With analyses of field production data and numerical simulations,solvent-enhanced steam flooding (SESF) production process is divided into three stages. By integrating mass conservation equation, energy conservation equation, motion equation and diffusion equation, a mathematical model was obtained to describe steam front development.The expression is a typical Volterra integral function of the second kind and could be transformed by Laplace transformation.It is solved by discretizing time and space into small intervals. With comparison of calculated results and those of STARS, relative error of less than 4% for whole process is found. The model provides an accurate and quick method for analyzing effects of solvent properties and injection strategies on SESF production process.

It focuses on an approach to generating 2D unstructured grids for the solution of Euler equations.Unlike the generation of unstructured grids before with background grids,the background information needed in Avancing Front Method is obtained directly with the distance to the airfoil surface.In solving the Euler equations,the cell centered finite volume method is used for space discretization,and four step Runge Kutta method is adopted for time marching.Two kinds of boundary condition are presented and three kinds of boundary conditions are applied and analyzed.The calculated results are given and discussed.