The numerical simulation of Fluent on bias pulverized coal(PC) jets ignition was conducted to optimize the design of 250-kW biaspulverized coal straight jets combustion simulator,which are conducive to build a pilot-scale bias PC combustion experimental facility.The results indicates that with changing of the intersection angles between bias PC jets and high temperature flue gas jets,the central axial velocities all increased sharply first at beginning of the jets,then decreased after reached the peak value.When the intersection angle was 20°,the peak value of central axial velocity was greatest,the energy loss of resultant jets was least.When the intersection angle was bigger than 20°,the continuous flame delay distance decreased slightly.The results shows that the final intersection angle should be selected at 20°,then the turbulent flow and heat transfer behavior of the jets were consistent with the actual tangential fired PC boiler,the resultant jets propagated the flame down the central axis of the furnace,and the shape of bias PC jets after ignition was unchanged.%为了优化250 kW浓淡煤粉直流射流燃烧实验装置设计的关键参数,本文利用Fluent 软件对浓淡煤粉射流的着火过程进行数值模拟研究,完善了中试规模的浓淡煤粉燃烧实验平台.结果表明,随着浓淡煤粉射流与高温烟气射流的相交角度的变化,中心轴向速度均是从射流起点开始急剧增加,达到峰值速度后开始逐渐衰减;相交角度为20°时,中心轴向速度的峰值最大,汇合流的能量损失最小;相交角度大于20°后,连续火焰延迟距离减小的幅度不明显.研究认为实际相交角度选为20°时,各股射流的湍流流动和传热行为与实际切圆锅炉相符,汇合流沿着炉膛中轴线向下传播,浓淡煤粉射流着火后形态未变化.
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