Research On Aircraft Wake Vortex Encounters Response And Risk Assessment Method

With the rapid development of the civil aviation industry,the wake has become the main factor restricting the optimization of the safety separation of the aircraft.In order to evaluate the wake encounters of aircraft and carefully reduce the wake separation under the condition of ensuring safety,it is necessary to conduct an in-depth study on the response mechanism of aircraft wake encounters,positive explorations were carried out in this paper.Firstly,the wake vortex flow model was established by the Hallock-Burnham wake vortex induced velocity model,and a six degree of freedom flight dynamics model was established based on the flight dynamics principle.On this basis,a rapid calculation model for calculating the maximum rolling slope angle of the aircraft in the wake encounter was established.The simulation of the wake encounter between the heavy aircraft A350 and the medium aircraft B737 in the non-vortex core region was carried out.The advantage of rapid calculation model is that takes short time,which was proved by case analysis.The specific effects of key parameters such as separation on the risk degree for aircraft wake encounters were analyzed.Secondly,a nonlinear aerodynamic model was established for the wake encounter at the vortex core,and the response mechanism of the aircraft after encountering the wake at the vortex core was studied by MATLAB/SIMULINK.The motion scene of the aircraft under the six degree of freedom dynamic model was simulated.The rapid calculation model and the nonlinear aerodynamic model were compared and analyzed.The rapid calculation model is suitable for the study of the wake encounter in the non-vortex core region.The nonlinear aerodynamic model is suitable for the study of the wake encounter at the vortex core.Finally,according to the current wake safety separation standard,the risk assessment of the aircraft wake encounter was carried out,and the distribution proportion of different hazard level areas in the dangerous area of the wake vortex flow were calculated.An warning system was established according to the tangential velocity of the corresponding wake vortex flow when the aircraft reaches the maximum lift coefficient.A control loop was designed for the established wake encounter response calculation model.The effectiveness of the control loop was verified by simulation.