朝下网状镂空板壳结构临界沸腾换热研究

Study on Critical Boiling Heat Transfer of Downward Facing Surface with Reticular Hollow Shell Structure

摘要: 压力容器外部冷却(ERVC)是实现核电站堆芯熔融物滞留并限制放射性物质外泄的重要手段。在铜基体上制备了一种网状镂空板壳结构，开展了朝下网状镂空板壳结构表面在常压饱和去离子水中的临界沸腾换热实验研究。实验对比研究了不同材质(铜和不锈钢)和几何参数对网状镂空板壳结构表面沸腾性能的影响。研究结果表明：与光表面结构相比，网状镂空板壳结构表面临界热流密度(CHF)显著增大，增幅为67.9%~161.7%，具有较好的工程应用前景。朝下网状镂空板壳结构表面的CHF随着倾角的增加而明显增加。与铜光表面相比，不锈钢结构的壁面过热度显著增加，基本达到150℃以上，铜材质的网状镂空板壳结构较不锈钢结构具有更好的沸腾强化性能和更小的壁面过热度。

Abstract: External reactor vessel cooling (ERVC) is an important strategy for nuclear power plant to achieve the retention of molten materials in the reactor pressure vessel and limit the leakage of radioactive materials. A reticular hollow shell structure was prepared on a copper substrate, and critical boiling heat transfer experiments were conducted on the downward facing surface of reticular hollow shell structures in saturated deionized water at atmospheric pressure. The effects of different materials (copper and stainless-steel) and geometric parameters on boiling performance were conducted on the surface of reticular hollow shell structure. The research results show that the CHF of the reticular hollow shell structure surface is significantly increased compared with the smooth surface, with an CHF increase range of 67.9%~161.7%. With the inclination angle increases, the CHF on the downward facing surface of reticular hollow shell structure increases significantly. Compared with the copper plain surface, the wall superheat of stainless-steel structure significantly increases, basically reaching more than 150˚C. The reticular hollow shell structure made of copper has better boiling enhancing performance and smaller wall superheat compared to stainless steel structure.