In this study, the application of computational fluid dynamics (CFD) is explored to predict the performance characteristics in a typical single-stage downhole turbine. The single-stage turbine model utilized for this study consists of a stator and a rotor. A finite-volume based CFD approach was implemented to simulate the complex flow field around the turbine. The analysis is based on transient, three-dimensional, isothermal turbulent flow in an incompressible fluid system. The inlet flow rates and angular velocity of the rotor were varied to encompass the operating regime.
Comparison with experimental data revealed excellent agreement, proving reliability of the model in predicting the performance characteristics. Motivated by the successful model validation, a parametric study (considering blade tip clearance and blade count) was also conducted to understand the effects of the design parameters on the performance of the turbine. Detailed flow visualizations and efficiency calculations were also done to provide further insight into the overall performance of the turbine. As part of the present study, significant efforts were also spent in the following areas: standardization of CFD methodology and assessment of commercial software to develop an integrated CFD-driven design process.
