【摘 要】
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The predictions of noise directivity of an impinging jet on the flat plate are carried out using the large eddy simulation(LES)and the Ffowcs-Williams and Hawkings(FW-H)acoustic analogy.Firstly,flow f
【机 构】
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School of Energy and Power Engineering,Huazhong University of Science & Technology,Wuhan,People's R
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The predictions of noise directivity of an impinging jet on the flat plate are carried out using the large eddy simulation(LES)and the Ffowcs-Williams and Hawkings(FW-H)acoustic analogy.Firstly,flow field of the proposed model is simulated and analyzed with different impinging distances under a certain impinging velocity.Secondly,sound pressure level(SPL)of different noise monitoring points are calculated under a range of impinging distances and various impinging velocities.Finally,combined with numerical result of the flow field,noise directivity of the impinging jet is analyzed.It is indicated that main noise sources consist of the dipole source generated by pressure fluctuation on the plate surface and the quadrupole source generated by the turbulent jet.In addition,the impinging velocity and the impinging distance have a significant effect on the regularity of noise directivity.
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