Vibration-Induced Pressures on a Cylindrical Structure Surface in Compressible Fluid

Abstract

This paper unprecedentedly addresses the effect of vibrations of a cylindrical structure on dynamic pressures in a compressible and incompressible fluid situation. To obtain analytical solutions, the density of the fluid is simplified as a constant, but the rates of the density with respect to time and to space are considered as a dynamic and time-dependent function. In addition, the low velocity of the vibration is taken into account so the lower order terms are negligible. According to the assumption that the vibration at the boundary of the structure behaves as a harmonic function, some interesting and new analytical solutions can be established. Both analytical solutions in the cases of the compressible and incompressible fluid are rigorously verified by the calibrated numerical simulations. New findings reveal that, in the case of the incompressible fluid, dynamic pressure at the surface of the cylindrical shell is proportional to the acceleration of the vibration, which acts like an added mass. In the case of the compressible fluid, the pressure at the surface of the cylindrical structure is proportional to the velocity of the vibration, which acts as a damping. In addition, the proportional ratio is derived as ρ c .

Theoretical and Experimental Study on Rapid Decompression Oscillation in Altitude Chamber

“…Chambers. The optimal ratio of the effective volume of the altitude chamber to the volume of the vacuum chamber, which is required to achieve the best test effect during the rapid decompression test, is more than 1 : 50 [26]. The effective volume of the altitude chamber is 2.59 m 3 , and the volume of the vacuum chamber is 150 m 3 .…”

“…A study on free vibration of cylindrical shells with compressible fluid flow has been widely conducted [23][24][25][26][27]. Fluid vibration caused by the rapid decompression mainly occurs at the connecting pipe (throat) of two chambers.…”

Idealisations of Dynamic Modelling for Railway Ballast in Flood Conditions

“…Kaewunruen [3] has pointed out that it is necessary to determine their railway track exposure and the modal parameters of railway turnouts (switches and crossings) under flood conditions. For a better understanding of mechanical behaviours involving the railway ballast, it requires reasonable test methods and appropriate numerical models [68][69][70][71]. Therefore, the study of ballast in flood conditions by identifying the changing law and establishing an ideal dynamic model is particularly important.…”

The Research on the Damping of Prestressed Membrane Structure Subjected to the Impact Load

“…The question of how to analyze the response 2 of 14 of membrane structures under wind loads or other dynamic loads is very important, and the damping ratio is the key parameter for conducting this analysis. Liu Ping [20][21][22], etc., proposed a new analytical method to obtain some rules on the damping force of air applied to a membrane structure on the basis of no vortex assumption.…”