31.10.2018

SIMVEC - Simulation and Testing in Vehicle Development

Dr. Baum talks about the "Consideration of the acoustic behavior of complex components in the simulative pressure oscillation analysis" on November 21, 2018 on the 19th VDI Congress SIMVEC in Baden Baden.
In automotive fluid power systems pressure oscillations are quite common, which are the cause of problems and complaints. It thereby does not matter whether it is a hydraulic or pneumatic system. Classic hydraulic examples are braking systems, clutch actuations and power steering as well as the entire framework of the fuel supply or the SCR system of ex-haust aftertreatment. Examples of pneumatic systems are the air-conditioning channels, the gasoline vapor extraction of the fuel tank or the exhaust system. In principle, all fluid-technical systems in which components are connected via pipes and hoses.
More complex components of these systems usually consist of a sequence of branched channels and volumes, whose material behavior may also change depending on the pressure or temperature. The analytical description of the acoustic behavior (impedance) of these components is difficult and can only be done very laboriously by means of physical simulation models.
In this paper, an alternative approach is presented, in which the component impedance is rep-resented by a replacement model whose parameters are determined from processed meas-urement data. For this purpose, a measuring method is used, with which the impedance of any hydraulic and pneumatic components can be measured at short notice.