The Use of an Equivalent Forces Method for the Experimental Quantification of Structural Sound Transmission in Ships

One-Dimensional Fluid–Structure Interaction Models in Pressurized Fluid-Filled Pipes: A Review

“…[165] suggested that, for the full description of sound generation in pipe-systems, seven degrees-of-freedom are required. This statement was verified in [166]. A pump-induced fluid-borne noise investigation is carried out by [167] by means of a distributed-parameter transfer-matrix model in the frequency-domain.…”

Broadband characterisation of in-duct acoustic sources using an equivalent source approach

“…A requirement of the proposed inverse approach is the existence of a reliable phase relationship between the elements of the operational pressure vector, p = [p 1 , p 2 , • • • , p n ] T . Classically, in both acoustic and vibro-acoustic applications, this type of operational vector is determined from time averaged auto and cross-spectra, where the crossspectrum angle between each signal and a reference is assigned as the phase of the appropriate auto-spectrum [31] where, and < > represent the Hadamard (element-wise) product and time averaged quantities, respectively. Although a well established method, this cross-spectrum phase approach not only relies on a constant phase relationship, but assumes a steady state source behaviour.…”

Coupled vibration characteristics of a submarine propeller-shaft-hull system at low frequency

“…35,36 For ships or submarines, TPA studies were triggered by the need to reduce the transmission of engine vibrations in order to make them stealthy. Most of the publications are focused on isolation of ship diesel engines or gas turbines by means of absorbers and decoupling mechanisms 37,38 to minimize the transmission through the interfaces. Few papers discussed about the transfer path for propeller excitation, such as Feng et al 39 established a propulsion shaft model and analyzed the transfer path for longitudinal excitation using the power flow method.…”