Numerical Analysis of Deterioration in Heat Transfer to Supercritical Water
Numerical Analysis of Deterioration in Heat Transfer to Supercritical Water
复制标题
超临界水传热恶化的数值分析
DOI：
10.1299/kikaib.60.2497
复制
发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Y. Oka
中科院分区：
文献类型：
--
作者：
S. Koshizuka;N. Takano;Y. Oka
使用 k-e 模型对超临界水传热的恶化进行了数值研究。物理属性被视为变量并从蒸汽表库中计算。数值结果与Yamagata等人的实验数据一致。 [翻译。 JSME，38-2(1972)]发现传热恶化是由两种取决于流量的机制引起的。在大流量的情况下，靠近壁面的传热减少，由于热通量，流体特性局部改变。在小流量的情况下，浮力使流速分布变得平坦，湍流传热减少。目前的分析表明，超临界热水力学可以用单相湍流流体动力学来解释。
Deterioration in heat transfer to supercritical water is numerically studied using a k-e model. Physical properties are treated as variables and calculatd from the steam table library. The numerical result agrees with the experimental data of Yamagata et al. [Trans. JSME, 38-2(1972)]It is found that heat-transfer deterioration is caused by two mechanisms depending on the flow rate. In the case of large flow rate, heat transfer is reduced near the wall where the fluid properties are locally changed due to the heat flux. In the case of small flow rate, buoyancy force flattens the flow velocity distribution and the turbulent heat transfer is decreased. The present analysis shows that supercritical thermal hydraulics can be explained by the single-phase turbulent fluid dynamics.