• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.8
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• pp.648-655
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• 2002

For a discharge system of rotary compressor, analytical investigation on the discharge gas pulsation has been carried out. With the aid of four pole theory, acoustic impedance of the discharge system composed of muffler and cavities on both sides of motor with gas passages between them can be calculated using discrete acoustic elements described by transfer matrices, yielding the relationship between discharge mass flow rate and gas pulsation at the discharge port. This method of predicting the gas pulsation was validated by measurement data. Effects of change in discharge muffler geometries on the gas pulsation also were investigated, demonstrating that this method can be used for muffler design.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.697-703
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• 2003

For a single stage two cylinder rotary compressor, an analytical study has been made on the discharge gas pulsation. Discharge system of the twin rotary compressor consists of lower and upper mufflers and connecting passage holes between them, and cavities on both sides of the motor and passages between them. Acoustic modeling for the discharge system by transfer matrix method gives acoustic impedances at discharge valves so that gas pulsation at the valve sections can be obtained from discharge mass velocity. Since the mass velocity and the pressure pulsation at the valves are affected by each other, iteration should be made for convergence. Gas pulsations at other sections can also be calculated by using transfer matrix.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1995.06b
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• pp.14-20
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• 1995

본 연구에서는 압축기내의 이상류, 즉 냉매와 오일의 혼합상태라 하는 특수한 환경에서 하중을 지지하고 있는 상하부 베어링에서의 윤활특성파악을 위하여, 압축기의 동역학해석 및 레이놀즈방정식을 이용, 베어링의 축심궤적을 수치해석에 의해 결정하고, 여러 운전조건에서 축심궤적의 변화를 살펴 보았다. 또한, 실험에서는 실제의 냉방시스템에 사용되고 있는 로터리 압축기의 축심궤적을 갭-센서를 이용하여 파악, 그 결과를 나타냈다.

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.136-136
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• 2004

• The KSFM Journal of Fluid Machinery
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• v.11 no.2
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• pp.29-37
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• 2008

Air supply is required to the cathode of fuel cells for the provision of oxygen to produce electricity through chemical reaction with hydrogen in the cell, and supplied air should be free of impurities such as oil mist and tiny particles separated from sliding surfaces. Hence, air compressor for fuel cell air supply must be oil-less type and have no severe sliding surfaces inside. This paper introduces the concept of single-vane type rotary air compressor whose structure is particularly suitable for the fuel cell application: sliding action of the vane against the cylinder wall, which causes severe friction in the conventional vane rotary compressors, is made to be prevented by attaching the vane to the driving shaft with the compliant device between the vane and the rotor in this new design. For 2 kW fuel cell application, preliminary design has been carried out, and its performance has been estimated by using computer simulation program: for discharge pressure of 2 bar, the volumetric, adiabatic, and mechanical efficiencies are calculated to be 82.5%, 92.5%, and 96.3%, respectively.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.904-909
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• 2009

In this paper, a rolling piston rotary compressor having a combined vane and roller unit has been introduced. In a conventional rotary compressor, sliding motion takes place between the vane nose and roller. By combining the vane and the roller in one unit, gas leakage through a clearance between the vane nose and the roller can be eliminated, and the frictional loss between them can also be reduced to almost nought. Compressor model with the combined vane and roller has been fabricated and tested in a compressor calorimeter and computer simulation program has been developed to confirm merits of the new mechanism. In a test, cooling capacity has been found to be increased by 1.4%, and the compressor input decreased by 0.3%, resulting in 1.7% increased in EER. Simulation program confirmed the calorimeter test results and the merits of the new model as mentioned above.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.8
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• pp.549-555
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• 2011

For a $CO_2$ one-stage twin rotary compressor, a T-shaped suction port was used to effectively supply the suction gas stream into two individual suction chambers of the twin cylinders. Suction gas pulsations were observed in the pressure sensor signals and these were simulated by using the acoustic modeling of Helmholz resonators in parallel. The module of acoustic modeling was combined to a computer simulation program for the compressor performance. Validation of the simulation program has been carried out for a bench model compressor in a compressor calorimeter. Cooling capacity and the compressor input power were reasonably well compared between the simulation and the calorimeter test. Particularly, good agreement on P-V diagram between the simulation and the test was obtained.

• Proceedings of the SAREK Conference
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• 2007.06a
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• pp.4-4
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• 2007

• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.123-123
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• 2003

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.137-137
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• 2004