Studies Of Electro-thermal Anti-icing System For Aircraft Windshield

When the plane fly through the cloud, cloud of super-cooled water droplets hit the plane upwindand freeze, leading to serious aircraft icing. The purpose of this paper is to analyze the problems of theexisting anti-icing system and to give suggestions for improvement contra-posing the crack problemsin the actual use of electric heating windshield of a certain type of aircraft.. Numerical calculationmethod is used to evaluate the anti-icing heating load of the windshield. And the test is carried out onthe windshield to correct the numerical results.This research includes the following aspects:1.A three-dimensional model of the windshield isestablished, grid of which is divided using the software ICEMCFD. The external flow field of thewindshield is calculated by importing the grid into the software of FLUENT.2. The wind tunnel testsand cold winds blowing tests are carried out on heated windshield to get the test value of heat transfercoefficient on the outside surface of windshield, using which numerical calculation values is correctedand the heat transfer coefficient is got.3. The motion equations of Euler-type air/super-cooled waterdroplets are used to solve the water-drop hitting character on the surface of three-dimensionalwindshield, in order to get water collection coefficient in a variety of flight altitude, speed, icingweather conditions.4. From the N-S equation of incompressible laminar flow, dimensional analysis isused to simplify the problem. Then the water film flow control equations for complexthree-dimensional anti-icing surface are deduced.5. In conditions of the continuous maximum andintermittent maximum icing weather, the anti-icing heating load for the cases of achieving threedifferent anti-ice effects is evaluated. And considering the engineering implementation factors, thevalue is reverse checking calculated, then the required heat flux for anti-icing is determined.6. Themain problems of the existing anti-ice electric heating system in windshield were analyzed andreasonable suggestions and measures for improvement are given.