MAIN STREAM ISOLATION VALVE NOISE REDUCTION METHOD

摘要

PURPOSE: A main stream isolation valve noise reduction method is provided to derive a calculation method of noise radiation effect after a corner cutting, and to determine the effective triangular corner cutting. CONSTITUTION: The main stream isolation valve noise reduction method includes the first step for simulating of setting the eddy as an eddy point, the second step for calculating the flow velocity of the flow field, the third step for tracking the moving trajectory from Lagrangian point of view, and the fourth step for calculating the magnitude of noise source by using the flow information. The forward step problem in the first step has an assumption of a non-compressed and non-viscous flow. In the second step, the physical spatial coordinate having a plurality of steps is transformed into the infinite flat coordinate by the Schwartz-Christoff transform. By using the matched asymptotic expansion the wave equation is obtained.