Frontal Regime of Heat and Mass Transfer in a Geothermal Bed

Abstract

Based on an earlier proposed mathematical model, the conditions for the existence of a frontal regime of steam extraction from a high-temperature bed have been derived. It is shown that unlike the familiar one-dimensional case, in the radial-symmetrical model considered the radius of the region occupied by steam tends to a limiting value, that is, the front of boiling that separates the regions of water and steam practically comes to a stop after a time. A formula has been derived pointing clearly to the dependence of the indicated limiting value of the front radius on the water and steam parameters as well as on the characteristics of the geothermal bed. It is shown that for the steam to occupy a considerable region around the well when the bed is in service, it is necessary that the initial state of water be close to that of steam generation. Otherwise the front of boiling in the considered regime of heat and mass transfer extends from the well only a little.