使用自由形变形,对不匹配的同位体外进行自动化形状和厚度优化.
Han Zhao1, David Kamensky1, John T Hwang1
1Department of Mechanical and Aerospace Engineering, University of California San Diego, 9500 Gilman Drive, Mail Code 0411, La Jolla, CA 92093 USA.
概括
本研究介绍了一种统一的方法,用于优化外结构,使用同位几何分析 (IGA) 和自由形变形 (FFD). 这种方法确保了多个补丁的连续性,使飞机机翼等复杂设计的形状和厚度能够有效地优化.
科学领域:
- 计算力学是计算力学.
- 结构优化 结构优化
- 计算机辅助设计 (CAD)
背景情况:
- 同地形分析 (IGA) 集成了CAD和使用NURBS的分析,简化了结构优化.
- 用多个不匹配的NURBS补丁优化现实世界的CAD几何形状,带来了重大挑战.
- 现有的方法在复杂的多补丁外结构中努力保持连续性和高效的优化.
研究的目的:
- 开发一种统一的配方,以优化具有多个单独参数化的补丁的外结构的形状和厚度.
- 在优化过程中,在补丁交叉点确保设计变量的连续性.
- 利用自由形变形 (FFD) 实现设计和分析模型的无整合.
主要方法:
- 使用自由形变形 (FFD) 来参数化外结构并保持连续性.
- 采用异几何基尔霍夫 - 爱理论用于外建模和基于惩罚的方法用于合补丁.
- 实施拉格朗奇提取来连接控制点,并利用FEniCS进行自动化分析衍生计算.
- 使用共享的提取矩阵和现有的有限元组装程序进行异地质分析 (IGA).
主要成果:
- 成功开发了一种统一的框架,用于优化多补丁外结构的形状和厚度.
- 在整个优化过程中,在补丁交叉点上的设计变量的连续性得到了保留.
- 该方法通过FEniCS的自动化分析衍生计算证明了基于梯度的高效优化.
- 在基准问题上的验证证实了对复杂的外布局,包括飞机机翼的适用性.
结论:
- 拟议的统一配方有效地解决了优化复杂,多补丁外结构的挑战.
- FFD,IGA和FEniCS的整合为结构优化提供了一个高效和强大的方法.
- 这种方法对于优化航空航天和其他工程领域的复杂设计具有重大潜力.
相关概念视频
Unsymmetric Loading of Thin-Walled Members: Problem Solving
90
The shear center of a channel section with uniform thickness, height, and width, is determined by computing the shear force in the member and calculating the moments of inertia of the sections.
To compute the shear forces, find the shear flow at a specific distance from the endpoint using the vertical shear and the moment of inertia values. The total shear force on the flange is calculated by integrating the shear flow from one end of the flange to the other.
Next, calculate the moments of...
To compute the shear forces, find the shear flow at a specific distance from the endpoint using the vertical shear and the moment of inertia values. The total shear force on the flange is calculated by integrating the shear flow from one end of the flange to the other.
Next, calculate the moments of...
90
Unsymmetric Loading of Thin-Walled Members
98
Thin-walled members with non-symmetrical cross-sections are vital to engineering structures, offering material efficiency and structural integrity. However, unsymmetrical loading on these members leads to complex stress distributions, resulting in simultaneous bending and twisting can cause deformation or structural failure. The interaction between bending and twisting requires detailed analysis to ensure structural resilience.
The concept of the shear center is crucial in countering the...
The concept of the shear center is crucial in countering the...
98
Plastic Deformations of Members with a Single Plane of Symmetry
86
When a structural member undergoes plastic deformation due to bending, it is crucial to understand the position of the neutral axis and the stress distribution. This member, characterized by a single plane of symmetry, exhibits a uniform stress distribution, with negative stress above the neutral axis and positive stress below. Notably, the neutral axis does not align with the centroid of the cross-section. This misalignment is typical in cases where the cross-section is not rectangular or...
86
Deformations in a Symmetric Member in Bending
161
When analyzing the deformation of a symmetric prismatic member subjected to bending by equal and opposite couples, it becomes clear that as the member bends, the originally straight lines on its wider faces curve into circular arcs, with a constant radius centered at a point known as Point C. This phenomenon helps to understand the stress and strain distribution within the member more clearly.
When the member is segmented into tiny cubic elements, it is observed that the primary stress...
When the member is segmented into tiny cubic elements, it is observed that the primary stress...
161
Deformation of Member under Multiple Loadings
156
When a rod is made of different materials or has various cross-sections, it must be divided into parts that meet the necessary conditions for determining the deformation. These parts are each characterized by their internal force, cross-sectional area, length, and modulus of elasticity. These parameters are then used to compute the deformation of the entire rod.
In the case of a member with a variable cross-section, the strain is not constant but depends on the position. The deformation of an...
In the case of a member with a variable cross-section, the strain is not constant but depends on the position. The deformation of an...
156
Plastic Deformation in Circular Shafts
178
When materials are subjected to forces that surpass their yield strength, they undergo a process known as plastic deformation. This results in a permanent alteration or strain in their structure. This concept can be specifically applied to circular shafts, where the deformation leads to a change in its shape. The precise evaluation of this plastic deformation requires understanding the stress distribution within the circular shaft, which is achieved by calculating the maximum shearing stress in...
178


