Hydraulic System Noise Attenuators for Aircraft Application: Study of a “Disc-Silencer” Design

Fachgebiet:

Hydraulische Energieversorgung

Jahr:

2014

Art der Publikation:

Paper

Schlagworte:

Aircraft Hydraulic System, Hydraulic System Noise, Fluid-Borne Noise FBN, Dampers, Attenuators, Expansion Chambers, Inline-Silencer, Lumped Parameter Modeling, Impedance Modeling

Autoren:

Arne Waitschat, F. Thielecke, C. Nisters, P. Kloft, U. Heise, R. M. Behr

Buchtitel:

International Conference on Recent Advances in Aerospace Actuation Systems and Components (R3ASC’14)

The objective is to achieve low noise aircraft hydraulic systems while the size/weight and complexity of required modifications is kept to a minimum. A low overall noise characteristic is supposed to increase aircraft durability and passenger comfort. The characteristic is strongly affected by the flow and pressure ripple in the hydraulic system, especially in the pump high pressure line. Ripple attenuation devices are typically applied here close to the pump, which is considered as main ripple source. In order to set up a hydraulic circuit with low noise characteristics, two general aspects have to be considered: Means of prediction for the system characteristics and the design of innovative devices for noise reduction. Here, the design of a device named “Disc-Silencer” is addressed. This new device is based on state-of-the-art aircraft inline silencers in their most simple version of a single expansion chamber. Those usually represent a change of diameter compared to the connected piping. The cross-sectional area keeps circular but increases in two dimensions; width and height. In case of the “Disc-Silencer” only one dimension is extended while the other one keeps identical to the piping diameter. In this paper a laboratory prototype and first test results are shown. Furthermore, an approach of modeling the device for system pre-design purposes is discussed.