• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.2
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• pp.134-143
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• 2001

This paper presents the characteristics of flank and tip seal leakage in a scroll compressor for air-conditioners with R-22 under actual operating conditions. It is well known that the leakage has significant effect on the performance of the scroll compressor. Experiments were performed by using indirect method for measuring mass flow rate passing through flank and tip seal under actual operating conditions, In addition, an analytical model for tip seal leakage was developed to investigate tangential and radial leakage observed at grooves and contact points of tip seals. For low oil concentration, theoretical results were compared with experimental data to verify the analytical model. As a result, leakages through flank and tip seal parts were evaluated as afunction of pressure ratio, orbiting angle, discharge pressure, tip clearance, and leakage point. It was also found that the tip seal leakage was considerable even though the tip seal provided adequate sealing effect.

• 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.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.5
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• pp.377-387
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• 2001

This paper presents leakage characteristics of a scroll compressor applying alternative refrigerants of R22 such as R407c and R410a under actual operating conditions. Because leakage in a scroll compressor produce significant losses and degradation of performance, those should be clarified to design a high efficient scroll compressor with alternative refrigerants of R22. However, flank and tip leakage characteristics of a scroll compressor with alternative refrigerants are very limited in open literature. In the present study, both experimentation and modeling of the leakages in the scroll compressor were performed. As a result, it was observed that the leakages of the scroll compressor with R407c increased by 15%, and that with R410a increased by 76% as compared to the compressor applying R22 under standard load conditions due to a higher upstream pressure and a higher pressure difference between pockets.

• Tribology and Lubricants
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• v.30 no.6
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• pp.370-377
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• 2014

The basic elements in a rotary-type scroll compressor are two identical spiral scrolls containing refrigerant gas. The pressure variations in the compression pockets of a scroll compressor change the forces acting on the orbiting scroll, and these forces affect the dynamic behavior of the compression mechanism parts. To achieve high efficiency, using a self-sealing mechanism as a tip seal mechanism is very effective. Tip seals, which are placed on top of the scroll wraps, accomplish thrust sealing. This study calculates the friction force between the tip seal and the side plate of a scroll compressor using the numerical model considered in the Reynolds equation. The calculated friction force is verified by an experiment using a pin-on-disk apparatus. A hydraulic servo valve that controls the pressure of the oil hydraulic cylinder applies the normal load for the test, and a DC servo motor controls the sliding velocity of the disk. The friction force and normal load are measured by the force sensors attached to the supporting parts. The results show that the theoretical and experimental results are similar and that the friction is influenced by the viscosity of the oil and the sliding velocity of the scroll.