人造冻云是飞机强度全天候实验室的必备研究项目。根据美国航空管理局FAA附录C中的规定,人造冻云的液态水含量为0 ~ 3.0 g/m3,中值直径为15 ~ 50 μm。本文对我国飞机强度全天候重点实验室拟选用的内混式空气助力孔式喷嘴的雾化特性进行了测量。研究了不同空气助力压力、不同水流量和不同喷嘴结构尺寸对宏观和微观喷雾特性及液态水含量的影响,提出了改善雾化质量以满足人造冻云要求和优选喷嘴的方法。结果表明：喷雾锥角越大、空气助力压力越高、水流量越小、喷嘴尺寸越大,则雾化水滴颗粒越小、雾化质量越好。
Artificial freezing cloud test is an essential research project for an all-weather laboratory of the aero-plane intensity. According to FAA Appendix C, a range of liquid water content in air for artificial freezing cloud is 0 ~ 3.0 g/m3; a range of middle diameter in spray is 15 ~ 50 μm. Atomization characteristics of the air assistant hole nozzles intended by all-weather key laboratory of the aero-plane intensity in China are measured. It is investigated that macroscopic and microcosmic spray characteristics and liquid water content in air are influenced by various air assistant pressures, water flow rates and atomizer sizes. Some specific methods of improving spray quality are proposed to satisfy the condition of artificial freezing cloud and selective preference atomizers. The results show that spray quality can be improved and water droplet size be reduced by larger spray angle, higher air assistant pressure, lower water flow rate, and larger nozzle size
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