UNIT_14_REACTOR_CORE_反应堆堆芯.doc

UNIT 14 REACTOR CORE堆芯1. The reactor components consist of the fuel assemblies and all components which can be inserted into a fuel assembly to reactor power, power distribution or flow distribution. 堆内设备由燃料组件和所有容纳燃料的设备组成，用来产生功率、功率分配或流量分配。2. Fuel assemblies are square arrays (1717 or 1515) of long thin zircaloy tubes containing slightly enriched UO2 in the form pellets.燃料组件呈正方形排列(1717 或 1515)，外面是细长的锆合金管，内部是低富集度的UO2芯块。 3. Fuel assemblies are aligned by pins in the upper and lower core plates which mate with holes in the top and bottom nozzles. 燃料组件的定位是通过其上部和下部的芯板与上下管座上的管口配合来实现的。4. All control rod guide thimbles are filled with control rods, burnable poison assemblies, source assemblies or thimble plugging assemblies. 控制棒导向管内有控制棒，可燃毒物组件，源量程组件或阻力塞组件。5. A rod cluster control assembly consists of a group of individual neutron absorber rods fastened at top end to a common spider assembly. 每一控制棒组件内有一组独立的中子吸收体，它们的固定式通过底部和顶部的连接柄来实现。6. The absorber material used in the control rods is usually silver-indium-cadmium alloy sealed in stainless steel tubes. 通常用Ag-In-Cd合金作为控制棒吸收体的材料，吸收体被密封在不锈钢管中。7. Control rods are designed to respond to fast reactivity changes while slow changes such as fuel burnup are compensated by boron concentration changes.控制棒设计用来控制快的反应性变化，而慢的反应性变化如燃耗则用硼浓度来补偿。 8. The burnable poison assemblies are designed to provide a fixed discrete poison during the initial core load. 可燃毒物组件主要是在首次装料时提供固定的毒物（即负反应性，主要的原因是首次装料时剩余反应性较大）。9. To insure adequate indication for the operator during long-term reactor shutdown and during reactor startup, neutron source assemblies are installed in the core. 安装在堆芯的源量程组件作用：主要是在长期停堆和反应堆启动时给操纵员提供充分的指示。10. In order to limit core bypass through the control rod guide thimbles in fuel assemblies not containing control rods, sources assemblies, or burnable poison rods, the fuel assemblies at these locations are fitted with thimble plugging assemblies.为了限制堆芯的旁通流量，对于控制棒导向组件内不含控制棒、中子源、可燃毒物的组件用阻力塞组件。 11. Control rod drive mechanisms are magnetic jack assemblies which move control rods in discrete steps and tripping is accomplished by de-energizing the mechanisms and allowing the control rods to fall by gravity into the core. 控制棒驱动装置是磁力提升式，正常动棒是以一定的棒速，接到停堆指令时驱动机构失电，控制棒靠重力掉入堆芯。 12Reactor coolant enters the reactor vessel through the inlet nozzles, flows downward between the vessel wall and core barrel, then reverses direction and flows up through the core to remove the heat generated in the fuel assemblies, enters the upper ple