Study And Experiment On The Characteristics Of Water Droplet In Aircraft Icing Calculation

With the development of the aciation industry,more and more attention has been paid on the problem of aircraft icing. At present, the methods of aircraft icing research have flight test, ice wind tunnel experiment and numerical simulation method. And the numerical simulation method because of its low cost, speed and other characteristics become the main method of researching icing problem. According to the numerical simulation of aircraft icing process,Euler characteristic calculation and icing water droplets based on dynamic mesh unsteady calculation method are studied in this paper, experimental study on the phenomenon of splashing, breaking and rebound in the process of water drop impact is carried out.The main content of this paper is divided into five chapters. The first chapter gave a brief description of the hazards of aircraft icing, introduces the current domestic and international research direction and the main methods and results of aircraft icing. The second chapter described the basic process of numerical simulation of aircraft icing, grid generation, flow field calculation, ice generation calculation method are briefly introduced in this chapter, the methods of grid generation, flow field calculation, water droplet trajectory calculation and iced shape calculation are introduced. Focused on the calculation method of characteristics of water droplets based on Lagrange method and Euler method, and introduced the concrete solving process, based on the Messinger model, a two dimensional ice growth model is established and a method for solving the icing profile is presented. The typical icing meteorological conditions of icing calculation example and by comparing the calculation results with experimental results and other software calculation results, verify the droplet trajectory and ice shapes calculation method is correct. The third chapter introduced three kinds of dynamic grid numerical model: Smoothing model, Layering model and Remeshing model, analyzed three kinds of scope of application of the dynamic mesh model and applied to aircraft icing numerical feasibility for unsteady aircraft icing problem. In view of plane unsteady icing problem is presented using Remeshing and Smoothing model combined with the scheme for the simulation of aircraft icing realizing the dynamic update of aircraft icing boundary calculation in freezing process, under the condition of unsteady ice shape and steady icing calculation method were compared with the results of the calculation and analysis of the differences and reasons, the calculation results show that the unsteady icing calculation can improve the precision of the numerical simulation of aircraft icing.In the fourth chapter, the droplet impingement property were stuied through a combination of experimental and numerical methods of different incident velocity and different incident angles and different surface roughness of water droplets impingement characteristics, by using numerical simulation method calculated the water drops from splashing on droplet impingement property and effect of the iced shape The fifth chapter carries on the comprehensive summary to the full text work, and carries on the forecast to the future work.