风沙运动的散体动力学模型及其动力学过程

Discrete particle dynamics model and dynamic process for blown sand sport

风是散体沙粒运动的原动力 ,使沙粒在一定的空间和地形中运动。在一定的时空尺度内 ,风沙运动具有离散系统的动力学特征。运用DEM(散体单元法 ) ,结合相关学科的研究方法 ,依照系统中风场对沙粒的作用机制 ,确立沙粒之间以及沙粒与沙床之间的本构关系 ,设立相应的边界条件 ,建立风沙粒沙床的离散系统的散体动力学模型。从单颗沙粒这一基本尺度出发 ,对风沙运动研究中重大问题纳入同一散体模型 ,并对风沙运动过程中沙粒所表现出的各种运动方式 ,视为风沙系统的动力学同一问题 ,进行整体描述。在此基础上 ,可建立相应的实验模型 ,对散体动力学模型的理论模拟结果和实验结果进行对比。验证所建模型的正确性和可行性。这一探索将为风沙运动的分析研究提供新的思路和方法 ,对于促进风沙运动理论的发展和防治沙实践 ,都有十分重要的意义。

Motive power of discrete blown sand sport can be regarded as motive blown sand, it is the sport process in certain space and topography of sand grains, within space-time of certain yardstick, and it can be regarded as a discrete system. Based on DEM (the Discrete Element Method) to combine relevant discipline relevant research approaches and knowledge, according to the function mechanism of the wind-field to sand in the system, the natural relation within sand grains and between sand grains and sandy bed were established. According to corresponding border condition, the discrete dynamics model of the discrete systems of wind-sand-sandy bed was set up. Based on the basic yardstick of single drops of sand, blown sand dynamics process of system was made a further study. To blown sand question that have great significance carry on research in studying, blown sand process various kinds of sport way sand grains demonstrate describe as blown sand and the same question of dynamics of system wholly, they were described together. Corresponding experimental model was set up, theory simulation results and experimental results of the dynamics model of prose style free from parallelism with research were compared, and exactness and feasibility of the model were proved. New trains of thought and methods for analysis and research that the blown sand moves will be offered and development of the blown sand moves studying in theory and application of actual sand protection and control will be promoted by the exploration of this subject.