Impact And Floating On Sea After Landing By Parachute

The sea landing has several advantages. The sea have a broader area，the landingimpact of the sea is far less than that of the land and confidentiality is better. But thesea state is variable, and the complexity and variability of effect of the capsule orhelicopter makes the landing and floating on sea of capsule or helicopter has becomemore difficult to predict and control. So it’s necessary to research the response ofcapsule and helicopter under sea state, and the paper mainly not only carry out thesimulation analysis of impact onto sea of capsule under sea state after falling byparachute, but also analysis of impact and floating of helicopter under sea state.Parachute is one of most important tool to decelerate the velocity of capsule, solanding process of capsule by parachute is studied before capsule’s impact on sea, forthat a numerical flow field is built by ALE(Arbitrary Lagrange-Euler) method, and aplane circular parachute that has been simplified is simulated in infinite mass andlimited mass of a capsule to provide a research method of system of parachute.And a numerical-wave-tank is built. The study of capsule’s impact onto the seawaves may provide the reference for capsule’s design and manufacture for landing ontothe sea by accidence or by plan. The results show that horizontal velocity has asignificant effect to the maximum impact acceleration of the capsule under waveconditions, which is not under static water.At the end, simulation of floating on calm water of helicopter is carried on, andwaterline of helicopter been given mass is got. At the base of simulation of floating oncalm water, simulations of landing impact on calm water and floating on wave areconducted. Through the analysis of results of simulation, maximum acceleration ofimpact on calm water and maximum attitude angle of floating on wave of grade threeare gained.