The prediction of droplet size distribution is always based on water droplet collision outcome at room temperature, which has a great difference with that in freezing environment. Because of this, the outcome of binary water droplet collisions was investigated experimentally within a certain temperature range. Two monodisperse droplet chains were produced by means of piezoelectric droplet generators and two high speedcameras were used to observe the collision process. Values of the Weber number based on the small droplet sizes are from 0 to 100. Droplet temperature varies from 25℃ to －5℃. Compared with the outcome at room temperature, the result of the supercooled water droplet collision has obviously changed. ① The coalescence region extends to the separation region. ② The reflexive separation region move towards the region with high Weber number value. ③ The stretching separation region is slightly shifted downward. From the perspective of the supercooled water properties, the influence of temperature on collision results was discussed. The droplet size distribution of supercooled spray has a great difference with the result based on water droplet collision at room temperature.
YIN Jinge1，KONG Weiliang1，WANG Fuxin1， LIU Hong1，YANG Kun2
. Experimental Investigation of Binary Supercooled
Water Droplet Collision [J]. Journal of Shanghai Jiaotong University, 2017
, 51(8)
: 939
-945
.
DOI: 10.16183/j.cnki.jsjtu.2017.08.007
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