A modified PEBI grid generation method with frontal approach is proposed,which is used to investigate reservoir modeling.Validity of the PEBI grid generation method is shown by comparing results of a self-developed reservoir simulator with that of a software CMG.A synthetic case with irregular boundary is investigated.It shows that PEBI grids reduce influence of grid orientation compared with conventional Cartesian grids.It is favorable to describe complex reservoir boundaries accurately and to implant internal constraints such as vertical well,fault in PEBI grid generation method.

A visco-elasticity polymer flooding mathematical model with three phases and five components is established with mass conservation principle.IMPES method is used to simulate the polymer flooding considering tackffying effect of elasticity,action of decreasing residual oil and visco-elasticity of heavy crude.It indicates that visco-elasticity polymer flooding decreases saturation of residual oil and increases viscosity of flooding system effectively,and then enhances oil recovery.As polymer concentration increases, oil recovery rises qucikly,and then tends stable.An optimal value is about 2 000mg·L^-1.As injection rate grows.oil recovery increases and then declines.There exists an optimum value.Oil recovery increases rapidly with the increasing of injection volume,and then tends stable.The best volume is 0.6PV.