Investigation of the heat transfer enhancement from jet film heating on aero-engine nose cone

A composite nose cone ice protection configuration with hot air film slot was investigated, where the air film was provided to heat the surface under the combined effect of both internal impingement heating and external film heating. The numerical simulation and experimental methods were adopted to study the internal and external heat transfer processes of the film heating anti-icing system and evaluate the heat transfer enhancement from jet film heating. Firstly, two-dimensional axisymmetric algorithm were adopted with the consideration of the heat conduction through the nose cone, and compared with those of the three-dimensional CFD computation in the Cartesian coordinate system and agreed well. Secondly, a hot-air blowing experimental apparatus was built up to verify the numerical simulation methods. Finally, the factors affecting the heat transfer characteristics were comprehensively investigated, including the Reynolds number, the relative impingement distance and the structural parameters of film slot. Results show that increasing Reynolds number is conductive to improving internal jet impingement heat transfer and external film heating efficiency. The optimal value of relative impingement distance increases with the increasing Reynolds number, and will be between 5 and 8 when Reynolds number is between 10,000 and 40,000.