Abstract
<jats:p>In connection with the appearance of new projects of unmanned aerial vehicles (UAVs) with a pulse jet engine, modeling their parameters and characteristics becomes relevant. However, despite a large number of research works and developed theoretical models of the working process, no calculation programs suitable for wide practical use and modeling of a pulse jet engine have been created for many years. Therefore, the subject of this work was valved and valveless pulse jet engines, and the goal of the work is to create a mathematical model and a real online program for modeling the working cycle of a pulse jet engine, available to a wide range of users. Therefore, it was necessary to solve the following problems: develop a mathematical model of processes in the combustion chamber, intake system, and resonance tube of a pulse jet engine, develop and debug an engine modeling program, place it on a special website, and model known engines to verify the model. Research methods. The model is based on the thermodynamic model of the process of volumetric combustion and gas exchange in the combustion chamber, on the method of "piston" analogy for non-stationary gas and air flow in the resonance pipe of the pulse jet engine and in the valveless engine’s intake pipe. The model includes a mathematical description of the dynamics of the valve petal movement and the non-stationary process of heat exchange with the walls. Results. The first developed special online program Pulsejet-Sim, built on a special data structure with division into server and client parts, provides the implementation of the model. The program is implemented as a web-oriented software service that does not require downloading to the user’s computer compared to traditional desktop packages and programs. This allows instant calculations using server resources and secure data storage in the cloud. Conclusions. With the help of the developed program, preliminary mathematical modeling of known pulse jet engines has been performed, which has shown satisfactory qualitative and quantitative agreement between the modeling results (error less than 10%) and the available experimental data on the main parameters. Previously unknown characteristics of pulse jet engines, including the indicator diagram, were obtained.</jats:p>