Numerical Analysis of Torque on Bit on Torsional Vibrations in Horizontal Well Drilling

Abstract This paper investigates the impact of varying Torque on Bit (TOB) on torsional vibrations and rotational dynamics in horizontal drilling operations. Using a numerical simulation of a small-scale horizontal drill string, the study systematically examines the effects of TOB on bottom rotation speed (RPM)dynamics. Stick-slip behavior is observed, and a severity index is introduced as a quantitative measure of vibration intensity. The results reveal that higher TOB values amplify the severity index, indicating more pronounced torsional vibrations and rotational instability. The drill string exhibits dynamic adaptation to changing conditions, with noticeable fluctuations in RPM. These findings highlight the importance of monitoring and optimizing TOB to mitigate torsional vibrations, ensuring enhanced operational stability and efficiency in horizontal drilling.