A Consistency Test of Thickness and Loading Noise Codes Using Ffowcs Williams and Hawkings Equation

[摘要] The thickness noise predicted by the Ffowcs Williams and Hawkings(FW&H) equation depends on the normal velocityvnwhich is very sensitiveto the meshing size. Isom showed that in far field a monopolar source isequivalent to a dipolar source induced by a uniform distribution of theload on the entire moving surface. The main objective of this paper isto determine a specific expression of Isom's thickness noise in time andfrequency domains for subsonic fans. The scope of the proposed expressionof Isom's thickness noise is to define a benchmark test of consistency forthickness and loading noise codes in both time and frequency domains forsubsonic fans when using the free field solution of FW&H's equation.

[学科分类] 声学和超声波