An experimental methodology and test facility has been developed to perform measurements of internal sound pressure radiated from expansion devices in refrigerant. The experimental test facility is designed to help attenuate reflected sound waves and minimize both vibrations to the test section and other flow disturbances. Measurements are made using microphones mounted flush to the inner wall of the refrigerant tube and the two-microphone technique is used to account for unattenuated reflections. Results show that expansion noise is related to system operating conditions. When vapor flow is present, the far field expansion noise is significant white noise over the audible frequency range. Downstream screens were found to significantly reduce the noise generated. Also, internal sound pressure attenuation with distance has been measured and the results agree closely with theoretical predictions for visco-thermal attenuation.
Noise Generation from Expansion Devices in Refrigerant
Sae Technical Papers
International Off-Highway & Powerplant Congress & Exposition ; 1999
1999-03-01
Conference paper
English
Noise Generation from Expansion Devices in Refrigerant
British Library Conference Proceedings | 1999
|Noise generation from expansion devices in refrigerant
Automotive engineering | 1999
|Refrigerant expansion noise propagation through downstream tube walls
Automotive engineering | 1999
|Refrigerant Expansion Noise Propagation Through Downstream Tube Walls
SAE Technical Papers | 1999
|1D Modeling of Thermal Expansion Valve for the Assessment of Refrigerant-Induced Noise
SAE Technical Papers | 2016
|