长期冷却再循环阶段AFA-3G燃料组件碎渣堵塞实验研究

AFA-3G Fuel Assembly Blockage Test Research During Long Term Core Cooling

针对M310堆型在长期冷却再循环阶段碎渣对AFA-3G燃料组件的压损影响开展了实验研究。通过实验获得了存在碎渣堵塞和化学效应影响条件下、燃料组件的阻力变化特性。实验结果表明:在长期冷却再循环初期,地坑过滤器表面碎渣床未形成之前,碎渣穿过地坑过滤器在燃料组件上沉积导致燃料组件压损显著增大;随着地坑过滤器表面碎渣床逐渐形成,过滤器压损逐渐增大,同时燃料组件压损开始逐渐降低;随着地坑介质温度的逐步降低,化学效应影响产生,生成的化学沉淀物在物理碎渣床上沉积导致燃料组件压损进一步增大;在长期冷却再循环后期,燃料组件压损趋于稳定。

A AFA-3G fuel assembly blockage test research during LTCC(long term core cooling)after LOCA is been proceeded.Based on the test,pressure loss of AFA-3G fuel assembly which includes debris deposition and chemical effect has been got.From the test result,at the beginning of LTCC,before the formation of debris bed on sump strainer,debris passes through the sump strainer and deposits on the fuel assembly,which causes significant increase in pressure loss of fuel assembly.Following the formation of debris bed on sump strainer,pressure loss of sump strainer starts to increase and pressure loss of fuel assembly decreases.Following the sump temperature decreasing,chemical effect occur,the deposition of chemical precipitation on physical debris bed results in gradual increase of pressure loss of fuel assembly.At the end of LTCC,pressure loss of fuel assembly tends to stable.