Reflection characteristics of a sound absorbing wedge are related to acoustical properties of material as well as wedge dimensions. However, there are no reliable values of the acoustical properties of materials, so wedge design problems have been experimentally solved in each case. In this paper, the values of acoustical constants of glass wool such as flow resistance, effective density and effective volume elasticity are investigated and it is confirmed that the most important factor is the flow resistance. Next, the wedge design including selections of material and wedge dimensions are studied by the computer simulation whose results agree well with experimental results, and the useful results about the influence of base length, air space and wedge angle on the absorbing characteristics of wedge are obtained. Among these results, the most interesting one is that the wedge having satisfactory characteristics can be made by choosing the optimum base length corresponding to the value of flow resistance.
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