循环流化床锅炉外置床传热系数的测定和关联

Measurment and empirical correlation of heat transfer coefficient in external heat exchanger of a CFB boiler

外置床传热系数是设计大型循环流化床(CFB)锅炉受热面的关键参数。为了测定CFB锅炉外置床的传热系数,在1台热功率4MW的CFB试验台上,对外置床的传热系数进行了试验和测定,研究了外置床床温、流化速度对传热特性的影响规律。通过对试验数据的回归,得到了外置床传热系数的关联式,其计算和试验误差的绝对值小于14%,表明该关联式准确度较高,可用于CFB锅炉外置床的设计计算。

The heat transfer coefficient of external heat exchanger is key parameters for designing large-capacity circulating fluidized bed （CFB）boiler. In order to measure heat transfer coefficient in external heat exchanger of the CFB boiler, the measurement of heat transfer coefficient in the external heat exchanger was performed on a hot test facility with heating power of 4 MW. The effect of bed temperature and fluidized velocity on heat transfer characteristics was investigated. Through regression analysis on the test data,the correlation formula of heat transfer coefficient in external heat exchanger was obtained. The error between the heat transfer coefficient^s calculated value and measured value was less than 14% ,indicating the correlation equation has high calcula- tion accuracy and can be applied in design calculation for CFB boilers.