Study on SLD icing test in icing wind tunnel

Based on the performance of the existing spray system in the FL-61 icing wind tunnel, the freezing drizzle conditions with certain conformity with the drop diameter distribution specified in Appendix O were realized, and the icing tests of freezing drizzle conditions of unimodal and bimodal drop diameter distributions and different drop diameter distributions of similar MVD were carried out. The results show that the large droplet cloud plays a dominant role in the leading edge icing and determines the ice shape and icing range in the freezing drizzle environment; The drop diameter distributions is diverse in SLD environment, It was found that a difference of 1 μm in MVD led to a clear difference in the ice shape of the leading edge. Therefore, for the description of SLD icing environment, in addition to paying attention to the ambient temperature, MVD, and LWC, it is also necessary to consider the drop diameter distribution.