Comparison of Dynamic Shear Modulus Measurements on Two Damping Materials

摘要

In order to ascertain the current state-of-the-art for direct measurements of the dynamic shear modulus of damping materials to be used in controlling ship acoustic noise, four participants made measurements on two materials and their results were compared. This comparison showed large differences which were attributed mostly to measuring techniques or apparatus. Because it could not be definitely ascertained which results were in error and by what amount, a particular method is not recommended. Investigation of the use of indirect methods and new or modified direct methods is under way at MEL to achieve a reasonable solution to the measurement problem and permit optimum design of constrained damping configurations and material procurement. (Author)