平板滞止区内饱和液体喷流沸腾的临界热流密度

Critical Heat-flux Density of the Jet Flow Boiling of a Saturated Liquid in a Flat-plate Stagnation Zone

对高温平板滞止区内饱和液体的圆形喷流冲击沸腾的临界热流密度进行了系统的稳态实验研究。考察了不同液体、流速和喷流直径等系统条件对喷流沸腾临界热流密度的影响。建立了一个预示临界热流密度的半理论半经验型方程,其基本形式采用过去的研究结果,方程系数由本研究的实验数据拟合得到。研究结果证明,饱和液体喷流冲击沸腾的临界热流密度取决于液体物性、滞止冲击速度和喷流直径。本研究得到的半理论半经验公式在广泛的实验范围内能很好的预示喷流沸腾的临界热流密度。

A systematic steady-state experimental study was conducted with respect to the critical heat-flux density of a round jet-flow impingement boiling of a saturated liquid in a high-temperature flat-plate stagnation zone. Investigated was the influence of the various system conditions, such as different liquids, flow velocities and jet flow diameter, etc. on the critical heat-flux density of the jet-flow boiling. A semi-theoretical and semi-empiric equation was established for forecasting the critical heat-flux density. The basic form of the equation was obtained by adopting available former research results. The coefficients of the equation were derived by a fitting of the experimental data of the present study. The study results indicate that the critical flow-flux density of the saturated fluid jet-flow impingement boiling depends on the physical properties of the liquid, stagnation impingement speed and jet flow diameter. By using the semi-theoretical and semi-empirical formula obtained as a result of the present study it is possible in a extensive range of tests accurately predict the critical heat-flux density of the jet-flow boiling.