Studies on Reed Valve Using PIV and Valve Displacement Measurements in a Reciprocating Compressor for an Automotive Air-Conditioner

The simplified test model of the commercial reciprocating compressor for an automotive air-conditioner is used to measure the displacement of the suction valves using a strain gauge and to investigate the velocity distributions of the discharge flow from the valves using the particle image velocimetry system. This paper is focused on the effects of shape of the suction valve on the vibration-reduction. The size of the suction valve hole and the width of the tip of the suction valve are changed as main parameters of the valve shape. First, the size of the conventional valve hole and the width of the tip of the conventional valve are changed and seven new valves are manufactured to reduce the vibration of the valve. Consequently, it is found that one shape of the new valves is the most effective for the vibration-reduction. Next, the influence of the natural frequency on the vibration-reduction is investigated using one shape of the new valves by changing the material and the thickness of the valve. In addition, the relation between the conventional valve and the new valves are also estimated by the pressure loss. Finally, the reason of the vibration-reduction for one shape of the new valves is discussed from the results of the flow analysis around the valve. The vibration-reduction for one shape of the new valves is confirmed by measurement of the displacement of the valve in the reciprocating compressor for the automotive air-conditioner.

Download Full-text

Reliability design of a reciprocating compressor suction reed valve in a common refrigerator subjected to repetitive pressure loads

Engineering Failure Analysis ◽

10.1016/j.engfailanal.2009.12.001 ◽

2010 ◽

Vol 17 (4) ◽

pp. 979-991 ◽

Cited By ~ 19

Author(s):

Seong-woo Woo ◽

Dennis L. O’Neal ◽

Michael Pecht

Keyword(s):

Reciprocating Compressor ◽

Reliability Design ◽

Reed Valve

Download Full-text

Effect of Oil on the Dynamics of Compressor Suction Valve

Volume 1C: 16th Biennial Conference on Mechanical Vibration and Noise ◽

10.1115/detc97/vib-4029 ◽

1997 ◽

Author(s):

H. Ezzat Khalifa ◽

Xin Liu

Keyword(s):

Relative Effect ◽

Viscous Force ◽

Reciprocating Compressor ◽

Cylinder Pressure ◽

Oil Viscosity ◽

Valve Seat ◽

Rapid Release ◽

Valve Stiction ◽

Valve Opening ◽

Reed Valve

Abstract The presence of oil on the suction valve of a reciprocating compressor has long been known to be responsible for the so-called valve stiction phenomenon. With stiction, the opening of the valve is delayed until later in the suction stroke, which results in a reduction in volumetric efficiency and increases the probability of valve failure. In this paper, a model is presented for analyzing the dynamic behavior of a round reed valve in the presence of oil. It is shown that the primary reason for stiction is the viscous force arising from dilating the oil film between the valve and its seat. This dilation takes place as the cylinder pressure on one side of the valve reed falls below the suction pressure in the intake plenum upstream of the valve. The viscous force delays the valve opening until later in the suction stroke. Because the film dilation resistance is directly proportional to the oil viscosity and decreases rapidly as the film thickens, the film eventually breaks and the valve begins to accelerate rapidly until it impacts the valve stop. The delayed rapid release of the valve and the associated impact are shown to subject the valve to much higher forces than would be experienced without the effect of stiction. The relative effect of oil viscosity and valve/seat contact area on valve force is presented for a representative reciprocating compressor equipped with suction valves.

Download Full-text