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Articles 2257561 - 2257590 of 5160153

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A Simplified Cfd Model For Simulation Of The Suction Process Of Reciprocating Compressors, Evandro L. L. Pereira, Claudio J. Santos, Cesar J. Deschamps, Rodrigo Kremer Jul 2012

A Simplified Cfd Model For Simulation Of The Suction Process Of Reciprocating Compressors, Evandro L. L. Pereira, Claudio J. Santos, Cesar J. Deschamps, Rodrigo Kremer

International Compressor Engineering Conference

The suction process in reciprocating compressors is strongly affected by the valve dynamics and the pulsating flow throughout the suction muffler. This paper describes a simplified computational fluid dynamics (CFD) model to simulate the flow through the muffler, suction valve and a small region inside the cylinder. The proposed method is applied to predict the suction process of a small reciprocating compressor and its adequacy is compared with a more time elaborate model in terms of accuracy, computation cost and usability.

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Performance Investigation Of Linear Compressor With One Side Springs, Huiming Zou, Shuangquan Shao, Mingsheng Tang, Liqin Zhang, Guohong Peng Jul 2012

Performance Investigation Of Linear Compressor With One Side Springs, Huiming Zou, Shuangquan Shao, Mingsheng Tang, Liqin Zhang, Guohong Peng

International Compressor Engineering Conference

In this paper a linear compressor prototype with a set of cylindrical coil springs connected to one side of the trestle is developed. The initial position of piston head is near to the top dead center and coil springs are on free status. The experiments on the prototype are carried out by compressing air on different working conditions. The experimental results show that the linear compressor with one side springs can take good advantage of the gas springcharacteristics of the compressed work fluid to reduce the stiffness of mechanical spring and the weight of compressor. However the mechanical springs cannot …

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A Rotary Compressor-Accumulator Component Simulation Model In Consideration Of (±) Suction Gas Superheat Degrees, Ke-Jia Ye, Hong Tao, Jun Yang, Chun-Hui Liu Jul 2012

A Rotary Compressor-Accumulator Component Simulation Model In Consideration Of (±) Suction Gas Superheat Degrees, Ke-Jia Ye, Hong Tao, Jun Yang, Chun-Hui Liu

International Compressor Engineering Conference

On the basis of the classic ARI compressor model, the mass flow-rate and input power were corrected with the level of suction gas superheat, especially the superheat degrees below zero. refrigerant dissolved in the oil pool, at the discharge pressure and the oil temperature, was calculated by means of the estimation model for refrigerant/oil mixture properties. An accumulator mechanism model was linked to this compressor model to build up a compressor-accumulator component model, which was solved out by the simultaneous modular algorithm. The component model can afford more details about the performance of rotary compressor and refrigerant distribution, furthermore, can …

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Use Of New Generation Instruments In Measurement Of New Steam Expander, Ashvin Dhunput, Ian K. Smith, Nikola Stosic, Ahmed Kovacevic Jul 2012

Use Of New Generation Instruments In Measurement Of New Steam Expander, Ashvin Dhunput, Ian K. Smith, Nikola Stosic, Ahmed Kovacevic

International Compressor Engineering Conference

For the past twenty years the Centre for Positive Displacement Compressor Technology, at City University, has employed experimental techniques for the measurement of screw compressors’ performance where both experimental data and predicted mathematical models are found to be in agreement with each other. Some of the experimental measuring techniques involve the use of pressure and temperature transducers installed in the housing to determine the vital thermodynamic process characteristics and functioning performance of compressors. Moreover, as advanced technologies were available, measurements were performed in an optical compressor with a transparent window near the discharge port to allow the application of a …

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R32 Compressor For Air Conditioning And Refrigeration Applications In China, Weihua Guo, Gaofeng Ji, Honghong Zhan, Dan Wang Jul 2012

R32 Compressor For Air Conditioning And Refrigeration Applications In China, Weihua Guo, Gaofeng Ji, Honghong Zhan, Dan Wang

International Compressor Engineering Conference

This paper evaluates the compressor performance and reliability impact by using R32 refrigerant for air conditioning (residential and commercial system); Performance and reliability impacts are compared with different popular refrigerants used in China, for example, R410A & R22 for AC. The design improvement on the scroll compressor will be discussed in order to reach required efficiency and reliability; these improvements include lubrication, internal heat management, motor design, and vapor injection technologies, etc.

