CIESC Journal

• 化工学报 • 上一篇    下一篇

应用傅立叶解析的参数估值法——固定床流体与颗粒间给热系数的测定

沈静珠,影井清一郎,若尾法昭   

  1. 清华大学化学与化学工程系 ,日本横滨国立大学工学部 ,日本横滨国立大学工学部
  • 出版日期:1981-06-25 发布日期:1981-06-25

Parameter Estimation by Fourier Analysis——Determination of Gas-Particle Heat Transfer Coefficient in Packed Bed

Shen Jingzhu S. Kagei and N. Wakao Department of Chemistry and Faculty of Engineeting, Chemical Engineering, Yokohama National University, Qinghua University, Japan. China.   

  • Online:1981-06-25 Published:1981-06-25

摘要: 采用任意波形的输入温度信号对固定床进行温度应答实验,根据实验结果,对固定床的Disperison-Concentric模型进行傅立叶解析,在Re数0.5到229的范围内,拟合确定固定床中流体与颗粒的给热系数。 结果表明:在层流区,流体与颗粒间传热的Nu数并不随Re数的下降而减小。

Abstract: A stimulus-response technique is used to determine gas-particle heat transfer coefficient in packed bed. The input signal is a one-shot temperature impulse of arbitrary shape and at a distance downstream from the input point the temperature response is measured. The mathematical model adopted for the packed bed is one-dimensional heterogeneous Dispersion-Concentric model. Laplace transform method is used in the solution of the partial differential equations of the model. As the resulting transfer function is too complicated, a Fourier analysis method is applied. The input and response signals are both expanded in Fourier series form. The Fourier coefficients of the response signal can be predicted directly from those of the input signal and the transfer function and thus the calculated response signal function is obtained, which can then be fitted with the measured one to carry out the parameter estimation. In the procedure of curve fitting the mean square deviation between calculated and measured response functions in the whole time domain is minimized. It is found that the result of this work can be put into an expression assuming the same form of a known correlation of mass transfer Nu=2+l.lPr1/3Re0.6 in which the Nusselt number Nu contains the gas-particle heat transfer coefficient determined. The result also shows that in the laminar flow regime the Nusselt number of gas-particle heat transfer does not decrease appreciably with the decrease in Reynolds number. The exprimental equipment is also described in the paper.