ISSN Online: 2688-7231
ISBN Online: 978-1-56700-524-0
Proceedings of the 26thNational and 4th International ISHMT-ASTFE Heat and Mass Transfer Conference December 17-20, 2021, IIT Madras, Chennai-600036, Tamil Nadu, India
Influence of transient heat input on pool boiling behaviour
This work aims to investigate the effect of different transient heat inputs on pool boiling behavior. A CFD model is developed in ANSYS FLUENT 14.5 to carry out the study. Suitable user-defined functions are (UDF) used to implement different transient heat flux profiles in the simulation. The transient variations of heat flux are taken as sinusoidal variation, exponential variation, and linear variations, respectively, with a specific time period. The model is validated with Nukiyama's [1-2] heat flux vs. wall superheat or traditional pool boiling curve. Later it is validated with an experimental work that treated the heat flux as exponential variation with time. The effects of different transient heat flux on pool boiling behavior are investigated by comparing the volume fraction contours of vapor phase under similar bottom heat flux. Finally, the effects of different transient heat flux on heat flux vs. wall superheat curve and CHF point are investigated.