The Wellbore Simulator FloWell

Abstract

This paper discusses a new wellbore simulator FloWell. FloWell is a simple wellbore simulator designed to model single phase, two phase and superheated steam flows in geothermal wells. The paper discusses both features and limitations of FloWell and the assumptions and constraints made in the design phase. To validate FloWell, data from two geothermal fields, Reykjanes and Svartsengi, in the Reykjanes peninsula in Iceland is used. Results from the validation are provided both graphically and visually. Emphasis is placed on examining empirical equations used when modeling two phase flows where existing void fraction correlations are studied in depth. A comparison is made between several void fraction correlations and a ranking order established which identifies the correlations that perfom the best in simulating the diverse characteristics found in geothermal wells. Furthermore, an attempt is made to improve parameters in the void fraction correlations so simulations with FloWell better fit measured data and the results analysed to see if there is a pattern forming between wells. FloWell can be used individually to simulate the behavior of producing geothermal wells but is also designed to be coupled to a reservoir simulator in a moderately simple way. Coupling of the wellbore simulator FloWell and the reservoir simulator TOUGH2 is described in the paper A Coupled Wellbore-Reservoir Simulator Utilizing Measured Wellhead Conditions.