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International Conference on Innovative Applied Energy    

E-Proceedings ISBN: 978-1-912532-05-6

St Cross College, University of Oxford, United Kingdom



CFD modelling and analysis of Two-Phase Geothermal Energy Turbine in Project Combi-Gen



Rane Sham, He Li and Ma Haiteng

Dept of Engineering Science, Southwell Laboratory, University of Oxford, United Kingdom


Paper Abstract

The Combi-Gen consortium has been established together with the Department of Engineering Science at University of Oxford to design and develop geothermally sourced combined power and freshwater generation technology. A key element of this technology is the two-phase turbine that generates the mechanical energy by means of a total flow system.

In this paper, we describe the preliminary modelling of two-phase flow using Computational Fluid Dynamics and analyse the flow regimes inside a test turbine. An Eulerian-Eulerian multiphase model has been used in the numerical solver ANSYS CFX and two-phase heat, mass and momentum transfer has been modelled using the Thermal Phase-Change model. Phase change validation study has been conducted on published experimental data on a converging-diverging nozzle flow at various operating conditions. Satisfactory results of flash boiling of liquid water to vapor were achieved by the model and quantitative data was validated with literature. The model was then extended to test turbine problem. Turbine efficiency and performance, water liquid and vapor distribution and flash evaporation boundaries were predicted by the analysis. The CFD model so established will be used further to design and optimize the two-phase turbine.

Paper Keywords
Geothermal Energy, Two-Phase Turbine, Total Flow System, Computational Fluid Dynamics, Eulerian-Eulerian Multiphase.
Corresponding author Biography

Dr Sham Rane is a Post doctoral research associate at Department of Engineering Science, Uinversity of Oxford. He specializes in the computational modelling of rotating machinery such as twin screw positive displacement machines, dynamic compressors and turbines and currently works on the design and development of two-phase flow geothermal turbines at Osney laboratory. He has carried out his PhD research at City, University of London, Centre for Compressor Technology on deforming grid generation for CFD analysis of twin screw compressors and expanders in 2015. He investigated non-classical rotor designs like variable lead and variable profile using customized computational grid generation techniques. From 2015 to 2017, as a Research Fellow at City, University of London he has been working on analysis of multiphase flows in twin screw compressors such as water spray and oil injected designs. He has also been working on extension of the CFD modelling to oil injected and ORC application rotary vane compressors and expanders. In the past Dr Rane has worked as a manufacturing engineer at Forbes Marshall India Pvt. Ltd. and computational fluid dynamics department of ANSYS FLUENT India Ltd. as an application engineer for FLUENT and CFX codes. At ANSYS, he has worked on customized UDF development, Multiphysics code coupling between Fluids and Electromagnetic solvers and development of deforming grids in positive displacement machines

The International Conference on Innovative Applied Energy (IAPE’18)