Older articles (8/27)

1. FEA with Calculix (3)

   This is the third installment of a series of articles about how to analyze sandwich structures with FEA.

   It might be a good idea to read part 1 and part 2 first.

   In this part we will look at a simplified simulation of a three-point bending test of a sandwich panel.

2. FEA with Calculix (2)

   This is the second part in a series how to analyse sandwich structures with FEA. The first part is here. If you haven’t done so, you should probably read that first.

   In that part we built and analyzed a sandwich where the core and skins shared nodes. We saw how that leads to incorrect stress distribution images because of nodal averaging. In this article, we’re going to fix that by using *TIE constraints.

3. FEA with Calculix (1)

   This is the first part of a series of articles where I hope to show how to analyze deflection and stress in structures using the free CalculiX software. I’m using version 2.17. The focus will be on sandwich structures because that is the area in which I’m most interested. Compared to parts consisting out of a single material this is a bit more tricky as we will see in this article. The main reason for using finite element analysis (“FEA”) in general is that it allows for complete analysis of problems where no integral solution exists.

   Additionally, some of the assumptions used in Euler–Bernoulli beam theory for analyzing deformation and stresses in beams and plates do not hold for sandwiches.

4. Why I think engineers should be programmers

   During my engineering education and the start of my career, a lot of design and drafting work was still done on paper. During that time I also discovered computers, and how they could be an extra tool in my toolbox.

5. Engineering category

   Although my training and career has been in mechanical engineering, there is not much about that on these pages. In this new category, I hope to remedy that.

6. Opening vim in a new terminal

   By default, when you open vim it runs on the current terminal. When running X11, I want to start it in a new terminal.

7. Buildworld benchmark on my new workstation

   As a real-world benchmark I rebuilt the FreeBSD OS after the most recent published vulnerabilities.

8. Writing speed on FreeBSD 12.1-STABLE amd64

   This is a repeat of the tests I ran in 2010 and 2012, on my current hardware.

   The test is …

9. Playing a sound when the battery is low

   Although I have a battery indicator on the bottom of my laptop screen I don’t alway check that often enough. That’s why I wanted to add an extra warning in the form of an audio signal. So even if I’m turned away from the laptop, it should still catch my attention.

10. Xinput settings for Kensington Expert Mouse

    Detecting possible parameters.

    > xinput --list-props 13
    Device 'Kensington Kensington Expert Mouse':
        Device Enabled (138):  1
        Coordinate Transformation Matrix (139):        1 …