A dual compact model for rotor thickness noise prediction

A new model, known as the dual compact thickness noise model, is developed for rotor thickness noise prediction. In this model, which is inspired by Isom’s thickness noise formulation, the airfoil is divided into two parts and a uniform pressure distribution is integrated on the front and rear part, respectively. This generates two loading lines, and the loading noise generated reproduces the thickness noise. This model is validated through computation for a wide variety of cases, in which different airfoils, blade planforms, and tip Mach numbers are considered. The dual compact approximation agrees well with normal thickness noise for each case. Less information is needed to compute the thickness noise, and computation time is significantly reduced by using the dual compact model (typically 25 times or more faster). Finally, the accuracy of the dual compact model can be further improved by simultaneously adjusting the magnitude and location of the two loading lines.