Haoyu Wu1, Weimin Liu1, Xiaoming Li2, Fengyun Chen1 and Longbin Yang This email address is being protected from spambots. You need JavaScript enabled to view it.3

1The First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, P.R. China
2School of Chemical and Biological Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, P.R. China
3College of Power and Energy Engineering, Harbin Engineering University, Harbin 150001, P.R. China


 

Received: July 23, 2018
Accepted: December 17, 2018
Publication Date: June 1, 2019

Download Citation: ||https://doi.org/10.6180/jase.201906_22(2).0002  

ABSTRACT


Flash evaporation is extensively used in industrial application. In order to investigate flash evaporation, a new experimental system equipped with the high-speed CCD digital camera and data acquisition instruments is established. A series of experiments has been carried out with various initial temperatures from 50.0 C to 90.5 C, initial water heights of 400 mm to 550 mm, and superheats ranging from 1.5 K to 17.8 K. It is revealed that flashing phenomenon process includes three stages: bubbles generation stage, boiling growth stage and boiling reduction stage. Moreover, the heat transfer characteristics and flow mechanism of each stage has explored. In addition, a correlation between the propagation speed of flash evaporation wave and superheat degree was obtained. Results indicated that the intensity of flash evaporation drastically increases with the increasing of superheat.


Keywords: Flash Evaporation, Low Pressure, Flash Evaporation Wave, Propagation Speed, Visualization


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