Research On Helicopter Wheel Impact Load And Deck Structure Respones

With mankind gradually moving from shallow sea to deep sea,helicopters are used more and more frequently in the marine field,which can efficiently complete the tasks of personnel transportation and marine supply.Helicopter will produce a complex impact load when landing on ships and marine structures.In order to ensure the structural strength of helicopter deck under landing conditions,it is necessary to research the wheel impact load on deck and the structural response of deck under the impact load when helicopter landing.In this paper,the impact loads and corresponding structural responses of a helicopter deck frame under the impact loads are researched by numerical simulation method.The methods to solve the dynamic equation of collision impact condition and the current international mainstream classification regulations on helicopter deck load under landing impact load are introduced.Combined with the physical model of helicopter landing,the process,object and the numerical simulation are determined.Nonlinear spring is used to simulate helicopter landing gear cushioning system.Considering the basic configuration of tyre,a reasonable simplified tyre model is established.The static grounding test of tyre is simulated,and the rationality of the simulation and analysis methods is verified by comparison.The numerical simulation process is divided into tire inflation process and the impact process,which simulate the process of landing on deck.Three different levels simplified models are compared to verify the necessity of simulating tyre and helicopter landing gear in this paper.The parametric analysis is carried out for tyre pressure,friction,landing speed and landing position.And the effects of different parameters on the impact load and deck structure response during the landing process are researched.According to the research results,the landing speed and location have great influence on the impact load and the deck response.In order to facilitate the practicability of the project,the static equivalences for the dynamic calculations are carried out.In this paper,three equivalent methods and the corresponding dynamic amplification coefficients are adopted.The effects of landing speed and landing position on the dynamic amplification coefficients are analyzed.The research results in this paper can provide references for the formulation of helicopter deck specifications,design verification and optimization of helicopter deck.