Modelling structured geothermal systems: Application of dimensional methods

Dimensional methods are used for interpretation of field data from the geothermal systems in Wairakei (New Zealand), The Geysers (California), and Larderello (Italy). Nondimensionalization is performed at both microscopic and macroscopic levels and the set of key nondimensional parameters is determined. It is shown that steep temperature gradients found immediately below vapour-dominated regions of Wairakei and The Geysers indicate transition to a single-phase flow regime, while the flow beneath a vapour-dominated region of Larderello remains two-phase. The geothermal processes that lead to the formation of zones with steep temperature gradients are identified.