典型L形型材的精细建模方法研究
发布时间：2019-05-18 05:22
【摘要】：典型L形型材广泛应用于薄壁梁结构及框架结构中,在L形型材的有限元分析中通常采用的单根L形截面梁建模方法与实体结构存在一定的误差,提高L形型材的建模精度和计算效率对整体结构振动特性研究有重要意义。本文首先用两种不同的实体单元、壳单元和梁单元对典型L形型材进行了建模分析,发现忽略倒角及采用单一的壳单元和梁单元建模的模型质量不好,这是由于单一的壳单元和梁单元模型不能准确地模拟倒角的形状。在倒角处加上另一个垂直于“桥”的壳单元支撑“桥”,建立了以壳单元为基础的等效壳单元模型。针对单位长度截面微段,通过使自重下等效模型截面与真实截面的变形相同,根据结构力学中力法的相关原理对等效模型的相关参数进行了详细的推导,确定了仿真建模所需的壳单元厚度的参数。采用推导得到的壳单元参数建立了三维的等效壳单元模型,通过频率分析得到了等效壳单元模型前51阶频率,并与细节体单元模型的频率误差进行了对比分析,前10阶模态频率误差控制在3%以内。然后研究了渐进结构拓扑优化理论在几种典型平面应力梁结构应力分析中的应用,经过反复的有限元分析和单元删除循环,直到达到稳态,得到满应力结构。为进一步通过拓扑优化理论分析L形型材提供了参考依据。最后基于对L形型材的螺栓联接结构相关参数分析对L形型材的螺栓联接建模方法进行了研究。
[Abstract]:Typical L-shaped profiles are widely used in thin-wall beam structures and frame structures. There are some errors between the single L-section beam modeling method and the solid structure commonly used in the finite element analysis of L-shaped profiles. It is of great significance to improve the modeling accuracy and calculation efficiency of L-shaped profiles for the study of vibration characteristics of the whole structure. In this paper, two different solid elements, shell element and beam element, are used to model and analyze the typical L-shaped profile, and it is found that the quality of the model which ignores chamfer and adopts a single shell element and beam element is not good. This is due to the fact that the single shell element and beam element model can not accurately simulate the shape of chamfer. An equivalent shell element model based on shell element is established by adding another shell element perpendicular to the "bridge" to support the "bridge" at the chamfer. Aiming at the microsection of unit length section, the related parameters of the equivalent model are deduced in detail according to the related principle of force method in structural mechanics by making the deformation of the equivalent model section and the real section the same under the self-weight. The parameters of shell element thickness needed for simulation modeling are determined. A three-dimensional equivalent shell element model is established by using the derived shell element parameters, and the frequency of the first 51 order of the equivalent shell element model is obtained by frequency analysis, and the frequency error is compared with that of the detailed element model. The first 10 order modal frequency error is controlled within 3%. Then the application of progressive structure topology optimization theory in the stress analysis of several typical plane stress beams is studied. after repeated finite element analysis and element deletion cycle, the full stress structure is obtained until the steady state is reached. It provides a reference for further analysis of L-shaped profiles through topology optimization theory. Finally, based on the analysis of the related parameters of bolt connection structure of L-shaped profile, the modeling method of bolt connection of L-shaped profile is studied.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB12
[Abstract]:Typical L-shaped profiles are widely used in thin-wall beam structures and frame structures. There are some errors between the single L-section beam modeling method and the solid structure commonly used in the finite element analysis of L-shaped profiles. It is of great significance to improve the modeling accuracy and calculation efficiency of L-shaped profiles for the study of vibration characteristics of the whole structure. In this paper, two different solid elements, shell element and beam element, are used to model and analyze the typical L-shaped profile, and it is found that the quality of the model which ignores chamfer and adopts a single shell element and beam element is not good. This is due to the fact that the single shell element and beam element model can not accurately simulate the shape of chamfer. An equivalent shell element model based on shell element is established by adding another shell element perpendicular to the "bridge" to support the "bridge" at the chamfer. Aiming at the microsection of unit length section, the related parameters of the equivalent model are deduced in detail according to the related principle of force method in structural mechanics by making the deformation of the equivalent model section and the real section the same under the self-weight. The parameters of shell element thickness needed for simulation modeling are determined. A three-dimensional equivalent shell element model is established by using the derived shell element parameters, and the frequency of the first 51 order of the equivalent shell element model is obtained by frequency analysis, and the frequency error is compared with that of the detailed element model. The first 10 order modal frequency error is controlled within 3%. Then the application of progressive structure topology optimization theory in the stress analysis of several typical plane stress beams is studied. after repeated finite element analysis and element deletion cycle, the full stress structure is obtained until the steady state is reached. It provides a reference for further analysis of L-shaped profiles through topology optimization theory. Finally, based on the analysis of the related parameters of bolt connection structure of L-shaped profile, the modeling method of bolt connection of L-shaped profile is studied.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB12
【相似文献】
相关期刊论文 前10条
1 皮亚南,刘燕霞,汪先明,朱宇姝;胀塞式过盈普通螺栓联接[J];南昌大学学报(工科版);2003年01期
2 赵福亮;提高螺栓联接强度的施工安装措施[J];机械工程与自动化;2004年03期
3 岳桂杰;保承军;同长虹;;螺栓联接设计中应注意的问题[J];装备制造技术;2009年12期
4 刘琳;米雪莲;;浅议如何提高螺栓联接强度[J];科技创业家;2013年14期
5 ，
本文编号：2479715
本文链接：https://www.wllwen.com/guanlilunwen/gongchengguanli/2479715.html
