Study on Transmission Characteristics of Mud Pulse Signals in Ground Manifold

Detecting and processing mud pulse signals in measurement while drilling (MWD) systems is a well-known challenge. Currently, most research is focused on the propagation characteristics of mud pulse signals along the wellbore, with comparatively little attention paid to discussing the effects of the ground manifold on mud pulse signals. This paragraph examines the effects of the ground manifold on mud pulse signals during the drilling operation. Furthermore, based on the results obtained, the research provides recommendations for enhancing the quality of the mud pulse signals. Firstly, based on the fundamental control equations of drilling fluid flow, a comprehensive mud channel model that utilizes the transfer matrix analysis method is established. Secondly, by analyzing the transmission characteristics of mud pulse signals in the ground manifold, we can optimize the mud pulse signal frequency and pressure sensor position to obtain a higher mud pulse signal amplitude. Finally, the effects of ground factors, such as the installation position of the pressure sensors and the diameter and length of the high-pressure hose, are simulated and analyzed. The results indicate that the amplitude of the mud pulse signals is negligibly affected by the position of the pressure sensor and hose parameters when mud pulse signals frequencies are below 5Hz. However, when the signal frequency exceeds 5 Hz, changes in sensor position and hose parameters have a significant influence on the signal amplitude. The results provide a theoretical foundation for selecting an appropriate frequency for the mud pulse signals in MWD systems and offer valuable insights for optimizing the installation position of pressure sensors and the parameters of the hose.