粗糙度对铁铬铝在骤冷过程中沸腾传热影响的实验研究

Experimental Investigation on Effect of Surface Roughness on Transient BoilingHeat Transfer of FeCrAl Quenched in Water

铁铬铝作为事故容错燃料包壳的主要候选材料,能够抑制反应堆在严重事故下产氢释能的风险,提高反应堆的事故耐受能力。本文基于可视化方法研究了不同粗糙度的铁铬铝在骤冷过程中沸腾传热行为,通过一维导热反问题求解计算铁铬铝的表面热流密度和温度,分析了液体过冷度和粗糙度对铁铬铝骤冷行为的影响。研究结果表明随着过冷度的增大,铁铬铝的骤冷时间减小,最小膜态沸腾温度增大。铁铬铝表面的膜态沸腾换热与粗糙度无关,最小膜态沸腾温度受表面亲水性影响显著。

FeCrAl is proposed as one of the candidate materials of accident tolerant fuel (ATF)cladding, which can suppress hydrogen generation under severe accident condition, and improve reactoraccident tolerance. In the present study, experimental investigation on the transient boilingheat transfer of FeCrAl with different surface roughness in quench process is conducted using visualizationmethod, and the effect of liquid subcooling and surface roughness on the quench behavioris analyzed. Based on the solution of 1-D inverse one-dimensional heat conduction problem, thesurface heat flux and temperature of FeCrAl during quenching process are calculated. It is foundthat as the liquid subcooling degree increases, the quenching duration of FeCrAl is decreased, andthe minimum film boiling temperature increases. The film boiling heat transfer is independent of thesurface roughness, and the minimum film boiling temperature is significantly affected by the surfacehydrophilicity.