Optimization of Drilling Parameter to Minimize Torsional Vibrations in Geothermal Wells

Abstract

Geothermal drilling poses significant challenges due to high temperatures, harder rock formations, and complex geological conditions, which intensify torsional vibrations in the drill string. These vibrations adversely impact drilling efficiency, increase operating costs, and reduce equipment lifespan. This study employed numerical simulations to optimize drilling parameters, specifically focusing on mitigating torsional vibrations in geothermal wells. Key parameters such as weight on bit (WOB) were systematically varied to analyze their influence on vibration behavior. The objectives were to identify the factors most critical to torsional vibration control, develop optimization strategies, and provide best practices for geothermal drilling. A comparative analysis between geothermal and conventional wells highlighted the challenging conditions in geothermal environments, which lead to prolonged sticking phases and more severe torsional oscillations. Analysis was done to evaluate the effectiveness of different WOB values in reducing stick-slip tendencies, with findings showing that lowering WOB minimized sticking phases and improved synchronization with the top drive rotation speed. The results demonstrate that torsional vibrations are inherently more pronounced in geothermal wells due to their geological and thermal properties.