The invention discloses a dissipative particle dynamics method for building a tension-shear coupling flow field. The method comprises the following steps that S1, a UHMWPE/PA initial structure model is built; S2, the UHMWPE/PA initial structure model is optimized; S3, boundary conditions for achieving the tension-shear coupling flow field are provided; S4, the boundary conditions in S3 are substituted into a topographic structure in S2; S5, if the pressure fluctuation range of the optimized topographic structure after the dynamic equilibrium is less than 10%, the process ends, otherwise, S4 isexecuted. By providing the boundary conditions and the dissipative particle dynamics method for building the tension-shear coupling flow field, the phenomenon that due to the fact that in traditionalsimulating computation, single boundary conditions are adopted, simulation results are inaccurate is avoided. Accordingly, the dynamic process of structural transformation and phase separation in thevolume-stretched rheological control polymer processing can be truly reproduced, the defects of experiment research are effectively overcome, and the method is particularly applicable to ultra-high molecular weight polyethylene with ultra-high molecular weights and ultra-long molecular chains and blending and compounding systems thereof.
