Improved correlations of film boiling heat transfer for pool boiling of cryogenic fluid

To predict the heat transfer characteristics of cryogenic fluid film pool boiling, the experimental data concerning film pool boiling of cryogenic fluid are summarized and classified according to heater geometries. Then three typical film boiling heat transfer correlations, which include Bormley model, Frederking model and Breen & Westwater model, are validated, and their applicability and predictive accuracy in analyzing the film boiling heat transfer on different heater geometries are comparatively discussed. Following the validation study and correlation modification, a series of correlations for the heaters with different geometries are obtained to accomplish accurate prediction of the heat transfer characteristics of cryogenic fluid film pool boiling. It is found that in the precooling process of cryogenic system, the radiation heat transfer can be ignored due to its tiny proportion to the total heat transfer, while the geometry effect ought to be taken into consideration; for the heat transfer cylinder tube and sphere heaters, Bromley's and Frederking's correlations are suggested. For the plate and wire heaters, it is necessary to modify Frederking's and Breen & Westwater's correlations in terms of experimental data, and the deviations from the modified correlations are lower than 15%. © 2016, Editorial Office of Journal of Xi'an Jiaotong University. All right reserved.