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Modelling Of An Air Compressor Using Energetic Macroscopic Representation, Mahbod Heidari, Martel Tsirinomeney, Alfred Rufer, Philippe Barrade Jul 2012

Modelling Of An Air Compressor Using Energetic Macroscopic Representation, Mahbod Heidari, Martel Tsirinomeney, Alfred Rufer, Philippe Barrade

International Compressor Engineering Conference

This article introduces the energetic macroscopic representation (EMR) as approach for the dynamic nonlinear modeling of a reciprocating air compressor. EMR has been introduced recently for research development in complex electromechanical systems. It is based on action reaction principle, which organizes the system as interconnected subsystems according to the integral causality. The graphical modeling based on EMR has advantages such as readability, modularity, structural and functional characteristics. The EMR is the first step toward model-based control structure development. The air compressor system containing: slider-crank mechanism, cylinder head and valves, is divided into multitude simple subsystems. Each subsystem describes an elementary …

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Investigation Of Start Up Process In Oil Flooded Twin Screw Compressors, Ekaterina Chukanova, Nikola Stosic, Ahmed Kovacevic, Ashvin Dhunput Jul 2012

Investigation Of Start Up Process In Oil Flooded Twin Screw Compressors, Ekaterina Chukanova, Nikola Stosic, Ahmed Kovacevic, Ashvin Dhunput

International Compressor Engineering Conference

Oil injected screw compressors used for air applications and refrigeration are usually installed in simple packages which often do not include oil pump for supply of oil to the bearings and the working chamber. The period of an unlubricated operation depends on the size of the oil system and the length of the discharge piping. When the back pressure reaches the chamber pressure, a normal mode of lubrication will start. Due to the lack of lubrication, rotors will be in direct contact with insufficient or no oil film between them, while the pressure in the compression chamber will increase causing …

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Development Of R744 Two Stage Compressor For Commercial Heat Pump Water Heater, Youhei Hotta, Yoshiyuki Kimata, Hajime Sato, Hiroyuki Kobayashi, Hisao Mizuno Jul 2012

Development Of R744 Two Stage Compressor For Commercial Heat Pump Water Heater, Youhei Hotta, Yoshiyuki Kimata, Hajime Sato, Hiroyuki Kobayashi, Hisao Mizuno

International Compressor Engineering Conference

A novel CO2 two stage compressor has been developed. The developed compressor equips one rotary and one scroll compression chambers as first and second stage respectively. For efficiency improvement, authors measured the cylinder pressure in each stage and conducted loss classification in the compressor. By adopting appropriate compression type in each stage, and by decreasing critical loss found by measuring the pressure, it resulted in 6% and 10% improvement of heating capacity and COP respectively on rated condition, and 25% and over 50% improvement on deep-frozen condition compared with conventional single stage compressor. The developedcompressor is installed on our newly …

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Optimization Of Compression Chamber To Reduce The Viscous Friction In The Piston-Cylinder Clearance, Rodrigo Link Jul 2012

Optimization Of Compression Chamber To Reduce The Viscous Friction In The Piston-Cylinder Clearance, Rodrigo Link

International Compressor Engineering Conference

The compression chamber of a hermetic reciprocating compressor is, normally, formed by a cylinder and a piston which present a constant clearance during the piston displacement inside the compression chamber. This configuration has the advantage of a good sealing, however, during the most part of compression, the pressure difference between compression chamber and internal compressor ambient is small enough to not provide any leakage from chamber to internal ambient. In this situation, during the most part of compression process, the sealing efficiency is not necessary, but the high viscous friction, due the small clearance between piston and cylinder, generates a …

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Development Of An In-Cylinder Heat Transfer Correlation For Reciprocating Compressors, Fernanda P. Disconzi, Cesar J. Deschamps, Evandro L. L. Pereira Jul 2012

Development Of An In-Cylinder Heat Transfer Correlation For Reciprocating Compressors, Fernanda P. Disconzi, Cesar J. Deschamps, Evandro L. L. Pereira

International Compressor Engineering Conference

The gas superheating that takes place throughout the suction system and inside the cylinder of reciprocating compressors adversely affects their overall efficiency. Simulation models adopted in the design of reciprocating compressors are generally based on lumped formulation and rely on empirical correlations for different physical phenomena, including the gas-to-wall heat transfer in the cylinder. The present paper reports a numerical study of heat transfer inside the cylinder of a simplified geometry of reciprocating compressor, considering the effect of fluid flow through the valves. Predictions for the instantaneous heat transfer at the walls are obtained for actual operating conditions and compared …

