Abstract:
Taking bump-type gas foil bearing as the research object, the mechanical properties of bump foil are studied using the elastic mechanics theory, a force and deformation model is established, and a fluid-solid coupling algorithm is established on the basis of Reynolds equation of coercible gas. An example is given to compare the gas film pressure distribution and the film thickness distribution of elastic foil gas bearings with those of rigid gas bearings. It was found that the distribution shapes of the pressure and gas film were similar, but the maximum gas film pressure of the elastic foil gas bearings was smaller, while the minimum gas film thickness at the axial bisector was larger. With the same eccentricity, the friction torque of the elastic foil gas bearings was smaller than that of the rigid gas bearings, and the side leakage flow of gas was larger than that of the rigid gas bearings. The friction torque of the elastic foil gas bearings during working was smaller with less heat generation and faster heat dissipation. Increasing the thickness of bump foil (
tB) or decreasing the wave distance of bump foil (
s) can reduce both the minimum gas film thickness and the attitude angle of bearings. Decreasing
tB or increasing
s can reduce the friction torque resulting in less friction power loss and friction heat generation, as well as increase in the side leakage flow of gas resulting in faster heat dissipation.