Numerical Simulation Of Aircraft Ship Coupling Flow Field During Taking Off And Landing Of Shipborne Helicopter

Helicopter has the advantages of vertical take-off and landing,low requirements for take-off and landing site and rapid task response.It is widely used in various offshore platforms.Compared with land take-off and landing operations,the flow field in the ship take-off and landing area is extremely complex and there are many restrictive factors,which makes the take-off and landing process of Shipborne helicopters very risky.In this paper,through CFD(Computational Fluid Dynamics)technology and large eddy simulation based on lattice Boltzmann method,the take-off and landing process of Shipborne helicopter is numerically simulated,and the characteristics of aircraft ship coupling flow field in the take-off and landing process are studied and analyzed.Firstly,the feasibility of large eddy simulation based on lattice Boltzmann method for complex flow field is verified by the comparison of different numerical calculation methods and the comparison with the classical turbulence model.Then,the calculation models of ships and shipborne helicopters are established from the public data.Based on meshless method and wale turbulence model,the characteristics of aircraft ship coupling flow field without considering / considering helicopter are compared and analyzed.The results show that the numerical simulation results of aircraft ship coupling flow field considering the influence of helicopter are closer to the actual situation.Finally,aiming at the normal vertical take-off route of helicopter,as well as three landing routes: stepped vertical landing,normal vertical landing and fixed glide line landing,the influence of different wind angles on the take-off and landing process of Shipborne helicopter is simulated and analyzed.At the same time,based on the normal vertical landing route,the effects of different entry angles on the helicopter landing process are studied and analyzed.Based on the research and analysis of the force variation curve of the shipborne helicopter fuselage under different working conditions and the characteristics of the aircraft ship coupling flow field,the flight altitude range affecting the take-off and landing safety of the shipborne helicopter is obtained,which provides some guidance and suggestions for the helicopter pilot.