失水事故(lose of coolant accident,LOCA)试验中极端热冲击测试作为核设备安全检测中的关键测试之一,能够模拟LOCA事故中高温高压蒸汽对核设备造成的损害程度和设备运行工况的影响情况。在LOCA试验过程中的温度变化对热冲击实验研究尤...失水事故(lose of coolant accident,LOCA)试验中极端热冲击测试作为核设备安全检测中的关键测试之一,能够模拟LOCA事故中高温高压蒸汽对核设备造成的损害程度和设备运行工况的影响情况。在LOCA试验过程中的温度变化对热冲击实验研究尤为重要,实际测试中很难测量出整个压力容器中的温度变化,需要在整个环境中多点布置温度传感器才能测得。如何分析极端温度冲击下的压力容器温度场分布和优化传感器布局成为LOCA测试系统的关键问题。因此采用ANSYS Fluent软件对LOCA热冲击测试环境进行仿真模型,提取极端热冲击的瞬态参数,验证实验仓内流体运动状态和紊流情况,研究测试环境中温度分布特性和温度传感器摆放位置。在仿真测试中LOCA仿真模型中试验品表面温度与实际测试环境表面温度偏差小于2℃,仿真模型符合实际测试需求。展开更多
Xizhang trench is located 10 km northwest of Taiyuan city, Shanxi Province, in front of a NNW-trending scarp of 4.6m height on the northern segment of the Jiaocheng fault zone. The dimensions of the trench are 108m in...Xizhang trench is located 10 km northwest of Taiyuan city, Shanxi Province, in front of a NNW-trending scarp of 4.6m height on the northern segment of the Jiaocheng fault zone. The dimensions of the trench are 108m in length, 8m in width, and 10m in depth. There are 18 horizons revealed in the trench. The upper strata are sandy loam; the upper strata of the downthrown block of the fault are gravels, the lower ones are an interbed of brown loam and sandy loam. The strata on the upthrown block of the fault are sandy loam containing gravel. The trench shows 3 fault planes, and the upper offset point on the fault plane is 1.5m below the ground surface, the newest dislocated stratum is （3.74±0.06） ka BP. The trench reveals a lot of deformation traces, such as fault planes, dislocated strata, colluvial wedges and formation tilting. The relationship between strata and faults in the trench shows that 3 paleoearthquake events have occurred at the Jiaocheng fault zone since the Early Holocene, they are about （3.74±0.06）- （3.06±0.26）ka BP, （8.35±0.09）ka- （3.74±0.06）ka BP, and（ 10.66±0.85） - （8.35±0.09）ka BP. The average interval among the events is 2.6 - 3.6ka. The minimum coseismic vertical displacements of the 3 events are 3.0m, 2.5m and 3.2m, respectively. The significance of Xizhang trench is that the Jiaocheng fault used to be active thousands of years ago, though there is no M ≥ 7.0 earthquake recorded in historical documents. Evidence of new Jiaocheng fault zone activity during the Holocene is important for the earthquake safety assessment of Taiynan city in the future.展开更多
文摘失水事故(lose of coolant accident,LOCA)试验中极端热冲击测试作为核设备安全检测中的关键测试之一,能够模拟LOCA事故中高温高压蒸汽对核设备造成的损害程度和设备运行工况的影响情况。在LOCA试验过程中的温度变化对热冲击实验研究尤为重要,实际测试中很难测量出整个压力容器中的温度变化,需要在整个环境中多点布置温度传感器才能测得。如何分析极端温度冲击下的压力容器温度场分布和优化传感器布局成为LOCA测试系统的关键问题。因此采用ANSYS Fluent软件对LOCA热冲击测试环境进行仿真模型,提取极端热冲击的瞬态参数,验证实验仓内流体运动状态和紊流情况,研究测试环境中温度分布特性和温度传感器摆放位置。在仿真测试中LOCA仿真模型中试验品表面温度与实际测试环境表面温度偏差小于2℃,仿真模型符合实际测试需求。
基金sponsored by the program of "ActiveFault Test Detectionin City" of the National Development and Reform Commission,PRC.
文摘Xizhang trench is located 10 km northwest of Taiyuan city, Shanxi Province, in front of a NNW-trending scarp of 4.6m height on the northern segment of the Jiaocheng fault zone. The dimensions of the trench are 108m in length, 8m in width, and 10m in depth. There are 18 horizons revealed in the trench. The upper strata are sandy loam; the upper strata of the downthrown block of the fault are gravels, the lower ones are an interbed of brown loam and sandy loam. The strata on the upthrown block of the fault are sandy loam containing gravel. The trench shows 3 fault planes, and the upper offset point on the fault plane is 1.5m below the ground surface, the newest dislocated stratum is （3.74±0.06） ka BP. The trench reveals a lot of deformation traces, such as fault planes, dislocated strata, colluvial wedges and formation tilting. The relationship between strata and faults in the trench shows that 3 paleoearthquake events have occurred at the Jiaocheng fault zone since the Early Holocene, they are about （3.74±0.06）- （3.06±0.26）ka BP, （8.35±0.09）ka- （3.74±0.06）ka BP, and（ 10.66±0.85） - （8.35±0.09）ka BP. The average interval among the events is 2.6 - 3.6ka. The minimum coseismic vertical displacements of the 3 events are 3.0m, 2.5m and 3.2m, respectively. The significance of Xizhang trench is that the Jiaocheng fault used to be active thousands of years ago, though there is no M ≥ 7.0 earthquake recorded in historical documents. Evidence of new Jiaocheng fault zone activity during the Holocene is important for the earthquake safety assessment of Taiynan city in the future.