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Study On A Cooling System For Rotary Compressor, Haifeng Zhang, Shuoyuan Wang, Fei Xie Jul 2012

Study On A Cooling System For Rotary Compressor, Haifeng Zhang, Shuoyuan Wang, Fei Xie

International Compressor Engineering Conference

It is well known that the isothermal compression is an ideal process to consume least power for compressor. The isothermal compression can't be really reached, but can be approached by decreasing the discharge temperature during compression. For this purpose, a cooling system has been built in the paper. Firstly, an innovative circulation system has been built to absorb the heat generated by compression, which is segregated from the refrigeration circulation system. The principle and the structure are introduced. Then, the experimental has been conducted. Based on the experimental, the following results has be obtained: The cooling capacity increased by 1.3%; …

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The Influence Of Optimization Algorithm On Suction Muffler Design, Talita Wajczyk, Rodrigo Link Jul 2012

The Influence Of Optimization Algorithm On Suction Muffler Design, Talita Wajczyk, Rodrigo Link

International Compressor Engineering Conference

The standards for refrigerators energy consumption are increasing faster in the recent past years, so, the situation demands compressor with a higher efficiency level. To develop such compressors the performance of the most important compressor´s components must be increased. However, the pressure for fast time to market are turning more difficulty the optimization process of a big amount of components, specially using experimental validations. One of the most important components in the compressor is the suction muffler. The main suction muffler functions are the thermal insulation of gas from the evaporator and noise attenuation. To increase the performance of muffler …

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Effect Of The Turbulence Modeling In The Prediction Of Heat Transfer In Suction Mufflers, Tadeu Tonheiro Rodrigues, Rodrigo Link Jul 2012

Effect Of The Turbulence Modeling In The Prediction Of Heat Transfer In Suction Mufflers, Tadeu Tonheiro Rodrigues, Rodrigo Link

International Compressor Engineering Conference

The well-grounded knowledge of the available numerical methods is of fundamental importance to get advantage of computational aided design. Concerning compressor development, the employment of Computational Fluid Dynamics is nowadays a must, however, very little attention has been given to the importance of the turbulence modeling in the prediction of flow behavior and, moreover, the heat transfer. The present paper reports an investigation of the turbulence models influence in the heat transfer prediction of the compressor suction system, specifically the suction muffler. The importance of the correct heat transfer modeling in the suction muffler represents great importance for the computation …

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Visualization Of Flow In Scroll Compressor By Radiography, Masatsugu Chikano, Hayato Shimizu, Takeshi Tsuchiya, Kenji Tojo Jul 2012

Visualization Of Flow In Scroll Compressor By Radiography, Masatsugu Chikano, Hayato Shimizu, Takeshi Tsuchiya, Kenji Tojo

International Compressor Engineering Conference

Saving energy and resources in the air conditioning industry is required in order to protect the global environment. To save resources, miniaturization of the compressor in air conditioners is necessary. This miniaturization will increase the oil circulation rate (OCR) of the compressor because the oil separation space will be reduced. To improve the oil separation efficiency, it is necessary to understand the appearance of the flow of oil and refrigerant in the compressor chamber. This paper reports a technique to visualize the flow by using neutron radiography and X-ray radiography. Furthermore, a method to measure the oil concentration by carrying …

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Modal Analysis Of The Rotor-Journal Bearing System Of Rotary Compressor, Zengli Wang, Quanke Feng, Fangyuan Zhang, Xiaoling Yu Jul 2012

Modal Analysis Of The Rotor-Journal Bearing System Of Rotary Compressor, Zengli Wang, Quanke Feng, Fangyuan Zhang, Xiaoling Yu

International Compressor Engineering Conference

In the rotary compressor, the rolling piston and the contacted rotor-journal bearing system are basically moving components. Because of the inertia forces and the periodically changing gas force acting on the rolling piston and the rotor, the journal bearing suffers very large loads. It always leads to serious vibration of the rotor-journal bearing system, and the wear of the rotor. Thus, the vibration must be reduced. In this paper, research works of vibration characteristics of the rotor-journal bearing system were carried out to provide evident of optimizing its structure to reduce the vibration. The average values of the natural frequencies …

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A Valve Design Methodology For Improved Reciprocating Compressor Performance, Aditya Bhakta, Sandeep Dhar, Vaibhav Bahadur, Shruti Angadi, Subhrajit Dey Jul 2012

