中文摘要：

海底犁式挖沟机犁体工作面的结构直接影响挖掘效率及牵引力大小,对犁体工作面进行数学建模分析及挖掘机理研究具有重要的理论指导和工程实践价值。利用空间平面及水平直元线法建立犁体主切削面和翻抛曲面方程,根据翻抛土壤能量最小方向得到土迹线方程,基于犁体工作面土壤运动机理建立土壤裂解和翻抛的动力学方程,据此确定了牵引力的理论计算方法。数值仿真计算表明,翻抛曲面曲率影响土壤翻抛的法向力及切向力,牵引速度的变化对土壤翻抛的切向力影响较大;影响主切削面受力的主要因素包括土壤粘聚力和内摩擦角,且随着粘聚力与内摩擦角增加,后者对主切削面受力影响较大。海底犁式挖沟机试验样机的陆地试验结果与理论计算结果基本吻合,例如当沟深为0.8 m时,实测牵引力与理论值的相对误差为3%,试验结果验证了所建立的犁体牵引力的理论计算方法的可行性。该研究可以有效预测海底犁式挖沟机工程样机的牵引力,进而为工程样机的设计及海试等提供理论和技术参考。

英文摘要：

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.