Theoretical Prediction of the Mass Flow Rates in the Bubble Pump

Abstract

The bubble pump is an essential part of diffusion absorption cooling systems where heating, pumping of the binary solution, and the separation occur. The existing theoretical models of the bubble pump were initially developed for air lift pumps where neither heating nor separation occurs. Thus, the experimental results for a bubble pump did not correlate well with the theoretical models. Empirical values were suggested in some of the models; however, their values varied from one system to another and could not be predicted analytically. In this work a modified model based on mass, energy, momentum, and heat balances is presented with the utilization of the drift flux model with laminar flow assumption. In addition, for the first time the applied heat is expressed in the model. The suggested model fits better with the experimental results than the previous models.

Keywords

• : diffusion absorption cooling systems,bubble pump

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