Correlation of nonlinear orifice impedance

Abstract

Dimensional analysis of the orifice impedance problem produces several sets of nondimensional variables which may be used to correlate nonlinear orifice behavior. Published experimental data on thin orifices were examined and it was found that tests with oil, water, and air can be correlated. Graphs of orifice resistance are given in nondimensional forms that are useful over a wide range of conditions. The form for resistance is R/ρ (νω)1/2 as a function of an aspect ratio parameter l/d, an orifice velocity parameter V/(νω)1/2, and a diameter-viscous parameter d/(ν/ω)1/2. For thin orifices the resistance is independent of d/(ν/ω)1/2 when this parameter is greater than 10. Nonlinear effects begin when V/(ν/ω)1/2=3. This parameter compares the displacement amplitude to the viscous diffusion length. The reactance end correction δ was normalized by the Rayliegh value of 8d/3π and correlated using the variables l/d, V/ωd, and d/(ν/ω)1/2. Again thin orifices show no dependence on d/(ν/ω)1/2 for values greater than 20 and the nonlinear reactance region begins at V/ωd=0.1. Thus, different parameters govern the onset of nonlinear resistance and reactance. Subject Classification: [43]85.20, [43]85.50; [43]28.60.

Characterization of a gas‐liquid OBC: Bubble size and gas holdup

“…This new approach considered that the turbulent energy dissipation was localized near the edges of the plates in the same way as in acoustic flows. The acoustic model was based on the work of Panton and Goldman (1976), who showed that at low acoustic intensities the frictional pressure drop at an orifice was related to the kinematic viscosity of the fluid. Baird and Stonestreet (1995) replaced this kinematic viscosity with a much greater eddy kinematic viscosity, based on the assumption that the eddy size in an OBC is much smaller than the tube diameter at high oscillations.…”

Acoustic properties of perforates under high level multi-tone excitation

“…here is a large number of papers on the effect of high level acoustic excitation on the acoustic properties of perforates and orifice plates [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] . Orifice plates and perforates appear in many technical applications where they are exposed to a combination of high acoustic excitation levels and either grazing or bias flow or a combination.…”

Effect of hydrodynamics on mass transfer in a gas–liquid oscillatory baffled column

“…Extensive research on gas-liquid contacting has been undertaken in conventional bubble columns and stirred tank vessels [1][2][3][4][5][6][7][8][9][10][11][12][13], and the latter has been the standard device in fermentation industries worldwide. The oscillatory baffled column (OBC) has recently emerged as a viable alternative to those vessels, since it can provide enhanced mass transfer performance [14,15].…”