bearing system is further investigated to examine the failure mechanism of the critical load.

  3. Frictional Characteristics of Thrust Bearing in Scroll Compressor (United States)

    Sato, Hajime; Itoh, Takahide; Kobayashi, Hiroyuki

    This paper presents frictional characteristics of thrust bearing in scroll compressor focusing on the behavior of sliding portion which affects the generation of oil film. The coefficient of friction and tilt angle of sliding portion in the thrust bearing are obtained through both elemental friction test and cylinder pressure measurement of actual scroll compressor. Both tests showed that the coefficient of friction in low contact pressure rose with increase of tilt angle of sliding portion. The value of contact pressure which the coefficient of friction turns into increase was in agreement of the value which tilt angle become to increase. Numerical analysis using mixed lubrication theory was also performed. Analytical result indicated the same characteristics as the experiments, and the correlation between the coefficient of friction and the behavior of sliding portion was confirmed. Based on the experimental and the analytical results obtained here, the optimization of thrust bearing for commercial scroll compressor was applied. 2% improvement of total efficiency in rated condition was archived by optimization of thrust bearing.

  4. Experimental investigation on a high subsonic compressor cascade flow

    Directory of Open Access Journals (Sweden)

    Zhang Haideng


    Full Text Available With the aim of deepening the understanding of high-speed compressor cascade flow, this paper reports an experimental study on NACA-65 K48 compressor cascade with high subsonic inlet flow. With the increase of passage pressurizing ability, endwall boundary layer behavior is deteriorated, and the transition zone is extended from suction surface to the endwall as the adverse pressure gradient increases. Cross flow from endwall to midspan, mixing of corner boundary layer and the main stream, and reversal flow on the suction surface are caused by corner separation vortex structures. Passage vortex is the main corner separation vortex. During its movement downstream, the size grows bigger while the rotating direction changes, forming a limiting circle. With higher incidence, corner separation is further deteriorated, leading to higher flow loss. Meanwhile, corner separation structure, flow mixing characteristics and flow loss distribution vary a lot with the change of incidence. Compared with low aspect-ratio model, corner separation of high aspect-ratio model moves away from the endwall and is more sufficiently developed downstream the cascade. Results obtained present details of high-speed compressor cascade flow, which is rare in the relating research fields and is beneficial to mechanism analysis, aerodynamic optimization and flow control design.

  5. High-energy pulse compressor using self-defocusing spectral broadening in anomalously dispersive media

    DEFF Research Database (Denmark)


    A method and a pulse compressor (1) for compressing an optical pulse, wherein the pulse compressor comprising a bulk quadratic nonlinear medium (2) adapted for generating a negative nonlinear phase variation on the optical pulse and having a negative group-velocity dispersion, and a dispersive un...... subsequently be compressed by providing normal dispersion. As KDP crystals can be glued together, large apertures of the pulse compressor are possible making this method suitable for pulse compression in Joule-class lasers....

  6. Performance and Operating Characteristics of a Novel Positive-Displacement Oil-Free CO2 Compressor


    Kurtulus, Orkan; YANG Bin; Lumpkin, Dominique; Eckhard A. Groll; Jestings, Lee; Conde, Ricardo


    Research activities towards developing CO2 compressors have increased drastically during the last couple years. Since the transcritical CO2 cycle operates at much higher absolute pressures as compared to the conventional vapor compression cycles, it is necessary to develop new compressors or modify existing ones. In this paper, a novel positive-displacement oil-free CO2 compressor will be introduced. The compressor’s mechanical linkage system will be described. In addition, preliminary compre...

  7. Noise analysis of fluid-valve system in a linear compressor using CAE

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jun Ho; Jeong, Weui Bong [Pusan National Univ., Busan (Korea, Republic of); Kim, Dang Ju [LOCUS Co., Ltd., Busan (Korea, Republic of)


    A linear compressor in a refrigerator uses piston motion to transfer refrigerant so its efficiency is higher than a previous reciprocal compressor. Because of interaction between refrigerant and valves system in the linear compressor, however, noise has been a main issue. In spite of doing many experimental researches, there is no way to rightly predict the noise. In order to solve this limitation, the CAE analysis is applied. For giving credit to these computational data, all of the data are experimentally validated.

  8. Refrigerator with variable capacity compressor and cycle priming action through capacity control and associated methods

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Alberto Regio; Litch, Andrew D.; Wu, Guolian


    A refrigerator appliance (and associated method) that includes a condenser, evaporator and a multi-capacity compressor. The appliance also includes a pressure reducing device arranged within an evaporator-condenser refrigerant circuit, and a valve system for directing or restricting refrigerant flow through the device. The appliance further includes a controller for operating the compressor upon the initiation of a compressor ON-cycle at a priming capacity above a nominal capacity for a predetermined or calculated duration.




  10. Computer-Aided Design System for CP Single-Screw Compressor

    Institute of Scientific and Technical Information of China (English)

    SHEN Jing-feng; YAO Fu-sheng


    To design various optimum parameters and simulate the working process of CP single-screw compressor,the Computer-Aided Design(CAD)system for the CP singlescrew compressor has been established.A new method based on computer graphics technology,database technology,object-oriented programming technology,and visual simulation technology has been adopted in this CAD system.The system has integrated solid modeling function with parameterization design function and animator simulation function based on analyzing the working principle of the CP single-screw compressor.The experimental results show fhat the CAD system for the CP single-screw compressor is practical and feasible.

  11. A miniature Rotary Compressor with a 1:10 compression ratio (United States)

    Dmitriev, Olly; Tabota, Eugene; Arbon EurIng, Ian; FIMechE, CEng


    Micro compressors have applications in medical devices, robotics and “nanosatellites”. The problem of active cooling for photo detectors in “nano-satellites” becomes more important because the majority of space missions target Earth observation, and passive cooling does not provide the required temperatures to achieve the desired SNR levels. Reciprocating compressors used in cryocoolers cause vibrations. VERT Rotors has built an ultralow-vibration rotary compressor with 40mm-long screws, and our prototype delivered 1:10 compression ratio. This “nano” compressor is a non-conventional conical type consisting of an Inner conical screw rotor revolving inside an Outer screw rotor.

  12. An Experimental Study of Three-Dimensional Characteristics of Turbulent Wakes of Axial Compressor Rotors

    Institute of Scientific and Technical Information of China (English)

    Hongwei MA; Haokang JIANG


    This paper presents an experimental investigation of the characteristics of three-dimensional turbulent wakes of an isolated axial compressor rotor and a single-stage axial compressor rotor. The wakes were measured from hub to tip using a single-slant hot-wire and a four-hole conical high frequency pressure probe. The experiments were made at both design and near stall conditions. Variations of mean velocities, total pressure, static pressure and turbulence stresses in the wakes are shown and interpreted. The experimental data from the isolated compressor rotor wake are compared with that from the single-stage compressor rotor.

  13. Development of a linear compressor for two-stage pulse tube cryocoolers

    Institute of Scientific and Technical Information of China (English)

    Peng-da YAN; Wei-li GAO; Guo-bang CHEN


    A valveless linear compressor was built up to drive a self-made two-stage pulse tube cryocooler. With a designed maximum swept volume of 60 cm~3, the compressor can provide the cryocooler with a pressure volume (PV) power of 400 W.Preliminary measurements of the compressor indicated that both an efficiency of 35%~55% and a pressure ratio of 1.3~1.4 could be obtained. The two-stage pulse tube cryocooler driven by this compressor achieved the lowest temperature of 14.2 K.

  14. Performance improvement of standard turbo-compressor; Han`yo turbo asshukuki no seino kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Hokari, T.; Hasegawa, K.; Ozaki, S.; Majima, K. [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan)


    Abradable materials are soft and cause no contact damage to the impeller of the turbo-compressor. Using such materials for the inlet casing facing to the impeller allows very small clearances between the impeller and inlet casing, thus improving the compressor efficiency by 10% over conventional types. Changing the area of abradable material applied to the inlet casing identified the optimum area in which decrease of the compressor surge margin is minimized and efficiency is improved by 10%. As a result, turbo-compressors have the best performance when the abradable materials are applied from the impeller outlet to two-thirds of the forward location of the inlet casing. (author)

  15. Analysis of an activated-carbon sorption compressor operating with gas mixtures (United States)

    Tzabar, N.; Grossman, G.


    Sorption compressors elevate the pressure of gases and can provide a more or less continuous mass flow. Unlike mechanical compressors, sorption compressors have no moving parts, and therefore do not emit vibrations and are highly reliable. There exist different sorption compressors for different operating conditions and various gases. However, there are no published reports of sorption compressors for mixed gases. Such compressors, among other applications, may drive mixed-refrigerant Joule-Thomson cryocoolers. The adsorption of mixed gases is usually investigated under steady conditions, mainly for storage and separation processes. However, the sorption process in a compressor goes through varying states and mass changes; therefore, it differs from the common mixed gases adsorption applications. In this research a numerical analysis for mixed gas sorption compressors is developed, based on pure gas adsorption characteristics and the ideal adsorbed solution theory. Two pure gas adsorption models are used for calculating the conditions of the adsorbed phase: Langmuir and Sips; and the Peng-Robinson equation of state is used to calculate the conditions of the vapor phase. Two mixtures are investigated; nitrogen-methane and nitrogen-ethane. Finally, the analysis is verified against experimental results. This research provides initiatory observation for mixed gases sorption compressor in which each component is differently adsorbed.

  16. Reforming Gas Acetylene and Ammonia Compressor%氨乙炔混合气压缩机改造

    Institute of Scientific and Technical Information of China (English)

    胡晓东; 陈妙芳; 王正鲁


    针对MW50/28-298型氨乙炔混合气无油润滑压缩机设计缺陷导致排气量不足、使用寿命短等问题进行了理论和实验分析,在此基础上,提出了对压缩机无油润滑、活塞体结构的改造。实践证明:改造后的压缩机其微量油润滑对混合气体质量无影响,各项性能指标优越设计要求,使用寿命大大提高,这说明改造压缩机微量油润滑及活塞体结构是符合氨乙炔混合气压缩机的设计要求。%We believe there are some deficiencies in the design of the MW50/28-298-type gas aetylene and amonia compressor with oil-free lubrication, for example lower air discharging capacity and short service life. Hence, we propose reforming the oil-free lubrication and piston structure of the gas aetylene and amonia compresso with theo- retical and experimental analysis. The experimental results show that a small quantity of lubrication oil contained in the compressor thus reformed has no influence on the mixed gas quality and that the reformed compressor's perform- ance is better than that of the existing design; thus its service life is greatly enhanced.

  17. FOREWORD: 9th International Conference on Compressors and their Systems (United States)

    Kovacevic, Ahmed, Prof


    The 9th International Conference on Compressors and their Systems will be held in London from 5th - 9th September 2015, and as its Chairman, it is my pleasure to welcome you. This series of conferences started in 1999 organised by the Fluid Machinery Group of the Institution of Mechanical Engineers (IMechE) but since 2009 it has been managed by City University London in conjunction with the IMechE and the Institute of Refrigeration, both of which have been very proactive in promoting it. The Organising committee is grateful for their support and continued encouragement. This year, after rigorous reviewing, we have accepted over 80 technical papers for publication, the highest number in the conference history. On behalf of the organising committee I would like to thank the reviewers for their hard work and assistance. In addition to the main technical sessions, this year we have introduced a third day, specifically for Industry, to consider technology, business and market drivers on compressor developments. The traditional series of the short courses is this year continuing prior to the main event with the second short course/forum on Computational Fluid Dynamics in rotating positive displacement machines. I would like to extend my special thanks to our main sponsors, Holroyd PTG, Howden and Kapp Niels for their continuing support for the conference. With their generous contributions we have managed to keep the conference fees at the same level as in 2013, despite extending it to 3 days and holding it outside the University this year. The welcome reception on Sunday 6th September 2015 is dedicated to the celebration of the 20th anniversary of the Centre for Positive Displacement Compressors Technology which was formed at City University in 1995 with support from the Royal Academy of Engineering and Holroyd; its main aim being to assist British manufacturers of screw compressors. The Centre has since made a significant impact on the screw compressor world, far beyond


    Crouse, J. E.


    The axial-flow compressor is used for aircraft engines because it has distinct configuration and performance advantages over other compressor types. However, good potential performance is not easily obtained. The designer must be able to model the actual flows well enough to adequately predict aerodynamic performance. This computer program has been developed for computing the aerodynamic design of a multistage axial-flow compressor and, if desired, the associated blading geometry input for internal flow analysis. The aerodynamic solution gives velocity diagrams on selected streamlines of revolution at the blade row edges. The program yields aerodynamic and blading design results that can be directly used by flow and mechanical analysis codes. Two such codes are TSONIC, a blade-to-blade channel flow analysis code (COSMIC program LEW-10977), and MERIDL, a more detailed hub-to-shroud flow analysis code (COSMIC program LEW-12966). The aerodynamic and blading design program can reduce the time and effort required to obtain acceptable multistage axial-flow compressor configurations by generating good initial solutions and by being compatible with available analysis codes. The aerodynamic solution assumes steady, axisymmetric flow so that the problem is reduced to solving the two-dimensional flow field in the meridional plane. The streamline curvature method is used for the iterative aerodynamic solution at stations outside of the blade rows. If a blade design is desired, the blade elements are defined and stacked within the aerodynamic solution iteration. The blade element inlet and outlet angles are established by empirical incidence and deviation angles to the relative flow angles of the velocity diagrams. The blade element centerline is composed of two segments tangentially joined at a transition point. The local blade angle variation of each element can be specified as a fourth-degree polynomial function of path distance. Blade element thickness can also be specified

  19. Variable-Speed Induction Motor Drives for Aircraft Environmental Control Compressors (United States)

    Mildice, J. W.; Hansen, I. G.; Schreiner, K. E.; Roth, M. E.


    New, more-efficient designs for aircraft jet engines are not capable of supplying the large quantities of bleed air necessary to provide pressurization and air conditioning for the environmental control systems (ECS) of the next generation of large passenger aircraft. System analysis and engineering have determined that electrically-driven ECS can help to maintain the improved fuel efficiencies; and electronic controllers and induction motors are now being developed in a NASA/NPD SBIR Program to drive both types of ECS compressors. Previous variable-speed induction motor/controller system developments and publications have primarily focused on field-oriented control, with large transient reserve power, for maximum acceleration and optimum response in actuator and robotics systems. The application area addressed herein is characterized by slowly-changing inputs and outputs, small reserve power capability for acceleration, and optimization for maximum efficiency. This paper therefore focuses on the differences between this case and the optimum response case, and shows the development of this new motor/controller approach. It starts with the creation of a new set of controller requirements. In response to those requirements, new control algorithms are being developed and implemented in an embedded computer, which is integrated into the motor controller closed loop. Buffered logic outputs are used to drive the power switches in a resonant-technology, power processor/motor-controller, at switching/resonant frequencies high enough to support efficient high-frequency induction motor operation at speeds up to 50,000-RPA

  20. Air Consumption Analysis of Air-Jet Weaving

    Directory of Open Access Journals (Sweden)



    Full Text Available In Textile industry, production is mostly key concern for Industry owner. This always has attracted researchers and machines manufacturers to make new developments in process and machines. Air-jet is one of the leading and successful highest productive weaving machines. However, it is now well established that due to add of charges of compressed air, manufacturing cost of air-jet weaving machine is higher as compared with rapier and projectile weaving machines. This is why countries having energy issues do not prefer air-jet weaving machines comparing projectile weaving machines. In this regard, several researchers and machine manufacturers have continuously been working to improve the efficiency of air-jet weft insertion. However, industry practice is as important as design made by researchers. The aim of this research is to investigate the air consumption of air-jet weaving on industrial scale practice. In this study, five weaving machine of same manufacturer and model were selected. It was observed that despite of manufacturing same quality of fabric, air consumption was varying almost in all weaving machines. Conventionally, mill workers adopt hit and trial practice in weaving industry including airpressure setting which leads to variation of nozzle pressure. Main reason of disparity of air consumption in air-jet weaving machines may be variation of distance from compressor to weaving machines, number of joints, un-necessary valve opening and pipes leakages cause an increase of compressed air consumption.

  1. Thermal Modelling for the Motor in Semi-hermetic Screw Refrigeration Compressor under Part-load Conditions


    Chen, Wenqing; Shen, Jiubing; He, Zhilong; Wu, Huagen; Xing, Ziwen


    Semi-hermetic screw refrigeration compressor is mostly driven by a three phase asynchronous induction motor with its squirrel cage rotor attached to the shaft of the compressor helical male rotor. The motor is cooled by low temperature refrigerant coming from evaporator before it is inspired into compressor suction port. In order to investigate cooling effects of the motor and performance of the compressor under part-load conditions, a lumped parameter model describing heat transfer character...

  2. A numerical strategy for modelling rotating stall in core compressors (United States)

    Vahdati, M.


    The paper will focus on one specific core-compressor instability, rotating stall, because of the pressing industrial need to improve current design methods. The determination of the blade response during rotating stall is a difficult problem for which there is no reliable procedure. During rotating stall, the blades encounter the stall cells and the excitation depends on the number, size, exact shape and rotational speed of these cells. The long-term aim is to minimize the forced response due to rotating stall excitation by avoiding potential matches between the vibration modes and the rotating stall pattern characteristics. Accurate numerical simulations of core-compressor rotating stall phenomena require the modelling of a large number of bladerows using grids containing several tens of millions of points. The time-accurate unsteady-flow computations may need to be run for several engine revolutions for rotating stall to get initiated and many more before it is fully developed. The difficulty in rotating stall initiation arises from a lack of representation of the triggering disturbances which are inherently present in aeroengines. Since the numerical model represents a symmetric assembly, the only random mechanism for rotating stall initiation is provided by numerical round-off errors. In this work, rotating stall is initiated by introducing a small amount of geometric mistuning to the rotor blades. Another major obstacle in modelling flows near stall is the specification of appropriate upstream and downstream boundary conditions. Obtaining reliable boundary conditions for such flows can be very difficult. In the present study, the low-pressure compression (LPC) domain is placed upstream of the core compressor. With such an approach, only far field atmospheric boundary conditions are specified which are obtained from aircraft speed and altitude. A chocked variable-area nozzle, placed after the last compressor bladerow in the model, is used to impose boundary

  3. Performance of G-M Cryocooler with Oil-Free Linear Compressor (United States)

    Maddocks, J. R.; Kashani, A.; Helvensteijn, B. P. M.; Hoch, D. W.; Nellis, G. F.; Corey, J. A.; James, E. L.; Rhoads, G. L.


    A completely oil-free compressor for use with GM cryocoolers has been designed, built, and tested. The compressor uses two, fully-balanced, STAR linear motors together with friction-free reed valves. This arrangement eliminates all possibility of oil contamination in the helium working fluid, and therefore also eliminates the regular servicing that is required by conventional GM compressors. The compressor delivers high-pressure flows comparable to those delivered by well-developed conventional compressors, and is designed to match the operating point pressures and flow for a Sumitomo model 408 cold head. The design of the compressor is briefly reviewed. The measured performance of the compressor when integrated with a Sumitomo model 408 GM cold head is presented. The performance is mapped as a function of the refrigeration load and temperature at both the first and second stage heat exchangers and is compared with the both the manufacturer specified performance and separate baseline tests for the same cold head integrated with a conventional oil-flooded GM compressor.

  4. Effective combination of on-site measurements and simulations for a reciprocating compressor system

    NARCIS (Netherlands)

    Eijk, A.; Egas, G.


    The capacity of two parallel operating BORSIG reciprocating compressors, installed at the OMV refinery in Vienna, had to be increased. TNO TPD was ordered to investigate the dynamic effects on compressors and pipe work due to the increased flow to avoid vibration and fatigue problems afterwards. For

  5. 46 CFR 154.315 - Cargo pump and cargo compressor rooms. (United States)


    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo pump and cargo compressor rooms. 154.315 Section... CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Ship Arrangements § 154.315 Cargo pump and cargo compressor rooms. (a) Cargo pump rooms and...

  6. Experimental Investigation of High-Pressure Steam-Induced Surge in a Transonic Compressor Stage (United States)


    phenomena that reduce the operational effectiveness of compressors and pose a considerable threat of damage to essential turbomachine components. In...interrupts the compressor flow field in a manner that leads to violent, periodically steady pressure oscillations in a turbomachine stage [7

  7. Economic benefits of CAD-models for compressor manifold vibration analyses according to API 618

    NARCIS (Netherlands)

    Eijk, A.; Samland, G.; Retz, N.; Sauter, D.


    Reciprocating compressors, including pulsation dampers and the connected pipe system, are often the heart of an installation and should therefore operate reliable. Compressor manifold vibrations can contribute to fatigue failure of the system which can lead to unsafe situations, loss of capacity and

  8. Field adjustments to solve vibration problems in a modified reciprocating compressor system

    NARCIS (Netherlands)

    Eijk, A.; Gast, S.; Rainer, P.


