P3K-4 Utilizing a Ray Technique to Calculate Multiple Reflections and Transmitted Waves from Layered Plates and Examine the Detection of Critical Disbonds, and Lamb Modes Generated

This paper considers the problem of a single, or multilayer, isotropic plate and the problem of calculating the multiple reflections of acoustic waves within the plate, and the acoustic waves transmitted outside the plate (leaky waves). By using a ray method, and considering the paths traveled by the rays, it has been found that many of the multiple reflections will travel equivalent paths in space and time. Using superposition to combine the equivalent paths reduces the number of rays to track, and allows the process of calculations to be done in a time efficient manner. The use of the a ray model also gives initial results which are independent of properties of the incident acoustic waves. A separate set of calculations can be used expand the rays to a variety of more realistic acoustic waves, allowing a single result to be used for a variety of acoustic sources. The results from this model will be used to examine situations such as the detection of critical disbonds in plates, examination of the lamb modes which are generated, or examination of which situations produce the largest transmitted waves