垂直环形狭缝干涸后弥散流换热研究

以去离子水为工质的两相流体，当其由下向上流过电加热的同心环形套管时，对其进行了干涸后换热试验研究，用测量的试验数据拟合格罗尼费尔特（Groeneveld）和波洛米束（Polomik）公式，发现拟合出的系数存在较大分散度，表明该公式不适合狭缝中低质量流速的工况，采用多元线性回归方法，结合环形狭缝在内、外管分别加热的特点，引入了内、外管较大的热流密度与其平均值的比值，氦事出了新的换热公式，该公式与低质量流速下狭缝干涸后换热的试验数据符合得较好。

Post-Dryout Heat Transfer for Vertical Narrow Annular Channel

This investigation is conducted with deionized water flowed through a narrow annular channel that is heated electrically on the outside and inside under pressures of 1.5 MPa and 3.0 MPa and high temperature. The post dryout forced convective heat transfer was examined experimentally. The results show that the heat transfer behaviors in the annular gap is dissimilar to that in the convectional macro channels or tubes. Based on the experiment data, the Groeneveld equation and Polomik equation were developed. A heat transfer equation using the ratio of the bigger heat flux on inside and outside tube with the sum of them was developed. Results for low flow rate are compatible to the experiment data.