    Due to constantly tightening laws for the minimization of CO2 and the changes in process parameters, an existing reciprocating compressor of 160 kW had to be replaced by a larger one. The compressor system is installed at the TOTAL Refinery in the eastern part of Germany. For this purpose the custom

  9. System identification modeling and unstable behavior of the dynamics of flows within the tip region of an axial compressor blade passage (United States)

    Sterbentz, Dane M.; Prasai, Sujan; Hofle, Mary M.; Walters, Thomas; Lin, Feng; Li, Ji-chao; Bosworth, Ken; Schoen, Marco P.


    In recent years, the correlation coefficient of pressure data from the same blade passage in an axial compressor unit has been used to characterize the state of flow in the blade passage. In addition, the correlation coefficient has been successfully used as an indicator for active control action using air injection. In this work, the correlation coefficient approach is extended to incorporate system identification algorithms in order to extract a mathematical model of the dynamics of the flows within a blade passage. The dynamics analyzed in this research focus on the flow streams and pressure along the rotor blades as well as on the unsteady tip leakage flow from the rotor tip gaps. The system identification results are used to construct a root locus plot for different flow coefficients, starting far away from stall to near stall conditions. As the compressor moves closer to stall, the poles of the identified models move towards the imaginary axis of the complex plane, indicating an impending instability. System frequency data is captured using the proposed correlation based system identification approach. Additionally, an oscillatory tip leakage flow is observed at a flow coefficient away from stall and how this oscillation changes as the compressor approaches stall is an interesting result of this research. Comparative research is analyzed to determine why the oscillatory flow behavior occurs at a specific sensor location within the tip region of the rotor blade.

  10. Integrated Evaluation of Closed Loop Air Revitalization System Components (United States)

    Murdock, K.


    NASA s vision and mission statements include an emphasis on human exploration of space, which requires environmental control and life support technologies. This Contractor Report (CR) describes the development and evaluation of an Air Revitalization System, modeling and simulation of the components, and integrated hardware testing with the goal of better understanding the inherent capabilities and limitations of this closed loop system. Major components integrated and tested included a 4-Bed Modular Sieve, Mechanical Compressor Engineering Development Unit, Temperature Swing Adsorption Compressor, and a Sabatier Engineering and Development Unit. The requisite methodolgy and technical results are contained in this CR.

  11. A Frequency Model of Vibrational Processes in Gas-Turbine Drives of Compressor Stations of Main Gas Pipelines (United States)

    Chekardovskiy, M. N.; Chekardovskiy, S. M.; Razboynikov, A. A.; Ponomareva, T. G.


    At compressor stations, systematic measurements of noise and vibration of power equipment - gas compressor units - are carried out. The article presents basic equations for calculating natural and forced frequencies at which the main defects appear. According to the studied dependences, results of calculations are obtained on the following types of drives for gas-compressor units GTK-10-4, Avon-1534, DG-90.

  12. Evaluation of the performance and flow in an axial compressor (United States)

    Waddell, J. L.


    An experimental evaluation of the axial compressor test rig with one stage of symmetric blading was conducted to determine its suitability for studies of tip clearance effects. Measurements were made of performance parameters and internal flow fields. The configuration tested was found to be unsuitable due to poor flow from the inlet guide vanes, particularly near the tip region. Secondary flows and flaws in construction of the guide vanes were suggested as probable causes. Recommendations were made for a program to resolve the problem.

  13. Non-linear effects in bunch compressor of TARLA (United States)

    Yildiz, Hüseyin; Aksoy, Avni; Arikan, Pervin


    Transport of a beam through an accelerator beamline is affected by high order and non-linear effects such as space charge, coherent synchrotron radiation, wakefield, etc. These effects damage form of the beam, and they lead particle loss, emittance growth, bunch length variation, beam halo formation, etc. One of the known non-linear effects on low energy machine is space charge effect. In this study we focus on space charge effect for Turkish Accelerator and Radiation Laboratory in Ankara (TARLA) machine which is designed to drive InfraRed Free Electron Laser covering the range of 3-250 µm. Moreover, we discuss second order effects on bunch compressor of TARLA.

  14. Miniature high speed compressor having embedded permanent magnet motor (United States)

    Zhou, Lei (Inventor); Zheng, Liping (Inventor); Chow, Louis (Inventor); Kapat, Jayanta S. (Inventor); Wu, Thomas X. (Inventor); Kota, Krishna M. (Inventor); Li, Xiaoyi (Inventor); Acharya, Dipjyoti (Inventor)


    A high speed centrifugal compressor for compressing fluids includes a permanent magnet synchronous motor (PMSM) having a hollow shaft, the being supported on its ends by ball bearing supports. A permanent magnet core is embedded inside the shaft. A stator with a winding is located radially outward of the shaft. The PMSM includes a rotor including at least one impeller secured to the shaft or integrated with the shaft as a single piece. The rotor is a high rigidity rotor providing a bending mode speed of at least 100,000 RPM which advantageously permits implementation of relatively low-cost ball bearing supports.

  15. Numerical design optimization of compressor blade based on ADOP

    Institute of Scientific and Technical Information of China (English)


    An aerodynamic design optimization platform (ADOP) has been developed. The numerical optimization method is based on genetic algorithm (GA), Pareto ranking and fitness sharing technique. The platform was used for design optimization of the stator of an advanced transonic stage to seek high adiabatic efficiency. The compressor stage efficiency is increased by 0.502% at optimal point and the stall margin is enlarged by nearly 1.0% at design rotating speed. The flow fields of the transonic stage were simulated with FINE/Turbo software package. The optimization result indicates that the optimization platform is effective in 3D numerical design optimization problems.

  16. Compressors for natural refrigerants; Compressoren voor natuurlijke koudemiddelen

    Energy Technology Data Exchange (ETDEWEB)

    Infante Ferreira, C.A. [Technische Universiteit Delft TUD, Delft (Netherlands)


    A brief overview is given of a number of subjects discussed at the Gustav Lorentzen Conference, which was held at the Delft University of Technology, June 25-27, 2012, with regard to compressors for carbon dioxide systems, for hydrocarbon systems and for ammonia systems. [Dutch] Een kort overzicht wordt gegeven van een aantal onderwerpen die zijn besproken op de Gustav Lorentzen Conferentie met betrekking tot compressoren voor kooldioxide systemen, voor koolwaterstof systemen en voor ammoniak systemen. De conferentie werd gehouden in de Technische Universiteit Delft van 25-27 juni 2012.

  17. An Investigation on the Pin Bearings’ Optimization of a Hermetic Reciprocating Compressor (United States)

    Ozdemir, A. R.; Hacioglu, B.; Kasapoglu, E.


    A hermetic reciprocating compressor is the most energy consuming component of the refrigerators. Therefore performance improvement studies of the compressor play an important role to reduce overall energy consumption of the refrigerators. Design of bearings is one of the major study areas influencing reciprocating compressor performance. In this study crank pin and piston pin bearings in hermetic compressor applications are investigated and optimized. The effect of operating conditions, bearing offset between crank pin and piston pin, bearing clearance and bearing location along the shaft on the friction loss were investigated and optimal bearing designs were developed. Efficiency measurements of the compressor showed that the improved crank pin and piston pin bearing designs provide up to 3.8% increase in the COP as a result of reduction in mechanical loss that is significantly influenced by the length of the bearings, bearing location along the shaft and operating conditions.

  18. Development of a test rig for a helium twin-screw compressor (United States)

    Wang, B. M.; Hu, Z. J.; Zhang, P.; Li, Q.


    A large helium cryogenic system is being developed for use in great science projects, such as the International Thermonuclear Experimental Reactor (ITER), Large Helical Device (LHD), and the Experimental Advanced Superconducting Tokamak (EAST). In this cryogenic system, a twin-screw compressor is a key component. Therefore, it is necessary to obtain the compressor performance. To obtain the performance characteristics, a test rig for the compressor has been built. All the important performance parameters, including adiabatic efficiency, volumetric efficiency, oil injection characteristic, and noise characteristic can be acquired with the rig when sensors are installed in the test system. With the test performance, the helium twin-screw compressor can be evaluated. Using these results, the design of the compressor can be improved.

  19. Updating temperature monitoring on reciprocating compressor connecting rods to improve reliability

    Directory of Open Access Journals (Sweden)

    Jim Townsend


    The compressors are used to move CO2 and boost the gas to the required field pressure, usually around 2,200 psig. Reciprocating compressors are flexible and able to handle wide capacity and condition swings, offer an efficient method of compressing almost any gas composition in a wide range of pressures and have numerous applications and wide power ratings. This makes them a vital component in various industrial facilities. Condition monitoring of critical rotating machinery is widely accepted by operators of centrifugal compressors. However, condition monitoring of reciprocating machinery such as compressors and internal combustion engines has not received the same degree of acceptance. This paper examines the reliability impact as a result of upgrading the temperature monitoring devices on the connecting rods of electric driven reciprocating compressors. A cost analysis is also presented to demonstrate that the upgrade in hardware and software will eventually yield a saving in the operating cost.

  20. NASA Environmentally Responsible Aviation High Overall Pressure Ratio Compressor Research Pre-Test CFD (United States)

    Celestina, Mark L.; Fabian, John C.; Kulkarni, Sameer


    This paper describes a collaborative and cost-shared approach to reducing fuel burn under the NASA Environmentally Responsible Aviation project. NASA and General Electric (GE) Aviation are working together aa an integrated team to obtain compressor aerodynamic data that is mutually beneficial to both NASA and GE Aviation. The objective of the High OPR Compressor Task is to test a single stage then two stages of an advanced GE core compressor using state-of-the-art research instrumentation to investigate the loss mechanisms and interaction effects of embedded transonic highly-loaded compressor stages. This paper presents preliminary results from NASA's in-house multistage computational code, APNASA, in preparation for this advanced transonic compressor rig test.

  1. Establishing a Ballistic Test Methodology for Documenting the Containment Capability of Small Gas Turbine Engine Compressors (United States)

    Heady, Joel; Pereira, J. Michael; Ruggeri, Charles R.; Bobula, George A.


    A test methodology currently employed for large engines was extended to quantify the ballistic containment capability of a small turboshaft engine compressor case. The approach involved impacting the inside of a compressor case with a compressor blade. A gas gun propelled the blade into the case at energy levels representative of failed compressor blades. The test target was a full compressor case. The aft flange was rigidly attached to a test stand and the forward flange was attached to a main frame to provide accurate boundary conditions. A window machined in the case allowed the projectile to pass through and impact the case wall from the inside with the orientation, direction and speed that would occur in a blade-out event. High-peed, digital-video cameras provided accurate velocity and orientation data. Calibrated cameras and digital image correlation software generated full field displacement and strain information at the back side of the impact point.

  2. Experimental investigation of a CO{sub 2} automotive air conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hongsheng; Chen, Jiangping; Chen, Zhijiu [Institute of Refrigeration and Cryogenics Engineering, Shanghai Jiao Tong University, Shanghai 200030 (China)


    In this study, a CO{sub 2} automotive air conditioner prototype was designed and constructed. The compressor was of swash plate design; the gas cooler and evaporator were made of fin-tubes; a manual expansion valve and an internal heat exchanger accumulator were used. The lubricant, the CO{sub 2} charge, the evaporator outlet pressure, the compressor speed, the air inlet temperature and flow rate of the gas cooler and the air flow rate of the evaporator were varied and the performance of the prototype was experimentally investigated in detail. The cooling capacity, compressor power consumption, CO{sub 2} mass flow rate, and COP value were analyzed. The experimental results showed that the CO{sub 2} system performance was greatly affected by different lubricants; the CO{sub 2} system performance was sensitive to the mass charge; the high side pressure affected the system performance greatly and a high side pressure controller was needed. (author)

  3. Method for evaluating the reliability of compressor impeller of turbocharger for vehicle application in plateau area (United States)

    Wang, Zheng; Wang, Zengquan; Wang, A.-na; Zhuang, Li; Wang, Jinwei


    As turbocharging diesel engines for vehicle application are applied in plateau area, the environmental adaptability of engines has drawn more attention. For the environmental adaptability problem of turbocharging diesel engines for vehicle application, the present studies almost focus on the optimization of performance match between turbocharger and engine, and the reliability problem of turbocharger is almost ignored. The reliability problem of compressor impeller of turbocharger for vehicle application when diesel engines operate in plateau area is studied. Firstly, the rule that the rotational speed of turbocharger changes with the altitude height is presented, and the potential failure modes of compressor impeller are analyzed. Then, the failure behavior models of compressor impeller are built, and the reliability models of compressor impeller operating in plateau area are developed. Finally, the rule that the reliability of compressor impeller changes with the altitude height is studied, the measurements for improving the reliability of the compressor impellers of turbocharger operating in plateau area are given. The results indicate that when the operating speed of diesel engine is certain, the rotational speed of turbocharger increases with the increase of altitude height, and the failure risk of compressor impeller with the failure modes of hub fatigue and blade resonance increases. The reliability of compressor impeller decreases with the increase of altitude height, and it also decreases as the increase of number of the mission profile cycle of engine. The method proposed can not only be used to evaluating the reliability of compressor impeller when diesel engines operate in plateau area but also be applied to direct the structural optimization of compressor impeller.

  4. Comparative Study of Unsteady Flows in a Transonic Centrifugal Compressor with Vaneless and Vaned Diffusers

    Directory of Open Access Journals (Sweden)

    Cui Michael M.


    Full Text Available To reduce vibration and noise level, the impeller and diffuser blade numbers inside an industrial compressor are typically chosen without common divisors. The shapes of volutes or collectors in these compressors are also not axis-symmetric. When impeller blades pass these asymmetric structures, the flow field in the compressor is time-dependent and three-dimensional. To obtain a fundamental physical understanding of these three-dimensional unsteady flow fields and assess their impact on the compressor performance, the flow field inside the compressors needs to be studied as a whole to include asymmetric and unsteady interaction between the compressor components. In the current study, a unified three-dimensional numerical model was built for a transonic centrifugal compressor including impeller, diffusers, and volute. HFC 134a was used as the working fluid. The thermodynamic and transport properties of the refrigerant gas were modeled by the Martin-Hou equation of state and power laws, respectively. The three-dimensional unsteady flow field was simulated with a Navier-Stokes solver using the k−ϵ turbulent model. The overall performance parameters are obtained by integrating the field quantities. Both the unsteady flow field and the overall performance are analyzed comparatively for each component. The compressor was tested in a water chiller system instrumented to obtain both the overall performance data and local flow-field quantities. The experimental and numerical results agree well. The correlation between the overall compressor performance and local flow-field quantities is defined. The methodology developed and data obtained in these studies can be applied to the centrifugal compressor design and optimization.

  5. Investigation on wind energy-compressed air power system

    Institute of Scientific and Technical Information of China (English)

    贾光政; 王宣银; 吴根茂


    Wind energy is a pollution free and renewable resource widely distributed over China. Aimed at protecting the environment and enlarging application of wind energy, a new approach to application of wind energy by using compressed air power to some extent instead of electricity put forward. This includes: explaining the working principles and characteristics of the wind energy-compressed air power system; discussing the compatibility of wind energy and compressor capacity; presenting the theoretical model and computational simulation of the system. The obtained compressor capacity vs wind power relationship in certain wind velocity range can be helpful in the designing of the wind power-compressed air system. Results of investigations on the application of high-pressure compressed air for pressure reduction led to conclusion that pressure reduction with expander is better than the throttle regulator in energy saving.

  6. Erosion-resistant coatings for gas turbine compressor blades (United States)

    Muboyadzhyan, S. A.


    The effect of ion-plasma coatings made from high-hardness metal compounds on the erosion and corrosion resistance and the mechanical properties of alloy (substrate) + coating compositions is comprehensively studied. The effects of the thickness, composition, deposition conditions, and design of coatings based on metal nitrides and carbides on the relative gas-abrasive wear of alloy + coating compositions in a gas-abrasive flux are analyzed. The flux contains quartz sand with an average fraction of 300-350 μm; the abrasive feed rate is 200 g/min; and the angles of flux incidence are 20° (tangential flow) and 70° (near-head-on attack flow). Alloy + coating compositions based on VN, VC, Cr3C2, ZrN, and TiN coatings 15-30 μ m thick or more are shown to have high erosion resistance. A detailed examination of the coatings with high erosion resistance demonstrates that a zirconium nitride coating is most appropriate for protecting gas turbine compressor blades made of titanium alloys; this coating does not decrease the fatigue strength of these alloys. A chromium carbide coating is the best coating for protecting compressor steel blades.

  7. Flow and Performance Calculations of Axial Compressor near Stall Margin (United States)

    Hwang, Yoojun; Kang, Shin-Hyoung


    Three-dimensional flows through a Low Speed Research Axial Compressor were numerically conducted in order to estimate the performance through unsteady and steady-state simulations. The first stage with the inlet guide vane was investigated at the design point to confirm that the rotor blade induced periodicity exists. Special attention was paid to the flow near the stall condition to inspect the flow behavior in the vicinity of the stall margin. The performance predicted under the steady-state assumption is in good agreement with the measured data. However, the steady-state calculations induce more blockage through the blade passage. Flow separations on the blade surface and end-walls are reduced when unsteady simulation is conducted. The negative jet due to the wake of the rotor blade periodically distorts the boundary layer on the surface of the stator blade and improves the performance of the compressor in terms of the pressure rise. The advantage of the unsteadiness increases as the flow rate reduces. In addition, the rotor tip leakage flow is forced downstream by the unsteadiness. Consequently, the behavior contributes to extending the range of operation by preventing the leakage flow from proceeding upstream near the stall margin.

  8. Controlling Compressor Vane Flow Vectoring Angles at Transonic Speeds (United States)

    Munson, Matthew; Rempfer, Dietmar; Williams, David; Acharya, Mukund


    The ability to control flow separation angles from compressor inlet guide vanes with a Coanda-type actuator is demonstrated using both wind tunnel experiments and finite element simulations. Vectoring angles up to 40 degrees from the uncontrolled baseline state were measured with helium schlieren visualization at transonic Mach numbers ranging from 0.1 to 0.6, and with airfoil chord Reynolds numbers ranging from 89,000 to 710,000. The magnitude of the vectoring angle is shown to depend upon the geometry of the trailing edge, and actuator slot size, and the momentum flux coefficient. Under certain conditions the blowing has no effect on the vectoring angle indicating that the Coanda effect is not present. DNS simulations with the finite element method investigated the effects of geometry changes and external flow. Continuous control of the vectoring angle is demonstrated, which has important implications for application to rotating machinery. The technique is shown to reduce the stall flow coefficient by 15 percent in an axial flow compressor.

  9. Numerical simulation of compressor endwall and casing treatment flow phenomena (United States)

    Crook, A. J.; Greitzer, E. M.; Tan, C. S.; Adamczyk, J. J.


    A numerical study is presented of the flow in the endwall region of a compressor blade row, in conditions of operation with both smooth and grooved endwalls. The computations are first compared to velocity field measurements in a cantilevered stator/rotating hub configuration to confirm that the salient features are captured. Computations are then interrogated to examine the tip leakage flow structure since this is a dominant feature of the endwall region. In particular, the high blockage that can exist near the endwalls at the rear of a compressor blade passage appears to be directly linked to low total pressure fluid associated with the leakage flow. The fluid dynamic action of the grooved endwall, representative of the casing treatments that have been most successful in suppressing stall, is then simulated computationally and two principal effects are identified. One is suction of the low total pressure, high blockage fluid at the rear of the passage. The second is energizing of the tip leakage flow, most notably in the core of the leakage vortex, thereby suppressing the blockage at its source.

  10. Preliminary measurements of aerodynamic damping of a transonic compressor rotor (United States)

    Crawley, E. F.; Kerrebrock, J. L.; Dugundji, J.


    The aeroelastic behavior of a transonic compressor rotor operated in the MIT Blowdown Compressor Facility has been examined by means of piezoelectric motion sensors at the base of each of the 23 blades. Excitation has been observed due to rotating stall, due to an incipient flutter, and due to the facility startup transient. A method has been found for determining the aerodynamic damping force by modal analysis of the blade motion. Application of this technique to the example of excitation by rotating stall has led to the conclusions that the blade loading decreases in the stall cell, and that the damping force on the blades in the clean flow is in phase with blade velocity but opposite it in sign, leading to a logarithmic decrement of 0.2. This method of force derivation has quite general applicability as it requires only blade motion data such as are routinely acquired with strain gages. It is argued that models are needed for aerodynamic damping which focus on the effects of near neighbors of a given blade, since flutter often results in large response of isolated blades or small groups of blades.

  11. Detector for flow abnormalities in gaseous diffusion plant compressors (United States)

    Smith, S.F.; Castleberry, K.N.


    A detector detects a flow abnormality in a plant compressor which outputs a motor current signal. The detector includes a demodulator/lowpass filter demodulating and filtering the motor current signal producing a demodulated signal, and first, second, third and fourth bandpass filters connected to the demodulator/lowpass filter, and filtering the demodulated signal in accordance with first, second, third and fourth bandpass frequencies generating first, second, third and fourth filtered signals having first, second, third and fourth amplitudes. The detector also includes first, second, third and fourth amplitude detectors connected to the first, second, third and fourth bandpass filters respectively, and detecting the first, second, third and fourth amplitudes, and first and second adders connected to the first and fourth amplitude detectors and the second and third amplitude detectors respectively, and adding the first and fourth amplitudes and the second and third amplitudes respectively generating first and second added signals. Finally, the detector includes a comparator, connected to the first and second adders, and comparing the first and second added signals and detecting the abnormal condition in the plant compressor when the second added signal exceeds the first added signal by a predetermined value. 6 figs.

