Steam condensation with existence of air is an important thermal hydraulic phenomenon in reactor containment. Previous investigations mostly focused on the surfaces of plates or tube bundles which are in parallel with the gas flow direction, and discussions on heat transfer surfaces with various inclination angles were merely restricted to plates. In addition, there is limited information about the condensation promotion effect caused by enlarged gas flow velocity at different tube inclination angles. To investigate the coupling effects of tube inclination and flow velocity, numerical simulations were carried on a 3 × 3 tube bundle. The local thermohydraulic profiles and heat transfer mechanism of steam condensation were analyzed carefully. The results indicate that the increase of inclination angle and flow velocity can dramatically promote condensation heat transfer. At the velocity of 0.3 m/s, the condensation heat transfer enhanced 327.8% as the tube bundle orientation changes from vertical to horizontal. At the inclination angle of 0°, the condensation heat transfer increased 223.2% as flow velocity increased from 0.3 m/s to 3 m/s. The inhibition effect and stack effect in tube bundle varied by the tube inclination and flow velocity.

空气中的蒸汽凝结是反应堆安全壳中重要的热力水力现象。先前的研究主要集中在与气体流动方向平行的板或管束的表面上，并且关于具有各种倾斜角的传热表面的讨论仅限于板。另外，关于在不同的管倾斜角度处由于气体流速增大而引起的凝结促进效果的信息有限。为了研究管倾角和流速的耦合效应，对3×3管束进行了数值模拟。仔细分析了蒸汽凝结的局部热工曲线和传热机理。结果表明，倾斜角和流速的增加可以显着促进凝结换热。在0.3 m / s的速度下，当管束的方向从垂直方向变为水平方向时，冷凝传热增强了327.8％。在0°的倾斜角下，随着流速从0.3 m / s增加到3 m / s，冷凝热传递增加了223.2％。管束的抑制效果和堆垛效果随管的倾斜度和流速而变化。