纵向涡发生器对矩形窄通道内对流换热的影响

Effect of Longitudinal Vortex Generators on Convective Heat Transfer in Rectangular Narrow Channel

针对反应堆堆芯板状燃料元件冷却通道内的强化传热问题，对带有周期性分布纵向涡发生器（I．VGs）的水平矩形窄通道内的流动与换热进行了实验研究，得出了雷诺数在3×10^3～2×10^4的范围内LVGs安装形式（一侧带LVGs或两侧带I．VGs）对水的流动与换热特性的影响规律．结果表明：带有周期性分布LVGs通道的平均努谢尔数比光通道的高25％～35％，但阻力系数也比光通道的高．在3种不同比较准则（相同质量流量、相同压降及相同泵功）下，两侧带同向I．VGs通道的综合性能好于单侧带有LVGs通道的综合性能．I．VGs能够破坏热边界层，带走更多的热量，从而降低板状燃料元件的温度和堆芯的烧毁率．

To enhance heat transfer in cooling channel of plate type fuel element in reactor core, the experimental research on heat transfer and flow in a horizontal rectangular narrow channel with periodically mounted longitudinal vortex generators （LVGs） with water was carried out. The effect of LVGs mounting patterns on flow and heat transfer performance was investigated within the range of Reynolds number from 3 ×10^3 to 2×10^4. It was found that the average Nusselt number in the channel with periodically mounted LVGs is higher than that in the smooth channel by 25% to 35%, and the pressure drop in the former gets more remarkable than that in the latter. The comparisons of thermal performance under three constraints （identical mass flow, identical pressure drop and identical pumping power） indicate that the overall heat transfer performance of the channel with mounted LVGs on two sidewalls is better than that of the channel with mounted LVGs on one sidewall. Channels with LVGs can be used to lower the temperature of plate type fuel element and burnout probabilitv of the reactor core.