A Graphical Edge Method to Solve Dispersion Equation of Lamb Waves

Lamb wave dispersion curves are the fundamental of Lamb waves-based research and engineering application. Numerical solution is the only way to solve Rayleigh-Lamb equation and then the dispersion curves are obtained. Traditional-bisection method requires complex root intervals analyzing. A graphical-edge method is presented to simplify the process of solving dispersion equation of Lamb wave. First, solution intervals of the Lamb wave dispersion equation are divided and the standard dispersion equation is modified. Next, the graphical method is used to visualize abstract formulas. Combined with graphic boundary extraction method, the phase velocity dispersion curves are plotted. Graphic edge method can represent complex and abstract formulas graphically, simplifies the solution process and improves the solution efficiency.