Porous media gas bearings utilize gas as a lubricating medium to achieve non-contact support technology. Compared with traditional liquid-lubricated bearings or rolling bearings, they are more efficient and environmentally friendly. With the uniform gas film pressure of gas bearings, the rotating shaft can achieve mechanical motion with low friction, high rotational speed, and long service life. They have significant potential in improving energy efficiency and reducing carbon emissions, enabling oil-free lubrication. By eliminating the friction losses of traditional oil-lubricated bearings, porous media gas bearings can reduce the energy consumption of industrial rotating machinery by 15–25%, directly reducing fossil energy consumption, which is of great significance for promoting carbon neutrality goals. They have excellent prospects for future applications in the civil and military aviation fields. Based on the three-dimensional flow characteristics of the bearing’s fluid domain, this paper considers the influences of the transient flow field in the variable fluid domain of the gas film and the radial pressure gradient of the gas film, establishes a theoretical model and a three-dimensional simulation model for porous media gas bearings, and studies the static–dynamic pressure coupling mechanism of porous media gas bearings. Furthermore, through the trial production of bearings and performance tests, the static characteristics are verified, and the steady-state characteristics are studied through simulation, providing a basis for the application of gas bearings made from porous media materials in the civil and military aviation fields.

This study employs the one-dimensional flow simulation capabilities of GT-POWER software to develop a simulation model for an aviation two-stroke piston engine. The model is rigorously validated against experimental data, thereby ensuring a high degree of simulation accuracy. Subsequently, the resonant exhaust pipe of the engine is optimized using the Design of Experiments (DOE) method, with constraints imposed by the engine operating conditions and the spatial arrangement of the exhaust system. The optimization results indicate that the maximum power output of the engine is enhanced by 16.1% and fuel consumption is reduced by 14.2% under full-load operating conditions. These improvements highlight the significant potential of the optimized design for enhancing the performance of two-stroke piston engines in aviation applications.