航空发动机风扇地面慢车关键结冰温度分析

摘要

根据《航空发动机适航规定》中第33.68条"进气系统结冰"的要求,发动机需在地面慢车状态下进行结冰试验验证,并应在-9~-1 ℃的环境温度范围内选择结冰最严重的温度点作为试验温度.风扇是发动机首当其冲的结冰部件.为确定某型发动机风扇在该温度范围内的关键温度点,基于Messinger结冰热力学模型,利用FENSAP-ICE软件对风扇进行了结冰计算.通过结冰质量的比较分析,获得了风扇的关键结冰温度点.计算结果显示,风扇结冰质量随环境温度呈两个阶段的变化趋势:在-9~-6 ℃范围内,结冰质量不随温度变化,单个叶片保持在0.29 kg;在-6~-1 ℃范围内,结冰质量随温度升高呈二次曲线的下降趋势.因此从结冰质量的角度来看,风扇在地面慢车状态下的关键结冰温度为-9~-6 ℃.%According to CCAR 33.68 "Induction system icing" requirements on "Aircraft Engines Airworthiness Standards", engine ground idle icing test must be executed, and the critical ambient temperature should be selected in the range of-9~-1 ℃.The fan is the first icing part of engine, in order to define the critical icing temperature, FENSAP-ICE based on Messinger icing thermodynamics model was used on the icing simulation, as a result, the critical icing temperature was found in comparison with the icing mass of cases.The result of simulation shows that, the fan icing mass varies with temperature in two different tendencies: in range-9~-6 ℃, the icing mass of single fan keeps in a constant value of 0.29 kg;in range-6~-1 ℃, the icing mass decreases following increasing of icing temperature, with a quadratic polynomial tendency.Therefore, in aspect of the fan icing mass, the critical ambient temperature for engine ground idle icing test should be-9~-6 ℃.