防冰表面的对流换热计算分析

利用动量和热边界层积分分析的方法对采用电热防冰的二维机翼对流换热系数进行了数值计算,比较了等温突捩以及变温光滑两种不同的边界层模型.层流向湍流转捩的起始点位置和过渡区域的长度由经验公式判断,并通过内外热流耦合迭代求解得到了防冰表面的平衡温度,与文献试验值进行了比较.所得结果表明:加入过渡区模型可较好地预测对流换热系数及防冰表面温度.同时,结果还表明环境压力变化对换热系数的的影响较大.

Convective heat transfer analysis of anti-icing surface

An integral analysis of momentum and thermal boundary-layers was used to determine the convective heat transfer coefficient on two-dimensional airfoils with thermal anti-ice system. The objective are to implement two different boundary-layer models: one assumed isothermal surface with prensence of a abrupt laminar-turbulent transition, while the other considered the boundary-layers over a non-isothermal surface with a smooth laminar-turbulent transition region. The onset and length of laminar-turbulent transition was estimated by classic empirical correlations. The surface equilibrium temperature distribution was predicted by an integrated airoil leading-edge interior-exterior thermodynamic analysis, compared to the literature and experimental data. The results indicate a validity of using boundary-layer anaylysis with smooth laminar-turbulent transition in predicting anti-icing convective heat transfer and surface temperature, but the simulation shows that surrounding static pressure has a large effect on the results accuracy.