Currently, with the updating and iteration of nuclear energy technology, the power supply technology of fourth generation nuclear reactors and space nuclear reactors is flourishing. Core cooling is one of the core components of the entire nuclear reactor technology, and electromagnetic pumps are widely used in liquid metal cooling methods. This article will establish a three-dimensional electromagnetism-flow coupling numerical simulation method based on a simplified engineering model of a planar linear induction pump, using professional electromagnetic simulation software Ansys Maxwell and professional CFD simulation software Simcenter STAR-CCM+. By calculating the multi flow conditions of different liquid metal working fluid temperatures, the head, electromagnetic, and flow characteristics of FLIP were obtained, and the influence of liquid metal working fluid flow rate and temperature on the above characteristics was explored. Finally, the influence of the non-uniform distribution of Lorentz force acting on liquid metal in time and space on the head characteristics of the pump was analyzed, and a reasonable simplification method based on FLIP three-dimensional electromagnetic flow coupling numerical simulation method was proposed for application in engineering practice.