The thermal radiation transfer was complex due to high pressure, complicated flue gas components and abundant particles in the dilute phase region of oxy-fuel combustion pressurized fluidized bed. To carry out the radiation heat transfer, numerical simulations were done based on weighted sum of gray gases model (WSGG) and Mie theory. The Radiation Transfer Equations (RTE) of bubbling fluidized bed and circulating fluidized bed was solved by discrete ordinate method (DOM). The radiation heat transfer of fluidized bed under air combustion was verified and then the simulations were accomplished under pressurized oxy-fuel combustion hypothesis. The results revealed that the particle radiation was still dominant under pressurized oxy-fuel combustion. The change of total pressure and gas composition had slight effects on the radiation heat transfer in the fluidized bed. The gas radiation described by the new pressurized WSGG model and RTE solving by body-fitted coordinate system were much accurate to simulate radiation heat transfer. All the results were significant to provide theoretical basis of designing and building an oxy-fuel combustion pressurized fluidized bed.

氧燃料燃烧加压流化床中的高压，复杂的烟气成分和稀相区域中的热辐射传递是复杂的。为了进行辐射传热，基于灰气体的加权和模型（WSGG）和米氏理论进行了数值模拟。采用离散坐标法求解了鼓泡流化床和循环流化床的辐射传递方程。验证了空气燃烧下流化床的辐射传热，然后在加压氧-燃料燃烧假设下完成了模拟。结果表明，在加压的含氧燃料燃烧下，粒子辐射仍占主导地位。总压力和气体组成的变化对流化床中的辐射传热影响很小。新的加压WSGG模型描述的气体辐射和身体坐标系的RTE求解对于模拟辐射传热非常准确。所有结果均具有重要意义，可为设计和建造氧燃料燃烧加压流化床提供理论依据。