The mathematical models and a numerical code for numerical simulation of a thermal anti-icing system are presented in this article. Mass conservation is applied to the runback water flow. An energy balance is imposed on the airfoil skin including the water flow. The heat transfer coefficient distributions are obtained using the boundary layer integral method. The external flowfield and the local water collection efficiency data are predicted using an Eulerian method, based on a computation fluid dynamic code and its user-defined functions. Given the input of the electrical power density distribution, the numerical code is able to calculate airfoil equilibrium surface temperature, mass flux of runback water, runback ice mass flux, and range if happens. A user interface is developed to integrate the computation fluid dynamic code to achieve a method for the analysis of a thermal anti-icing system. All the numerical results are compared with both experimental data and other numerical results presented in the literature.

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In this work, a simulated aircraft fuel tank inerting system has been successfully established based on a model tank.Experiments were conducted to investigate the influences of different operating parameters on the inerting effectiveness of the system, including flow rate of the inert gas (nitrogen-enriched air), inert gas concentration, fuel load of the tank and different inerting approaches. The experimental results show that under the same operating conditions, the time span of a complete inerting process decreased as the flow rate of inert gas was increased; the time span using the inert gas with 5% oxygen concentration was much longer than that using pure nitrogen; when the fuel tank was inerted using the ullage washing approach, the time span increased as the fuel load was decreased; the ullage washing approach showed the best inerting performance when the time span of a complete inerting process was the evaluation criterion, but when the decrease of dissolved oxygen concentration in the fuel was also considered to characterize the inerting effectiveness, the approach of ullage washing and fuel scrubbing at the same time was the most effective.

A novel 3-D unsteady model of in-flight electrothermal deicing process is presented in this paper to simulate the conjugate mass and heat transfer phenomena of water film runback, phase change, and solid heat conduction. Mathematical models of water film runback and phase change are established and solved by means of a loosely coupled method. At the current time step, solid heat conduction, water film runback, and phase change are iteratively solved until the heat boundary condition reaches convergence, then the temperature distribution and ice shape at the moment are obtained, and the calculation of the next time step begins subsequently. A deicing process is numerically simulated using the present model following an icing tunnel experiment, and the results match well with those in the literatures, which validate the present model. Then, an in-flight deicing process is numerically studied to analyze the effect of heating sequence.