Transient effects in geothermal convective systems.
This work is a detailed analysis of the transient behaviour of geothermal
convective systems. The flow in these systems is found to be fluctuating or regular
oscillatory in a simplified two-dimensional model and these unsteady effects persist
when the model is refined to include the concepts of temperature dependent viscosity
and fluid withdrawal and recharge. The analysis is extended into three dimensions
to verify this behaviour. The supplementary exploration of added salinity gradients
indicates transient effects of a different kind in this case. The examination of
the porous insulator problem confirms the results of previous authors and verifies
the viability of the numerical methods that are used throughout the investigation.