Determination of geothermal reservoirs performance by finite elements method

ABSTRACT Ph.D. Thesis DETERMINATION OF GEOTERMAL RESERVOIRS PERFORMANCE BY FINITE ELEMENTS METHOD Ibrahim CAN Atatürk University Graduate School of Natural and Applied Sciences Department of Civil Engineering Supervisor: Asst. Prof. Dr. Ahmet BUDAK In this study, an essential formulation has been derived to solve two dimensional (areal) mass and energy transport partial differential equations by finite elements method for the purpose of transient performance determination of hot water dominated geothermal reservoirs. A computer programme has been developed by using derived formulation and transient simulation of Denizli-Kızıldere geothermal reservoir, which is one of the largest geothermal fields in Turkey, has been done. The developed computer programme is a general one which is capable of simulating any of the two dimensional hot water dominated geothermal reservoir. Using Kızıldere geothermal reservoir pressure drawdown versus time between 1984 and 1998 it has been found that the reservoir thickness is 1200 m, porosity is 0.15 and permeability is 4.17xl0"10 cm2. At the Kızıldere jeotermal reservoir, six varied production scenario has been put into practice, and reservoir and production wells life has separately been determined. It has been determined that Kızıldere geothermal reservoir life is 103.3 years, 36.2 years, 24.6 years, 13.1 years, and 6.9 years for 670 t/h, 870 t/h, 1000 t/h, 1305 t/h, 1500 t/h, and 1740 t/h total geothermal fluid production, respectively. 2002, 107 pages Keyword: Geothermal energy, geothermal reservoir, finite elements method, simulation, Kızıldere geothermal field u