A Valve Design Methodology For Improved Reciprocating Compressor Performance, Aditya Bhakta, Sandeep Dhar, Vaibhav Bahadur, Shruti Angadi, Subhrajit Dey

International Compressor Engineering Conference

The current work directly relates valve dynamics to the compressor energy efficiency. Majority of the previous studies have focused on reducing pressure losses due to valve geometry, towards improved compressor performance. On a complimentary note, analyzing the valve ‘flutter’ leads to a holistic valve development methodology. Traditionally, pressure actuated reed valves have been used in reciprocating hermetic compressors on the suction and discharge ports. A characteristic of these valve operation is the multiple opening and closing motions, during a single suction and discharge pulse, often referred to as the ‘valve flutter’. This is more prominent for the suction reed considering …

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Abnormal Compressor Noise Diagnosis Using Sound Quality Evaluation And Acoustic Array Method, Jinquan Zhang, Rongting Zhang, Huanhuan Gu, Zhiming Wen, Jia Xu Jul 2012

Abnormal Compressor Noise Diagnosis Using Sound Quality Evaluation And Acoustic Array Method, Jinquan Zhang, Rongting Zhang, Huanhuan Gu, Zhiming Wen, Jia Xu

International Compressor Engineering Conference

A noise abnormal rotary compressor is analyzed with sound quality evaluation method. Sound power level (A), loudness, roughness and sharpness are calculated as objective evaluation parameters, and the results indicate that the abnormal compressor has a poor sound quality compared with a normal one. Acoustic array technique can identify target sound source of complicated shape accurately, and get rich sound field information compared to traditional near-field measurement with a sound level meter. In order to diagnose the abnormal noise, the compressor sound sources are identified and located in full frequency range through acoustic array method. As a result, the key …

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A New Design Of The Tooth Profile For Single Screw Compressors, Jian Li, Feilong Liu, Quanke Feng, Weifeng Wu Jul 2012

A New Design Of The Tooth Profile For Single Screw Compressors, Jian Li, Feilong Liu, Quanke Feng, Weifeng Wu

International Compressor Engineering Conference

The wear of star wheel teeth is an importance issue in the single screw compressor. In order to enhance the wearresistance of star wheel teeth, some new profiles of the meshing pair were proposed to replace the currently used straight line envelope profile, such as single column envelope, multi-straight line (or multi-column) envelope. In this paper, a curved surface of the tooth flank is suggested. The groove flank is the envelope surface corresponding to the curved surface of the tooth flank. Section profile of the new tooth flank is a curved line, which could be elliptical, hyperbolic or involute. During …

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Performance And Operating Characteristics Of A Novel Rotating Spool Compressor, Joe Orosz, Greg Kemp, Craig Bradshaw, Eckhard A. Groll Jul 2012

Performance And Operating Characteristics Of A Novel Rotating Spool Compressor, Joe Orosz, Greg Kemp, Craig Bradshaw, Eckhard A. Groll

International Compressor Engineering Conference

The basic mechanism of the novel rotary spool compressor has been described previously by Kemp et al. (2008, 2010). The device combines various aspects of rotary and reciprocating devices currently well understood to achieve high efficiency at a low manufacturing cost. A dimensionless variable, the Zsoro number, is developed which represents the ratio of the geometric configuration of the compressor relative to the potential friction components of the compressor. This number allows for rapid evaluation of the geometric features of the device. Four prototype spool compressors have been tested using R410A and R134A at standard air conditioning conditions with various …

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Development Of A R744 Low Side Variable Speed Scroll Compressor For Bottle Cooler Application, Yueh-Ju Tang, Yangguang Liu Jul 2012

Development Of A R744 Low Side Variable Speed Scroll Compressor For Bottle Cooler Application, Yueh-Ju Tang, Yangguang Liu

International Compressor Engineering Conference

The application of carbon dioxide as natural refrigerant in commercial refrigeration systems has attracted higher interest in recent years for its promising energy efficiency and ecological sustainability. This paper presented the development of a low side scroll compressor for the bottle cooler application in the trans-critical cycle. Experimental tests were performed in two different temperatures of the outlet refrigerant of the gas cooler with the same operation speed. For comparison of performance of the prototype, a small commercial reciprocating compressor was tested at the same operational conditions. Experimental results show that scroll compressor performed significantly better than the small commercial …

