Transition experiment from dripping to jetting mode
WANG Zhentao1, XUE Jiayi1， KONG Qian1, LI Rui2, YANG Shiqi1, LI Bin1
1. School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013， China； 2. Leybold (Tianjin) International Trade Co., Ltd.， Tianjin 300000， China
Abstract：The liquid is discharged into the surrounding atmospheric environment through the nozzle or orifice with small inner diameter. When the outlet pressure or flow is increased, the flow mode of the liquid at the end of the capillary can change from periodic dripping (PD) to dripping faucet (DF) with latter jetting (J). Through changing the flow rate, three typical atomization modes of PD，DF and J for deionized water and ethanol were recorded by high-speed digital camera, and the critical Weber number of the transition of atomization mode was obtained. The results show that in the process of PD, the shape of droplets is gradually changed from spherical to pear-shape with the increasing of outer diameter of the orifice. As the flowrate is increased, two liquids are gradually reached the jetting regime from the dripping mode through the dripping faucet. Compared with deionized water, the transition of ethanol exists in small range and only in the inner diameter of 0.33-0.60 mm, and it is very easy to transition directly from periodic dripping to jetting regime. The difference of atomization mode transition between deionized water and absolute ethanol is caused by the different surface tension. The critical Weber number corresponding to the transition from dripping to jetting mode can realize the prediction of the atomization mode transition process.
王贞涛1， 薛佳怡1， 孔茜1， 李睿2， 杨诗琪1， 李彬1. 滴状向射流模式转变的试验研究[J]. 江苏大学学报（自然科学版）, 2024, 45(5): 544-550.
WANG Zhentao1, XUE Jiayi1， KONG Qian1, LI Rui2, YANG Shiqi1, LI Bin1. Transition experiment from dripping to jetting mode[J]. Journal of Jiangsu University(Natural Science Eidtion)
, 2024, 45(5): 544-550.
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2024, Vol. 45 
