铅铋共晶合金流动传热特性及不溶性腐蚀产物沉积特性数值模拟

Numerical Simulation of Heat-transfer and Insoluble Corrosion Product Deposition in Lead-bismuth Eutectic Alloy

  • 摘要: 作为ADS次临界堆首选的冷却剂材料,铅铋共晶(LBE)合金中出现微小颗粒物会威胁反应堆安全,同时缩短反应堆的使用寿命。为此,利用FLUENT软件对矩形通道中不溶性腐蚀产物的沉积分布进行了模拟研究。对连续相采用标准k-ε模型预测湍流变化,对颗粒相采用离散相模型(DPM)跟踪颗粒运动轨迹。研究发现,沉积效率与流体和冷壁之间的温差呈正相关;近壁面是颗粒物的高浓度区、低温区,这种分布有利于颗粒物在壁面上的沉积;近壁面是高湍动能区,不利于颗粒物沉积。受到壁面边界层影响,出现二次流现象,即在径向上出现8个对称的径向循环区域。

     

    Abstract: As the primary coolant of ADS (accelerator driven sub-critical system), the safety of reactor will be threatened and the lifetime of the reactor will be shortened by appearing of the tiny particles in LBE (lead-bismuth eutectic) alloy. To this end, numerical simulation with the code of FLUENT was used to research the deposition distribution of insoluble corrosion products in rectangular channel. The standard k-ε model was selected to predict the turbulence variation in the rectangular channel. The discrete phase model (DPM) was used to track the trajectory of the particles. It is found that the deposition efficiency is positively correlated with the temperature difference between the fluid and cold wall. The near wall region with a high concentration of particulate matter and low temperature is in favor of particulate matter deposition on the wall. At the same time, the high turbulence kinetic near wall region is not conducive to the deposition of particulate matter. A secondary flow phenomenon occurs under the influence of boundary wall, namely that there are eight symmetrical regions in the radial direction.

     

/

返回文章
返回