锅炉的安全性校核是新锅炉设计的一个关键性问题.针对东方锅炉股份有限公司新设计的600 MW超临界CFB锅炉,采用大涡紊流模型数值模拟了锅炉内非定常含灰气流流动,并对锅炉内压强波动进行了频谱分析.为减小本数值模拟的巨大计算量,提出了等效密度模型以简化真实的含灰气流,其相应等效密度参数通过设计及实验数据进行拟合.锅炉内的压力分布及其波动规律是吊挂中隔墙动力学安全性校核的基础,分析结果为吊挂中隔墙在表面压力载荷下的动态响应提供了载荷条件. Boiler safety check is a key issue of new boiler design.Aiming at the new design of 600 MW supercritical CFB boiler of Dongfang Boiler Co., the large eddy turbulence model is used to numerically simulate unsteady flow of ash-containing gas in the boiler, And the spectrum analysis of the pressure fluctuation in the boiler was carried out.In order to reduce the huge amount of calculation of this numerical simulation, an equivalent density model was proposed to simplify the real ash-containing gas flow, and the corresponding equivalent density parameters were fitted by design and experimental data The pressure distribution and its fluctuation in the boiler are the basis of the dynamic safety check of the middle wall of the hanging wall. The analysis results provide the load conditions for the dynamic response of the middle wall of the hanging wall under the surface pressure load.