海上摇晃条件下油轮货油温降规律数值模拟研究

摘要

Since the marine is subjected to rotational or/and translational motion,the essence of the thermal process is an unsteady-state mixed convection process accompanied with free liquid surface movement.This research investigates the movement of the free liquid surface and the characteristic of the temperature drop of the crude oil in the cabin when the tanker is subjected to rotational motion by dynamic-mesh VOF model based on FLUENT software.The research results indicate that the oscillation changes the direction of natural convection constantly,interrupting the strength of the natural convection.Meanwhile it leads to the motion of the free surface,causing the natural convection for the static case to become forced convection.These two effects significantly enhanced the temperature drop rate.It is found out that the temperature drop rate is positively related to the rotational angular velocity.This research will provide theoretical reference for the formulation of the oil heating scheme for tanker cargo.%油轮在海上运输过程中会发生旋转运动和平移运动,货油温降过程为伴随着自由液面运动的非稳态混合对流过程,水热力规律较静止情况更为复杂.基于FLUENT动网格的V()F模型对摇摆(旋转运动)条件下的原油自由液面运动规律及舱内货油温降规律进行系统研究.结果表明,摇摆一方面不断改变浮升力相对于船舱的方向,使得自然对流不断被扰动;另一方面导致自由液面与船舱内壁及舱内顶部空气间的相对运动,使静止条件下的自然对流变成强制对流.以上两方面的影响均对舱内原油与舱外海水间的传热产生了显著的强化作用,使得温降速率与旋转角速度呈正相关.