  12. Elastoplastic frictional contact problem study on interference fits of compressor

    Institute of Scientific and Technical Information of China (English)

    Hongwu ZHANG; Aihua LIAO; Changhua WU


    The FE parametric quadratic programming (PQP) method developed from the parametric variational principle (PVP) was used for the analysis of the stress distribution of the 3D elastoplastic frictional contact of an impeller-shaft sleeve-shaft. A locomotive-type turbo-charger compressor with 24 blades under combined cen-trifugal and interference-fit loading was considered in the numerical analysis. The solution of elastoplastic frictional contact problems belongs to unspecified boundary pro-blems where the interaction between two kinds of nonli-nearities should occur. To save time in the numerical computation, a multi-substructure technique was adopted in the structural modeling. The effect of fit tolerance, wall thickness of the shaft sleeve, and rotational speed on the contact stress was discussed in detail in the numerical computation. To decrease the difficulty of the assembly process and ensure the safety of the working state, the amount of interference between the shaft sleeve and shaft by press-fitting should be controlled strictly to avoid the rapid increase of contact stress. The numerical results show that the algorithm has high accuracy and good con-vergence. The study can be referred to in deciding the proper fit tolerance and improving the design and man-ufacturing technology of compressor impellers.

  13. Study on the Utilization of Inter-stage Waste Heat of Nitrogen and Hydrogen Compressor in Synthesis Ammonia Plant%合成氨厂氮氢气压缩机级间废热利用技术研究

    Institute of Scientific and Technical Information of China (English)

    高伟; 王振辉; 李娜


    提出了一种利用多级压缩机级间的废热,采用溴化锂吸收式制冷,来降低压缩机一级入口气体的温度的方法,达到了增加压缩机排气量的目的.并对系统进行了建模与模拟,当采用三段废热时,可将压缩机入口气体温度由35℃降到15℃.提高产能10%左右.%The method was put torword that it can reduce the temperature of compressor inlet gas and get the purpose of increasing compressor air displacement by using lithium bromide absorption chiller and the waste heat of multi-stage compressor interstage. The modeling and simulation of system are conducted. When three-stage waste heat is used, the temperature of compressor inlet gas can drop from 35℃ to 15℃. The productivity therefor can increase by about 10%.

  14. Characteristics of heat transfer from the working medium to the case of an axial-flow compressor (United States)

    Lokai, V. I.; Karimova, A. G.; Prokopev, V. I.

    The heat transfer from the working medium to the case of an axial-flow compressor is investigated experimentally over a wide range of rpm (7000-17,000), air flow rates, and radial clearances between the case and the rotor. A nonuniform distribution of heat transfer coefficients over different parts of the case is observed for all the operating conditions investigated. Maximum heat transfer coefficients have been measured over the rotor near the exit; somewhat lower heat transfer coefficients have been recorded in the radial clearance behind the rotor; and still lower heat transfer coefficients have been observed at the ends of the interblade channels of the guide vanes and in the radial clearance behind them.

  15. 变频压缩机隔音棉应用研究%Research on Deadening Felt of Inverter Compressor

    Institute of Scientific and Technical Information of China (English)

    薛寒冬; 赖鑫; 张仕强; 任小辉


    本文主要通过对变频压缩机隔音棉性能测试、数据对比分析,结合实际测试效果及材料成本等,阐述了变频压缩机隔音棉的设计要求、降噪效果,及其在空调产品上推广应用的重要意义。%In this paper, the design requirements, noise reduction effect, and the significance of popularization and ap-plication of deadening felt of inverter compressor in air-conditioner products have been expounded, by conducting its performance test, data comparison analysis, and combining the actual test result as well as material cost control.

  16. Cryogenic hydrogen-induced air liquefaction technologies (United States)

    Escher, William J. D.


    Extensively utilizing a special advanced airbreathing propulsion archives database, as well as direct contacts with individuals who were active in the field in previous years, a technical assessment of cryogenic hydrogen-induced air liquefaction, as a prospective onboard aerospace vehicle process, was performed and documented. The resulting assessment report is summarized. Technical findings are presented relating the status of air liquefaction technology, both as a singular technical area, and also that of a cluster of collateral technical areas including: compact lightweight cryogenic heat exchangers; heat exchanger atmospheric constituents fouling alleviation; para/ortho hydrogen shift conversion catalysts; hydrogen turbine expanders, cryogenic air compressors and liquid air pumps; hydrogen recycling using slush hydrogen as heat sink; liquid hydrogen/liquid air rocket-type combustion devices; air collection and enrichment systems (ACES); and technically related engine concepts.

  17. Effects of Vortex Generator Jet on Corner Separation/Stall in High-Turning Compressor Cascade

    Institute of Scientific and Technical Information of China (English)

    刘华坪; 李得英; 陈焕龙; 张东飞


    The effects of the vortex generator jet(VGJ)attached at the endwall on the corner separation/stall con-trol are investigated by numerical simulation in a high-turning linear compressor cascade. The results show that the corner separation could be reduced significantly, which results in a wider operation range as well as a more uniform exit flow angle and total pressure profile. At the near-stall operation point, the maximum relative reduction of the total pressure loss is up to 32.5%,, whereas the jet mass ratio is less than 0.4%,. Based on the analysis of the detailed flow structure, three principal effects of the VGJ on the endwall cross flow and corner separation are identified. One is to increase the tangential velocity component opposite to cross flow, thus inhibiting the endwall secondary flow near the jet exit. The second is to suppress the pitchwise extension of the passage vortex as an air fence. The third is to sweep the low energy fluids towards the mainstream on the up-washed side and to transport the mainstream flu-ids to the endwall to reenergize the boundary layer on the down-washed side.

  18. Torsional Vibration Analysis of Reciprocating Compressor Trains driven by Induction Motors (United States)

    Brunelli, M.; Fusi, A.; Grasso, F.; Pasteur, F.; Ussi, A.


    The dynamic study of electric motor driven compressors, for Oil&Gas (O&G) applications, are traditionally performed in two steps separating the mechanical and the electrical systems. The packager conducts a Torsional Vibration Analysis (TVA) modeling the mechanical system with a lumped parameter scheme, without taking into account the electrical part. The electric motor supplier later performs a source current pulsation analysis on the electric motor system, based on the TVA results. The mechanical and the electrical systems are actually linked by the electromagnetic effect. The effect of the motor air-gap on TVA has only recently been taken into account by adding a spring and a damper between motor and ground in the model. This model is more accurate than the traditional one, but is applicable only to the steady-state condition and still fails to consider the reciprocal effects between the two parts of the system. In this paper the torsional natural frequencies calculated using both the traditional and the new model have been compared. Furthermore, simulation of the complete system has been achieved through the use of LMS AMESim, multi-physics, one-dimensional simulation software that simultaneously solves the shafts rotation and electric motor voltage equation. Finally, the transient phenomena that occur during start-up have been studied.

  19. The Response of a Low Speed Compressor on Rotating Inlet Distortion

    Institute of Scientific and Technical Information of China (English)

    Chaoqun NIE; Jingxuan ZHANG; Zhiting TONG; Hongwu ZHANG


    In multi-spool engines,the downstream compressor experiences a rotating inlet distortion if rotating stall occurs in upstream compressor,which may induce the instability of the whole compressor.In this paper,the compressor dynamic behavior is the major focus.The experiment was carried out on a single-stage low-speed axial-flow compressor.A rotating distortion generator equipped with different distortion sector(s) was designed to produce different rotating inlet distortion clockwise or counterclockwise with up to 100% of the compressor design speed.The distortion sector can be installed single or in some combination such as four sectors together.Three types of distortion sector/combination are used in the research work,which are single 30 degree sector,four 30 degree sectors and single 120 degree sector.It is found that the total pressure loss caused by rotating sector(s) increases when the distortion speed rises.For co-rotating distortions,all the three types of inlet distortion exhibited a peak in stall margin degradation when the distortion speed corresponded to roughly 50% of rotor speed.The two-dimensional numerical simulations of the compressor flow field clearly show the propagation of the disturbances trigged by the distortion sector(s).

  20. Observation of Oil Flow Characteristics in Rolling Piston Rotary Compressor for Reducing Oil Circulation Rate (United States)

    Song, S. j.; Noh, K. Y.; Min, B. C.; Yang, J. S.; Choi, G. M.; Kim, D. J.


    The oil circulation rate (OCR) of the rolling piston rotary compressor is a significant factor which affects the performance of refrigeration system. The increase of oil discharge causes decreasing of the heat transfer efficiency in the heat exchanger, pressure drop and lack of oil in lubricate part in compressor. In this study, the internal flow of compressor was visualized to figure out the oil droplet flow characteristics. The experiments and Computational Fluid Dynamics (CFD) simulations were conducted in various frequency of compressor to observe the effect of operation frequency on oil droplet flow characteristics for reducing OCR. In situ, measurement of oil droplet diameter and velocity were conducted by using high speed image visualization and Particle Image Velocimetry (PIV). The flow paths were dominated by copper wire parts driving the motor which was inserted in compressor. In order to verify the reliability of CFD simulation, the tendency of oil flow characteristics in each flow path and the compressor operating conditions were applied in CFD simulation. For reducing OCR, the structure such as vane, disk and ring is installed in the compressor to restrict the main flow path of oil particle. The effect of additional structure for reducing OCR was evaluated using CFD simulation and the results were discussed in detail.

  1. Development of a linear compressor for compact 2 K Gifford- McMahon cryocoolers (United States)

    Hiratsuka, Y.


    Recently, a new, compact Gifford-McMahon (GM) cryocooler for cooling superconducting single photon detectors (SSPD) has been developed at Sumitomo Heavy Industries, Ltd. (SHI) [1, 2]. The objective is to reduce the total height of the expander by 33% relative to the existing RDK-101 GM expander and to reduce the total volume of the compressor unit by 50% relative to the existing CNA-11 compressor. In addition, considering the targeted cooling application, we set the design temperature targets of the first and the second stages to 1 W and 20 mW of heat load at 60 K and 2.3 K, respectively. Although optimization of the internal components is one way to miniaturize the volume of the compressor unit, major design changes are required because the volume of the adsorber and the oil separator is almost the same as the volume of the compressor capsule. Thus, one approach is to develop a non-lubricated compressor, such as a valved linear compressor. An experimental unit of a valved linear compressor was designed and built, and preliminary experiments were conducted. Under no-load condition, a low temperature of 2.19 K has been achieved. With 1 W and 14 mW heat load, the temperature is 48 K at the first stage and 2.3 K at the second stage, with an input power of about 1.2 KW. The detailed experimental results will be discussed in this paper.

  2. Study and Design of a Linear Compressor of Voice-Coil Typ

    Directory of Open Access Journals (Sweden)

    VADAN, I.


    Full Text Available The paper presents the design and Finite Element (FEM analysis of a Linear compressor of voice coil type (LCVCT. This kind of linear compressor will be used in a refrigerator equipment. It is well-known that the replacing of the rotating compressor from a classical refrigerator by a linear compressor leads to an efficiency improving wit about 5% by avoiding the piston side friction, which is very important because of the huge number of refrigerators in operation world-wide. The linear compressor refrigerator is already commercially available in South Korea, equipped with an electromagnetic (fix coil and moving permanent magnet linear compressor. This paper presents a new type of linear compressor - a voice-coil type (fixed permanent magnet and moving coil. The operation principle is the same as for electrodynamic vibrator or electro-dynamic loud-speaker. The designing with rare earth permanent magnet is not a simple problem, because of the nonlinear characteristic of rare earth magnets. A magneto-static FEM analysis has been performed in order to validate the design methodology proposed in the paper.

  3. Numerical investigation of diffuser solidity effect on turbulent airflow and performance of the turbocharger compressor

    Directory of Open Access Journals (Sweden)

    Chehhat A.


    Full Text Available Low solidity diffuser in centrifugal compressors can achieve both high efficiency and wide operating ranges which is of great importance for turbocharger compressor. Low solidity is achieved by using a low chord to pitch ratio. In this work, a CFD simulation is carried out to examine the effect of solidity on airflow field of a turbocharger centrifugal compressor which consists of a simple-splitter impeller and a vaned diffuser. By changing the number of diffuser vanes while keeping the number of impeller blades constant, the solidity value of the diffuser is varied. The characteristics of the compressor are evaluated for 6, 8, 10 and 12 stator vanes which correspond to solidity of: 0.78, 1.04, 1.29 and 1.55, respectively. The spatial distribution of the pressure, velocity and turbulent kinetic energy show that the diffuser solidity has significant effect on flow field and compressor performance map. The compressor with a 6 vanes diffuser has higher efficiency and operates at a wider range of flow rate relative to that obtained with larger vans number. However a non-uniform flow at the compressor exit was observed with relatively high turbulent kinetic energy.

  4. High Energy Efficiency Air Conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Edward McCullough; Patrick Dhooge; Jonathan Nimitz


    values agree well with previous results and computer simulations of Ikon B performance versus R-22. The lower cooling capacity of Ikon B is not a concern unless a particular air conditioner is near its maximum cooling capacity in application. Typically, oversized A/C systems are installed by contractors to cover contingencies. In the extended run with Ikon B, which lasted about 4.5 months at 100 deg F ambient temperature and 68% compressor on time, the air conditioner performed well with no significant loss of energy efficiency. Post-run analysis of the refrigerant, compressor lubricant oil, compressor, compressor outlet tubing, and the filter/dryer showed minor effects but nothing that was considered significant. The project was very successful. All objectives were achieved, and the performance of Ikon B indicates that it can easily be retrofitted into R-22 air conditioners to give 15 - 20% energy savings and a 1 - 3 year payback of retrofit costs depending on location and use. Ikon B has the potential to be a successful commercial product.

  5. Variable speed rotary compressor and adjustable speed drive efficiencies measured in the laboratory (United States)

    Miller, W. A.

    Two state-of-the-art variable-speed rotary compressors, of nominal one ton cooling capacity, were instrumented and tested in the laboratory. Both compressors were identical except for their respective variable-speed drive systems (i.e., motor and inverter). One compressor had an inverter driven induction motor (IDIM) drive, and the other had a permanent magnet electronically commutated motor drive (PM-ECM). The laboratory study evaluated the compressor's efficiency under representative variable-speed conditions. Testing was conducted as a function of compressor drive frequency and of refrigerant condensing and evaporating conditions. Saturated refrigerant conditions, inlet superheat, and subcooling were controlled using a secondary refrigerant calorimeter. Spectrum analysis was conducted on the current input to one phase of the three-phase drive systems to measure motor speed and characterize harmonic content of the inverters. An optimal volt per Hz ratio was determined at 120-, 90-, 60-, and 30-Hz drive frequencies and at different load conditions for the rotary with induction motor as driven by a PWM inverter and also by a motor generator set (ideal induction motor drive). Variation of voltage input to the compressor had the largest effect at the lowest drive frequency (30Hz). A 5 percent variation about the optimal voltage at 30 Hz frequency caused a roughly 5 percent drop in compressor isentropic efficiency. Calorimeter data were used to develop modulating compressor and drive system performance maps. Performances of the two compressors were compared and the rotary with PM-ECM drive showed better efficiency trends at 30-Hz drive frequency. Above the 30-Hz drive frequency no clear advantage was observed for the PM-ECM vs the IDIM, possibly due to oversizing of the PM-ECM inverter.

  6. Advanced industrial gas turbine technology readiness demonstration program. Phase II. Final report: compressor rig fabrication assembly and test

    Energy Technology Data Exchange (ETDEWEB)

    Schweitzer, J. K.; Smith, J. D.


    The results of a component technology demonstration program to fabricate, assemble and test an advanced axial/centrifugal compressor are presented. This work was conducted to demonstrate the utilization of advanced aircraft gas turbine cooling and high pressure compressor technology to improve the performance and reliability of future industrial gas turbines. Specific objectives of the compressor component testing were to demonstrate 18:1 pressure ratio on a single spool at 90% polytropic efficiency with 80% fewer airfoils as compared to current industrial gas turbine compressors. The compressor design configuration utilizes low aspect ratio/highly-loaded axial compressor blading combined with a centrifugal backend stage to achieve the 18:1 design pressure ratio in only 7 stages and 281 axial compressor airfoils. Initial testing of the compressor test rig was conducted with a vaneless centrifugal stage diffuser to allow documentation of the axial compressor performance. Peak design speed axial compressor performance demonstrated was 91.8% polytropic efficiency at 6.5:1 pressure ratio. Subsequent documentation of the combined axial/centrifugal performance with a centrifugal stage pipe diffuser resulted in the demonstration of 91.5% polytropic efficiency and 14% stall margin at the 18:1 overall compressor design pressure ratio. The demonstrated performance not only exceeded the contract performance goals, but also represents the highest known demonstrated compressor performance in this pressure ratio and flow class. The performance demonstrated is particularly significant in that it was accomplished at airfoil loading levels approximately 15% higher than that of current production engine compressor designs. The test results provide conclusive verification of the advanced low aspect ratio axial compressor and centrifugal stage technologies utilized.

  7. Stepless control system for reciprocating compressors: energy savings + process control improvement

    Energy Technology Data Exchange (ETDEWEB)

    Grande, Alvaro; Wenisch, Markus [Hoerbiger Ventilwerke GmbH and Co KG, Wien (Austria); Jacobs, Denis [HOERBIGER do Brasil Industria de Equipamentos, Cajamar, SP (Brazil)


    In the past, the capacity of reciprocating compressors was typically controlled by on/off unloaders (step-control) and recycle valves. But due to the fact that the power ratings of new reciprocating compressors for the oil and gas industry increase significantly, advanced control systems are required to reduce power costs and save energy. On top of that, multi-stage compressors are frequently integrated into complex process plants that demand precise control and operational flexibility. There are several solutions for this equation, but maybe the most successful is the use of the reverse flow principle applied to an electronically controlled and hydraulically actuated suction valve unloaders system. (author)

  8. Secondary flow, turbulent diffusion and mixing in axial-flow compressors (United States)

    Wisler, D. C.; Bauer, R. C.; Okiishi, T. H.


    The relative importance of convection by secondary flows and diffusion by turbulence as mechanisms responsible for mixing in multistage, axial-flow compressors has been investigated by using the ethylene tracer-gas technique and hot wire anemometry. The tests were conducted at two loading levels in a large, low-speed, four-stage compressor. The experimental results show that considerable cross-passage and spanwise fluid motion can occur and that both secondary flow and turbulent diffusion can play important roles in the mixing process, depending upon location in the compressor and loading level.

  9. Study of blade aspect ratio on a compressor front stage aerodynamic and mechanical design report (United States)

    Burger, G. D.; Lee, D.; Snow, D. W.


    A single stage compressor was designed with the intent of demonstrating that, for a tip speed and hub-tip ratio typical of an advanced core compressor front stage, the use of low aspect ratio can permit high levels of blade loading to be achieved at an acceptable level of efficiency. The design pressure ratio is 1.8 at an adiabatic efficiency of 88.5 percent. Both rotor and stator have multiple-circular-arc airfoil sections. Variable IGV and stator vanes permit low speed matching adjustments. The design incorporates an inlet duct representative of an engine transition duct between fan and high pressure compressor.

  10. Research and development on transonic compressor of high pressure ratio turbocharger for vehicle internal combustion engines

    Institute of Scientific and Technical Information of China (English)


    The pressure ratio required for a turbocharger centrifugal compressor increases with internal combustion engine power density. High pressure ratio causes a transonic flow field at the impeller inducer. Transonic flow narrows the stable flow range and de-teriorates stage efficiency. In this work, an advanced high pressure ratio transonic compressor was designed. The experimental results show that the maximum pressure ratio of this turbocharger is about 4.2, the maximum efficiency is above 80% and the stable flow range at the designed rotating speed is up to 34%. A turbocharger with this transonic compressor has been applied to some vehicle research actually, and improved power density by 40%.

  11. Numerical forecasting surge in a piping of compressor shops of gas pipeline network

    Institute of Scientific and Technical Information of China (English)


    This paper presents a method of forecasting stable operation of gas compressor unit (GCU) centrifugal supercharger (CFS) installed on a piping of compressor shops servicing gas pipelines. The stability of superchargers operation is assessed in relation to the phenomenon of surge. Solution of this problem amounts to the development and numerical analysis of a set of ordinary differential equations. The set describes transmission of gas through a compressor shop as a fluid dynamics model with lumped parameters. The proposed method is oriented to wide application by specialists working in the gas industry. The practical application of this method can use all-purpose programming and mathematical software available to specialists of gas companies.

