Flow channeling and condensation in packed beds
This work presents an investigation of two important problems in flow and heat transfer inside porous media: the flow-channeling effect of a high-porosity region near the wall of a packed bed, and the effect of the presence of a constant-porosity or variable-porosity medium on the heat transfer due to condensation of a working fluid on a cold boundary. Flow channeling and condensation have a significant impact on heat and mass transfer in many engineering applications. A closed-form analytical solution for the velocity is obtained, first assuming a constant-porosity medium, and then using an exponential porosity distribution typical of packed beds. The effect of wall channeling on heat transfer due to laminar film condensation in porous media having either constant porosity or variable porosity is explored theoretically, and the results are compared with previous work. No previous experimental data on the local heat transfer due to condensation inside a porous medium are available for comparison. The experimental results for heat transfer obtained here are compared with predictions. Results are presented graphically, and, where appropriate, in expressions showing the dependence on the most important flow parameters.
- Research Organization:
- California Univ., Berkeley (USA)
- OSTI ID:
- 6904985
- Country of Publication:
- United States
- Language:
- English
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