某型直升机缩比模型着水试验研究

Research on the Ditching Test of a Dynamical-scaled Helicopter Model

为了研究直升机水上迫降特性,利用某民用直升机1∶8缩比模型,在TsAGI水动实验室开展了静水及规则波中的模型着水试验,测得了模型姿态、驾驶舱及重心处过载系数和模型底部压力时间历程曲线,采用"相对零位"方法进行了试验数据处理,得到了过载、压力峰值,并确定了直升机着水安全范围,给出了保证模型不倾覆的运动参数范围。试验数据分析表明:静水试验中,模型以俯仰角8°~10°前飞着水时,垂向过载较小;规则波试验中,模型以较小的前飞速度落在波峰或波背上,垂向过载较小。此项研究为国内开展直升机水上迫降试验研究提供了参考。

To investigate the ditching characteristics of the helicopter, the ditching test of a civil helicopter model was carried out in TsAGI towing tank. The scale of the model is 1 ： 8. The model was dropped in the calm water and the regular waves. During the test, the attitude, the overloads in the model fore part and the center - of - mass, the pressure in different part of the model bottom subject to time were measured. The algorithm of zero sampling was applied in the data processing and visualization, the peak values of overloads and pressures were obtained. The helicopter safe ditching range, namely, a combination of kinematic parameters under which the model ditches with- out overturning was determined. According to the test data analysis, the lower values of the normal overloads could be obtained when ditching at the trim angles of 8 - 10°on calm water and ditching on wave crest or on back wave at the minimum possible forward speed. The investigation provided some reference for the research on the helicopter ditching test in China.