Multi-Scale Simulation of Stress Wave Propagation for Accurate Geometric Representation of Materials

应力波传播的多尺度模拟，以准确表示材料的几何形状

• 批准号: 2118088
• 金额: --
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2118088
• 关键词: Multi; Scale; Simulation; Stress; Wave

This research will involve the further development of a novel code for multi-scale simulations (using different meshes in the same simulation, fine and coarse) that model the behaviour of materials, with particular attention to wave phenomena (stress waves) that occur during the rapid mechanical excitations (i.e. vibration) of materials systems and structures. The project will focus on the coupling mechanics (i.e. how a fine and coarse mesh interact with each other) during simulations, where fine meshing will be used on areas of a material where damage phenomena is expected, and therefore a coarse mesh will not accurately model the structure. However, a coarse mesh will be utilised in most places along the material during the same simulation, where the material is expected to have little deformity, whereby a coarse mesh is more than sufficient and this would significantly improve the computational time. The research will also focus on applications of NURBS (a well-known technique in the realm of research in numerical modelling, for ensuring that a simulation models a shape accurately) for modelling of complex geometries in particular, as the current finite element based simulations pose difficulties with accurate representation of a structures geometry.The impact of the research will be the development of new computational mathematical techniques for tackling many of the typical problems that are associated with multi-scale modelling, as mentioned, these problems stem from issues in the coupling mechanics and the accurate representation of a materials geometry. All engineering companies that apply finite element simulations to their work (nearly every large engineering company) wish for ways to reduce the computational time of their simulations as long as it does not sacrifice accuracy, therefore, the development of an accurate simulation technique where fine meshing (that takes a large amount of time) coupled accurately to a coarse mesh (that takes far less time) that can be applied to areas of less interest along a structure, would certainly have an impact on the industry, as long as the geometry of the actual structure can be modelled sufficiently well. Some companies will already be developing multi-scale code in-house, but the implementation of the new techniques that will be developed during this research will still have a large impact on the success of these solvers. Aims and objectives;1. Derive a novel mathematical technique for a more accurate modelling of coupling mechanics at the boundary between a fine and coarse mesh then the current industry techniques. A stress wave will then be simulated along a material and the accuracy of the computer simulation will be compared to experimental data. 2. Apply the use of NURBS to more accurately model the geometry of a structure. Due to the novelty of the multi-scale framework, a novel technique for applying NURBS will need to formulated both mathematically and computationally. A stress wave will again be modelled and compared to experimental data. This project falls within the EPSRC Materials Engineering - metals and alloys research area.This project is part-funded by Rolls-Royce and so there will be some collaboration with them and their materials department. At this stage it is not decided how involved Rolls-Royce wish to be in the research, I am hoping they can experimentally model some aerospace grade metal and I can compare my results against this.

这项研究将涉及对多尺度模拟的新代码的进一步开发（使用同一模拟中的不同网格，细和粗糙），以对材料的行为进行建模，尤其要注意在此期间发生的波浪现象（应力波）材料系统和结构的快速机械激发（即振动）。该项目将集中于模拟过程中的耦合力学（即细分和粗网格如何相互作用），在模拟中，将在预期损坏现象的材料区域上使用细分市场，因此，粗网格不会准确地建模。结构。但是，在同一模拟中，将在材料沿材料的大多数地方使用粗网格，那里预计材料的畸形很小，从而使粗网格远远足够，这将显着改善计算时间。这项研究还将重点关注NURB的应用（数值建模领域的众所周知技术，以确保模拟准确地模拟形状），以尤其是对复杂几何形状进行建模，因为当前基于有限的元素构图姿势姿势具有准确表示结构几何形状的困难。研究的影响将是开发新的计算数学技术来解决与多尺度建模相关的许多典型问题，如前所述，这些问题源于耦合中的问题力学和材料几何形状的准确表示。所有将有限元模拟的工程公司（几乎每家大型工程公司）都希望减少模拟的计算时间，只要它不牺牲准确性，就可以开发精确的模拟技术，而精细的网格融资技术（这需要大量时间）准确地耦合到一个粗网格（少于时间），可以应用于结构较少感兴趣的领域，只要几何形状的几何形状就会影响该行业实际结构可以很好地建模。一些公司将已经在内部开发多尺度代码，但是在这项研究中将开发的新技术的实施仍然会对这些求解器的成功产生很大的影响。目标和目标； 1。得出一种新型的数学技术，以更准确地建模，在细网和粗网之间的边界和当前行业技术之间的边界之间进行更精确的建模。然后将沿材料模拟应力波，并将计算机模拟的精度与实验数据进行比较。 2。应用NURBS更准确地对结构的几何形状进行建模。由于多尺度框架的新颖性，用于应用NURB的新技术需要在数学上和计算上同时表达。应力波将再次建模，并将其与实验数据进行比较。该项目属于EPSRC材料工程 - 金属和合金研究区域。该项目由Rolls-Royce资助，因此将与他们及其材料部门进行一些合作。在此阶段，尚未决定劳斯莱斯（Rolls-Royce）希望如何参与研究，我希望他们可以实验对某些航空航天级的金属进行建模，我可以将结果与此相比。