Estimation of Slip Ratios for Pressure Drop Calculations in Geothermal Wells

• Main Author: Þóra Hlín Þórisdóttir 1986-
• Other Authors: Háskóli Íslands
• Format: Thesis
• Language: English
• Published: 2013
• Subjects: Vélaverkfræði; Þrýstiföll; Líkön; Borholur; Borholumælingar; Reykjavík
• Online Access: http://hdl.handle.net/1946/13937

The goal of the projects is to estimate a correlation of slip ratio between gas-and liquid velocity in a two phase flow in a geothermal well. Initially, a model which calculates pressure drop from the bottom to the wellhead in a geothermal well was developed in Matlab. Then measured data of pressure and depth which was provided by Reykjavík Energy and HS Energy was used to evaluate the models accuracy and use to make a correlation of the slip ratio. In addition 6 previously known void fraction correlations were tested to see how they fitted according to the measured data. The result was that due to insufficient accuracy of the measurements, a new model could not be developed. However the thesis concludes that a model that assumes no difference in velocity between the gas and liquid phases is the best for this application until better measured data can be obtained. Based on these conclusions it is recommended that more accuracy should be introduced in the measurement process, such as gathering all the data at the same time. Better equipment and techniques could also contribute to the development of better correlations which could be used make better prediction models for pressure drop.