摘要:
结冰风洞试验是进行飞机结冰和防除冰研究的主要手段,结冰试验相似准则是进行结冰风洞试验的理论基础。针对目前的结冰试验相似准则在明冰模拟方面的不足,本文采用液/固相变的基本理论,对飞机结冰过程的液/固相变传热特性进行了分析和研究。在此基础上,提出了一个新的结冰试验相似参数CT,该参数与基于Messinger结冰热力学模型所得到的相似参数的主要区别是考虑到了结冰的干模式和湿模式,体现了相变的时间效应。通过将新的相似参数引入现有结冰试验相似准则中,可有效避免试验压力与速度选取的随意性。以 NA-CA0012翼型和某超临界翼型为对象,对新相似参数的有效性进行了数值仿真评估,结果显示,采用本文提出的相似参数及相应的试验参数确定方法,能够得到与参考条件一致的水滴收集率和结冰,初步说明新相似参数的是有效的,研究结果对于提高明冰及混合冰试验模拟的精度具有较好的参考价值。
Abstract:
The icing wind tunnel test is the main method for the aircraft icing research.The icing scaling law is the theoretical foundation of an icing wind tunnel test.To overcome the disad-vantage of current icing scaling method in glaze and mixing ice simulation,a new scaling parame-ter,CT,is proposed in this paper based on the analysis of heat transfer in icing process.This pa-rameter differs significantly from the scaling parameters originated from Messinger’s thermody-namic model for it take the effects of the phase change time into account.Introducing CT into the traditional scaling law can effectively avoid the randomness in selecting the test pressure and speed.The new parameter has been evaluated with numerical method based on the NACA0012 airfoil and a supercritical airfoil.The results show that on the two airfoils,both the ice shapes and the droplet collection efficiency under the reference icing conditions agree with those under the selected test conditions,which indicates that the parameter is feasible.The research work has good reference value for improving the accuracy of experimental simulation of glaze or mixing ice.
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