This paper studies the gas ejector, a two-dimensional trajectory mathematical model of gas ejector. It designs and develops visual programming software to complete the zero-dimensional interior ballistic mathematical model on the.Net platform and the numerical simulation of trajectory mathematical model of two-dimensional calculation integration. The model focuses on the simulation of trajectory in two-dimensional mathematics. The core is that Fluent is secondary developed by C# language. Engineers design the parameters in the custom GUI interface. The integrated software can be studied under different proportion, pressure, velocity, temperature and flow data. It saves a lot of time to master the engineering background and set the interface of Fluent software parameters, greatly improving the efficiency of researchers, which is suitable for repetitive experimental research. It provides theoretical and technical support for the prediction and measurement of the gas flow parameters.