Mohammad Abbaszadeh - PhD Candidate, Mechanical Engineering Department, Shiraz University, Shiraz, Iran
Salman Nourazar - Associate Professor, Mechanical Engineering Department, Amirkabir University of Technology, Tehran, Iran

In this paper, we apply the modified homotopy perturbation method (HPM), incorporating He’s polynomial into the HPM, combined with the Fourier transform, to solve the nonlinear Fisher equations. The solutions introduced in this study can be used to obtain the closed form solutions when required. The analysis is illustrated by investigating three partial differential equations with variable coefficients. Results show the effectiveness and the accuracy of the proposed model. Moreover, the combined method needs less work in comparison with the other homotopy perturbation methods and decreases volume of calculations considerably

Fisher equation, Fourier transform, Homotopy perturbation method, Non-homogeneous partial differential equation