Dynamic Control Simulation Research on Multibranch Horizontal Well Gas Extraction System

High Resolution Image Download MS PowerPoint Slide This study uses COMSOL and Ventsim software to establish a multibranch horizontal well extraction system model that considers coal body deformation and gas seepage. It investigates the effects of valve opening variations on the negative pressure ratio and system extraction efficiency. The results indicate that when establishing a dynamic control mechanism, the pumping weights of each branch should be considered. When the drilling hole with the highest extraction efficiency is slowly closed, the negative pressure of other drilling holes will significantly decrease in a “double peak” pattern. When the non main extraction source is slowly closed, the increase in negative pressure of the drilling hole is inversely proportional to the extraction capacity; The flow increments of the three sets of dual valve joint control are 1 m 3 /s, 1.2 m 3 /s, and 1.8 m 3 /s, respectively. The highest extraction efficiency is achieved when the valve opening is 45%, 42%, and 55%.