  12. Overview of Air Liquide refrigeration systems between 1.8 K and 200 K

    Energy Technology Data Exchange (ETDEWEB)

    Gondrand, C.; Durand, F.; Delcayre, F.; Crispel, S. [AL-AT, 2 rue de Clémencières, 38360 Sassenage (France); Baguer, G. M. Gistau [CRYOGUY, 44, chemin de la Buisse, 38330 Biviers (France)


    Cryogenic refrigeration systems are necessary for numerous applications. Gas purification and distillation require temperatures between 15 K and 200 K depending on the application, space simulation chambers down to 15 K, superconductivity between 1.8 K and up to 75 K (magnets, cavities or HTS devices like cables, FCL, SMES, etc), Cold Neutron Sources between 15 and 20 K, etc. Air Liquide Advanced Technologies is designing and manufacturing refrigerators since 60 years to satisfy those needs. The step by step developments achieved have led to machines with higher efficiency and reliability. In 1965, reciprocating compressors and Joule Thomson expansion valves were used. In 1969, centripetal expanders began to be used. In 1980, oil lubricated screw compressors took the place of reciprocating compressors and a standard range of Claude cycle refrigerators was developed: the HELIAL series. 1980 was also the time for cryogenic centrifugal compressor development. In 2011, driven by the need for lower operational cost (high efficiency and low maintenance), cycle oil free centrifugal compressors on magnetic bearings were introduced instead of screw compressors. The power extracted by centripetal expanders was recovered. Based on this technology, a range of Turbo-Brayton refrigerators has been designed for temperatures between 40 K and 150 K. On-going development will enable widening the range of Turbo-Brayton refrigerators to cryogenic temperatures down to 15 K.. Cryogenic centrifugal circulators have been developed in order to answer to an increasing demand of 4 K refrigerators able to distribute cold power.

  13. Overview of Air Liquide refrigeration systems between 1.8 K and 200 K (United States)

    Gondrand, C.; Durand, F.; Delcayre, F.; Crispel, S.; Baguer, G. M. Gistau


    Cryogenic refrigeration systems are necessary for numerous applications. Gas purification and distillation require temperatures between 15 K and 200 K depending on the application, space simulation chambers down to 15 K, superconductivity between 1.8 K and up to 75 K (magnets, cavities or HTS devices like cables, FCL, SMES, etc), Cold Neutron Sources between 15 and 20 K, etc. Air Liquide Advanced Technologies is designing and manufacturing refrigerators since 60 years to satisfy those needs. The step by step developments achieved have led to machines with higher efficiency and reliability. In 1965, reciprocating compressors and Joule Thomson expansion valves were used. In 1969, centripetal expanders began to be used. In 1980, oil lubricated screw compressors took the place of reciprocating compressors and a standard range of Claude cycle refrigerators was developed: the HELIAL series. 1980 was also the time for cryogenic centrifugal compressor development. In 2011, driven by the need for lower operational cost (high efficiency and low maintenance), cycle oil free centrifugal compressors on magnetic bearings were introduced instead of screw compressors. The power extracted by centripetal expanders was recovered. Based on this technology, a range of Turbo-Brayton refrigerators has been designed for temperatures between 40 K and 150 K. On-going development will enable widening the range of Turbo-Brayton refrigerators to cryogenic temperatures down to 15 K.. Cryogenic centrifugal circulators have been developed in order to answer to an increasing demand of 4 K refrigerators able to distribute cold power.

  14. Energy storage by compressed air. [using windpowered pumps (United States)

    Szego, G. C.


    The feasibility of windpower energy storage by compressed air is considered. The system is comprised of a compressor, a motor, and a pump turbine to store air in caverns or aquifiers. It is proposed that storage of several days worth of compressed air up to 650 pounds per square inch can be used to push the aquifier up closer to the container dome and thus initiate piston action by simply compressing air more and more. More energy can be put into it by pressure increase or pushing back the water in the aquifier. This storage system concept has reheat flexibility and lowest cost effectiveness.

  15. Unsteady Tip Clearance Flow in an Isolated Axial Compressor Rotor

    Institute of Scientific and Technical Information of China (English)

    Hongwu ZHANG; Xiangyang DENG; Jingyi CHEN; Weiguang HUANG


    The paper investigates effects of operating conditions, tip clearance sizes and external unsteady excitations on the unsteady tip clearance flow in an isolated axial compressor rotor by unsteady 3D Navier-Stokes simulations. The results show that the unsteady tip clearance vortex takes a periodic flow behavior in the rotor tip region. With the decrease of the flow coefficient, the unsteady tip clearance vortex is enhanced and its frequency becomes lower. A larger tip clearance size can cause bigger unsteady fluctuation amplitude and a lower fluctuation frequency of the tip clearance vortex at the near stall operating condition. The unsteady excitation with the natural frequency of the tip clearance vortex can enhance the unsteadiness of the tip clearance vortex and improve the overall rotor performance. The frequency of the unsteady tip clearance vortex is independent of external unsteady excitations with different frequencies.

  16. Use of partially shrouded impeller in a small centrifugal compressor

    Institute of Scientific and Technical Information of China (English)

    Jin Tang; Teemu Turunen-Saaresti; Jaakko Larjola


    Numerical analysis is conducted for the 3-dimensional impeller and vaneless diffuser of a small centrifugal compressor. The influence of impeller tip clearance on the flow field of the impeller is investigated. Detailed investigation on the leaking flow across the tip clearance of the impeller shows that the leaking flow rate is higher near the exit of the impeller than that near the inlet of the impeller. Based on this phenomenon, a new partially shrouded impeller is designed. The impeller is shrouded near the exit of the impeller. Numerical results show that the secondary flow region becomes smaller at the exit of the impeller. Better performance is achieved than that with the unshrouded impeller.

  17. Thermodynamic Analysis of the Diabatic Efficiency of Turbines and Compressors

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kyoung Kuhn [Kookmin Univ., Seoul (Korea, Republic of)


    Thermodynamic analysis is conducted on the first-order approximation model for turbines and compressors. It is shown that the adiabatic efficiency could be greater than unity, depending on the entropic mean temperature, entropy generation, thermal reservoir temperature, and heat transfer. Therefore, adiabatic efficiency applied to a diabatic control volume results in an error overestimating its performance. To resolve this overestimation, it is suggested that a reversible diabatic process be referred to as an ideal process to evaluate diabatic efficiency . The diabatic efficiency suggested in this work is proven to always be less than unity and it is smaller than the exergy efficiency in most cases. The diabatic efficiency could be used as a more general definition of efficiency, which would include adiabatic efficiency.

  18. Operational Experience with a Cryogenic Axial-Centrifugal Compressor

    CERN Document Server

    Decker, L; Löhlein, K; Purtschert, W; Ziegler, B L; Lebrun, P; Tavian, L; Brunovsky, I; Tucek, L


    The Large Hadron Collider (LHC), presently under construction at CERN, requires large refrigeration capacity at 1.8 K. Compression of gaseous helium at cryogenic temperatures is therefore inevitable. Together with subcontractors, Linde Kryotechnik has developed a prototype machine. This unit is based on a cryogenic axial-centrifugal compressor, running on ceramic ball bearings and driven by a variable-frequency electrical motor operating at ambient temperature. Integrated in a test facility for superconducting magnets the machine has been commissioned without major problems and successfully gone through the acceptance test in autumn 1995. Subsequent steps were initiated to improve efficiency of this prototype. This paper describes operating experience gained so far and reports on measured performance prior to and after constructional modifications.

  19. Performance Characteristics of Absorption Hybrid Cycle Introduced Compressor (United States)

    Iyoki, Shigeki; Kotani, Yuji; Uemura, Tadashi

    In this paper, four kinds of absorption hybrid cycle which introduced the compressor in the absorption cycle were proposed. As basic cycle of absorption refrigerating machine, the following were chosen: two kinds of single-stage absorption refrigerating machine and two kinds of double effect absorption refrigerating machine. As a working medium-absorbent system, NH3-H2O system, C2H5NH2-H2O system and C2H5NH2-H2O-LiBr system were adopted. Using these three kinds of working medium-absorbent system, the performance characteristics of four kinds of absorption hybrid cycle were simulated. And the performance characteristics of these cycles were compared.

  20. Corrosion behavior of construction materials for ionic liquid hydrogen compressor

    DEFF Research Database (Denmark)

    Arjomand Kermani, Nasrin; Petrushina, Irina; Nikiforov, Aleksey Valerievich


    The corrosion behavior of various commercially available stainless steels and nickel-based alloys as possible construction materials for components which are in direct contact with one of five different ionic liquids was evaluated. The ionic liquids, namely: 1-ethyl-3-methylimidazolium triflate, 1...... liquid hydrogen compressor. An electrochemical cell was specially designed, and steady-state cyclic voltammetry was used to measure the corrosion resistance of the alloys in the ionic liquids at 23 °C, under atmospheric pressure. The results showed a very high corrosion resistance and high stability...... for all the alloys tested. The two stainless steels, AISI 316L and AISI 347 showed higher corrosion resistance compared to AISI 321 in all the ionic liquids tested. It was observed that small addition of molybdenum, tantalum, and niobium to the alloys increased the corrosion stability in the ionic liquids...

  1. Multi-objective optimization of an axial compressor blade

    Energy Technology Data Exchange (ETDEWEB)

    Samad, Abdus; Kim, Kwang Yong [Inha University, Incheon (Korea, Republic of)


    Numerical optimization with multiple objectives is carried out for design of an axial compressor blade. Two conflicting objectives, total pressure ratio and adiabatic efficiency, are optimized with three design variables concerning sweep, lean and skew of blade stacking line. Single objective optimizations have been also performed. At the data points generated by D-optimal design, the objectives are calculated by three-dimensional Reynolds-averaged Navier-Stokes analysis. A second-order polynomial based response surface model is generated, and the optimal point is searched by sequential quadratic programming method for single objective optimization. Elitist non-dominated sorting of genetic algorithm (NSGA-II) with {epsilon}-constraint local search strategy is used for multi-objective optimization. Both objective function values are found to be improved as compared to the reference one by multi-objective optimization. The flow analysis results show the mechanism for the improvement of blade performance

  2. Optimization of RF Compressor in the SPARX Injector

    CERN Document Server

    Ronsivalle, Concetta; Ferrario, Massimo; Serafini, Luca; Spataro, Bruno


    The SPARX photoinjector consists in a rf gun injecting into three SLAC accelerating sections, the first one operating in the RF compressor configuration in order to achieve higher peak current. A systematic study based on PARMELA simulations has been done in order to optimize the parameters that influence the compression also in view of the application of this system as injector of the so called SPARXINO 3-5 nm FEL test facility. The results of computations show that peak currents at the injector exit up to kA level are achievable with a good control of the transverse and longitudinal emittance by means of a short SW section operating at 11424 MHz placed before the first accelerating section. Some working points in different compression regimes suitable for FEL experiments have been selected. The stability of these points and the sensitivity to various types of random errors are discussed.

  3. Off-design performance prediction of Radial Compressor of Supercritical CO{sub 2} Brayton Cycle for KAIST Micro Modular Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Seongkuk; Lee, Jekyoung; Kim, Seong Gu; Lee, Jeong Ik [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)


    KAIST research team suggested a new concept of SMR, which utilizes S-CO{sub 2} as the operating fluid and coolant. It was named as KAIST MMR(Micro Modular Reactor). Compared with existing SMR concepts, this reactor has advantages of achieving smaller volume of power conversion unit (PCU) containing the core and PCU in one vessel for the complete modularization passive air-cooling system more flexible installation in the inland area. In previous study, performance of turbomachinery in PCU was considered only on-design. But, off-design performances of each component can affect not only PCU but also the core because this reactor adopts the direct S-CO{sub 2} loop in GFR. Nuclear system is applied by relatively conservative criteria of safety. Thus, off-design performances of each component should be considered in order to be more realistic reactor. The suggested turbomachinery size of the S-CO{sub 2} cycle is relatively smaller than those of helium Brayton cycle and steam Rankine cycle. Performance analysis of compressor is conducted by KAIST-TMD in case of on-design and off-design. Compressor efficiency in on-design conditions is obtained 84.51 %. But compressor performance in off-design conditions decreases certainly. This means that more heat than existing prediction is rejected by air-cooling system. KAIST-TMD will be verified with more experiment data for providing the results of more accurate analysis. Also, this code will be modified to couple with safety analysis codes and S-CO{sub 2} cycle analysis codes in the future. Furthermore, authors will consider aerodynamic performance analysis and various losses for more realization.

  4. Flow Characteristics of a Pipe Diffuser for Centrifugal Compressors

    Directory of Open Access Journals (Sweden)

    Zhenzhong Sun


    Full Text Available The pipe diffuser, an efficient kind of radial bladed diffuser, is widely used in centrifugal compressors for gas turbine engines. This paper investigates flow characteristics of a pipe diffuser for centrifugal compressors by solving three-dimensional Reynolds-averaged Navier-Stokes equations. The results show that the pipe diffuser is adaptable to high Mach number incoming flows, and its unique leading edge could uniform the flow distortion. Numerical analysis indicates that the choke in pipe diffuser occurs suddenly, which leads to the dramatically steep performance curves near choke condition. Besides, it is found that the first half flow passage is particularly important to the pipe diffuser performance as it influences the choking behavior, the static pressure distribution, and the matching, so more attention should be paid to this region when designing or optimizing a pipe diffuser. Two counter-rotating vortices generated in the diffuser inlet region are captured by numerical simulation, and they can exist in the downstream of the diffuser passage. More detailed analysis show that these two vortices dominate the flow structure in the whole diffuser passage by shifting flow to certain positions and forming high-momentum flow cells and wake flow cells. The leading edge formed by the intersection of adjacent diffuser passages significantly affects this pair of vortices. In addition, these two vortices also affect the flow separation in pipe diffuser flow passages, they suppress separation near the front wall and back wall while facilitate separation at center locations. Therefore, it is recommended to design the leading edge of the pipe diffuser carefully to control the vortices and obtain a better flow field.

  5. Technical and economic feasibility study of low flow compressors; Estudo de viabilidade tecnica e economica de compressores de baixa vazao

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Nagib F. da; Vieira, Francisco A. [Centro de Tecnologias do Gas (CTGAS), Natal, RN (Brazil); Campos, Michel F.; Moura, Newton R. de [PETROBRAS, Rio de Janeiro, RJ (Brazil)


    One of the main problems for the installation of new natural gas stations has been the high investment for compressor acquisition. Out of 900 thousand Reais, which is an average value for the construction of a supplying structure, 600 thousand are destined for the acquisition of the compression system (average outflow of 800 Nm{sup 3}/hour at 20 deg C, 1 atm), approach commonly used in Brazil. To be economically feasible, it is necessary that the fueling station has a supplying volume of at least 600 vehicles/day. Niches of NGV market have been identified to new potentials, where the compressed gas demand is lower, therefore not justifying an investment in compression systems of high capacity. A solution for reduction of this investment would be the introduction in the Brazilian market of compression systems of medium and low outflow and with lower cost. In this context, CTGAS has a project into RedeGasEnergia in partnership with PETROBRAS, funded by FINEP/CTPETRO, to develop, to acquire, and to mount prototypes of compression systems of small and medium capacities. To attend the objectives of this project, a compressor was developed in a partnership with a national manufacturer, MOVITEC, and participation of CENPES, with an outflow of 200 Nm{sup 3}/hour (at 20 deg C 1 atm.), for a demand of up to 200 vehicles/day. Another alternative, for the case of small consumers with supplying demand of up to 15 vehicles/day is being made possible by the introduction in the Brazilian market of two compression systems of outflow with up to 13,0 Nm{sup 3}/h (at 20 deg C 1 atm). The installation of these systems will assist in the economical and technical feasibility studies. At this moment, there are some companies interested in knowing this new technology for using the compressor in their installations, thus demonstrating the success of this project, as well as the wakening of a new consuming market. (author)

  6. Alternatives to HCFC-22 for air conditioners

    Energy Technology Data Exchange (ETDEWEB)

    Devotta, S. [Council of Scientific and Industrial Research, National Chemical Lab., Pune (India); Waghmare, A.V.; Domkundwar, B.M. [College of Engineering, Pune (India); Sawant, N.N. [National Inst. of Standards and Technology, Gaithersburg, MD (United States)


    Some selected fluids have been assessed for their suitability as alternatives to HCFC-22 for air conditioners. Only those refrigerants with zero ozone depletion potential are considered. NIST CYCLE{sub D} has been used for the comparative thermodynamic analysis. Among the refrigerants studied (HFC-134a, HC-290, R-407C, R-410A, and three blends of HFC-32, HFC-134a and HFC-125), HFC-134a offers the highest COP, but its capacity is the lowest and requires much larger compressors. The characteristics of HC-290 are very close to those of HCFC-22, and compressors require very little modification. Therefore, HC-290 is a potential candidate provided the risk concerns are mitigated as had been accomplished for refrigerators. For retrofitting, R-407C is probably the best candidate. (Author)

  7. Noise Reduction Analysis on Inverter Driven Two-Cylinder Rotary Compressor (United States)

    Nonaka, Ryutaro; Suda, Akihiro; Matumoto, Kenzou

    Two-cylinder rotary compressor is dynamically balanced well because two rollers in each cylinder chamber are located in opposite sides. Thus, it helps to reduce the circumferential vibration based on the tracking torque ripple for gas compression. This concept has been recently applied to room airconditioners (RACs) for the purpose of reducing vibration and noise of the unit. However, it consequently requires the compressor, which is one of the main noise factors, extremely low noise to reduce RAC noise. This paper describes generating mechanisms of the compressor noise established by analysis using signal processing and computer aided engineering. In addition, concrete countermeasures are presented for the noise reduction of the two-cylinder rotary compressor. In conclusion, Countermeasures for resonance in cavities were achieved by reducing 630Hz∼1KHz levels and the effect of muffler in the chamber contributed to the reduction of 3KHz∼6KHz levels.

  8. Development of Axial Compressor Heat-Extraction Capability for Thermal Management Applications Project (United States)

    National Aeronautics and Space Administration — ATA Engineering, Inc. (ATA) proposes a small business innovation research (SBIR) program for a novel compressor heat-extraction development program in response to...

  9. Modelling and Quasilinear Control of Compressor Surge and Rotating Stall Vibrations

    Directory of Open Access Journals (Sweden)

    Ranjan Vepa


    Full Text Available An unsteady nonlinear and extended version of the Moore-Greitzer model is developed to facilitate the synthesis of a quasilinear stall vibration controller. The controller is synthesised in two steps. The first step defines the equilibrium point and ensures that the desired equilibrium point is stable. In the second step, the margin of stability at the equilibrium point is tuned or increased by an appropriate feedback of change in the mass flow rate about the steady mass flow rate at the compressor exit. The relatively simple and systematic non-linear modelling and linear controller synthesis approach adopted in this paper clearly highlights the main features on the controller that is capable of inhibiting compressor surge and rotating stall vibrations. Moreover, the method can be adopted for any axial compressor provided its steady-state compressor and throttle maps are known.

  10. Low speed axial compressor stall margin improvement by unsteady plasma actuation (United States)

    Li, Gang; Xu, Yanji; Yang, Lingyuan; Du, Wei; Zhu, Junqiang; Nie, Chaoqun


    This research investigates the use of single dielectric barrier discharge (SDBD) actuators for energizing the tip leakage flow to suppress rotating stall inception and extend the stable operating range of a low speed axial compressor with a single rotor. The jet induced by the plasma actuator adds momentum to the flow in the tip region and has a significant impact on the tip-gap flow. Experiments are carried out on a low speed axial compressor with a single rotor. The static pressure is measured at both the rotor inlet and outlet. The flow coefficient and pressure rise coefficient are calculated. Then the characteristic line is acquired to show the overall performance of the compressor. With unsteady plasma actuation of 18kV and 60W the compressor stability range improvement is realized at rotor speed of 1500 r/min — 2400 r/min.

  11. Control of Surge in Centrifugal Compressors by Active Magnetic Bearings Theory and Implementation

    CERN Document Server

    Yoon, Se Young; Allaire, Paul E


    Control of Surge in Centrifugal Compressors by Active Magnetic Bearings sets out the fundamentals of integrating the active magnetic bearing (AMB) rotor suspension technology in compressor systems, and describes how this relatively new bearing technology can be employed in the active control of compressor surge. The authors provide a self-contained and comprehensive review of rotordynamics and the fundamentals of the AMB technology. The active stabilization of compressor surge employing AMBs in a machine is fully explored, from the modeling of the instability and the design of feedback controllers, to the implementation and experimental testing of the control algorithms in a specially-constructed, industrial-size centrifugal compression system. The results of these tests demonstrate the great potential of the new surge control method developed in this text. This book will be useful for engineers in industries that involve turbocompressors and magnetic bearings, as well as for researchers and graduate students...

  12. Rotor clearance design and evaluation for an oil injected twin screw compressor (United States)

    Buckney, D.; Kovacevic, A.; Stosic, N.


    Designing twin screw compressors to safely operate at higher than normal temperatures poses a challenge as the compressor must accommodate larger peak thermal distortions while ideally maintaining efficiency at nominal operating conditions. This paper will present a case study of an oil injected compressor tested at elevated discharge temperatures with original and revised clearances. The local thermal distortions occurring within the compressor during operation were estimated using a procedure developed by the authors - thermodynamic results from a chamber model were used to approximate component temperature distributions that are then used to predict possible thermal distortions and the resulting affect on clearance gaps. The original and revised clearance designs are evaluated and performance penalties incurred due to the modifications are discussed.

