| Considering the relationship between the phenomena of critical heat flux (CHF) and the safety of nuclear reactor, the research of CHF on experiment and theory has been carried in detail. By now, many achievements have been acquired, including hundreds of empirical correlations to predict the CHF value, and models for CHF in different conditions, what's more, more basic research about two-phase flow, heat transfer, and behavior of gas bubble etc. Whereas, all approach of predicting CHF value or explaining the phenomena, has disadvantages of limited parameter range and accuracy. Therefore, sequential research on CHF is necessary.Limiting quality is a CHF phenomena of Annular Flow ,which means CHF increasing sharply with the quality increasing. This article mainly carries out research on such phenomena.Based on theoretical investigations to the critical heat flux of annular flow in limiting quality regime (LQR), the Whalley model is solved numerically and the adaptability of the model in LQR is analyzed. Fatherly, a physical model of critical heat flux used to the flow round tube is developed.What's more, based on existing knowledge on mechanism of such CHF phenomena and mass and heat transfer insuch conditionsnumerical calculation method to predict the CHF value inthis article provides asuch condition. Compared with some other major physical models, Prediction results show that the physical model works very well with a relatively high accuracy.In the last section of this article, many correlations, including Biasi correlation,CISE correlation, and 1996 Look-up Table, are compared with our experimental data. Based on these results, evaluations on these correlations are provid.214 data achieved in this experiment comes from the CHF data-base of the University of Ottawa .The pressure, velocity , inlet quality, diameter and length of the round tube are in the rang: p = 999?19610kPa, G = 490-5016.6kg/m~2·s, X =0. 199?0.869, D = 0. 00578?0.0108m, Lh = 0. 78-10.94m。...
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