结冰云雾参数对冰与固壁间剪切强度影响的初步研究

基于结冰风洞实验段,建立了冰与固壁间黏附界面剪切强度测量实验装置,获得了合理的剪切强度范围。在0.3 m×0.2 m结冰风洞实验段内开展了冰与固壁间黏附界面剪切强度的测量实验。掌握了结冰环境温度、平均水滴直径等结冰云雾参数对冰与固壁间黏附剪切强度的影响规律。研究表明:结冰环境温度为-15~-10 ℃间出现了剪切强度极大值。来流速度越大,水滴的惯性力越大,水滴间的间隙越容易被填充,冰与固壁间剪切强度也就越大。平均水滴直径(MVD)为35 μm附近出现了剪切强度极小值,水滴直径越小,水滴之间的间隙就越小,结冰就越致密。水滴直径越大,水滴越容易发生平铺,水滴之间的间隙就容易被填充,反而造成剪切强度增大。 

Preliminary study on influence of icing cloud parameters on ice shear strength on solid wall

The ice shear strength test equipment was established in the test section of icing wind tunnel, and used to measure the shear strength between ice and solid wall of airplane. The reasonable range of ice shear strength was obtained. The ice shear strength measurement was implemented in test section of 0.3 m×0.2 m icing wind tunnel. The influences of icing cloud parameters on the ice shear strength between ice and solid wall were obtained. Research showed that the maximum value of ice shear strength appeared when the icing environmental temperature was between -15 ℃ and -10 ℃. The higher airflow speed indicated the larger impact force of droplets on solid wall. The gap among droplets was easier to be filled in. Thus, the ice shear strength was increased. The minimum value of ice shear strength happened when the mean volume diameter (MVD) of droplets was near 35 μm. The ice became compact and the gap among droplets was smaller along with the decrease of MVD. And the droplets easily spread out and were difficult to be frozen immediately. The ice shear strength increased due to the filling of gap among droplets.