针对燃烧器四角切圆布置的超超临界锅炉炉膛内的流动和燃烧，创建几何尺寸和边界条件完全对称的三维锅炉模型。计算结果表明，即使几何尺寸和边界条件完全对称，温度场和流场也可能是非对称的，这是造成烟气侧热偏差的可能原因之一。探讨了减小锅炉炉膛出口热偏差的方法，通过对比对称方位燃烧器连线上的速度分布，调整速度分布不对称的直线两端的燃烧器出口速度，使边界条件不对称，重新进行数值模拟，如此重复直至速度分布对称。结果表明，经过速度调整后所得的温度场和流场分布更加对称，可以达到减小炉膛出口热偏差的目的。%Aiming at the flow and combustion in a tangentially-fired ultra-supercritical boiler,a 3D model with symmetrical geometry and boundary conditions was built. The calculation results show that even if the geometry and boundary conditions are completely symmetrical,the temperature field and flow field may still be asymmetrical, which can result in thermal deviation. The method for reducing the thermal deviation of furnace exit was discussed, the velocity distribution on the line between two burners located symmetrical was compared,and asymmetrical ve-locities were adjusted repeatedly until symmetrical velocity distribution was obtained. The calculation results show that the temperature field and flow field are more symmetrical after velocity adjustment,which can reduce thermal deviation.
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