  13. An experimental and numerical study on dynamic characteristic of linear compressor in refrigeration system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun; Roh, Chul-gi; Kim, Jong-kwon; Shin, Jong-min [Digital Appliance Company Laboratory, LG Electronics 391-2, Ga Eum Jeong-Dong, Changwon Gyeong Nam 641-711 (Korea); Hwang, Yujin; Lee, Jae-keun [School of Mechanical Engineering, Pusan National University, San 30, Changjeon-Dong, Keumjeong-Ku, Pusan 609-735 (Korea)


    This paper presents experimental and numerical results of the dynamic characteristic and COP of a linear compressor in a refrigeration system using R600 refrigerant. The numerical analysis consists of a model and a simulation that includes the linear compressor. In this study, the dynamic characteristic of the natural frequency of the linear compressor is validated by comparing the simulation results with the experimental results. To investigate the effect of system resonance on the performance of linear compressor, COP is evaluated under evaporator pressure in the range of 48.3-63.2 kPa abs, and condenser pressure in the range of 439.0-573.3 kPa abs. Based on the results, the system resonance at the TDC was varied within a range of 3% under the test conditions. COP and its sensitivity were found to vary within 3% according to the operating frequency of the system ranging from 48.5 to 51.5 Hz. (author)

  14. Study on the Effects of End-bend Cantilevered Stator in a 2-stage Axial Compressor

    Institute of Scientific and Technical Information of China (English)

    Songtao WANG; Xin DU; Zhongqi WANG


    Leading edge recambering is applied to the cantilevered stator vanes in a 2-stage compressor in this paper. Dif-ferent curving effects are produced when the end-bend stator vanes are stacked in different ways. Stacking on the leading edge induces a positive curving effect near the casing.When it is stacked on the centre of gravity, a nega-tive curving effect takes place. The numerical investigation shows that the flow field is redistributed when the end-bend stators with leading edge stacking are applied. The variations in the stage matching for the mainstream and near the hub have an impact on the performance of the 2-stage compressor. The isentropic efficiency and the total pressure ratio of the compressor are increased near the design condition. The compressor total pressure ratio is decreased near choke and near stall. The maximum flow rate is reduced and the stall margin is decreased.

  15. Preliminary Design and Investigation of Integrated Compressor with Composite Material Wheel (United States)

    Wang, Jifeng; Müller, Norbert


    An integrated water vapor compressor with composite material wheel is developed and strength analysis using FEM is presented. The design of wound composite material allows for integrating all rotating parts of the drive that may simply reduce to only the rotor of the electrical motor, since no drive shaft is required anymore. This design can reduce the number of parts and mass, which is convenient for engineers to maintain the compressor. The electrical motors are brushless DC motors operating through a frequency drive and apply a torque on the wheels through the materials bonded in the wheel shrouds. This system allows a large amount of compression to be produced in a multi-stage compression setup. To determine the stress and vibration characteristics of this integrated compressor, numerical analysis is carried out using FEM. The simulation result shows that the integrated compressor with composite material wheel can be used in a chiller system where water as a refrigerant.

  16. Numerical Investigation of the Unsteady Flow in a Transonic Compressor with Curved Rotors

    Institute of Scientific and Technical Information of China (English)

    Mao Mingming; Song Yanping; Wang Zhongqi


    The unsteady 3D flow fields in a single-stage transonic compressor under designed conditions are simulated numerically to inves- tigate the effects of the curved rotors on the stage performance and the aerodynamic interaction between the blade rows. The results show that, compared to the compressor with un-curved rotors, the compressor under scrutiny acquires remarkable increases in efficiency with significantly reduced amplitudes of the time-dependent fluctuation. The amplitude of the pressure fluctuation around the stator leading edge decreases at both endwalls, but increases at the mid-span in the curved rotors. The pressure fluctuation near the stator lead- ing edge, therefore, becomes more uniform in the radial direction of this compressor. Except for the leading edge area, the pressure fluc- tuation amplitude declines remarkably in the tip region of stator surface downstream of the curved rotor, but hardly changes in the mid- dle and at the hub.

  17. Conceptual Design of a Two Spool Compressor for the NASA Large Civil Tilt Rotor Engine (United States)

    Veres, Joseph P.; Thurman, Douglas R.


    This paper focuses on the conceptual design of a two spool compressor for the NASA Large Civil Tilt Rotor engine, which has a design-point pressure ratio goal of 30:1 and an inlet weight flow of 30.0 lbm/sec. The compressor notional design requirements of pressure ratio and low-pressure compressor (LPC) and high pressure ratio compressor (HPC) work split were based on a previous engine system study to meet the mission requirements of the NASA Subsonic Rotary Wing Projects Large Civil Tilt Rotor vehicle concept. Three mean line compressor design and flow analysis codes were utilized for the conceptual design of a two-spool compressor configuration. This study assesses the technical challenges of design for various compressor configuration options to meet the given engine cycle results. In the process of sizing, the technical challenges of the compressor became apparent as the aerodynamics were taken into consideration. Mechanical constraints were considered in the study such as maximum rotor tip speeds and conceptual sizing of rotor disks and shafts. The rotor clearance-to-span ratio in the last stage of the LPC is 1.5% and in the last stage of the HPC is 2.8%. Four different configurations to meet the HPC requirements were studied, ranging from a single stage centrifugal, two axi-centrifugals, and all axial stages. Challenges of the HPC design include the high temperature (1,560deg R) at the exit which could limit the maximum allowable peripheral tip speed for centrifugals, and is dependent on material selection. The mean line design also resulted in the definition of the flow path geometry of the axial and centrifugal compressor stages, rotor and stator vane angles, velocity components, and flow conditions at the leading and trailing edges of each blade row at the hub, mean and tip. A mean line compressor analysis code was used to estimate the compressor performance maps at off-design speeds and to determine the required variable geometry reset schedules of the

  18. Study of casing treatment stall margin improvement phenomena. [for compressor rotor blade tips compressor blades rotating stalls (United States)

    Prince, D. C., Jr.; Wisler, D. C.; Hilvers, D. E.


    The results of a program of experimental and analytical research in casing treatments over axial compressor rotor blade tips are presented. Circumferential groove, axial-skewed slot, and blade angle slot treatments were tested. These yielded, for reduction in stalling flow and loss in peak efficiency, 5.8% and 0 points, 15.3% and 2.0 points, and 15.0% and 1.2 points, respectively. These values are consistent with other experience. The favorable stalling flow situations correlated well with observations of higher-then-normal surface pressures on the rotor blade pressure surfaces in the tip region, and with increased maximum diffusions on the suction surfaces. Annular wall pressure gradients, especially in the 50-75% chord region, are also increased and blade surface pressure loadings are shifted toward the trailing edge for treated configurations. Rotor blade wakes may be somewhat thinner in the presence of good treatments, particularly under operating conditions close to the baseline stall.

  19. The effect of variable stator on performance of a highly loaded tandem axial flow compressor stage (United States)

    Eshraghi, Hamzeh; Boroomand, Masoud; Tousi, Abolghasem M.; Fallah, Mohammad Toude; Mohammadi, Ali


    Increasing the aerodynamic load on compressor blades helps to obtain a higher pressure ratio in lower rotational speeds. Considering the high aerodynamic load effects and structural concerns in the design process, it is possible to obtain higher pressure ratios compared to conventional compressors. However, it must be noted that imposing higher aerodynamic loads results in higher loss coefficients and deteriorates the overall performance. To avoid the loss increase, the boundary layer quality must be studied carefully over the blade suction surface. Employment of advanced shaped airfoils (like CDAs), slotted blades or other boundary layer control methods has helped the designers to use higher aerodynamic loads on compressor blades. Tandem cascade is a passive boundary layer control method, which is based on using the flow momentum to control the boundary layer on the suction surface and also to avoid the probable separation caused by higher aerodynamic loads. In fact, the front pressure side flow momentum helps to compensate the positive pressure gradient over the aft blade's suction side. Also, in comparison to the single blade stators, tandem variable stators have more degrees of freedom, and this issue increases the possibility of finding enhanced conditions in the compressor off-design performance. In the current study, a 3D design procedure for an axial flow tandem compressor stage has been applied to design a highly loaded stage. Following, this design is numerically investigated using a CFD code and the stage characteristic map is reported. Also, the effect of various stator stagger angles on the compressor performance and especially on the compressor surge margin has been discussed. To validate the CFD method, another known compressor stage is presented and its performance is numerically investigated and the results are compared with available experimental results.

  20. The Effect of Variable Stator on Performance of a Highly Loaded Tandem Axial Flow Compressor Stage

    Institute of Scientific and Technical Information of China (English)

    Hamzeh Eshraghi; Masoud Boroomand; Abolghasem M.Tousi; Mohammad Toude Fallah; Ali Mohammadi


    Increasing the aerodynamic load on compressor blades helps to obtain a higher pressure ratio in lower rotational speeds.Considering the high aerodynamic load effects and structural concerns in the design process,it is possible to obtain higher pressure ratios compared to conventional compressors.However,it must be noted that imposing higher aerodynamic loads results in higher loss coefficients and deteriorates the overall performance.To avoid the loss increase,the boundary layer quality must be studied carefully over the blade suction surface.Employment of advanced shaped airfoils (like CDAs),slotted blades or other boundary layer control methods has helped the designers to use higher aerodynamic loads on compressor blades.Tandem cascade is a passive boundary layer control method,which is based on using the flow momentum to control the boundary layer on the suction surface and also to avoid the probable separation caused by higher aerodynamic loads.In fact,the front pressure side flow momentum helps to compensate the positive pressure gradient over the aft blade's suction side.Also,in comparison to the single blade stators,tandem variable stators have more degrees of freedom,and this issue increases the possibility of finding enhanced conditions in the compressor off-design performance.In the current study,a 3D design procedure for an axial flow tandem compressor stage has been applied to design a highly loaded stage.Following,this design is numerically investigated using a CFD code and the stage characteristic map is reported.Also,the effect of various stator stagger angles on the compressor performance and especially on the compressor surge margin has been discussed.To validate the CFD method,another known compressor stage is presented and its performance is numerically investigated and the results are compared with available experimental results.

  1. Solution to the problem of improving reliable operation of the compressor equipment

    Energy Technology Data Exchange (ETDEWEB)

    Kamaleyev, Z.M.


    Questions are examined of improving the efficiency of using compressor equipment: decrease in material and labor outlays for its maintenance, improvement in the quality of repair, increase in the interrepair periods. Organizational forms and technical devices are examined on whose basis in the association ''Sibneftegazpererabotka'' a system is improved for preventive maintenance and improvement in reliability and durability of the compressor operation.

  2. Influence of the superheat associated to a semihermetic compressor of a transcritical CO2 refrigeration plant


    Sánchez, D.; Torrella, E.; Cabello,R; Llopis, R.


    Abstract This work evaluates, from an energetic point of view, the effects of the superheat caused in the refrigerant by the electric motor cooling (SHSC) in a semihermetic compressor installed in an experimental refrigerating plant, which operates with CO2 as the working fluid in transcritical conditions. The analysis is based on 84 experimental tests which cover a wide range of operating conditions of the plant: three evaporating levels (0, -10, -17 ?C) at four compressor speeds ...

  3. Pack of Applied Programs for Complex Analysis of Thermo-Compressors

    Directory of Open Access Journals (Sweden)

    S. V. Zditovetskaya


    Full Text Available The paper proposes a pack of applied programs intended for conjugate calculation of cycle parameters with heat exchangers of thermo-compressor loop and a calculation of irreversible losses in the loop binding including non-stationary operational  mode is added to the pack.The paper contains investigations of thermo-compressor operation in the system of forced and exhaust ventilation for reduction of heat consumption by a heater in the cold season of the year

  4. Development of a dry linear compressor for GM and pulse tube cryocoolers (United States)

    Hoehne, J.


    Pressure Wave Systems GmbH has developed a dry compressor for GM and pulse tube cryocoolers. The concept is based on hydraulically driven metal bellows in which the Helium working gas is compressed. The system is operated in the region of 1 kW of electrical input power and has been successfully tested with a SHI RDK-101D GM cryocooler cold head. Set-up, performance and reliability of the compressor system will be discussed.

  5. Development of a dry linear compressor for GM and pulse tube cryocoolers

    CERN Document Server

    Höhne, Jens


    Pressure Wave Systems GmbH has developed a dry compressor for GM and pulse tube cryocoolers. The concept is based on hydraulically driven metal bellows in which the Helium working gas is compressed. The system is operated in the region of 1 kW of electrical input power and has been successfully tested with a SHI RDK-101D GM cryocooler cold head. Set-up, performance and reliability of the compressor system will be discussed.



    Лавренченко, Г. К.; Швец, С. Г.


    Increase of efficiency of compressor refrigerating machines sets out an actual problem. Features of the new refrigerating machine intended for manufacture of cold on two temperature levels are considered. Limiting characteristics of two-temperature compressor-ejector refrigerating machine (CERM) are analysed. Energy of expansion in it of the refrigerant gas leaving the high-temperature evaporator is used for the compression of steam leaving from low-temperature evaporator. The circuit and cyc...

  7. Process and apparatus for recovery from rotating stall in axial flow fans and compressors



    Active recovery from a rotating stall operating condition in an axial flow compression system is accomplished by altering the temperature and/or density of the working fluid flowing in the inlet of the compression system once rotating stall is detected. A burner is used to increase the compressor inlet flow temperature and concomitantly reduce the inlet flow density. Alternatively, a low density gas such as helium is injected into the compressor inlet. The ingestion of high temperature gases ...

  8. Chemical Compatibility of High-Performance Engineering Thermoplastics in Compressor Environments


    Pai-Paranjape, Vandita


    The compressor industry faces a difficult design environment for achieving performance improvement, reduced cost, and lower environmental footprint. In order to address some of these challenges, thermoplastics can be considered as a replacement for metal in some compressor parts. Thermoplastics have been found to be suitable for steel replacement in structural parts for automotive and brass replacement in water-handling applications such as meters. As such, we believe certain high-performance...

  9. Experimental study of a pulse tube cold head driven by a low frequency thermal compressor


    Zhao, Y.; Dai, W.; Vanapalli, S.; Wang, X.; Chen, Y; Luo, E.


    Cryocoolers operating at liquid helium temperature span a number of application domains, such as cooling of superconducting magnets, SQUID devices etc. GM type cryocoolers are widely used at liquid helium temperature but with shortcomings of using an oil-lubricated compressor that require regular maintenance and rotary valves that reduces the efficiency of the cryocooler. We are developing an alternative system that makes use of a Vuilleumier type thermal compressor. The system consists of a ...

  10. Using Magnetic Bearing Orbit Information to Maximize Centrifugal Compressor Efficiency at Off-Design Conditions



    Active magnetic bearings used on oil-free centrifugal refrigeration compressors have lower stiffness than conventional oil-lubricated journal or rolling element bearings. The lower stiffness of these bearings makes them sensitive to internal flow instabilities that are precursors of rotating stall or compressor surge. At operating conditions far away from surge the internal flow is very stable and the magnetic bearings keep the shaft centered, resulting in a minimal bearing orbit. The interna...

  11. Electric compressor with high-speed brushless DC motor; E-Kompressor mit buerstenlosem Gleichstrommotor

    Energy Technology Data Exchange (ETDEWEB)

    Biwersi, Stephan; Tavernier, Stephan; Equoy, Samuel [Moving Magnet Technologies (MMT), Besancon (France)


    Moving Magnet Technologies (MMT) from Besancon in France has developed a highly efficient brushless DC motor that is especially suitable for use in electrically supported compressors. It helps to further minimise so-called turbo lag in supercharged internal combustion engines. The following report presents technical details of the electric motor and practical results in combination with an electrically driven compressor. MMT was supported by Swissauto in designing the supercharging system.

  12. Numerical Simulation of Sand Erosion Phenomena in Rotor/Stator Interaction of Compressor

    Institute of Scientific and Technical Information of China (English)

    Masaya Suzuki; Kazuaki Inaba; Makoto Yamamoto


    Sand erosion is a phenomenon where solid particles impinging to a wall cause serious mechanical damages to the wall surface. This phenomenon is a typical gas-particle two-phase turbulent flow and a multi-physics problem where the flow field, particle trajectory and wall deformation interact with each other. On the other hand, aircraft engines operating in a particulate environment are subjected to the performance and lifetime deterioration due to sand erosion. Especially, the compressor of the aircraft engines is severely damaged. The flow fields of the compressor have strongly three dimensional and unsteady natures. In order to estimate the deterioration due to sand erosion, the sand erosion simulation for a compressor is required under the consideration of the rotor-stator interaction. In the present study, we apply our three dimensional sand erosion prediction code to a single stage axial flow compressor. We numerically investigate the change of the flow field, the particle trajectories, and the eroded wall shape in the compressor, to clarify the effects of sand erosion in the compressor.

  13. Keeping Your Compressor Healthy: Developing the Right Lubricant Formulation is the Key (United States)

    Karnaz, Joseph A.; Kultgen, Derek W.


    Selecting the correct compressor lubricant is crucial to the duration of the compressor and the refrigerant systems’ useful life. However, developing an optimized lubricant for a refrigeration system requires a multitude of screenings and tests. The compatibility and stability of the lubricant with the refrigerant and compressor components needs to be examined at various accelerated conditions. The lubricant and refrigerant working viscosity must be determined at various refrigerant concentrations, temperatures and pressures as the diluted refrigerant in the lubricant has a significant effect on the viscosity. The correct lubricant formulation needs to be investigated for optimal performance. A compressor lubricant can provide many benefits to a refrigeration system such as bearing durability, sealing, and increased efficiency. Sometimes it is necessary to formulate the lubricant in order to optimize system performance. Specifically, this study investigated anti-wear properties of different oil additives to create a more robust refrigeration system. Many different additives and concentrations were considered and screened. Pending a successful screen test; these different additives’ anti-wear properties were analyzed using bench top tribology tests. To reduce uncertainty and provide more in-situ results the different additives were operated in a refrigerant compressor on a gas-loop testing apparatus. Oil samples were taken periodically during the test duration for analysis. Lastly, upon test completion the compressors were dismantled and the parts were examined to determine the effectiveness of the anti-wear additives.

  14. An Investigation of Surge in a High-Speed Centrifugal Compressor Using Digital PIV (United States)

    Wernet, Mark P.; Bright, Michelle M.; Skoch, Gary J.


    Compressor stall is a catastrophic breakdown of the flow in a compressor, which can lead to a loss of engine power, large pressure transients in the inlet/nacelle and engine flameout. The implementation of active or passive strategies for controlling rotating stall and surge can significantly extend the stable operating range of a compressor without substantially sacrificing performance. It is crucial to identify the dynamic changes occurring in the flow field prior to rotating stall and surge in order to successfully control these events. Generally, pressure transducer measurements are made to capture the transient response of a compressor prior to rotating stall. In this investigation, Digital Particle Imaging Velocimetry (DPIV) is used in conjunction with dynamic pressure transducers to simultaneously capture transient velocity and pressure measurements in the non-stationary flow field during compressor surge. DPIV is an instantaneous, planar measurement technique which is ideally suited for studying transient flow phenomena in high speed turbomachinery and has been used previously to successfully map the stable operating point flow field in the diffuser of a high speed centrifugal compressor. Through the acquisition of both DPIV images and transient pressure data, the time evolution of the unsteady flow during surge is revealed.

  15. 本特利3500在空压机振动检测中的应用%Application of Bentley 3500 Protection System in Compressor Vibration Monitoring System

    Institute of Scientific and Technical Information of China (English)



    针对莱钢60000 m3/h制氧空压机振动检测系统稳定性能不足的问题,提出了利用本特利公司3500保护系统的改造方案,该方案技术成熟、稳定性高、拓展性强,完全符合空压机振动检测系统的要求。介绍了改造后的系统组态及各类模块实现的功能。%To the problem of poor stability of vibration monitoring system for Laiwu Steel 60 000 m3/h air compressor ,a transformation scheme applying Bentley Company 3500 protection system to the compressor vibration monitoring system is put forward .The scheme is of mature technology ,high stability and strong expandability ,fully meeting the requirements of air compressor vibration detection system .This paper introduces the system hardware configuration and the function of each modules .

  16. Modified A{sup ++}-standard refrigerator with 30% reduction of energy consumption. Higher efficiency by compressor modification - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Siegrist, M.; Stahl, S.; Ganz, J.


    This final report for the Swiss Federal Office of Energy (SFOE) takes a look at how a modified refrigerator can be given a higher efficiency by modifying the compressor. The modified refrigerator was fitted with a variable-speed compressor. This compressor could be run at much lower speeds so that it was in operation for up to 90% of the time. It was shown that less electricity was consumed the more the compressor ran. The report discusses the aims of the work and presents details on the standard refrigerator used for the tests. The compressor normally used and the variable-speed compressor used in the test are described. Systems for temperature control and data acquisition during the tests are described. The results obtained are examined and the influence of various factors is discussed.

  17. A thermal model for analysis of hermetic reciprocating compressors under the on-off cycling operating condition (United States)

    Lohn, S. K.; Diniz, M. C.; Deschamps, C. J.


