Study on speed of sound in hydraulic oil in a hydraulic pipe

Abstract

Recently, the choice of power sources in industrial vehicles has tended to shift from internal combustion engines to electric motors. Consequently, contribution of noise emitted from a hydraulic system is becoming relatively prominent. It is, therefore, more than ever important to take care of the hydraulic noise in the industrial vehicles. It is known that speed of sound in hydraulic oil has an effect on pressure ripples which can be source of the noise. Therefore, it is important to understand behavior of the speed of sound reasonably in design of quiet hydraulic systems. However, relationship between operating conditions and the speed of sound has not been revealed up to now. In this study, the speed of sound has been investigated at the operating conditions for typical agricultural machines and construction machinery.