球床式高温气冷堆的余热不确定性分析

反应堆在停堆后相当长时间内仍具有较高的剩余发热是核电站的重要特性，也是核电站安全分析的关键。因此，对反应堆余热及其不确定性进行分析，对于合理设计余热排出系统、研究论证燃料元件在事故后的安全特性等均具有重要意义。本工作结合德国针对球床式高温气冷堆制定的余热计算标准，介绍了球床式高温气冷堆剩余发热及其不确定性的计算方法，并结合200 MWe球床模块式高温气冷堆示范工程（HTR-PM）的初步物理设计，对长期运行在满功率平衡堆芯状态下的反应堆停堆后的余热及其不确定性进行了计算分析，为进一步的事故分析提供依据。

Uncertainty Analysis on Decay Heat of Pebble-bed High Temperature Gas-cooled Reactor

The large amount of decay heat in a quite long time after reactor shutdown, which is an important characteristic of the nuclear power plants, should be considered seriously during the safety analysis. Therefore, the study on the decay heat and its uncertainty analysis play an important role in the design of decay heat removal system, as well as in the safety verification of the fuel element during the accident. In referenced to the standard of Germany entitled “Decay Heat Power in Nuclear Fuels of High-temperature Reactors with Spherical Fuel Elements” especially for pebble-bed high temperature gas-cooled reactor (HTGR), the calculation method of decay heat and its uncertainty of pebble-bed HTGR were introduced. On the basis of the preliminary physical design of Chinese 200 MWe high temperature gas-cooled reactor pebble-bed module (HTR-PM), the decay heat and its uncertainty after reactor shutdown from long-term operation at rated power were analyzed, so as to provide a basis for further accident analysis.