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Direct Numerical Simulation of Automobile Cavity TonesThe Navier Stokes equation is solved computationally by the Dispersion-Relation-Preserving (DRP) scheme for the flow and acoustic fields associated with a laminar boundary layer flow over an automobile door cavity. In this work, the flow Reynolds number is restricted to R(sub delta*) < 3400; the range of Reynolds number for which laminar flow may be maintained. This investigation focuses on two aspects of the problem, namely, the effect of boundary layer thickness on the cavity tone frequency and intensity and the effect of the size of the computation domain on the accuracy of the numerical simulation. It is found that the tone frequency decreases with an increase in boundary layer thickness. When the boundary layer is thicker than a certain critical value, depending on the flow speed, no tone is emitted by the cavity. Computationally, solutions of aeroacoustics problems are known to be sensitive to the size of the computation domain. Numerical experiments indicate that the use of a small domain could result in normal mode type acoustic oscillations in the entire computation domain leading to an increase in tone frequency and intensity. When the computation domain is expanded so that the boundaries are at least one wavelength away from the noise source, the computed tone frequency and intensity are found to be computation domain size independent.
Document ID
20010061417
Document Type
Conference Paper
Authors
Kurbatskii, Konstantin
(Florida State Univ. Tallahassee, FL United States)
Tam, Christopher K. W.
(Florida State Univ. Tallahassee, FL United States)
Date Acquired
August 20, 2013
Publication Date
August 1, 2000
Publication Information
Publication: Third Computational Aeroacoustics (CAA) Workshop on Benchmark Problems
Subject Category
Acoustics
Funding Number(s)
CONTRACT_GRANT: NAG1-1986
CONTRACT_GRANT: NAG3-2102
CONTRACT_GRANT: NAG1-2145
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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IDRelationTitle20010061385Analytic PrimaryThird Computational Aeroacoustics (CAA) Workshop on Benchmark Problems
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