• The KSFM Journal of Fluid Machinery
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• v.15 no.6
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• pp.51-57
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• 2012

Performance evaluation of a compressor is conducted to develop 500W class ultra-micro gas turbine (UMGT) for power generation. The performance evaluation is essential to check the performance of the components of UMGT, a radial turbine, a centrifugal compressor, an angular combustor and a shaft, which have been already designed in previous researches. The purpose of this study is to introduce the development process of the performance testing equipments of the UMGT and to present the results of compressor performance test. For the performance evaluation of the compressor, two test equipments are developed and the initial test equipment uses commercial static air bearings with long shaft. In the improved test equipment, static air bearing is improved to increase rotating speed and compressed nitrogen gas is used for utility gas of the static air bearing to supply compressed air in a stable and steady way. To increase rotating speed to 320,000 rpm, 80% speed of design speed, compressed air is provided to the turbine. The performance map of the compressor with the 50%, 60%, 70%, 80% speed of design point is presented. The results of the performance test of compressor show a good agreement with the results of 3D CFD.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.12
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• pp.1306-1318
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• 2001

This paper presents leakage and performance characteristics of a tip-seal type scroll compressor, The performance of a scroll compressor is strongly dependent on the leak age across the compression pockets. However, literature for leakage characteristics of the tip seal type scroll compressor is very limited due to complex sealing mechanism. In the present study, a simulation study was executed to investigate the tip-seal type scroll compressor by considering leakages passing through flank and tip clearance. As a result, the leakage phenomena of the tip seal type scroll compressor as a function of discharge pressure, tip clearance, dimension of the tip seal were analyzed. Effects of leakage on the performance of the compressor were also clarified.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.215-220
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• 2002

This paper describes a simulation model for estimation the performance of the swash plate type compressor for automotive air conditioning system. The model includes consideration of both the compression process and the dynamic behavior. Also, this study compares the results obtained from the performance simulation with experimental results. Further, the effects of the inclined angle of swash plate on the performance of swash plate type compressor are discussed.

• The KSFM Journal of Fluid Machinery
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• v.6 no.3 s.20
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• pp.36-43
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• 2003

Operating performance of industrial gas turbines in combined cycle power plants depends upon atmospheric conditions. Compressor fouling caused by airborne particles in the atmosphere and their adhesions on compressor blades is one of critical phenomena related to the performance degradation of industrial gas turbines. Compressor fouling provokes increase of pressure loss in inlet duct, decrease of mass flow rate of intake air and decrease of compressor stage efficiency. In this study, impacts of compressor fouling on the performance of an industrial gas turbine operating at design point condition are investigated analytically. As results, it is found that the reduction of produced power with decreased mass flow rate of intake air caused by narrowed flow area by the adhesion of airborne particles on compressor blades is the most dominant impact on the gas turbine performance by the compressor fouling phenomena.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.8
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• pp.1964-1971
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• 1995

In the present study, the performance characteristics of a centrifugal air compressor were investigated experimentally. The PC controlled performance test facility for a centrifugal air compressor driven by an electric motor with a gear box to achieve higher compressor rotating speed was set up in the present study. The performance test for a turbocharger compressor of a diesel engine was conducted, and in a case of 34,800 rpm, pressure ratio 1.18, flow rate 0.09kg/s, compressor efficiency 61% were investigated. Adiabatic power for a tested compressor showed maximum value at mass flow ratio 0.8. The value of mass flow ratio of maximum efficiency was about 0.37, it was independent of compressor rotating speed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.1
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• pp.77-84
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• 2012

Numerical performance analysis of the vane-roller integral type swing compressor was conducted. The swing compressor has been investigated for the highly efficient air conditioning system. Performance analysis results of the swing compressor were compared with those of a conventional rotary compressor. Mechanical and gas losses of a swing compressor were larger than those of a rotary compressor. However in case of mass flow rate from the discharge port, the swing compressor was about 6.68% higher than the rotary compressor. Hence the EER, the cooling capacity and the compressor work of the swing compressor were about 3.71%, 6.69% and 2.90% higher than the rotary compressor respectively.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.572-577
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• 2006

Numerical simulation has been made on the performance of an oil free air compressor for automotive electronic air suspension system. Calculation results on the flow rate at various air supply pressures were reasonably well compared to the experimental data. With the aid of the computer simulation program, parametric study on the compressor design parameters has also been carried out for the compressor performance improvement: Increase in the discharge port diameter or discharge valve stiffness was found to be effective to increase the flow rate per unit compressor input for the present compressor model.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.5
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• pp.448-456
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• 2000

For piping line systems associated with a double-acting reciprocating compressor, an analytical study has been made on the gas pulsation in piping lines and its effects on the compressor performance. The transfer matrix which relates mass flow rate to the gas pulsation downstream of the compressor valve can be obtained by an acoustic model for piping line systems which include snubber and after-cooler with the aid of four pole theory Since mass flow rate is affected by the pressure pulsation in the pressure plenum, while the latter being determined by the former, iteration in the calculation should be made for convergence. The gas pulsation in pipings is found to have an adverse effect on the compressor's performance, and the magnitude of the gas pulsation can be lowered by increasing snubber volume.

• Progress in Superconductivity and Cryogenics
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• v.4 no.2
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• pp.58-62
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• 2002

The purpose of this study is to analyze the charging gas effect on the resonance and performance characteristics of the linear compressor for small scale FPFD Stirling refrigerator. To ensure high performance of FPFD type Stirling refrigerator, the operating frequency of the refrigerator should be around the natural frequency of compressor. The gas spring effect which is induced from Pressure change in cylinder due to motion of pistons has significant effect on the natural frequency of the compressor. The numerical results show the linear compressor has high natural frequency when the charging pressure of working fluid is high and the stroke of compressor, current, input power and efficiency of compressor were shown with different operating conditions.

• The KSFM Journal of Fluid Machinery
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• v.8 no.1 s.28
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• pp.7-15
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• 2005

Tip clearance of centrifugal compressor affects the performance. Larger tip clearance results in lower efficiency. What really affects the performance is the running tip clearance, not the cold tip clearance. When the compressor is operating, blade strain and the pressure difference between impeller backplate and hub affects the running tip clearance. This paper describes measured running tip clearance and its effects on the performance of centrifugal compressor. Cold tip clearance before operation was 0.4 mm and running tip clearance varied from 0.86 mm to 0.25 mm with impeller exit pressure. As the pressure at impeller exit increases, the running tip clearance tends to decreases. The target running tip clearance for Compressor at $100\%$ speed was 0.3 mm, and it turned out to be exactly 0.30 mm from experiment.