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Spool Compressor Tip Seal Design Considerations And Testing, Greg Kemp, Joe Orosz, Craig Bradshaw, Eckhard A. Groll Jul 2012

Spool Compressor Tip Seal Design Considerations And Testing, Greg Kemp, Joe Orosz, Craig Bradshaw, Eckhard A. Groll

International Compressor Engineering Conference

The simple analysis, design, construction and testing of the spool compressor’s tip seal is presented. Analysis yields key design considerations for seal geometry, preloading and pressure balance. Several seal designs are constructed and tested for leakage. Volumetric efficiency is calculated for three tip seal configurations and presented as a function of pressure ratio. It is determined that a two piece seal that expands axially results in less leakage. Further, it is determined that fluid pressure activation of the tip seal improves performance and eliminates the need for a highly loaded biasing spring. It is concluded that the tip seal performance …

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Spool Seal Design And Testing For The Spool Compressor, Greg Kemp, Joe Orosz, Craig Bradshaw, Eckhard A. Groll Jul 2012

Spool Seal Design And Testing For The Spool Compressor, Greg Kemp, Joe Orosz, Craig Bradshaw, Eckhard A. Groll

International Compressor Engineering Conference

Several seals, designed to minimize leakage between the rotating spool assembly’s endplates and the stationary compressor housing, are introduced, constructed and tested. Some designs are deemed impractical due to either high leakage or high torque. A novel one piece hybrid design that blends the function of a face seal and piston ring is tested and shown to achieve excellent results. A test apparatus is introduced to isolate and measure the spool seal’s performance independent of the compressor. It is concluded that the hybrid design is highly effective and well suited for many applications of the spool compressor.

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An Efficient Immersed Boundary Method For Solving The Unsteady Flow Through Actual Geometries Of Reed Valves, José Luiz Gasche, Franco Barbi, Millena Martins Villar Jul 2012

An Efficient Immersed Boundary Method For Solving The Unsteady Flow Through Actual Geometries Of Reed Valves, José Luiz Gasche, Franco Barbi, Millena Martins Villar

International Compressor Engineering Conference

In refrigeration compressors, the suction and discharge valves are responsible for the retention of the refrigerant from the suction chamber to the cylinder and passage from the cylinder to the discharge chamber. As the opening and closing of the valves are caused by the forces produced by the refrigerant flow, the understanding of the flow through the valve is of fundamental importance in order to enhance the efficiency of the valve system. The numerical simulation of the flow is an efficient method to perform this task. Due to the complex geometry usually found in this type of valve, simplified geometries …

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Parametric Representation Of Scroll Geometry With Variable Wall Thickness, Bryce R. Shaffer, Eckhard A. Groll Jul 2012

Parametric Representation Of Scroll Geometry With Variable Wall Thickness, Bryce R. Shaffer, Eckhard A. Groll

International Compressor Engineering Conference

In a scroll-type compressor, compression is achieved by relative contact between two spiral curves. Since the scroll invention by Leon Creux in (1905) multiple methods have been developed for calculating the scroll geometry and pocket volume. What can generally be considered the most classical method, is defining each scroll curve as the involute of a circle. The two sets of scroll curves are then closed by using the arc of a circle to form the tip of each spiral. In this paper, a new method to calculate the scroll geometry is introduced. By deriving each scroll curve from the radius …

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Numerical Study On The Oil Pump System Of Rotary Compressor, Chunhui Liu, Yuanming Yuan, Yanzhen Wang Jul 2012

Numerical Study On The Oil Pump System Of Rotary Compressor, Chunhui Liu, Yuanming Yuan, Yanzhen Wang

International Compressor Engineering Conference

Oil pump lubrication system is an essential part of compressor to ensure the normal operation. During the process of compressor running, lubricant system can form oil film on surface of moving parts to decrease friction and reduce abrasion and occlusion. In order to meet the lubrication requirements, we must design pump oil structure reasonable. However, oil lubricating and circulating process is a complex and dynamic process, only if through experimental study to understand the characteristics of each components in oil lubrication system is very difficult. Therefore, in this article, we use commercial software CFD to research the best pump structure. …

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Numerical Calculation And Analysis Of Lubricating Water Film Cavitation Of A Water Flooded Air Single Screw Compressor, Rui Huang, Ting Li, Quanke Feng, Weifeng Wu Jul 2012

Numerical Calculation And Analysis Of Lubricating Water Film Cavitation Of A Water Flooded Air Single Screw Compressor, Rui Huang, Ting Li, Quanke Feng, Weifeng Wu

