Modelo de Circulação Hidrotermal em Meios Fraturados: Aplicação para Estudo do Intercâmbio Térmico das Áreas Geotermais

In the present work we consider a simple semi-analytic model of heat transfer in fluid flow through subsurface conduits with impermeable walls as a means of investigating the temperature fields in geothermal areas. Results of numerical simulations based on finite difference methods are compared with results of generalized integral transform methods. The model is sufficiently flexible allowing determination of temperatures along the conduits in recharge and discharge zones as well as the intermediate zone of hydrothermal reservoirs. The success of the model however depends on the availability of complementary information on the structural and hydrogeological characteristics of the geothermal area. A number of tests were carried out for evaluating the effects of critical parameters such as temperature gradient, flow rate, dip angle of the fault zone and depth of the aquifer. As an example of application the model was employed for calculating the temperature field in the geothermal area of Cachoeira Dourada (GO). The model is also potentially useful in investigating paleothermal conditions of hydrothermal ore deposits.