Investigation of the Mass Flow Sources in a Multi-Cylinder Compressor Using Frequency Response of Pressure Pulsations in the Suction Manifold

Linear acoustic plane wave theory and a four pole parameter formulation are used to derive and solve the governing inhomogeneous equation for the forced pressure response in the simplified manifold model. The equations for estimating gas pressure pulsations in the annular cavity connected to an anechoic inlet pipe are presented. Complicated interactions between multiple cylinder valve ports in the suction manifold produce unexpected changes in the frequency response conditions for changes in the operating speed, and hence, the flow rate characteristics through the valves. From the addition of the delayed time for opening valve in the mass flow rate profiles and the comparison of the gas pulsations from experiment with those from simulation, the maximum strokes of the piston and the delayed times for opening valve can be estimated without solving the valve dynamic and thermodynamic equations. By applying the mass flow rate sinks at each valve as identified, the correlation between analytical and experimental results is shown to be much better than if the idealized, kinematically obtained source functions are used instead.

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Numerical Studies on Frequency Response to Mass Flow Rate Variations in a Hydromechanical Pulsator

45th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit ◽

10.2514/6.2009-4956 ◽

2009 ◽

Cited By ~ 2

Author(s):

Madhanabharatam Balasubramanyam ◽

David Lineberry ◽

Chien Chen ◽

Vladimir Bazarov

Keyword(s):

Frequency Response ◽

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Numerical Studies

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Gas Pulsation Reductions in a Multicylinder Compressor Suction Manifold Using Valve-to-Valve Mass Flow Rate Phase Shifts

Journal of Vibration and Acoustics ◽

10.1115/1.2748457 ◽

2007 ◽

Vol 129 (4) ◽

pp. 406-416 ◽

Cited By ~ 8

Author(s):

Jeong-Il Park ◽

Nasir Bilal ◽

Douglas E. Adams

Keyword(s):

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Beam Equation ◽

Pressure Pulsations ◽

Flow Rates ◽

Calculated Mass ◽

Mass Flow Rates ◽

Linear Differential ◽

Cylinder Method

This paper investigates the pressure pulsations caused by each mass flow rate through the suction valves and ports of a multicylinder compressor in order to attribute high-pressure pulsation responses to certain valves. By staggering the valve configurations appropriately, it is shown that the level of gas pulsations in the suction manifold of a multicylinder automotive compressor can be reduced. First, the equation for a compression cycle, a Bernoulli-Euler linear differential beam equation for the suction valves, and the piston kinematics are considered in order to calculate the mass flow rates through the compressor suction valves. The pressure pulsations in the suction manifold are then predicted based on the characteristic cylinder method using the calculated mass flow rates. In order to investigate the effects of each mass flow rate, the characteristics and phases of the mass flow rates through the suction valves are changed by modifying the clearance volume.

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Numerical and Experimental Studies of Gas Pulsations in the Suction Manifold of a Multicylinder Automotive Compressor

Journal of Vibration and Acoustics ◽

10.1115/1.2732352 ◽

2008 ◽

Vol 130 (1) ◽

Cited By ~ 3

Author(s):

Jeong-Il Park ◽

Nasir Bilal ◽

Douglas E. Adams ◽

Yoshinobu Ichikawa ◽

Jacob Bayyouk

Keyword(s):

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Experimental Studies ◽

Beam Equation ◽

Discharge Process ◽

Simulation Code ◽

Calculated Mass ◽

Linear Differential ◽

Gas Pulsations

This study predicts gas pulsations in the suction manifold of a multicylinder automotive air-conditioning compressor using a comprehensive simulation model of a reciprocating compressor. On the basis of the first law of thermodynamics and a simplified fourth-order Bernoulli-Euler linear differential beam equation for suction valves, the pressure in a cylinder and resultant pressure pulsation in the suction manifold are predicted. The mass flow rate through the valve is estimated assuming one-dimensional compressible flow through an orifice. All of the equations are then solved together in a sequence to obtain the pressure in the cylinder, valve response, and the mass flow rate. A complicated suction manifold geometry is modeled as a simplified cylindrical annular cavity to study gas pulsations in a multicylinder compressor, but the discharge process has not been considered in this study. Using the calculated mass flow rate, pressure pulsations in a simplified cylindrical annular cavity with an area change to consider “mode splitting” are predicted based on the characteristic cylinder method. It is shown that the simulation code can be a useful tool for predicting gas pulsations in the suction manifold of a multicylinder automotive compressor.

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