GEOTHERMAL SUPERMODELS PROJECT: AN UPDATE ON FLOW SIMULATOR DEVELOPMENT

Abstract

The “Geothermal Supermodels” project is a four-year New Zealand-based research programme, a major part of which is the development of a new open-source, parallelized geothermal reservoir flow simulator, called “Waiwera”. This paper describes recent progress on Waiwera.
Features recently added include simulation of non-condensible gases, a flexible framework for modelling source and sink terms, support for radial and two-dimensional models and capillary pressure functions. Numerical performance has been improved via non-dimensionalising the primary thermodynamic variables, and better algorithms for polynomial evaluation. Thermodynamic behaviour has also been improved by implementing more sophisticated algorithms for phase transitions and for non-condensible gas energy of solution. Work has also been done to increase the efficiency of linear equation assembly and also solution, via improved pre-conditioning techniques. We demonstrate the performance of Waiwera via results from a range of benchmark tests.