Calculation method of gas-liquid two-phase boiling heat transfer in helically-coiled tube based on separated phase flow model

Helically-coiled tube has a vital effect on the heat transfer coefficient of the heat exchanger. The limitation of present research is that the correlation of boiling heat transfer in the helically-coiled tube has a certain scope of application. Separated phase flow model was developed to establish a calculation method for gas-liquid two-phase boiling heat transfer in helically-coiled tube. Viscous force, gravity and centrifugal force were used to solve gas-film velocity, gas-film thickness and heat transfer coefficient. Then the calculation model was corrected by considering the influence of the flow pattern and wall superheat. The calculated results were compared with experimental results obtained from opening literature. Results show that the error between the calculated value and the experimental value is in the range of 32% and 41%. The error between the corrected value and the experimental value is located in 9% and 20%. The calculation model shows excellent predictive capability for gas-liquid two-phase boiling heat transfer in helically-coiled tube. (C) 2020 Elsevier Ltd. All rights reserved.