International Compressor Engineering Conference

Reynolds equations and one-phase model with N-S (Navier Stocks) equations are widely used to calculate pressure distribution in the liquid film. In most cases, negative pressure exits in the obtained results. In a water-flooded single screw compressor, it is necessary to investigate the pressure of water film along the whole tooth flank. A negative pressure may not be right, because that when the pressure is lower than the saturated vapor pressure, cavitation occurs. In this paper, we investigated the pressure distribution of the water film with cavitation model. Results were compared to the pressure distribution obtained by one-phase model using …

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The Friction And Wear Characteristic Of Fe-Based P/M Materials In Scroll Compressor, Zhengliang Shi Jul 2012

The Friction And Wear Characteristic Of Fe-Based P/M Materials In Scroll Compressor, Zhengliang Shi

International Compressor Engineering Conference

With the development of materials science and technology, Iron-based powder metallurgy (P/M) antifriction materials gradually used to scroll compressor. In this paper, three kinds of Iron-based powder metallurgy antifriction materials, which are Fe-C-Cu, Fe-C-Cu-Ni-Mo and Fe-P were prepared by the common compacting sintering method. Microstructure and mechanical properties were studied, tribological properties were tested on the friction tester, and surface topographical characteristics and wear mechanism of the Iron-based powder metallurgy materials antifriction were observed and analyzed by scanning electron microscope (SEM). The results showed that, the strength of Fe-C-Cu and Fe-C-Cu-Ni-Mo are higher than Fe-P. The microstructure of Fe-C-Cu and …

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Identification Of Energy Path In The Interaction Between Compressor And Refrigerator, Giovanni Bratti, Otávio Santini Junior, Edmar Baars, Renato Barbieri, Claudio Pellegrini Jul 2012

Identification Of Energy Path In The Interaction Between Compressor And Refrigerator, Giovanni Bratti, Otávio Santini Junior, Edmar Baars, Renato Barbieri, Claudio Pellegrini

International Compressor Engineering Conference

Refrigeration equipments, in particular domestic refrigerators, are devices that are present in our day to day. Often, these devices are very close to our workplaces, laser or rest, where the noise produced by such sources can be intense enough to cause discomforting sensations, fatigue, or even to prejudice the communication between the people. Thus, the concern with the noise produced from these devices has gained a great importance both for consumers and for manufacturers of refrigerators. Thinking in area of control of noise and vibrations, is of great importance the precise knowledge about the dynamic behavior of the components of …

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An Investigation Of Refrigerant Oil Retention In An Air Conditioning System With Two Inverter Compressors In Parallel, Cheng-Shu Kuo, Wei-Yueh Cheng, Wen-Der Hsieh, Yangguang Liu Jul 2012

An Investigation Of Refrigerant Oil Retention In An Air Conditioning System With Two Inverter Compressors In Parallel, Cheng-Shu Kuo, Wei-Yueh Cheng, Wen-Der Hsieh, Yangguang Liu

International Compressor Engineering Conference

A VRF (variable refrigerant flow) air conditioning, having a number of air handling units connected to an external condensing unit, commonly uses two or more compressors in the system. The complicated piping system of the VRF air conditioning causes difficulties for refrigerant oils to return back to each compressor, especially for compressors operating in different frequencies. Compressors need lubrication in operation process, otherwise the compressor will burn out because of wearing and overheating. Therefore, whether refrigerant oils can successfully return back to each compressor has become a key issue in the VRF air conditioning system. To this regard, this report …

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Research Of R290 Compressor Effect On Rac System Charge Amount, Bin Gao, Zhenhua Chen, Qiang Gao Jul 2012

Research Of R290 Compressor Effect On Rac System Charge Amount, Bin Gao, Zhenhua Chen, Qiang Gao

International Compressor Engineering Conference

During the process of refrigerant alternative, R290 (propane), as a nature refrigerant used in Room Air Condition (RAC) system, is thought as a long-team substance and has attracted great attention. This paper simply introduced the characteristics and standard demands of R290 application, then, based on a 1HP R290 DC INV. RAC system at first, then finished the comparison test when a one-cylinder and a two-cylinder rotary compressor was matched, in addition, deeply analyzed the connection between RAC system performance and refrigerant charge amount according to the test results. Lastly, comprehensive consideration of the refrigerant charge amount, analyzed the different demands …

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