Accounting for the liquid compressibility, the radial movement of single cavita tion bubble in oscillating pressure field has been investigated numerically. It shows that the bubble motion presents intense nonlinear feature and there will be bifurcation and chaos under some condition.
Based on DeltaE model,the distributions of oscillating pressure,volume flow rate,temperature,acoustic power and phase inside the loop section and resonator of the traveling wave thermoacoustic engine are analyzed. The trend of traveling wave and standing wave in the system is present and some valuable conclusions are drawn.
Then, the tube vibrations induced by the varying fluid forces were predicted by solving the solid mechanics equations. The full functional analysis method was then applied to predict the fluidelasticity stability condition. Analysis of the propagation characteristics of the oscillating pressure was used to study the flowinduced vibrations including acoustic resonance.
No statistically significant changes was observed in the amplitude pressure, though the median amplitude pressure decreased from (48±7) cmH 2O to (41±7) cmH 2O ( F =1.98, P >0.05).
It can be seen from the test traces that the frequency shifts of acoustic pressure os cillations during the growth period and decay period are slight (less than 5%and 10%, respectively), and the difference between those frequencies is slight.
For two typical sections of ship hull, of which one is the midship section of a fishing vessel, the other is at the bow of a container ship, the oscillatory pressure and impact pressure are calculated, and the diagrams of pressure distribution along the section's contour are obtained for the different drafts or frequencies.
The solution to the problem of Viscous flow under the influence of an oscillating pressure gradient [8] is generalized to the case of a two-layer distribution of the viscosity.
This work extends PSP's useful range to dynamic systems where oscillating pressure changes are on the order of 230?Pa and occur at frequencies in the range of 95-125?Hz.
A linearized theory is developed for the derivation of an asymptotic solution of the initial value problem of axisymmetric surface waves in an infinitely deep fluid produced by an arbitrary oscillating pressure distribution.
The special shape of the upper boundary of the computational domain, together with the oscillating pressure gradient causes the boundary layer flow to alternately separate and re-attach.
A modified test burner device, based on the conventional T-burner and T-motor, called pressure-controllable burner has been constructed for measuring the response function of solid propellant combustion. On this device is mounted a controller system which can modulate the mean pressure in the burner's chamber according to the test need, and maintain the same pressure level after burnout as before. It can be seen from the test traces that the frequency shifts of acoustic pressure os cillations during the gro...
The research method and experimental results of unsteady aerodynamic charactristic of a group of turbine blades tested in a subsonic oscillating cascade wind tunnel are described in this paper. Type of blade vibration: pure torque; frequency: 1 Hz; amplitude: 2°. The influence of various incidence angles and different interblade phase-angles on unsteady aerodynamic charactristic of an oscillating cascade is illustrated. The distribution of oscillating pressures on blade surface and the velocity field inside...
The computation of oscillatory pressure and impact pressure for two-dimensional bodies with arbitrary shapes is described.Considering the effect of piling-up of water and the variation of immersed shape,the valuation of impact pressure on the two-dimensional body during vertical water-entry at a constant velocity is simplified as a series of problems of flow around body.To solve these problems, the multi coefficient conformal transformation technique is used.For two typical sections of ship hull, of which o...