Abstract: Numerical methods for energy flux of temperature diffusion equation on unstructured grids are discussed.A finite point method(FPM) is used to get numerical formulae of energy flux based on two-point formula or three-point formula of FPM.These formulae are applicable to unstructured grids,such as arbitrary polygon and unmatched grids etc..A numerical formula is given to compute tem-peratures at grid nodes.Numerical experiments show that the discrete solutions based on two-point formula and three-point formula have second-order convergence rate even if grids distort heavily.Accuracy of the discrete solutions based on three-point formula is better than that of two-point formula.

Key words: diffusion equation, unstructured grid, finite point method formula, energy flux computation