    The on-off cycling operating condition of compressors is very common in low capacity refrigeration systems, being characterized by alternate periods in which the compressor is either operating (on) or idle (off). Thermal interactions between the compressor components affect its performance during the operating period and establish the initial condition for the compressor start up from idle condition. This paper presents a numerical model to predict the temperature field of hermetic reciprocating compressors under on-off cycling conditions. The model adopts a lumped formulation for control volumes formed in the fluid solution domain and the finite volume method to solve heat conduction in the solid components. Some required heat transfer coefficients were experimentally adjusted. Predictions for temperature were compared to measurements and good agreement was observed, especially for the thermal transient during the period in which the compressor is off.

  18. An evaluation of 1D loss model collections for the off-design performance prediction of automotive turbocharger compressors (United States)

    Harley, P.; Spence, S.; Early, J.; Filsinger, D.; Dietrich, M.


    Single-zone modelling is used to assess different collections of impeller 1D loss models. Three collections of loss models have been identified in literature, and the background to each of these collections is discussed. Each collection is evaluated using three modern automotive turbocharger style centrifugal compressors; comparisons of performance for each of the collections are made. An empirical data set taken from standard hot gas stand tests for each turbocharger is used as a baseline for comparison. Compressor range is predicted in this study; impeller diffusion ratio is shown to be a useful method of predicting compressor surge in 1D, and choke is predicted using basic compressible flow theory. The compressor designer can use this as a guide to identify the most compatible collection of losses for turbocharger compressor design applications. The analysis indicates the most appropriate collection for the design of automotive turbocharger centrifugal compressors.

  19. Improvement of Performance Range of Centrifugal Compressors Gas by Surge Line Modification Using Active Controller Based on Fuzzy Logic

    Directory of Open Access Journals (Sweden)

    Pezhman Mohammadi


    Full Text Available In this work, surge of prevention is a critical problem in oil and gas industries, particularly when return gas flow or gas flow reduces in transportation of gas pipelines. This paper is illustrated new results about surge control of centrifugal compressors .surge phenomenon is flow unsteady state in compressors which causes damages seriously in compressor construction. Furthermore, it also demonstrates in comparison with anti surge control ،active surge control expands stability range.Active surge control which based on fuzzy logic،is the main idea that used in this investigation. Using fuzzy controller causes an improvement in compressor's condition and increase performance range of the compressor, in addition to prevention of any instability in compressor. The simulation results is also satisfactory.

  20. Wet Compression Performance of a Transonic Compressor Rotor at its Near Stall Point%失速点上湿压缩对于跨音速压气机转子性能的影响

    Institute of Scientific and Technical Information of China (English)

    杨怀丰; 郑群; 罗铭聪; 孙兰昕; Rakesh Bhargava


    In order to study the effects of wet compression on a transonic compressor, a full 3-D steady numerical simulation was carried out under varying conditions. Different injected water flow rates and droplet diameters were considered. The effect of wet compression on the shock, separated flow, pressure ratio, and efficiency was investigated. Additionally, the effect of wet compression on the tip clearance when the compressor runs in the near-stall and stall situations was emphasized. Analysis of the results shows that the range of stable operation is extended, and that the pressure ratio and inlet air flow rate are also increased at the near-stall point. In addition, it seems that there is an optimum size of the droplet diameter.

  1. VRV系统并联型压缩机油平衡策略研究%Study on the Strategy of Lubricant Balancing between Parallel Compressors in VRV System

    Institute of Scientific and Technical Information of China (English)

    程德威; 姜灿华


    针对直流变频变容量VRV空调系统中并联压缩机间润滑油平衡问题,概述了不同厂家并联型压缩机润滑油平衡策略。并根据不同的压缩机,设计了并联压缩机之间的油平衡系统。%According to the lubricant balancing problem between parallel compressors in DC inverter VRV system,the lubricant balancing strategy for different scroll compressors manufactured by different manufacturers was reviewed,and different lubricant balancing pipelines for VRV air-conditioners.

  2. Performance analysis of liquid air energy storage utilizing LNG cold energy (United States)

    Luyao, Li; Sixian, Wang; Zhang, Deng; Luwei, Yang; Yuan, Zhou; Junjie, Wang


    As the high energy density and can be stored in a long period, the liquid air is regarded as the potential energy storage medium. In the liquid air energy storage (LAES) system, liquid air is produced in the liquefaction processes by using the renewable energy or off-peak energy. The compressor is used to supply and recycle the air in liquefaction processes. In this paper, a LAES model is established, and the impact of compressor on LAES system is analysed theoretically. Liquid air energy storage (LAES) system utilizing LNG cold energy is also described. The results show that the round trip energy efficiency is enhanced and the utilizing has promising application prospect for large scale energy storage.

  3. Design of a Compressor Load Stand Capable of Supplying Two-Phase Refrigerant at Two Intermediate Pressures


    Gu, Rui; Mathison, Margaret M.


    The development of compressors with refrigerant injection ports provides a less complex and less costly alternative to implementing multi-stage compressors with economization. The ports can be used to inject economized refrigerant during the compression process, which provides the desired cooling effect and decreases the work required to compress the gas per unit mass. Experiments have shown that injecting liquid or low quality refrigerant is effective for reducing the compressor exit tempera...

  4. Active control of surge in centrifugal compressors using magnetic thrust bearing actuation (United States)

    Sanadgol, Dorsa

    This research presents a new method for active surge control in centrifugal compressors with unshrouded impellers using a magnetic thrust bearing to modulate the impeller tip clearance. Magnetic bearings offer the potential for active control of flow instabilities. This capability is highly dependent on the sensitivity of the compressor characteristics to blade tip clearance. If the position of the shaft can be actuated with sufficient authority and speed, the induced pressure modulation makes control of surge promising. The active nature of the magnetic bearing system makes the real-time static and dynamic positioning of the rotor and therefore modulation of the impeller tip clearance possible. A theoretical model is first established that describes the sensitivity of the centrifugal compressor characteristic curve to tip clearance variations induced by axial motion of the rotor. Results from simulation of the nonlinear model for a single stage high-speed centrifugal compressor show that using the proposed control method, mass flow and pressure oscillations associated with compressor surge are quickly suppressed with acceptable tip clearance excursions, typically less than 20% of the available clearance. It is shown that it is possible to produce adequate axial excursions in the clearance between the impeller blades and the adjacent stationary shroud using a magnetic thrust bearing with practical levels of drive voltage. This surge control method would allow centrifugal compressors to reliably and safely operate with a wider range than is currently done in the field. The principal advantage of the proposed approach over conventional surge control methods lies in that, in machines already equipped with magnetic bearing, the method can potentially be implemented by simply modifying controller software. This dispenses with the need to introduce additional hardware, permitting adaptation of existing machinery at virtually no cost. In addition, since the controller is

  5. Unit consisting of a rotating cylinder internal combustion engine and a rotating cylinder compressor. Maschinenaggregat bestehend aus einer Rotationskolbenbrennkraftmaschine und einem Rotationskolbenkompressor

    Energy Technology Data Exchange (ETDEWEB)

    Nuber, R.; Schubert, W.; Sohler, W.; Sutter, F.


    This is a unit consisting of a rotating cylinder internal combustion engine of trochoid construction to drive the cooling compresor of the same type and an electricity generator via belt drives, which is situated compactly in a vibration-damped pipe frame in a metal housing, where the internal combustion engine drives a fan via a Cardan joint and a drive shaft movable longitudinally. The unit is connected to an air conditioning plant which can be cooled via a cooling system with a compressor whose condenser is in the air flow of the fan, or can be heated by the waste heat of the internal combustion engine. In the first case, the internal combustion engine is cooled via a cooler in the flow of the fan. The unit is intended to be portable for use in disasters or for military purposes.

  6. 77 FR 2970 - Notice of Intent To Prepare an Environmental Assessment for the Proposed Elba BOG Compressor... (United States)


    ... horsepower electric-motor driven reciprocating gas compressor; flow metering modifications; underground... associated with fabrication, parking, and staging areas, which have been previously disturbed....

  7. Modeling of an Oil-Free Carbon Dioxide Compressor Using Sanderson-Rocker Arm Motion (S-RAM) Mechanism (United States)

    Yang, Bin; Kurtulus, Orkan; Groll, Eckhard A.


    A simulation model to predict the performance of a prototype CO2 compressor is presented. This prototype compressor employs the Sanderson-Rocker Arm Motion (S-RAM) mechanism, which converts the rotary motion of the shaft into a linear reciprocating motion of the cylinders. The piston stroke can be variable by changing the incline angle between the connecting rod and compressor main shaft centerline. The compressor model is mainly composed of two main sub-models simulating the kinematics of the drive mechanism and the compression process. A valve sub-model is included in the compression process model.

  8. 空压机能量回收技术应用研究%Compressor technology of energy recovery

    Institute of Scientific and Technical Information of China (English)



    Compressor is one of the main auxiliary equipment in modem factories, and is a large power consumption. However, only 30% power is utilized. Value of the energy is wasted and caused global warming pollution. Today, energy conservation, low-carbon cycle of the economy has gradually become the focus of attention. Analysis of the air compressor, we discovered that power changed into heat and was taken away by the cooling oil and compression air. Now it is the traditional way using natural wind plus exhaust fan for cooling, and the cooling the air was discharged into the atmosphere, resulting in substantial waste of energy, while the cooling effect of the equipment is poor. Through the new process implemented by the wind use cold water, it can achieve 75% of heat recycling.%空压机是工业领域必不可少的主要辅助生产设备之一,是电能;肖耗“大户”,但真正由电能转换成压缩空气的能量不足30%,期间大量的电能转换成“无价值”的热能被浪费,对环境造成严重的“温室效应”污染。然而节能减排、低碳循环经济已经逐渐成为人们关注的焦点。分析空压机原理,发现大量电能转化成热能由冷却油及压缩空气带走,目前传统方式用的是自然风加抽风机进行冷却,冷却后的风排入大气,造成能量的大量浪费,同时对设备的冷却效果并不佳,利用新型工艺技术改进,由风冷冷改用水冷,实现75%以上的热能回收利用。

  9. Compressor Calorimeter Test of R-404A Alternatives ARM-31a, D2Y-65, L-40, and R32 + R-134a Mixture using a Scroll Compressor

    Energy Technology Data Exchange (ETDEWEB)

    Shrestha, Som S [ORNL; Sharma, Vishaldeep [ORNL; Abdelaziz, Omar [ORNL


    As a contribution to the AHRI Low-GWP Alternative Refrigerants Evaluation Program (AREP), this study compares the performance of four lower-GWP alternative refrigerants, ARM-31a, D2Y-65, L-40, and R-32 + R-134a mixture, to that of refrigerant R-404A (baseline) in a scroll compressor designed for medium temperature refrigeration applications. These comparisons were carried out via compressor calorimeter tests performed on a compressor designed for refrigerant R-404A and having a nominal rated capacity of 23,500 Btu/hr. Tests were conducted over a suction dew point temperature range of -10 F to 35 F in 5 F increments and a discharge dew point temperature range of 70 F to 140 F in 10 F increments. All the tests were performed with 20 F superheat, 40 F superheat, and 65 F suction temperature. A liquid subcooling level of 10 F to 15 F was maintained for all the test conditions. However, the cooling capacities reported in this study are normalized for 0 F subcooling. The tests showed that the compressor energy efficiency ratio (EER) and cooling capacity with all four alternative refrigerants tested are higher at higher saturation suction and saturation discharge temperature and lower at lower saturation suction and saturation discharge temperature, compared to that of R-404A. Discharge temperatures of all the alternative refrigerants were higher than that of R-404A at all test conditions.

  10. High Efficiency Room Air Conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, Pradeep [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)


    This project was undertaken as a CRADA project between UT-Battelle and Geberal Electric Company and was funded by Department of Energy to design and develop of a high efficiency room air conditioner. A number of novel elements were investigated to improve the energy efficiency of a state-of-the-art WAC with base capacity of 10,000 BTU/h. One of the major modifications was made by downgrading its capacity from 10,000 BTU/hr to 8,000 BTU/hr by replacing the original compressor with a lower capacity (8,000 BTU/hr) but high efficiency compressor having an EER of 9.7 as compared with 9.3 of the original compressor. However, all heat exchangers from the original unit were retained to provide higher EER. The other subsequent major modifications included- (i) the AC fan motor was replaced by a brushless high efficiency ECM motor along with its fan housing, (ii) the capillary tube was replaced with a needle valve to better control the refrigerant flow and refrigerant set points, and (iii) the unit was tested with a drop-in environmentally friendly binary mixture of R32 (90% molar concentration)/R125 (10% molar concentration). The WAC was tested in the environmental chambers at ORNL as per the design rating conditions of AHAM/ASHRAE (Outdoor- 95F and 40%RH, Indoor- 80F, 51.5%RH). All these modifications resulted in enhancing the EER of the WAC by up to 25%.

  11. NNIC—neural network image compressor for satellite positioning system (United States)

    Danchenko, Pavel; Lifshits, Feodor; Orion, Itzhak; Koren, Sion; Solomon, Alan D.; Mark, Shlomo


    We have developed an algorithm, based on novel techniques of data compression and neural networks for the optimal positioning of a satellite. The algorithm is described in detail, and examples of its application are given. The heart of this algorithm is the program NNIC—neural network image compressor. This program was developed for compression color and grayscale images with artificial neural networks (ANNs). NNIC applies three different methods for compression. Two of them are based on neural networks architectures—multilayer perceptron and kohonen network. The third is based on a widely used method of discrete cosine transform, the basis for the JPEG standard. The program also serves as a tool for determining numerical and visual quality parameters of compression and comparison between different methods. A number of advantages and disadvantages of the compression using ANNs were discovered in the course of the present research, some of them presented in this report. The thrust of the report is the discussion of ANNs implementation problems for modern platforms, such as a satellite positioning system that include intensive image flowing and processing.

  12. Optimal Design of a Centrifugal Compressor Impeller Using Evolutionary Algorithms

    Directory of Open Access Journals (Sweden)

    Soo-Yong Cho


    Full Text Available An optimization study was conducted on a centrifugal compressor. Eight design variables were chosen from the control points for the Bezier curves which widely influenced the geometric variation; four design variables were selected to optimize the flow passage between the hub and the shroud, and other four design variables were used to improve the performance of the impeller blade. As an optimization algorithm, an artificial neural network (ANN was adopted. Initially, the design of experiments was applied to set up the initial data space of the ANN, which was improved during the optimization process using a genetic algorithm. If a result of the ANN reached a higher level, that result was re-calculated by computational fluid dynamics (CFD and was applied to develop a new ANN. The prediction difference between the ANN and CFD was consequently less than 1% after the 6th generation. Using this optimization technique, the computational time for the optimization was greatly reduced and the accuracy of the optimization algorithm was increased. The efficiency was improved by 1.4% without losing the pressure ratio, and Pareto-optimal solutions of the efficiency versus the pressure ratio were obtained through the 21st generation.

  13. Performance of Lempel-Ziv compressors with deferred innovation (United States)

    Cohn, Martin


    The noiseless data-compression algorithms introduced by Lempel and Ziv (LZ) parse an input data string into successive substrings each consisting of two parts: The citation, which is the longest prefix that has appeared earlier in the input, and the innovation, which is the symbol immediately following the citation. In extremal versions of the LZ algorithm the citation may have begun anywhere in the input; in incremental versions it must have begun at a previous parse position. Originally the citation and the innovation were encoded, either individually or jointly, into an output word to be transmitted or stored. Subsequently, it was speculated that the cost of this encoding may be excessively high because the innovation contributes roughly 1g(A) bits, where A is the size of the input alphabet, regardless of the compressibility of the source. To remedy this excess, it was suggested to store the parsed substring as usual, but encoding for output only the citation, leaving the innovation to be encoded as the first symbol of the next substring. Being thus included in the next substring, the innovation can participate in whatever compression that substring enjoys. This strategy is called deferred innovation. It is exemplified in the algorithm described by Welch and implemented in the C program compress that has widely displaced adaptive Huffman coding (compact) as a UNIX system utility. The excessive expansion is explained, an implicit warning is given against using the deferred innovation compressors on nearly incompressible data.

  14. An Efficient Image Compressor for Charge Coupled Devices Camera

    Directory of Open Access Journals (Sweden)

    Jin Li


    Full Text Available Recently, the discrete wavelet transforms- (DWT- based compressor, such as JPEG2000 and CCSDS-IDC, is widely seen as the state of the art compression scheme for charge coupled devices (CCD camera. However, CCD images project on the DWT basis to produce a large number of large amplitude high-frequency coefficients because these images have a large number of complex texture and contour information, which are disadvantage for the later coding. In this paper, we proposed a low-complexity posttransform coupled with compressing sensing (PT-CS compression approach for remote sensing image. First, the DWT is applied to the remote sensing image. Then, a pair base posttransform is applied to the DWT coefficients. The pair base are DCT base and Hadamard base, which can be used on the high and low bit-rate, respectively. The best posttransform is selected by the lp-norm-based approach. The posttransform is considered as the sparse representation stage of CS. The posttransform coefficients are resampled by sensing measurement matrix. Experimental results on on-board CCD camera images show that the proposed approach significantly outperforms the CCSDS-IDC-based coder, and its performance is comparable to that of the JPEG2000 at low bit rate and it does not have the high excessive implementation complexity of JPEG2000.

  15. Three-dimensional flows in a transonic compressor rotor (United States)

    Reid, Lonnie; Celestina, Mark L.; Dewitt, Kenneth; Keith, Theo


    This study involves an experimental and numerical investigation of the three-dimensional flows in a transonic compressor rotor. A variety of data which could be used, in a complementary fashion, to validate/calibrate the computational fluid dynamics turbomachinery code and improve understanding of the flow physics, were acquired. Detailed radial survey data which consisted of total pressure, total temperature, static pressure and flow angle were obtained at stations upstream and downstream of the rotor blade. Detailed velocity and turbulence profiles were obtained upstream of the rotor and used as the upstream boundary conditions for the numerical analysis. Calibrated flush-mounted hot film probes were used to measure wall shear stress on the hub and casing walls upstream of the rotor. The blade-to-blade shear-stress angle distributions were obtained at two axial locations on the rotor casing, using flush-mounted hot film probes. A numerical analysis conducted using a three-dimensional Navier-Stokes code was compared with the experimental results.

  16. Simulation technology for refrigeration and air conditioning appliances

    Institute of Scientific and Technical Information of China (English)

    DING Guoliang


    Simulation technology has been widely used for performance prediction and optimal design of refrigeration and air conditioning appliances. A brief history of simulation technology for refrigeration and air conditioning appliances is reviewed. The models for evaporator, condenser, compressor, capillary tube and thermal insulation layer are summarized, and a fast calculation method for thermodynamic properties of refrigerant is introduced in this paper. The model-based intelligent simulation technology and the simulation technology based on graph theory are also illustrated. Finally, an updated trend of simulation technology development for refrigeration and air conditioning appliances is discussed.

  17. Possibilities for the filtration of inlet air for gas turbines

    Energy Technology Data Exchange (ETDEWEB)

    Sievert, J.; Reinhardt, H.


    Gas turbines require large quantities of air, which are sucked in from the atmosphere. Depending on the weather conditions and the location of the gas turbine the ambient air contains impurities which may lead to damage to or contamination of the blading of the compressors and turbines. In consequence this causes a reduction in output or efficiency. In principle there are several possibilities for the filtration of air sucked in for gas turbines of which the technically relevant ones at the present time are described.

  18. High-temperature heat pump, phase 1: using a compressor with a vapour injection port; Pompe a chaleur haute temperature, phase 1: solution avec compresseur a injection vapeur

    Energy Technology Data Exchange (ETDEWEB)

    Brand, F.; Zehnder, M.; Favrat, D.


    The High Temperature Heat Pump project aims at developing an air-to-water heat pump that can replace a gas or fuel boiler in a house. To reach this goal, the heat pump must be able to produce domestic hot water at high temperature to allow the house's network to properly operate. A first objective is to produce hot water at 65 {sup o}C. A first prototype has been developed, starting from one of the most efficient heat pumps on the market. The pump was modified so as to function with a prototype compressor equipped with a vapour injection port. A series of tests highlighted not only the performance improvements due to the vapour injection but also the increase of the operation range of the heat pump and the optimal operating range of the injection. In terms of the coefficient of performance (COP) the gain increases with the reduction in temperature of the intake air; the improvement is on an average 13% in the operating range tested. With an ambient-air temperature of -12 {sup o}C it is possible to obtain hot water at 65 {sup o}C, whereas without injection the intake air must be at least 2 {sup o}C to reach the same water temperature. An average gain of 25% is obtained by injection for hot power. For measurement with de-icing, point A2/W50 with an optimal injection makes it possible to obtain a COP of 2.7 with a hot power of 9.4 kW. The defrosting cycle analysis makes possible to expect an improvement of these performances by optimisation and adjustment of the heat pump parameters. A thermostatic valve, whose probe is placed at the compressor output, controls the injection. It makes it possible to obtain an optimal operation for flows injected. Measurement results support a theoretical analysis of the whole installation and in particular of the compressor with injection port. This analysis will be used within the framework of a more detailed thermo economic heat pump study. (author)

  19. Heat pump air conditioning system for pure electric vehicle at ultra-low temperature

    Directory of Open Access Journals (Sweden)

    Li Hai-Jun


    Full Text Available When the ordinary heat pump air conditioning system of a pure electric vehicle runs at ultra-low temperature, the discharge temperature of compressor will be too high and the heating capacity of the system will decay seriously, it will lead to inactivity of the heating system. In order to solve this problem, a modification is put forward, and an experiment is also designed. The experimental results show that in the same conditions, this new heating system increases more than 20% of the heating capacity; when the outside environment temperature is negative 20 degrees, the discharge temperature of compressor is below 60 degrees.

