海底犁式挖沟机犁体动力学数值仿真分析

有效模拟海底犁式挖沟机犁体土壤挖掘过程及分析犁体受力情况对整机结构优化及提高操控性具有重要意义.本文分析了线性Drucker-Prager塑性屈服准则的土壤弹塑性本构方程,结合一阶线性水波对海底土壤的动压力方程,建立犁体、海底土壤及海流的动力学方程,采用ABAQUS无网格粒子法进行仿真模型的数值求解.通过陆地试验结果验证基于无网格粒子法的犁体挖掘土壤仿真模型的可行性.针对海底作业情况仿真,结果表明水波对犁体牵引力产生正弦影响.同时揭示犁体作业时土壤的应力变化过程,随着土工参数值的增加,犁体牵引力呈非线性增加,其中弹性模量影响较大,不排水剪切强度及摩擦角影响近似.

Decomposition of Plant Materials in Upland and Submerged Soils Under Different Climatic Conditions

The decomposition of plant materials in soil, along with the factors affecting it, has been frequently studied, and much information has been accumulated. Most reports indicated that the decomposition of organic materials proceeded more slowly in paddy soil than in upland soil because of the insufficient 02 supply, the lower soil temperature and the weaker activity of aquatic invertebrates in the former as compared with those in