锥形结构表面核态沸腾数值模拟研究

Numerical Simulation of Nucleate Boiling on Conical Surfaces

摘要: 采用最近提出的格子Boltzmann方法，在具有规则排列的锥形结构表面模拟了核态沸腾。结果表明，在锥形结构的表面，障碍物角点处的液体先发生相变，相变只会发生在障碍物形成的凹槽内及角点处。与矩形结构表面相比，在锥形结构表面形成的气泡会完全从壁面脱离。另一方面，对比了不同表面结构间距和结构尺寸对气泡生长和传热性能的影响。当结构间距较大时，气泡从壁面脱离较早，壁面的核态沸腾换热性能较好，也具有较高的临界热流密度。当结构尺寸较大时，气泡从壁面脱离较晚，壁面换热性能变差，临界热流密度减小。

Abstract: The lattice Boltzmann model is used to simulate nucleate boiling on a conical surface with regular arrangement. The results show that on the conical structure surface, the phase change process occurs firstly at the corners and in the grooves of the obstacle, and does not take place on the obstacle surface. In contrast to the rectangular surface, bubbles which appear on the conical surface completely depart from the wall. On the other hand, the effects of different surface structure space and structure size on bubbles growth and heat transfer performance are compared. For the large structure space, bubbles depart from the wall earlier, the nucleate boiling heat transfer performance is better, and the critical heat flux is higher. For the large structure size, bubbles depart from the wall later, the heat transfer performance becomes worse, and the critical heat flux decreases.