Thermal analysis of hydraulic system of landing gear

Abstract

Landing gear of any aircraft is an important system which aids in takeoff, landing and supports the aircraft on runway. Landing gear system employs a hydraulic actuation system for its operation. Hydraulic system provides pressurized hydraulic fluid for actuation of main and nose landing gear in deployment/retraction mode and brake pressure for braking. Advantage of Hydraulics is small sized actuators due to its high power density, easy control and transmission of power. Hence hydraulics always had been a preferred choice for compact high power systems. During the energy conversion, fluid transmission losses and inherent friction, heat energy is generated in the system which rises the fluid temperature. This heat has to be dissipated by proper means to maintain the system temperature within safe limits. This paper attempts to study the thermal aspects of hydraulic system, heat generation and dissipation to estimate temperature rise profile and steady state temperature.