Affiliation:
1. Department of Mechanical and Aerospace Engineering, University of Central Florida , Orlando, FL 32816
Abstract
Abstract
Flow boiling heat transfer around the critical heat flux (CHF) condition at high reduced pressures of carbon dioxide in a 296-μm hydraulic diameter microchannel was experimentally studied. The CHF conditions for developing flow and fully developed flow were measured and compared to established correlations. The post-CHF heat transfer coefficient was obtained for l/d of 3.2, 7.4, and 11.6 for inlet Reynolds numbers, based on the homogeneous two-phase flow model, ranging from 6622 to 32,248. The critical heat flux conditions seemed to peak around a reduced pressure of about 0.5 and gradually decreased with reduced pressure. However, the typical rapid increase in the surface temperature following the CHF condition decreased with increasing pressure, and the post-CHF heat transfer coefficient was appreciably high (up to about 50 kW/m2K) at high reduced pressures. The enhancement in the heat transfer coefficient and CHF condition near the inlet were quantified. The experimental results were compared to established CHF correlations and heat transfer coefficient correlations with some limited success. Thus, the Katto CHF correlation (Katto and Ohno, 1984, “An Improved Version of the Generalized Correlation of Critical Heat Flux for the Forced Convective Boiling in Uniformly Heated Vertical Tubes,” Int. J. Heat Mass Transfer, 27(9), pp. 1641–1648) and the Bishop correlation (Bishop et al., 1964, “Forced-Convection Heat Transfer to Water at Near-Critical Temperatures and Supercritical Pressures,” Westinghouse Electric Corp, Atomic Power Division, Pittsburgh, PA.) for the post-CHF heat transfer coefficient were adjusted to better predict the experimental results. Additionally, an enhancement factor was derived to predict the increase in the heat transfer coefficient in the developing region.
Reference40 articles.
1. The ICECool Fundamentals Effort on Evaporative Cooling of Microelectronics;IEEE Trans. Compon., Packag. Manuf. Technol.,2021
2. Bubble Dynamics and Flow Boiling Instabilities in Microchannels;Int. J. Heat Mass Transfer,2013
3. Pressure Effects on Flow Boiling Instabilities in Parallel Microchannels;Int. J. Heat Mass Transfer,2009
4. Flow Boiling Instabilities in Microchannels and Means for Mitigation by Reentrant Cavities;ASME J. Heat Mass Transfer-Trans. ASME,2008
5. Review of Channel Flow Boiling Enhancement by Surface Modification, and Instability Suppression Schemes;Int. J. Heat Mass Transfer,2020
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献