Study on Noise from Air-Cooled Heat Exchanger by Compressor Pulsation

摘要

Noise problems caused by gas pulsations in the tubes of air-cooled heat exchangers have become more serious with the advance of the techniques for fan noise reduction in air conditioners. The prediction and the reduction of noise caused by the gas pulsations were investigated. The predictions of sound radiation and tube vibrations of air-cooled heat excliangers were carried out. using Statistical Energy Analysis (SEA). The value of the loss factor of gas pulsations becomes high, when two-phase flows occur in the tubes. Therefore, the values were investigated and used for prediction. For the exciting forces, the forces of pressure at U bends and in straight pipes of heat exchangers were used. Air conditioners developed using the above method generate very low noise levels and they have been well received by customers.