  20. Investigation of several important phenomena associated with the development of Knudsen compressors (United States)

    Young, Marcus Paul

    The perceived utility of compact, power efficient sensor systems, coupled with recent advances in micro-electro-mechanical systems (MEMS) fabrication capabilities, have encouraged the construction of micro/meso-scale sensors. Viable micro/meso-scale sensors have been demonstrated; however, in many cases micro/meso-scale vacuum pumps are required to complete the sensor systems. The Knudsen Compressor, a micro/meso-scale gas pump based on thermal transpiration, is one proposed technology for a micro/meso-scale gas roughing pump. There are additional potential far term applications for Knudsen Compressors applied as high-pressure gas sources. Knudsen Compressors have important advantages over other proposed micro/meso-scale gas roughing pumps: no moving parts, no oils or other supplementary fluids, quiet and steady operation, easily scalable, and a range of potential heating activation techniques. The primary focus of this thesis is technological and scientific advancements leading to the development of radiantly driven micro/meso-scale Knudsen Compressors as roughing pumps. Considerations for operating Knudsen Compressors near a practical minimum operating pressure, 10 mTorr, and maximum operating pressure, 10 atm, are discussed. Initial experiments and modeling with glass microsphere beds, one possible low-pressure transpiration membrane, are discussed. Several potentially significant flow phenomena are predicted to appear at high pressures. The Knudsen Compressor Performance Model is updated to include: short tube effects, a generalized aerogel transpiration model, radiant heating capabilities, and outward transpiration membrane cooling effects. The model was also altered to provide time dependent pumping simulations. The Knudsen Compressor Performance Model was used to complete optimization studies and to construct several proposed designs for different applications. Transpiration membrane temperature and steady-state pressure measurements were taken for a variety

  1. Study on seal improvement and rotor thrust control of centrifugal compressor

    Institute of Scientific and Technical Information of China (English)


    Fluid pressure variations due to process fluctuations or balance drum seal degradation can result in rotor thrust increasing that may jeopardize thrust bearing and compressor's reliability. Also, the leakage flow through balance drum seal can seriously affect the efficiency of compressor. A method that can improve both the efficiency and reliability of centrifugal compressor is presented. The method focused on rotor thrust control and balance drum seal upgrading. The low leakage feature of Dry-Gas-Seal(DGS), high reliability of labyrinth, and the feasibility of upgrading existing structure are taken into account at the same time to design a combined labyrinth-dry gas seal system on the balancing drum. Based on the combined seal system, a Fault Self-Recovering(FSR) system for the fault of rotor shaft displacement is introduced to assure the safety and reliability of centrifugal compressor. The modern Computational Fluid Dynamics(CFD) is used to validate this envision. The numerical result and relevant information indicate that the combined sealing system could improve the efficiency of the centrifugal compressor by about 4%.

  2. Pipeline investigation report : natural gas compressor station occurrence : Gazoduc TQM Inc., December 2000

    Energy Technology Data Exchange (ETDEWEB)



    On December 28, 2000, a release of natural gas resulted in an explosion that destroyed the electrical and services building at the Gazoduc TQM East Hereford compressor station, damaging the compressor building. Before the occurrence, the station had been shut down due to a manual initiation of the station's emergency shutdown system. A maintenance person was sent to the station to reinitiate the electric motor-driven compressor unit. The on-site maintenance person was seriously injured. This report presents factual information about the accident, the injuries and the damage to equipment. It also reviews particulars of the pipeline system, the compressor station design, construction and operations. An analysis of the natural gas stream found an unknown product in the compressor station. A history of previous explosions, ruptures, leaks and fires was presented along with quality control programs. Findings as to the causes and contributing factors of the accident were revealed along with findings as to risk and safety actions. tabs., figs.


    Energy Technology Data Exchange (ETDEWEB)

    Robert J. Mckee; Danny M. Deffenbaugh


    This annual progress report describes the second year's technical progress in a three-year program. This report summarizes what is known about internal flows as surge precursors in centrifugal compressors and focuses on accessing factors that affect pre-surge detection. An attempt is made in this analysis to identify and quantify factors concerning compressor design and operations that affect the detection of pre-surge conditions. This progress report presents results from recent laboratory tests conducted during the course of this second year. This project is co-funded by the Gas Machinery Research Council (GMRC) and by Siemens Energy and Automation (Siemens). The most recently available measured pre-surge internal flow data is parameterized to help identify factors that affect the indications that a compressor is approaching surge. Theoretical arguments are applied to access the factors that influence surge precursors and surge initiation in different centrifugal compressors. This work is considered a step in accessing the factors that affect the success or limitations of pre-surge detection in natural gas pipeline compressors.

  4. Effect of blade tip winglet on the performance of a highly loaded transonic compressor rotor

    Institute of Scientific and Technical Information of China (English)

    Han Shaobing; Zhong Jingjun


    The tip leakage flow has an important influence on the performance of transonic com-pressor. Blade tip winglet has been proved to be an effective method to control the tip leakage flow in compressor, while the physical mechanisms of blade tip winglet have been poorly understood. A numerical study for a highly loaded transonic compressor rotor has been conducted to understand the effect of varying the location of blade tip winglet on the performance of the rotor. Two kinds of tip winglet were designed and investigated. The effects of blade tip winglet on the compressor over-all performance, stability and tip flow structure were presented and discussed. It is found that the interaction of the tip winglet with the flow in the tip region is different when the winglet is located at suction-side or pressure-side of the blade tip. Results indicate that the suction-side winglet (SW) is ineffective to improve the performance of compressor rotor. In addition, a significant stall range extension equivalent to 33.74% with a very small penalty in efficiency can be obtained by the pressure-side winglet (PW). An attempt has been made to explain the fundamental mechanisms of blade tip winglet in detail.

  5. Linear Resonance Compressor for Stirling-Type Cryocoolers Activated by Piezoelectric Stack-Type Elements (United States)

    Sobol, S.; Grossman, G.


    A novel type of a PZT- based compressor operating at mechanical resonance, suitable for pneumatically-driven Stirling-type cryocoolers was developed theoretically and built practically during this research. A resonance operation at relatively low frequency was achieved by incorporating the piezo ceramics into the moving part, and by reducing the effective piezo stiffness using hydraulic amplification. The detailed concept, analytical model and the test results of the preliminary prototype were reported earlier and presented at ICC17 [2]. A fine agreement between the simulations and experiments spurred development of the current actual compressor designed to drive a miniature Pulse Tube cryocooler, particularly our MTSa model, which operates at 103 Hz and requires an average PV power of 11 W, filling pressure of 40 Bar and a pressure ratio of 1.3. The paper concentrates on design aspects and optimization of the governing parameters. The small stroke to diameter ratio (about 1:10) allows for the use of a composite diaphragm instead of a clearance-seal piston. The motivation is to create an adequate separation between the working fluid and the buffer gas of the compressor, thus preventing possible contamination in the cryocooler. Providing efficiency and power density similar to those of conventional linear compressors, the piezo compressor may serve as a good alternative for cryogenic applications requiring extreme reliability and absence of magnetic field interference.

  6. Numerical and Experimental Investigation of Pressure Losses at Suction of a Twin Screw Compressor (United States)

    Arjeneh, M.; Kovacevic, A.; Rane, S.; Manolis, M.; Stosic, N.


    Rotary twin screw machines are used in the wide range of industrial applications and are capable of handling single and multiphase fluids as compressors, expanders and pumps. Concentration of liquid in the inlet flow can influence the performance of the machine significantly. Characteristics of the multiphase flow at the suction of a screw compressor depend on the local flow velocities and concentration. Local flow velocity measurements inside the screw compressors are difficult to obtain. However other flow properties such as local pressures are easier to attain. It is therefore useful to carry out experiments with local pressure variations in the suction which can be used to validate the 3D numerical Computational Fluid Dynamic (CFD) models that could help in studying the single and multiphase flow behaviour in screw compressors. This paper presents experimental efforts to measure the local pressure losses inside the suction plenum of the screw compressor. Pressure variations are measured at 23 locations in the suction port at various operating conditions and compared with 3D CFD model. The grid generator SCORGTM was used for generating numerical mesh of rotors. The flow calculations were carried out using commercial 3D solver ANSYS CFX. It was found that the local pressure changes predicted by the CFD model are in the good agreement with measured pressures. This validated the use of CFD for modelling of the single phase flows in suction of screw machines.

  7. Improvement of Moderately Loaded Transonic Axial Compressor Performance Using Low Porosity Bend Skewed Casing Treatment

    Directory of Open Access Journals (Sweden)

    Dilipkumar Bhanudasji Alone


    Full Text Available This paper presents experimental results of a single stage transonic axial flow compressor coupled with low porosity bend skewed casing treatment. The casing treatment has a plenum chamber above the bend slots. The depth of the plenum chamber is varied to understand its impact on the performance of compressor stage. The performance of the compressor stage is evaluated for casing treatment and plenum chamber configurations at two axial locations of 20% and 40%. Experimental results reveal that the stall margin of the compressor stage increases with increase in the plenum chamber volume. Hot-wire measurements show significant reduction in the turbulence intensity with increase in the plenum chamber volume compared to that with the solid casing at the stall condition. At higher operating speeds of 80% and at 20% axial coverage, the stall margin of the compressor increases by 20% with half and full plenum depth. The improvement in the peak stage efficiency observed is 4.6% with half plenum configuration and 3.34% with the full plenum configuration. The maximum improvement in the stall margin of 29.16% is obtained at 50% operating speed with full plenum configurations at 40% axial coverage.

  8. Large eddy simulation of flows in industrial compressors: a path from 2015 to 2035. (United States)

    Gourdain, N; Sicot, F; Duchaine, F; Gicquel, L


    A better understanding of turbulent unsteady flows is a necessary step towards a breakthrough in the design of modern compressors. Owing to high Reynolds numbers and very complex geometry, the flow that develops in such industrial machines is extremely hard to predict. At this time, the most popular method to simulate these flows is still based on a Reynolds-averaged Navier-Stokes approach. However, there is some evidence that this formalism is not accurate for these components, especially when a description of time-dependent turbulent flows is desired. With the increase in computing power, large eddy simulation (LES) emerges as a promising technique to improve both knowledge of complex physics and reliability of flow solver predictions. The objective of the paper is thus to give an overview of the current status of LES for industrial compressor flows as well as to propose future research axes regarding the use of LES for compressor design. While the use of wall-resolved LES for industrial multistage compressors at realistic Reynolds number should not be ready before 2035, some possibilities exist to reduce the cost of LES, such as wall modelling and the adaptation of the phase-lag condition. This paper also points out the necessity to combine LES to techniques able to tackle complex geometries. Indeed LES alone, i.e. without prior knowledge of such flows for grid construction or the prohibitive yet ideal use of fully homogeneous meshes to predict compressor flows, is quite limited today.

  9. Aeroacoustic Simulation for NASA CC3 Centrifugal Compressor Operating at off Design Condition

    Directory of Open Access Journals (Sweden)

    Alqaradawi Mohamed


    Full Text Available This paper covers the characterization of the acoustic noise and the unsteady flow field of a high speed centrifugal compressor NASA CC3. In order to accurately predict the noise, all analyses are carried out through the use of Large Eddy Simulation and Ffowcs Williams–Hawkings model for noise prediction. The relative effect of hub cavity on flow characteristics and sound levels is investigated, for a compressor stage with a total pressure ratio equal to 4, working from surge to near choke condition. In comparison with the experimental results from literature, the predicted compressor performance and flow field are predicted well. The hub cavity flow effect on the compressor aeroacoustic generated noise is shown in the paper. The unsteady static pressure and sound pressure levels are compared not only at different location but also for design and off design operating points. The internal flow results inside the hub cavity are presented at surge, design and near choke points. The conclusion is that the cavity effect of the centrifugal compressor cannot be ignored in the numerical prediction of aerodynamic generated noise. The impeller back plate of the rotor experiences a strong pressure fluctuation, which is maxima at the impeller outer radius for all operating point, but higher pressure values at the surge point.

  10. Electrostatic descaling units on induction furnace and air compressor lines increase energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Girardi, A.G.


    Billions of gallons of water are consumed in the U.S. daily by countless industries-from paint formulators to manufacturers of semiconductors -as a heat transfer medium in process heating and cooling. Many of these systems are ''recirculating'' systems where process water is treated for scale and other contamination, then used over and over again. This technique is preferred where the water is relatively expensive, i.e., that which is supplied by a municipality. In other cases where well water is used, a ''once through'' system is preferred, with the water simply being discharged into the municipal waste stream.

  11. Development and Evaluation of an Online Air Quality Monitor (DIVEAIR2) for Diving Compressors (United States)


    Area Code) I 22c. OFFICE SYMBOL NEDU Librarian 850-230-3170 m 1 7 DD For 4 3 UNCLASSIFIED SECURITY CLASSIFICATION OF THIS PAGE SECURITY...gas delivery circuit just upstream from the analyzers by using a hand-held humidity and temperature meter (model HM70; Vaisala Oyj, Finland ), with

  12. Selection of the air heat exchanger operating in a gas turbine air bottoming cycle (United States)

    Chmielniak, Tadeusz; Czaja, Daniel; Lepszy, Sebastian


    A gas turbine air bottoming cycle consists of a gas turbine unit and the air turbine part. The air part includes a compressor, air expander and air heat exchanger. The air heat exchanger couples the gas turbine to the air cycle. Due to the low specific heat of air and of the gas turbine exhaust gases, the air heat exchanger features a considerable size. The bigger the air heat exchanger, the higher its effectiveness, which results in the improvement of the efficiency of the gas turbine air bottoming cycle. On the other hand, a device with large dimensions weighs more, which may limit its use in specific locations, such as oil platforms. The thermodynamic calculations of the air heat exchanger and a preliminary selection of the device are presented. The installation used in the calculation process is a plate heat exchanger, which is characterized by a smaller size and lower values of the pressure drop compared to the shell and tube heat exchanger. Structurally, this type of the heat exchanger is quite similar to the gas turbine regenerator. The method on which the calculation procedure may be based for real installations is also presented, which have to satisfy the economic criteria of financial profitability and cost-effectiveness apart from the thermodynamic criteria.

  13. Long-term Placement and Maintenance of Reciprocating Compressor%往复式压缩机长期放置维护

    Institute of Scientific and Technical Information of China (English)

    关洪浩; 董振; 王晓冬; 宋毅


    Good maintenance is to make the safe operation of the compressor unit, prolong service life, and to reduce running cost of the basic guarantee. Factory using many of the water-cooled reciprocating air compressors normal y is almost long-term operation in unattended condition, but normal maintenance ensures longer service life and trouble-free operation. Normal maintenance wil greatly reduce the production interruption and require expensive repair costs of accidents.%  良好的维护保养,是使压缩机组安全运行,延长使用寿命,并降低运行成本的基本保证。工厂使用的许多水冷往复式空气压缩机通常几乎是处于无人看管情况下长期运转的,但正常的维护保养可以保证更长的使用寿命和无故障运转。正常的维护保养将大大减少使生产中断并需要昂贵修理费用的事故。

  14. 变频压缩机低频周期性噪声的分析%Periodic Noise of Inverter Controlled Rotary Compressor

    Institute of Scientific and Technical Information of China (English)

    张荣婷; 黄辉; 胡余生; 徐嘉


    随着控制技术的发展,应用于空调系统的滚动转子压缩机的运行频率越来越低,甚至能达到1Hz。但随着运行频率降低至30Hz 以下时,压缩机会出现周期与压缩机运行频率相同的嗒嗒声,运行频率越低,周期性嗒嗒声越明显。本文采用滤波、时频分析及撞击试验等手段详细分析了周期性嗒嗒声产生的根源,并提出改进措施,有效改善低频哒哒声。%With the development of control technology,the operation frequency of compressor in air conditioner system is lower and lower,extremely to 1 Hz.A periodic noise appears when the compressor operating below 30Hz.The operating speed lower,the periodic noise become more obvious.In this paper,research is taken on the reason of this periodic noise with filter,time-frequency technology and impact experiment.What’s more,the structure is optimized to reduce the periodic noise.

  15. Measuring the electron beam energy in a magnetic bunch compressor

    Energy Technology Data Exchange (ETDEWEB)

    Hacker, Kirsten


    Within this thesis, work was carried out in and around the first bunch compressor chicane of the FLASH (Free-electron LASer in Hamburg) linear accelerator in which two distinct systems were developed for the measurement of an electron beams' position with sub-5 {mu}m precision over a 10 cm range. One of these two systems utilized RF techniques to measure the difference between the arrival-times of two broadband electrical pulses generated by the passage of the electron beam adjacent to a pickup antenna. The other system measured the arrival-times of the pulses from the pickup with an optical technique dependent on the delivery of laser pulses which are synchronized to the RF reference of the machine. The relative advantages and disadvantages of these two techniques are explored and compared to other available approaches to measure the same beam property, including a time-of-flight measurement with two beam arrival-time monitors and a synchrotron light monitor with two photomultiplier tubes. The electron beam position measurement is required as part of a measurement of the electron beam energy and could be used in an intra-bunch-train beam-based feedback system that would stabilize the amplitude of the accelerating field. By stabilizing the accelerating field amplitude, the arrival-time of the electron beam can be made more stable. By stabilizing the electron beam arrival-time relative to a stable reference, diagnostic, seeding, and beam-manipulation lasers can be synchronized to the beam. (orig.)

  16. An ultra-low-power image compressor for capsule endoscope

    Directory of Open Access Journals (Sweden)

    Weng Ping-Kuo


    Full Text Available Abstract Background Gastrointestinal (GI endoscopy has been popularly applied for the diagnosis of diseases of the alimentary canal including Crohn's Disease, Celiac disease and other malabsorption disorders, benign and malignant tumors of the small intestine, vascular disorders and medication related small bowel injury. The wireless capsule endoscope has been successfully utilized to diagnose diseases of the small intestine and alleviate the discomfort and pain of patients. However, the resolution of demosaicked image is still low, and some interesting spots may be unintentionally omitted. Especially, the images will be severely distorted when physicians zoom images in for detailed diagnosis. Increasing resolution may cause significant power consumption in RF transmitter; hence, image compression is necessary for saving the power dissipation of RF transmitter. To overcome this drawback, we have been developing a new capsule endoscope, called GICam. Methods We developed an ultra-low-power image compression processor for capsule endoscope or swallowable imaging capsules. In applications of capsule endoscopy, it is imperative to consider battery life/performance trade-offs. Applying state-of-the-art video compression techniques may significantly reduce the image bit rate by their high compression ratio, but they all require intensive computation and consume much battery power. There are many fast compression algorithms for reducing computation load; however, they may result in distortion of the original image, which is not good for use in the medical care. Thus, this paper will first simplify traditional video compression algorithms and propose a scalable compression architecture. Conclusion As the result, the developed video compressor only costs 31 K gates at 2 frames per second, consumes 14.92 mW, and reduces the video size by 75% at least.

  17. Sample of CFD optimization of a centrifugal compressor stage (United States)

    Galerkin, Y.; Drozdov, A.


    Industrial centrifugal compressor stage is a complicated object for gas dynamic design when the goal is to achieve maximum efficiency. The Authors analyzed results of CFD performance modeling (NUMECA Fine Turbo calculations). Performance prediction in a whole was modest or poor in all known cases. Maximum efficiency prediction was quite satisfactory to the contrary. Flow structure in stator elements was in a good agreement with known data. The intermediate type stage “3D impeller + vaneless diffuser+ return channel” was designed with principles well proven for stages with 2D impellers. CFD calculations of vaneless diffuser candidates demonstrated flow separation in VLD with constant width. The candidate with symmetrically tampered inlet part b3 / b2 = 0,73 appeared to be the best. Flow separation takes place in the crossover with standard configuration. The alternative variant was developed and numerically tested. The obtained experience was formulated as corrected design recommendations. Several candidates of the impeller were compared by maximum efficiency of the stage. The variant with gas dynamic standard principles of blade cascade design appeared to be the best. Quasi - 3D non-viscid calculations were applied to optimize blade velocity diagrams - non-incidence inlet, control of the diffusion factor and of average blade load. “Geometric” principle of blade formation with linear change of blade angles along its length appeared to be less effective. Candidates’ with different geometry parameters were designed by 6th math model version and compared. The candidate with optimal parameters - number of blades, inlet diameter and leading edge meridian position - is 1% more effective than the stage of the initial design.

