Summary
The work of Mandl and Volek1 is extended analytically to include the effect on the volume of the steam zone in one layer owing to heat transfer from a second layer undergoing steam injection. The contribution of the heat transfer delays the onset of heat convection across the advancing condensation front (the critical time) and significantly increases the volume of the steam zone even where 30 or more feet separate the layers. The increase in the heat content of the steam zone (or volume) increases with increasing ratio of the sensible to latent heat of the injected steam, and is larger than the increase in the total heat content. The interpretation for this behavior is that heat transfer delays the rate of condensation of the steam vapor, this being more important at poor steam qualities. Results of the simple approach presented here have been confirmed qualitatively through numerical simulation.