Subcooled nucleate boiling

Predictions of the effect of subcooling With experimental results of subcooled nucleate boiling CHF for liquid metals lacking, the "ritsub can only be estimated by Kutateladze s equation (1952),... 

Partial nucleate flow boiling of ordinary liquids Bergles and Rohsenow (1964), using data obtained from several commercially finished surfaces, have developed a criterion for the incipience of subcooled nucleate boiling by solving graphically the... 

Subcooled nucleate boiling is frequently called local boiling or surface boiling. 

BankofT, S. G., and R. D. Mikesell, 1959, Bubble Growth Rates in Highly Subcooled Nucleate Boiling, Chem. Eng. Prog. Symp. Ser. 55(29) 95—102. (2)... 

Bibean, E. L., and M. Salcudean, 1994, A Study of Bubble Ebullition in Forced Convective Subcooled Nucleate Boiling at Low Pressures, Int. J. Heat Mass Transfer 37(15) 2245 2259. (4)... 

The onset of nucleate boiling (line XX in Fig. 15.88) occurs above the x = 0 line at low heat flux (i.e., there is a net bulk superheat of the liquid) but at qualities less than 0 for high heat fluxes, corresponding to the region of subcooled nucleate boiling. For heat transfer to a single-phase liquid, the wall superheat (ATsat)w can be calculated from... 

Y. Miyasaka, S. Inada, and Y. Owase, Critical Heat Flux and Subcooled Nucleate Boiling in the Transition Region Between a Two-Dimensional Water Jet and a Heated Surface, J. Chem. Eng. Japan, 13, pp. 29-35,1980. 

The core coolant/moderator must remain single phase (not even subcooled nucleate boiling) should occur. 

For these calculations it was assumed that boiling within the core is to be avoided that is, the core coolant/moderator must remain single phase (not even subcooled nucleate boiling should occur). Given this restriction, the core-power/core-outlet-temperature combinations given in bold in Table 5.3 are eliminated as possible viable operating conditions. 

During the subcooled nucleate flow boiling of a liquid in a channel the bulk temperature of the liquid at ONB, 7b, is less than the saturation temperature, and at a given value of heat flux the difference ATsub.oNB = 7s - 7b depends on L/d. The experimental parameters are presented in Table 6.2. 

Kandlikar SG, Mizo V, Cartwright M, Ikenze E (1997) Bubble nucleation and growth characteristics in subcooled flow boiling water. National Heat Transfer Conference HTD-342. ASME, New York, pp 11-18... 

Liu Z, Winterton RHS (1991) A general correlation for saturated and subcooled flow boiling in tubes and annuli, based on a nucleate pool boiling equation. Int J Heat Mass Transfer 34 2759-2766... 

Judd (1989) interpreted experimental results of Ibrahim and Judd (1985), in which the bubble period first increased and then decreased as subcooling varied over the range 0 < (7 t - Tm) < 15°C (27°F), by means of a comprehensive model incorporating the contributions of nucleate boiling, natural convection, and microlayer evaporation components. The mechanism responsible for the nucleation of bubbles at exactly the frequency required at each level of subcooling is the subject of their continuing research. 

For diabatic flow, that is, one-component flow with subcooled and saturated nucleate boiling, bubbles may exist at the wall of the tube and in the liquid boundary layer. In an investigation of steam-water flow characteristics at high pressures, Kirillov et al. (1978) showed the effects of mass flux and heat flux on the dependence of wave crest amplitude, 8f, on the steam quality, X (Fig. 3.46). The effects of mass and heat fluxes on the relative frictional pressure losses are shown in Figure 3.47. These experimental data agree quite satisfactorily with Tarasova s recommendation (Sec. 3.5.3). 

The relationship between the wall temperature and the coolant temperature can be seen in Figure 4.5. The wall temperature starts to bend at the incipience of subcooled boiling, where the coolant temperature is defined as Tm. The wall temperature follows a curve of partial boiling and then reaches an approximately constant value at a fully developed nucleate boiling where the coolant temperature... 

In a subcooled Freon flow, Tong (1972) caught a front view of a heating surface with nucleate boiling and film boiling existing simultaneously on the same... 

Dean, R A., R. S. Dougall, and L. S. Tong, 1971, Effect of Vapor Injection on Critical Heat Flux in a Subcooled R-l 13 (Freon) Flow, Proc. Int. Symp. on Two-Phase Flow Systems, Haifa, Israel. (6) Deane, C. W., and W. M. Rohsenow, 1969, Mechanism and Behavior of Nucleate Boiling Heat Transfer to the Alkali Liquid Metals, USAEC Rep. DSR 76303-65, Massachusetts Institute of Technology, Cambridge, MA Also in 1970, Liquid Metal Heat Transfer and Fluid Dynamics J. C. Chen and A. A. Bishop, Eds., ASME Winter Annual Meeting, New York. (4)... 

Ibrahim, E. A., and R. L. Judd, 1985, An Experimental Investigation of the Effect of Subcooling on Bubble Growth and WaitingTime in Nucleate Boiling, Trans. ASME, J. Heat Transfer 707(1) 168... 

Liu, Z., and R. H. S. Winterton, 1991, A General Correlation for Saturated and Subcooled Flow Boiling in Tubes and Annuli Based on a Nucleate Pool Boiling Equation, Int. J. Heat Mass Transfer 34(11) 2759 2766. (4)... 

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