To simulate and calculate "the aero-optical transfer effects", an infrared imaging model was presented for applying the coordinate conversion method to trace any light in the space to figure out "the Optical Transfer Function (OTF)" and "the images". Based on the principles of geometry optical imaging and coordinate conversion, this method utilizes the density data based on the Computational Fluid Dynamics (CFD) grids of the hypersonic flow field to establish the model and emulate the blur effects of the field. And the results were contrasted and analyzed. The experiment results indicate that the model can reflect most of the known aero-optical blur phenomena in definite bound of precision. At last, we probe and discuss the precision and the significance of engineering application of the model.