Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
658353 | International Journal of Heat and Mass Transfer | 2013 | 11 Pages |
Abstract
In the part I, the OHP simulations with and without the TS bubble generation have been performed. In those simulations, four fitting and six design parameters were used. In this paper, the effects of both design and fitting parameters are investigated in the simulations with and without the TS bubble generation. The fitting parameters are the coefficient of phase change (α), evaporation coefficient on the TS bubble (αb), initial length of the TS bubble (Lb) and degree of superheat (ÎTsup). The design parameters are the nucleation site (NS) configurations, NS positions, number of NSs, temperature of heating section, number of liquid slugs and vapor plugs, and number of turns. The results show that both the fitting and design parameters influence the motions of liquid slugs and vapor plugs, pressure difference between two vapor plugs (driving force) and heat transfer rates of an OHP. The effects of the combinations of design parameters are also investigated. The results show that the motions of liquid slugs and vapor plugs becomes complex (unsteady oscillating motions) due to the random TS bubbles generation. The profile of heat transfer rates also becomes random due to the complex motions.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Fluid Flow and Transfer Processes
Authors
Raffles Senjaya, Takayoshi Inoue,