干熄炉焦炭床层局部和平均换热系数

根据干熄炉内焦炭床层换热的特点,建立了固定床干熄炉传热模拟实验装置,针对焦炭粒度、冷却气体流量等关键参数进行了实验研究. 为有效处理实验数据,重新定义、推导了平均换热系数的计算公式,得到了干熄炉冷却段平均换热系数及其相关准则数关系,并利用导热反问题原理得到了焦炭床层的局部换热系数. 研究结果表明,局部换热系数和平均换热系数的变化规律相似,冷却气体流量增加有利于提高换热系数;换热系数对焦炭粒度较敏感,焦炭粒度变小时,换热系数增加.

Local and average heat transfer coefficients of coke bed in a coke dry quenching chamber

According to the features of coke bed heat transfer in a coke dry quenching(CDQ)chamber,an experimental setup of CDQ chamber heat transfer was established to test the primary parameters such as coke size and cooling gas flow.In order to deal with experimental data effectively,the average heat transfer coefficient was redefined and its dimensionless equation was deduced.The local heat transfer coefficient of coke bed was numerically analyzed based on the inverse heat conduction problem in the single coke.The experimental data show that the change law of average heat transfer coefficient is similar to that of local heat transfer coefficient.Both of them increase with increasing fluid flux and are sensitive to coke size,and the smaller the coke size,the larger the heat transfer coefficients.