# Blog

### How to use MeshX to convert the mesh file from Gmsh to XDMF file in FEniCS

In FEniCS we have an option of importing the mesh geometry in .xdmf format. This makes our job much more easier and simpler. As it allows us to use different packages (Gmsh, Ansys, Abaqus etc) for complex geometry modeling and meshing. Check this postÂ  to know how to use Nastran file (.bdf) from Ansys to […]

### Variational Calculus: Deriving the strong and weak form

There are many ways in which we can obtain the weak form and the strong form. We focus on the Variational Principles to derive them because FEniCS works on the variational form

### Built-in meshes in FEniCS

In FEniCS, we can either work with the inbuilt meshes or we can also import the mesh file generated in another pre-processing tool as a xdmf format. In order to create inbuilt meshes, firstly, dolfin module is imported as: Matplotlib library is used to display the mesh plots. The different types of inbuilt meshes in […]

### A great advice that I found of the internet

Just keeping it here for future reference References http://www.cs.uni.edu/~wallingf/blog/archives/monthly/2017-08.html https://metarationality.com/rationalism-critiques https://twitter.com/sarahdoingthing/status/877018612447313920?s=20

### Boundary conditions in FEniCS

Boundary conditions (B.C.) are constraints necessary for the solution of a boundary value problem. A boundary value problem is a differential equation (or system of differential equations) to be solved in a domain on whose boundary a set of conditions is known. Boundary value problems are extremely important as they model a vast amount of […]

### A primer on shell structures

Through this post, I attempt to provide a starter pack for shell structures. This includes trying to understand their structural behaviour, a very brief overview of shell-kinematics and the basic methodology for shell analysis through FEM. The theory and implementation follows the widely popular Kirchhoff-Love theory described for thin shells (thickness/length < 20)

### Calculus with Sympy

Sympy is a python package through which we can perform calculus operations in mathematics like differentiation, integration, limits, infinite series, and so on. It is a python library used mainly for symbolic mathematics. The installation of this library is simple by using the following command: pip install sympy In order to write any symbolic expressions, […]

### Effects of volume fraction and filter radius

This blog post explains the significance of the volume fraction and filter radius in the Topology optimization (TO). Volume fraction (volfrac) Volume fraction is the fraction of the original volume that the geometry of the optimized structure will have. Since, weight reduction is the major goal and density of the material remains constant therefore volume […]

### 3D printing

3D printing as the name suggest is a method of creating a three dimensional object layer by layer from a CAD model. 3D printing is an additive process where materials are added to build the desired geometry, as opposite to machining (subtractive manufacturing) process in which material is cut off or removed from larger block […]

### Static vs Dynamic analysis

When we do our undergraduate studies, we mainly focus on static analysis. We only study the behavior of structures under static loading. But in real-life scenarios, the structure will also experience dynamic loading. So, it is essential for us to study the behavior of structures under dynamic loading. During our postgraduation, we come across the […]