Torsional elastic waves in tubes. Improved dispersion curves

In the last decades, there is an increasing interest in locating defects in pipeline from the chemical and nuclear industries using ultrasonic torsional waves. In this paper, the authors are presenting a theoretical study and numerical calculation using Matlab for the dispersion equation of torsional waves in pipes. Even though implementation of the dispersion equation in a computer program was not a simple problem, the authors have succeeded in obtaining very good results compared to those from existing references. Major improvements compared to a recent communication of the same authors, led to accurate dispersion curves for order zero torsional modes.