Simulation Model of The Collision Event of Submarine Mudflows Exerting A Horizontal Pipeline

Abstract

The collision between submarine slide and sub-sea pipelines was simulated through laboratory experiment in order to investigate drag force exerted by mudflow on pipe surface. Mud model used was slurry of kaolin clay-water mixtures. Gravity flow concepts of fluid mechanics principles were implemented by lock-exchange system. It was developed through the laboratory equipment of rectangular channel to generate the mudflow in water ambient. A crosswise pipe stem positioned at certain run-out distance. It was collided by mudflow. The collision attributes of velocity (u), Reynolds number (Re), maximum drag force exerted by mudflow (Fdmax) and drag force coefficient (Cd) were observed based on ratio between water depth (at pipe position) and pipe diameter, abbreviated as H/d. Overall, higher H/d ratio generated higher values of collision attributes. H/d ratio variations had similar constant of Power-law model expression in Re-Cd relationship. It proved that H/d ratio had not effect to Cd very much. The current experiment also generated a high similarity trend line of Re-Cd relationship graph with the previous study. It indicated that the content of clay material (i.e. kaolin) play a major role in mudflow movement and collision, whereas granular materials (used in previous study) provide an extra density.