• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1437-1443
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• 2000

왕복동식 압축기에서 고효율 토출밸브를 개발하였다. 멈치개(stopper)가 있는 외팔보 형태의 토출 밸브는 밸브 및 멈치개의 형상과, 밸브와 멈치개 및 밸브시트에 존재하는 오일에 의한 점성력(sticky force) 등에 의한 밸브의 개폐과정과 동적 거동특성의 변화를 유발한다. 본 논문에서는 오일막에 의한 점성력을 측정하고, 그에 의하여 유발되는 지연시간(time-lag)을 측정할 수 있는 실험장치를 개발하였다. 또한, 토출밸브의 개폐과정을 최적화하여, 과압축 손실을 최소화한 토출밸브계를 개발하였다. 개발된 밸브계에 대하여 실험적인 방법으로 그 효과를 검증하였다.

• The KSFM Journal of Fluid Machinery
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• v.9 no.2 s.35
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• pp.13-18
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• 2006

This paper was studied to design Process considered flexibility and reliability of suction and discharge valves. Flexibility and reliability of valves are main important factors in compressor valves design. And they are incompatible with efficiency of compressor. In this study, we have performed the optimal design of CO2 compressor valves to consider these factors. At first, we analyzed performance simulation of compressor to obtain optimal flexibility level of valves. From this simulation, we could get some important data at valve design like the optimal natural frequency and the height of retainer. After that we studied to reliability of valves corresponding to optimal flexibility level by finite element method. For each case bending stress and natural frequency were obtained by it. Also we investigated the fatigue stability to obtain optimal valve shape that ensured to reliability.

• Journal of KSNVE
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• v.10 no.4
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• pp.615-622
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• 2000

Discharge valve mechanism for an electrodynamic-oscillating compressor is different from that of a conventional reciprocating compressor. It has a larger discharge port area, heavier valve mass and stiffer valve spring comparing with the reciprocating one. Since the motion of piston is not kinematically restricted as in conventional reciprocating compressors, the stroke of the piston can change sensitively with supplied boltage and load. Thus piston can impact with discharge valve occasionally. This work deals on dynamic analysis of discharge valve considering all of those different characteristics. Impact is considered by a spring-mass model, and the pressure fluctuation at the both sides of the valve is also included considering the discharge port area and valve spring preload. It is assumed that piston moves in the region of between top and bottom dead center not by calculating piston motion from an electrodynamic equation but by getting values through experiment. Discharge pressure fluctuation is calculated using Helmholtz modeling. Finally, dynamic model for a discharge valve is constructed. In order to validate the model analysis results, the valve motion is experimentally measured and compared with analysis.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.12
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• pp.1237-1243
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• 2009

A computational procedure to estimate the noise radiated from a discharge valve system in a linear compressor was discussed and established. This procedure was composed of three steps. As the first step, the dynamic behavior of the valve system was estimated taking into consideration of fluid-valve-piston interactions. As the second step, the flow characteristics of refrigerant in the discharge valve system were estimated through computational fluid dynamics applying the behaviors of the valves as moving boundary conditions. The variations of pressures and velocities of fluid were converted to quadrupole noise sources. As the final step, the boundary element method based on Helmholtz equation was applied to predict the radiated acoustic pressure. The computational results by the presented procedure were experimentally validated.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.5
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• pp.112-120
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• 2008

This study has been conducted to investigate the characteristics of flow field and discharge valve motion in a rotary compressor. In this study, a transient three-dimensional numerical analysis using FSI(Fluid-Structure Interaction) model has been employed to analyze the interaction between the discharge valve and the refrigerants in the rotary compressor. It has been observed that two peaks have appeared in the displacement of the discharge valve. The maximum displacement of the discharge valve has been found to be located at the second peak. Also, the input pressure of the refrigerants has been compared with the pressures of the muffler passage and the compressor outlet in the rotary compressor. The pressure has decreased along the pathway in the rotary compressor. And the volume flow rates obtained from the current numerical study have been compared with the experiment at data to verify the validity of the present numerical study. This study may supply the fundamental data for the design of rotary compressors.

• The Safety technology
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• no.109
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• pp.68-70
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• 2007

• The KSFM Journal of Fluid Machinery
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• v.8 no.4 s.31
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• pp.61-65
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• 2005

• Proceedings of the KIEE Conference
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• 2008.10c
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• pp.117-119
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• 2008

본 논문은 부스터펌프 자동제어시스템의 성능평가를 위한 시험방법에 관한 것이다. 본 논문에서 제안하는 시험방법은 펌프 자체의 성능평가에만 의존했던 기존의 방법과 달리 펌프와 펌프를 제어하기 위한 자동제어장치까지 포함한 전체 시스템에 대한 성능평가를 할 수 있도록 한다. 본 시험방법은 부스터펌프 자동제어시스템을 설치하고, 토출 측에 전자제어밸브를 설치하여 이를 제어함으로써 물의 사용량 즉, 유량에 변화를 주게 된다. 이때 토출압력을 일정하게 유지하도록 설정된 자동제어시스템은 펌프를 제어하여 물을 토출 측으로 공급하게 되며 이를 통해 토출압력의 변화를 측정하는 방법이다. 이러한 시험방법에 있어서 정상상태특성시험, 가속 특성시험, 응답특성시험을 수행한다. 결과적으로 본 논문의 시험방법을 통해 전체 시스템에 대한 성능평가가 가능하며, 모든 시험과정을 자동화 할 수 있고 다양한 운전환경에 대한 유량변화를 짧은 시간 내에 적용하여 시험에 소요되는 시간을 단축할 수 있다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.7
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• pp.1087-1094
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• 2003

The piston slap phenomenon occurs when the piston collides with the internal wall of the cylinder. Impact force caused by piston slap is one of the major mechanical noise sources in reciprocating compressors. In response to public demand, strict regulations are increasingly being imposed on the allowable noise level which is caused mostly by household electric appliances. In this paper, forces acting on piston by considering the dynamic behavior of suction and discharge valves are analytically calculated and the piston slap caused by the piston secondary motion is investigated by the finite element method.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.768-770
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• 2014

A shaft of a reciprocating compressor receives bending force by piston, which makes movement of the shaft. The movement of the shaft affects durability and becomes a source of noise. In this paper, a cylinder is modeled by considering motion of a suction and discharge valve. The journal bearing is modeled by Bernoulli's equation. The trajectory of shaft which is considered cylinder and journal bearing can be calculated by finite element method. It will help a design of shaft to increase durability and reduce noise.