Abstract: As the working surface of the plow body of a submarine plowing trencher directly determines its trenching efficiency and the towing force, mathematical modeling and analysis of the plow working surface and the trenching mechanism have important theoretical significance and practical value. The mathematical equations for the main cutting surface and soil turning-throwing curved surface are established by using plane space method and horizontal contour line design method respectively. The soil flow equation is obtained according to the minimum energy direction of the soil turning-throwing path. The soil cutting and turning-throwing kinetic equation is built based on the soil dynamics mechanism of the plow working surface. Numerical simulation results show that the curvature of the turning-throwing surface influences both the normal force and tangential force, also the towing speed has much influence on the latter one. The force on the main cutting surface is primarily determined by the soil cohesion and internal friction angle. The impact of internal friction angle is found to be more than that of cohesion as both parameters are increased proportionately. The measured towing force for a 0.8 m deep trench is 321.4 kN while the simulated value is 312 kN, which implies that the measured value deviated from the simulated by 3%. Therefore results of the land experimental test of the prototype trencher agrees very closely with that of numerical simulation. It is therefore concluded that this modeling technique can effectively predict the towing force of the plow body of submarine plowing trencher, and provide theoretical and technical references for its further design and sea trial.

Key words: Dynamics simulation, Modeling plow working surface, Soil cutting, Submarine plowing trencher