SIMGWEL: EDC's New Geothermal Wellbore Modelling Software

Abstract

Simgwel is a new geothermal wellbore simulator intended as a tool for making resource management decisions and as well as a user-friendly alternative to existing DOS-based simulators. It is intended to model fluid flow in a geothermal well by solving steady-state conservation equations for liquid, vapor, and two-phase water with carbon dioxide gas present in both phases for testing against measured data from production or injection. Simgwel may be used to perform top-down and bottom-up simulations for vertical and deviated production and injection wells by defining the wellhead and/or feed parameters and well-geometry specifications. Its core is based on the research tool GWELL, rewritten in Fortran95 and improved to better handle effective viscosity at feeds, enable a graphical user interface, deliver output curve predictions using discharge test simulations and feed parameters and include various two-phase correlations as options for the user. Preliminary evaluation of the performance of the software using the Orkiszewski correlation was done using several discharge test cases.