No abstract

In this paper, attempt has been made to minimize sound reflection from the wall by using Taguchi's method and to find optimal structure for the suggested test-section inside the cavitation tunnel. The suggested structure which was added to the test-section is funnel-shaped with a performance like a check valve. In order to obtain approximate values of five independent parameters, three levels were taken into account for each parameter. By combining parameters of different levels, 27 tests were designed using Taguchi's method and Minitab Software. Different acoustic analyses were conducted in COMSOL Multiphysics software, and defined parameter of general reflection coefficient was obtained for 21 observer points. Applying the general reflection coefficients to Minitab Software and drawing the SNR graph, approximate values of the parameters were obtained. However, these values did not produce enough accuracy to design the optimal structure. For this reason, five levels around optimal values, obtained from the previous analysis, were considered for each parameter. Same steps were repeated again for the parameters at five levels and optimal values were obtained. Optimal structure was modelled and analyzed. Consequently, appropriate defined parameters of general and local reflection coefficients were extracted which represented an optimal structure for the intended test section.