结冰风洞液态水含量测量装置设计与实现

Design and implementation of the device for liquid water content measurement in icing wind tunnel

结冰风洞与常规风洞的重要区别就是结冰风洞能够模拟真实大气结冰云雾环境,研究飞行器的结冰特性,因此结冰云雾参数的模拟是结冰风洞主要而且关键的能力。液态水含量是结冰风洞云雾参数中一项重要参数,其准确测量是结冰试验开展的基本前提。冰刀法测量液态水含量在国内外被广泛认可,且冰刀装置作为风洞校测基本手段,写入了结冰风洞校准规范。针对结冰风洞中用于液态水含量测量的冰刀装置,根据其测量原理制定了试验方案;提出了整套装置设计的技术指标并指出其中的技术难点;对总体结构进行了设计,并对关键受力部件进行了强度、刚度分析;进行了关键技术研究,包括冰刀液态水收集系数计算和驱动控制系统设计等;最后将设计出的冰刀装置在结冰风洞中进行了试验验证。试验结果表明:冰刀装置设计合理,液态水收集效果良好,实现了结冰风洞液态水含量的测量标定,且防护罩开闭迅速,实现了结冰时间的精确控制,满足技术指标要求。

One important difference between icing wind tunnel and conventional one is that icing wind tunnel can simulate the real atmospheric cloud icing environment,and aircraft icing features can be studied in icing wind tunnel.As a result,the simulation of icing cloud parameters is the key function of icing wind tunnel.Liquid water content is one of the important parameters.Accurate measurement for the liquid water content is an essential prerequisite for freezing tests to be carried out.Icing blade is widely recognized at home and abroad as an important method measuring liquid water content.Moreover,icing blade is used as a basic tool for calibrating specification of icing wind tunnel.In this paper,the principle has been introduced for the utilization of icing blade to measure liquid water content in icing wind tunnel,and test plans have been formulated;technical targets have been proposed for the design of a complete set of device,and technical difficulties within the design have also been pointed out;the overall structure of device has been designed,and the stiffness and strength of key mechanical parts has been analyzed;the key technique of the device design has been introduced in detail,including the calculation of collection coefficient for liquid water content and the design of driving control system;the designed icing blade is tested in the icing wind tunnel.The application results show that the icing blade has a good collection effect of liquid water.The protection cover has a high opened and closed speed,which can be realized as accurate control of freezing time.The designedicing blade can fulfill technical target and successfully measure the liquid water content.