Abstract
Fluid power systems and components become more complex and sophisticated. Although great efforts have been made to make hydraulic components quieter, noise and vibration problems are major and growing drawbacks of fluid power systems.
A variety of methods to measure the oscillary flow from a fluid power pump have been proposed during the last decades. This paper is concerned with the “anechoic termination” method. A mathematical model is proposed in order to control the errors introduced by the actual device used to achieve anechoic conditions. Results from measurements on pump flow ripple using this method are presented.
The noise and vibration problems can be considerably reduced by means of a fluid power attenuator. A very simple one, the one-chamber expansion chamber attenuator, is studied in this paper.
Standing wave phenomena due to the chamber itself are carefully penetrated. It is also shown how to improve the attenuation by means of a mode cancellation pipe. In both cases simulations and measurements are carried out and the agreement is generally fairly good.
