Abstract—Hydro-pneumatic spring have been widely used in the field of vehicle suspension because of the typical nonlinear characteristics, but the high working temperature will influence the viscosity of oil and the endurance life of rubber seal, therefore, it is particularly necessary to study the thermal dynamics of the hydro-pneumatic spring. In the article, the differential equations of oil and gas medium temperature variation with internal energy are derived, in addition, the random excitation input of hydro-pneumatic spring is determined by dynamic modeling. After that, the thermal equilibrium temperature of hydro-pneumatic spring under different pavement excitation are simulated and analyzed, it can be used to guide the design of suspension.
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