  18. Experimental Studies on a Single Stage Stirling Type Pulse Tube Cryocooler Driven by Oil-Lubricated Compressor (United States)

    Jia, Ren; Jianying, Hu; Ercang, Luo; Xiaotao, Wang


    Because lubricating oil for moving parts is not allowed to go into the pulse tube cryocooler, Stirling type pulse tube cryocoolers are generally driven by oil-free compressors although oil-lubricated compressors are much cheaper and facile. Recently, it was proposed that an acoustic transparent and oil blocking diaphragm could be employed to separate the compressor and the cryocooler. Thus, the cryocooler can be driven by oil-lubricated compressors. In this paper, a pulse tube cryocooler is designed to match a crankcase compressor. Although the efficiency of the crankcase compressor is lower compared with the oil-free linear compressor, the crankcase compressor can easily work at lower frequency which results in higher efficiency for the cryocooler. So the relative high performance of the whole system can be maintained. In this system, the cryocooler delivers 28.5 W of cooling at 80 K with 680 W of electrical input power and operates at 15 Hz. The corresponding Carnot efficiency is 11.52%.

  19. 离心压缩机高位油箱喷油事故的原因分析%Analysis for cause of oil spray accident of elevated oil tank of centrifugal compressor

    Institute of Scientific and Technical Information of China (English)

    王娟; 郭孝武


    Unreasonable installation position of U-bend beneath the aspiration of oil return pipe of elevated oil tank results in oil spray from elevated oil tank during trial run of air compressor and oxygen compressor,which threatens safe run of the compressor.Here,the work principle of elevated oil tank is briefed,the causes for oil spray of elevated oil tank are analyzed,and the corresponding corrective measures are described.%由于高位油箱回油管呼吸孔下方的U形弯安装位置不合理,造成空压机和氧压机高位油箱在试运行过程中出现了喷油现象,威胁到压缩机的安全运行。介绍高位油箱的工作原理,分析高位油箱喷油的原因和相应整改措施。

  20. Study of Flow-Field Interactions in a Transonic Compressor using DPIV (United States)

    Estevadeordal, Jordi; Gogineni, Sivaram; Goss, Larry; Copenhaver, William; Gorrell, Steve; Koch, Peter


    The unsteadiness and spatial structures in a high-through-flow, axial-flow transonic compressor are captured using Digital Particle Image Velocimetry (DPIV). The measurements are made using both single-color and two-color DPIV systems. A special optical probe was designed for laser delivery through the inlet guide vanes (IGVs). Viewing windows on the compressor housing allow optical access. Submicron sized smoke particles are used for seeding the compressor flow and the DPIV system is synchronized with the blade passage. The interactions between the coherent structures from the IGVs with the rotor blades and the bow shock are studied for various configurations. The coherent structures interactions with the potential field of the leading edge of the blades and the shock as a function of the blade position are analyzed for a full blade passage through the wake. Comparisons are made with unsteady numerical simulations.

  1. Feasibility study of a periodic arc compressor in the presence of coherent synchrotron radiation (United States)

    Di Mitri, S.


    The advent of short electron bunches in high brightness linear accelerators has raised the awareness of the accelerator community to the degradation of the beam transverse emittance by coherent synchrotron radiation (CSR) emitted in magnetic bunch length compressors, transfer lines and turnaround arcs. Beam optics control has been proposed to mitigate that CSR effect. In this article, we enlarge on the existing literature by reviewing the validity of the linear optics approach in a periodic, achromatic arc compressor. We then study the dependence of the CSR-perturbed emittance to beam optics, mean energy, and bunch charge. The analytical findings are compared with particle tracking results. Practical considerations on CSR-induced energy loss and nonlinear particle dynamics are included. As a result, we identify the range of parameters that allows feasibility of an arc compressor for driving, for example, a free electron laser or a linear collider.

  2. The numerical simulation of a high-speed axial flow compressor (United States)

    Mulac, Richard A.; Adamczyk, John J.


    The advancement of high-speed axial-flow multistage compressors is impeded by a lack of detailed flow-field information. Recent development in compressor flow modeling and numerical simulation have the potential to provide needed information in a timely manner. The development of a computer program is described to solve the viscous form of the average-passage equation system for multistage turbomachinery. Programming issues such as in-core versus out-of-core data storage and CPU utilization (parallelization, vectorization, and chaining) are addressed. Code performance is evaluated through the simulation of the first four stages of a five-stage, high-speed, axial-flow compressor. The second part addresses the flow physics which can be obtained from the numerical simulation. In particular, an examination of the endwall flow structure is made, and its impact on blockage distribution assessed.

  3. Determination of the Optimal Operating Parameters for Jefferson Laboratory's Cryogenic Cold Compressor Systems

    Energy Technology Data Exchange (ETDEWEB)

    Joe D. Wilson, Jr.


    The technology of Jefferson Laboratory's (JLab) Continuous Electron Beam Accelerator Facility (CEBAF) and Free Electron Laser (FEL) requires cooling from one of the world's largest 2K helium refrigerators known as the Central Helium Liquefier (CHL). The key characteristic of CHL is the ability to maintain a constant low vapor pressure over the large liquid helium inventory using a series of five cold compressors. The cold compressor system operates with a constrained discharge pressure over a range of suction pressures and mass flows to meet the operational requirements of CEBAF and FEL. The research topic is the prediction of the most thermodynamically efficient conditions for the system over its operating range of mass flows and vapor pressures with minimum disruption to JLab operations. The research goal is to find the operating points for each cold compressor for optimizing the overall system at any given flow and vapor pressure.

  4. CFD comparison with centrifugal compressor measurements on a wide operating range

    Directory of Open Access Journals (Sweden)

    Arnou D.


    Full Text Available Centrifugal compressors are widely used in industrial applications thanks to their high efficiency. They are able to provide a wide operating range before reaching the flow barrier or surge limits. Performances and range are described by compressor maps obtained experimentally. After a description of performance test rig, this article compares measured centrifugal compressor performances with computational fluid dynamics results. These computations are performed at steady conditions with R134a refrigerant as fluid. Navier-Stokes equations, coupled with k-ε turbulence model, are solved by the commercial software ANSYS-CFX by means of volume finite method. Input conditions are varied in order to calculate several speed lines. Theoretical isentropic efficiency and theoretical surge line are finally compared to experimental data.

  5. Modelling of fluid flow and heat transfer in a reciprocating compressor (United States)

    Tuhovcak, J.; Hejcik, J.; Jicha, M.


    Efficiency of reciprocating compressor is strongly dependent on several parameters. The most important are valve behaviour and heat transfer. Valves affect the flow through the suction and discharge line. Heat flow from the walls to working fluid increases the work of the cycle. Understanding of these phenomena inside the compressor is a necessary step in the development process. Commercial CFD tools offer wide range of opportunities how to simulate the flow inside the reciprocating compressor nowadays, however they are too demanding in terms of computational time and mesh creation. Several approaches using various correlation equation exist to describe the heat transfer inside the cylinder, however none of them was validated by measurements due to the complicated settings. The goal of this paper is to show a comparison between these correlations using in-house code based on energy balance through the cycle.

  6. Principle and Thermodynamic Process of the Compressor of Composite Gear Teeth

    Institute of Scientific and Technical Information of China (English)

    XIONG Wei; YU Xiao-ling; PENG Xue-yuan; FENG Quan-ke


    The compressor of composite gear teeth is a new type of rotor compressor with partial built-in compression process. Analysis of its thermodynamic process indicates that the built-in process is incomplete. The thermodynamic process of the compressor of composite gear teeth can be considered as five processes: the suction process, the isometric process, the compression process, the pressure-balance process at high pressure and low pressure gas, and discharge process. Here, it is necessary to explain further the pressure-balance process. The pressure-balance process is isometric process. It is found that the isometric process of gas in chamber A whose capacity is 83 percent of total work volume can be eliminated basically through extending the discharge port to connect early the discharge port with the chamber B. By the above-mentioned method, the loss of energy will be reduced.

  7. Numerical Investigation & Comparison of a Tandem-Bladed Turbocharger Centrifugal Compressor Stage with Conventional Design

    Institute of Scientific and Technical Information of China (English)

    Syed Noman Danish; Shafiq Rehman Qureshi; Abdelrahman EL-Leathy; Salah Ud-Din Khan; Usama Umer; Ma Chaochen


    Extensive numerical investigations of the performance and flow structure in an unshrouded tandem-bladed centrifugal compressor are presented in comparison to a conventional compressor.Stage characteristics are explored for various tip clearance levels,axial spacings and circumferential clockings.Conventional impeller was modified to tandem-bladed design with no modifications in backsweep angle,meridional gas passage and camber distributions in order to have a true comparison with conventional design.Performance degradation is observed for both the conventional and tandem designs with increase in tip clearance.Linear-equation models for correlating stage characteristics with tip clearance are proposed.Comparing two designs,it is clearly evident that the conventional design shows better performance at moderate flow rates.However; near choke flow,tandem design gives better results primarily because of the increase in throat area.Surge point flow rate also seems to drop for tandem compressor resulting in increased range of operation.

  8. Optical terminal analysis of a multigrating tiled compressor in a PW-class CPA-laser

    Institute of Scientific and Technical Information of China (English)

    Yang Yu-Chuan; Luo Hui; Wang Xiao; Li Fu-Quan; Huang Xiao-Jun; Jing Feng


    In the highest-power chirped-pulse amplification lasers,the pulse must be stretched in time,amplified,compressed in a grating compressor and subsequently focused by off-axis parabola to obtain a high peak power.In the optical terminal,the temporal and spatial effects of mismatched multigrating tiled compressor on the far-field pulse axe critical factors to be analysed.In this paper,a k-space raytracing model is proposed for the temporal and spatial analyses of possible errors in a four-grating single-pass tiled compressor.The results show that the last grating affects mainly the partial focal spot,while the middle two gratings affect the temporal waveform,and the partial focal spot needs much higher error control than that in the temporal domain in a picosecond pulse compression.

  9. Aerodynamic and mechanical design of an 8:1 pressure ratio centrifugal compressor (United States)

    Osborne, C.; Runstadler, P. W., Jr.; Stacy, W. D.


    A high-pressure-ratio, low-mass-flow centrifugal compressor stage was designed, fabricated, and tested. The design followed specifications that the stage be representative of state-of-the-art performance and that the stage is to be used as a workhorse compressor for planned experiments using laser Doppler velocimeter equipment. The final design is a 75,000-RPM, 19-blade impeller with an axial inducer and 30 degrees of backward leaning at the impeller tip. The compressor design was tested for two- and/or quasi-three-dimensional aerodynamic and stress characteristics. Critical speed analyses were performed for the high speed rotating impeller assembly. An optimally matched, 17-channel vane island diffuser was also designed and built.

  10. Feasibility study of a periodic arc compressor in the presence of coherent synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Di Mitri, S.


    The advent of short electron bunches in high brightness linear accelerators has raised the awareness of the accelerator community to the degradation of the beam transverse emittance by coherent synchrotron radiation (CSR) emitted in magnetic bunch length compressors, transfer lines and turnaround arcs. Beam optics control has been proposed to mitigate that CSR effect. In this article, we enlarge on the existing literature by reviewing the validity of the linear optics approach in a periodic, achromatic arc compressor. We then study the dependence of the CSR-perturbed emittance to beam optics, mean energy, and bunch charge. The analytical findings are compared with particle tracking results. Practical considerations on CSR-induced energy loss and nonlinear particle dynamics are included. As a result, we identify the range of parameters that allows feasibility of an arc compressor for driving, for example, a free electron laser or a linear collider.

  11. Optimal r/b ratio of bend channel in centrifugal compressor

    Institute of Scientific and Technical Information of China (English)

    Suping WEN; Xiaowen HU; Yong ZHANG; Jun WANG; Tingbin LI


    A numerical investigation on the flow in a bend channel by coupling the impeller with the vaneless diffuser in a centrifugal compressor with different r/b ratios (bend radius r to bend channel width b) is presented. The jet-wake effect of the impeller outlet is considered and flow pattern in the bend channel and the performance of the centrifugal compressor stage are investigated. The results indicate that there is an optimal r/b ratio for increasing the stage efficiency to the highest for a specific compressor stage. The change in r/b ratio significantly affects the flow angle of the bend chan-nel outlet. The prime reason for the total pressure loss in the bend channel is the wall friction in the bend channel.

  12. Dynamic behavior of valve system in linear compressor based on fluid-structure interaction

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yong Sik; Lee, Jun Ho; Jeong, Weui Bong [Pusal National University, Busan (Korea, Republic of); Kim, Il Geun [Locus Company Limited, Busan (Korea, Republic of)


    In refrigerator designs, the linear compressor is preferable to the recipro-type compressor, due to its higher energy efficiency. The linear compressor's valve system, however, causes significant noise, not only in the steady state but also in the transient state. To accurately predict the behavior of the suction and discharge valve system in both states, the interaction between the fluid flowing through the valves and the structural deformation of the valves needs to be understood. In the present study, the steady-state behaviors of the valve system were numerically analyzed using ADINA software, which takes fluid-structure interaction (FSI) into account. This computational analysis thereafter was experimentally validated. The effects of a pre-load of the conical compression spring on the dynamic characteristics of the valve system also were analyzed

  13. Rotor Design for an Efficient Single-Phase Induction Motor for Refrigerator Compressors

    Directory of Open Access Journals (Sweden)

    Hyun-Jin Ahn


    Full Text Available This article describes a rotor making technology for the production of high-efficiency single-phase induction motors (SPIMs to be used in refrigerator compressors. Rotors can have different aluminum fill factors according to the fabrication method. In order to examine the association between the fill factor and the efficiency of the rotor, we analyzed the distribution of magnetic flux density using the finite element method (FEM. Next, we made prototype rotors by conventional casting methods and by the proposed casting method and compared their fill factors. In addition, SPIMs were made using the rotors, and their efficiencies were measured using a dynamometer. Moreover, the SPIMs were put to use in a compressor, for testing, and for each SPIM the refrigerating capacity of the compressor was measured with a calorimeter. Based on the results of the FEM analysis of the magnetic flux density and the experiments, the reliability and validity of the proposed method were proven.

  14. A parametric optimization procedure for the suction system of reciprocating compressors (United States)

    Ferreira, W. M.; Silva, E.; Deschamps, C. J.


    The design of the suction system of compressors is of fundamental importance for efficiency and reliability. This paper reports a method developed to optimize the suction system of a reciprocating compressor, by using the genetic algorithm NSGA-II. The isentropic and volumetric efficiencies are used as objective functions, while the bending fatigue stress is used as a constraint to meet valve reliability. A simulation model of the compression cycle was coupled to the optimization procedure, with correlations for flow and force effective areas in terms of geometric parameters of the suction valve. Valve dynamics was numerically solved via the finite element method. The proposed optimization procedure was applied to a reciprocating compressor adopted for household refrigeration, identifying suction system geometries more efficient than the original design.

  15. Numerical analysis and optimization of the inlet stage of a multi-stage high pressure compressor

    Institute of Scientific and Technical Information of China (English)

    XU Quan-yong; HOU An-ping; XIONG Jin-song; ZHOU Sheng


    An optimization process is used to redesign blades of a high-pressure compressor. An artificial neural network (ANN) method is coupled to Navier-Stokes solvers and is applied to three different redesigns. A new rotor blade of a transonic compressor is designed by modifying thick, stacking line and inlet angle using a 3D approach, with a significant efficiency improvement at the design point. The off-design behavior of this new compressor is also checked afterwards, which shows that the whole performance of the inlet stage is improved over a wide range of mass flow. The losses are reduced, proving the good performance of the optimum. The whole results indicate that the optimization method can find improved design and can be integrated in a design procedure.

  16. Evaluation of turbine systems for compressed air energy storage plants. Final report for FY 1976

    Energy Technology Data Exchange (ETDEWEB)

    Kartsounes, G.T.


    Compressed air energy storage plants for electric utility peak-shaving applications comprise four subsystems: a turbine system, compressor system, an underground air storage reservoir, and a motor/generator. Proposed plant designs use turbines that are derived from available gas and steam turbines with proven reliability. The study examines proposed turbine systems and presents an evaluation of possible systems that may reduce capital cost and/or improve performance. Six new turbine systems are identified for further economic evaluation.

  17. Stall Inception Process and Prospects for Active Hub-Flap Control in Three-Stage Axial Flow Compressor

    Institute of Scientific and Technical Information of China (English)

    Tomoya OKADA; Atsushi KAWAJIRI; Yutaka OHTA; Eisuke OUTA


    The possibility to apply the active hub-flap control method, which is a proven rotating stall control method for a single-stage compressor, to a 3-stage axial compressor is experimentally discussed, where complex rotating stall inception processes ate observed. The research compressor is a 3-stage one and could change the stagger angle settings for rotor blades and stator vanes. Sixteen rotor blade/stator vane configuration patterns were tested by changing stagger angle for the stator vanes. By measurement of surface-pressure fluctuation, stall inception proc-esses are investigated and the measured pressure fluctuation data is used as a predictive signal for rotating stall. The experimental results show that the stall detection system applied to active hub-flap control in a single-stage compressor could be usefully applied to that in a 3-stage compressor with a more complex stall inception process.

  18. Theoretical and experimental investigations on the dynamic and thermodynamic characteristics of the linear compressor for the pulse tube cryocooler (United States)

    Zhang, L.; Dang, H. Z.; Tan, J.; Bao, D.; Zhao, Y. B.; Qian, G. Z.


    Theoretical and experimental investigations on the dynamic and thermodynamic characteristics of a linear compressor incorporating the thermodynamic characteristics of the inertance tube pulse tube cold finger have been made. Both the compressor and cold finger are assumed as a one-dimensional thermodynamic model. The governing equations of the thermodynamic characteristics of the working gas are summarized, and the effects of the cooling performance on the working gas in the compression space are discussed. Based on the analysis of the working gas, the governing equations of the dynamic and thermodynamic characteristics of the compressor are deduced, and then the principles of achieving the optimal performance of the compressor are discussed in detail. Systematic experimental investigations are conducted on a developed moving-coil linear compressor which drives a pulse tube cold finger, which indicate the general agreement with the simulated results, and thus verify the rationality of the theoretical model and analyses.

  19. Reciprocating and Screw Compressor semi-empirical models for establishing minimum energy performance standards (United States)

    Javed, Hassan; Armstrong, Peter


    The efficiency bar for a Minimum Equipment Performance Standard (MEPS) generally aims to minimize energy consumption and life cycle cost of a given chiller type and size category serving a typical load profile. Compressor type has a significant chiller performance impact. Performance of screw and reciprocating compressors is expressed in terms of pressure ratio and speed for a given refrigerant and suction density. Isentropic efficiency for a screw compressor is strongly affected by under- and over-compression (UOC) processes. The theoretical simple physical UOC model involves a compressor-specific (but sometimes unknown) volume index parameter and the real gas properties of the refrigerant used. Isentropic efficiency is estimated by the UOC model and a bi-cubic, used to account for flow, friction and electrical losses. The unknown volume index, a smoothing parameter (to flatten the UOC model peak) and bi-cubic coefficients are identified by curve fitting to minimize an appropriate residual norm. Chiller performance maps are produced for each compressor type by selecting optimized sub-cooling and condenser fan speed options in a generic component-based chiller model. SEER is the sum of hourly load (from a typical building in the climate of interest) and specific power for the same hourly conditions. An empirical UAE cooling load model, scalable to any equipment capacity, is used to establish proposed UAE MEPS. Annual electricity use and cost, determined from SEER and annual cooling load, and chiller component cost data are used to find optimal chiller designs and perform life-cycle cost comparison between screw and reciprocating compressor-based chillers. This process may be applied to any climate/load model in order to establish optimized MEPS for any country and/or region.

  20. Characterization of sorption compressor for mixed refrigerant J-T cryocooler (United States)

    Mehta, Rohitkumar; Bapat, Shridhar; Atrey, Milind


    The requirement of a cryocooler with minimum vibrations for space borne system and highly sophisticated electronic devices for ground application, has led to the development of sorption compressor type J-T cryocooler. The adsorption capacity of any adsorbent material increases with an increase in pressure and decreases with an increase in temperature. In a Sorption compressor, adsorbed gases are desorbed in a confined volume by raising temperature of the sorption bed which results in increase in pressure of gas. A uniform temperature across the sorption bed ensures maximum discharge from the compressor amounting to higher flow rates and longer cycle time on account of reduced residual loading. In addition, it is also very important to determine the adsorption capacity of any material with respect to the gas or gases to be adsorbed as this varies with source of the adsorbent. The present work reports the characterization of a fully operational two-cell sorption compressor developed. The sorption compressor is characterized for discharge pressure variation with cycle time; this is essentially a function of a) the amount of adsorbent, b) the adsorption capacity for respective gas or gases, c) desorption temperature and its uniformity, and d) system dead volume. The present paper analyses these aspects theoretically and the results are compared with the experimental data obtained for individual gases as well as for gas mixtures. The effect of gas distribution on temperature uniformity across the bed and of heater power on high pressure generated is also studied. The paper also discusses the pressure profile obtained for a given amount of adsorbent for different gas or gas mixture. The work, based on the results obtained so far is being further extended for a four cell sorption compressor.