【作者】 王皓；

【导师】 梁冰；

【作者基本信息】 辽宁工程技术大学 ， 工程力学， 2007， 博士

【摘要】 作为经典流体力学、数值计算方法和计算机技术三者的有机结合体,计算流体力学异军突起,得到不断发展和壮大,成为科学研究和工程设计的有效手段。理论分析、实验研究和数值模拟三者相互渗透,不仅推动了流体力学理论的新发展,而且加强了流体力学的工程应用。磁流体推进系统以其独特优势成为21世纪一种颇有发展前途的船舶推进方式,对流体流动过程的计算机模拟和数值计算在理论指导实践方面意义深长,值得探索、开发和实践。本文从导电的液体处在电场和磁场当中受力出发,分析了电解质溶液在电磁场中的驱动能力与运动情况,阐述了电磁流动模型,设计出实验装置,获得实验数据分析,应用强大的数值分析方法将通道内的电解质溶液进行耦合场分析,得到理论、实践和模拟分析的具体结果。首先,分析电解质溶液在电磁场中驱动的机理,建立出理想条件下的体积力数学模型,推得电解质溶液在直流与交流电磁力驱动下的数学模型和运动方程,得到电场和磁场与运动的关系。其次,设计电磁驱动的WHLT-1型流动显示实验装置,设计减小观察驱动场区域的入口速度的方法及设施元件,构造流场观察布光的最佳方案与设备;设计光电检测实验装置对待测流场驱动和速度驱动时测量电解质溶液流动的速度方法,得到电解质溶液的流速与电压、电流的数据;设计应用CCD观察与拍摄流场流动图像的方法,采用图像分析与转换技术得到分析与处理流场的矢量图等数据。采用实物拍摄获得电解质溶液驱动分布图像和不同时刻的流场分布等图像内容。第三,应用格子Boltzmann数值方法分析推导了二维九点格子模型从微观到宏观的转变,得到演化方程,并对格子Boltzmann方法的初始条件、适用范围和边界条件设定进行了细致探讨,获得了修正添加体积力的分析方程,结合本问题的选择模型,编制了二维格子Boltzmann方法计算软件,获得了可视化计算结果演示,并验证了实验结果,为后期对比提供支持,发掘出该方法在本问题中的物理本质,增进对该方法的本质上的认识。第四,使用有限元法对通道内的电解质溶液进行电磁驱动分析,推得耦合的离散化分析方程,应用ANSYS分析软件建立三维数值模拟分析模型,获得电解质溶液在电场、磁场和电磁场中的运动分析结果,电磁力分析结果,耦合驱动流场速度分析结果,以及圆柱绕流分析等。最后,对本文的实验结论、两种数值分析方法结果进行比较分析和总结,并提出今后进一步研究的主要方向。更多还原

【Abstract】 A new force suddenly rises, the computational fluid dynamics, as an organic union of classic fluid mechanics,numerical computation methods and computer science,develops to become the efficient means of both science research and engineering design.The interaction among theoretical analysis,experimental research and numerical simulation promotes both the theoretic renovation and engineering applications of fluid mechanics. The magnetic fluid propelling system, with its typical superiority, has become a developing boat propelling method in 21st century. It has great direction value on both computer simulation and numerical computation of flowing course of fluids. So it is worth exploring, developing and practice.In this article, starting from the receiving force of conducting liquid in both electric field and magnetic field, we analyzed the propelling ability and motion states of electrolyte solution in electromagnetic field, expounded the model of electromagnetism flow, designed an experiment device, and got the experiment data. We also analyzed the coupled field of electrolyte solution in passageway by numerical computation methods, and got specific results of theory, practice and simulation analysis.First, we analyzed the principle of the electrolyte solution propelled in electromagnetic field, and then set up a mathematic model of volume force under an ideal condition, inferred a mathematic model and move equations of the electrolyte solution propelled by both direct and alternating current, and received the relations between electric field (magnetic field) and motion.Second, we designed a WHLT-1 experiment device of flow display propelled by electromagnetic field, set up methods and equipment components which can diminish or eliminate the entrance speed of the observation propelling field area, structured the best plan and equipments observing light in flow field, designed an optoelectronic detecting device to measure the flow speed of electrolyte solution propelled by flow field and speed individually, got the data of flow speed, voltage and electric current of electrolyte solution, designed methods of observing by CCD and taking the pictures of flow field, obtained the vectogram data by analyzing and changing Images, got pictures of the propelling distribution and the flow field distribution of electrolyte solution at different moment.Third, we analyzed and induced the change of a model of two-dimensional 9 points lattice from microcosmic to macroscopic field by the lattice Boltzmann numerical method, got evolution equations, discussed the initial conditions, applicable range and boundary conditions, got equations of amending the added volume force, programmed a software for calculating by the Boltzmann method of two-dimensional lattice, obtained the demonstration of visualable result and verified it. This provided support for later contrast. We improved reorganization of this method by exploring its physics nature.Fourth, we analyzed the electromagnetism propelling of electrolyte solution in passageway by finite element method, inferred the discretization of the coupling for equations, set up a three-dimensional numerical simulation model by ANSYS software, got the results of motion analysis, electromagnetism force analysis, flow-field speed analysis and flow around cylinder of the electrolyte solution in electric field, magnetic field and electromagnetic field respectively.Final, we summarized the experiment results and contrasted the two numerical analysis methods in this article, and brought up the future study direction.更多还原