Active multi-port characterization of a butterfly valve

In many applications, a flow duct system is one of the main transmission paths for noise generated by fans, engines,. Within the duct network, different components such as bends, junctions, valves, etc. transmit and reflect the incoming noise and can act as an additional source of aerodynamically generated sound. For a proper aeroacoustic design of such duct systems, network modelling tools are commonly used. These tools rely on individual models for the duct components, describing the passive and active aeroacoustic properties independent of the upstream and downstream components. These models are typically based on the twoport characterization formalism, where the passive and active aeroacoustic properties of the component are described by, respectively, the scatter matrix and the active source vector. However, because of the underlying assumption of plane wave propagation, this approach is only valid at low frequencies, below the first cut-off frequency of the duct. To overcome this frequency restriction, this paper uses the multi-port characterization technique. This is an extension of the formalism to higher frequencies, taking into account the limited set of cut-on modes in the ducts. In this paper, the active multi-port characterization procedure is applied to an industrial butterfly valve from an aircraft environmental control system.

ISBN:9789073802940

Jaar van publicatie:2016

BOF-keylabel:ja

IOF-keylabel:ja

Authors from:Government, Higher Education

Toegankelijkheid:Closed