Abstract: With the improvement of the imaging resolution of thermal infrared（IR） imager, more and more new target infrared image synthesis has been observed. To explore the causes and specific image synthesis of IR wake of sea ships from aerial images, we propose a novel modeling and rendering algorithm for IR wake of sea ships based on fluid dynamics and infrared physics in this paper. Our algorithm first hires voxelization to convert the ship body into solid particles for solid-liquid coupling simulation. Then, a vertical temperature distribution model of seawater is put forward to determine the initial temperature value distribution of fluid particles. To simulate the motion and change of infrared synthesis of navigating sea ship scene, a new model combined with smoothed particle hydrodynamics（SPH） and seawater heat conduction mechanism is proposed. Finally, realistic infrared ship wake scenes are successfully rendered according the infrared image synthesis model. Our method can simulate not only the geometric change but also the IR physical feature change of the ship wake area. We thus prove the causes of IR ship wake image from the view of experimental simulation, which can be found potential applications in the domains such as target detection and rescue on sea surface, and the infrared stealth and countermeasure in the military affairs, etc.