Pressure drop, gas hold-up and heat transfer during single and two-phase flow through porous media

Abstract

Pressure drop, bubble size, gas hold-up and convective heat transfer have been studied both experimentally and theoretically at constant wall heat flux for single and two-phase flow through unconsolidated porous media. Single-phase pressure drop and heat transfer coefficients have been measured over a wide range of particle size, heat flux and liquid flow rate. The conservation equations and the Kozeny-Carman equation are used to describe single-phase flow pressure drop and convective heat transfer through the porous media. The measured pressure drops have been used to evaluate the validity of the predictive expressions available in the literature. Mathematical models are developed for the prediction of temperature profiles and single-phase heat transfer coefficients, which predict the experimental data with good accuracy. A large number of new experimental data are presented on two-phase pressure drop, bubble size, gas hold-up and heat transfer coefficients for co-current upward gas/liquid flow through beds of different particle sizes under constant wall heat flux. The experimental data suggest the existence of two distinct regimes, i.e. homogeneous and heterogeneous flow. The experimental data on two-phase pressure drop and gas hold-up have also been compared with the prediction of published correlations. Finally, mathematical models are presented for the prediction of pressure drop, bubble size, gas hold-up and heat transfer which predict the experimental data with good accuracy.