Computer-Aided Engineering in Linux

     Engineers are some of the heaviest number-crunchers around. If you are a grad student, post doc or undergrad, you usually get whatever is lying around as your work machine. Also, depending on how inflexible your local IT department is, you may be forced to use one of the commercial operating systems around these days. What are lowly students to do when they need to do heavy computational work? You may be interested in looking at . This project provides a live CD that gives you all the open-source tools you might need for your engineering work. And, because it is a live CD, you can use it without touching the local drive of the machine you are using.

Like all live CDs, it has all the standard Linux desktop tools you should be familiar with, including Firefox for Web browsing, Evolution for e-mail, and OpenOffice.org for word processing, spreadsheets and presentations. Along with these applications, there are dozens of others to help with all your number-crunching work. The most recent versions are based on Ubuntu, so it should be a fairly comfortable environment for most people. Be aware, however, that you can't use the usual software update mechanism in Ubuntu. Many of the packages in CAELinux are compiled from source and optimized, so you don't want them being overwritten accidentally by any packages provided by Ubuntu.

Welcome to CAELinux

A really well written introduction to CAELinux is available right on the desktop, called "Getting Started". You should start here if this is your first step into the world of CAELinux.

Getting Started

Last month, I looked at OpenFOAM in this space. CAELinux includes a full install of OpenFOAM. It also includes another fluid dynamics program called SALOME. This program provides a full graphical interface that takes you from forming your problem, to modeling, to calculation and through to analyzing your results. This might be a good choice for those who are more comfortable with a GUI. A series of examples on the desktop are available that provide a walk-through of the program, showing each of the steps as you go through.

CAELinux Tutorials

As you can see, the tutorials walk through several common simulations, like modeling flow through a pipe. These can provide great starting points for many people.

If your work leans more toward data analysis, several popular packages are available. For all of you Matlab addicts, there is Scilab. Scilab provides the same types of functions in an environment familiar to Matlab users. There also is Maxima, which provides tools more from a mathematical background (for example, analyzing functions and doing calculus), as compared to Scilab's approach of working from a matrix background (such as looking at data analysis). Maxima has several front ends available. The default one in CAELinux is wxMaxima. If you are doing really heavy statistical analysis, there is R. The real power of R is the CRAN repository, and a fair amount is available out of the box. R also has several graphical front ends. CAELinux provides two: R Commander and RKWard. If you are doing work more along the lines of pure mathematical analysis, there also is Octave. The default GUI available within CAELinux is QtOctave. In all of these cases, text-based interfaces also are available, if you are an old-style computer user who prefers that kind of thing.

Several software packages exist for applications other than CFD or statistics. If you need to do finite element analysis, there's elmer. It provides both a text-based and GUI interface. There also is JavaFoil, available for doing analysis on airfoils and wings. If you are designing electrical circuits, two packages are available. Electric is a CAD program that helps you lay out a circuit. And, once it is all laid out, you can use PCB Designer to get it set up so you can etch a board to make it real.

This is all fine and good if you can use a standard toolset in your work. But, what if you need computing power for really cutting-edge research? CAELinux provides the entire GNU toolset. This means you have everything you need to go ahead and start developing your own code. All of the most common scientific and engineering libraries, like gsl and LAPACK, are available. If you are working on really large problems, MPI and openMP also are available. This way, you can develop a parallel programming solution if that is what your problem needs.

Once you have finished all your calculations, an important part of data analysis is graphical analysis. There is something visceral and instinctive about actually seeing your data represented. To this end, CAELinux provides several packages. If you simply want to plot your data, you can use programs like grace and LabPlot. If you want to do more complicated data analysis, you have programs like G3Data and OpenDX Data Explorer. These programs have lots of functionality that can be used to look at your data graphically. If you are doing CFD work, several programs for visualizing your meshes are available. So, you have your choice based on what features you need.

The last option to look at this month is using CAELinux in "the cloud". Cloud computing is one of those sexy terms that gets used a lot in marketing, but it sometimes doesn't really give you anything useful. In this case, there really is something substantial being offered. CAELinux now can be run as an application under Amazon Elastic Cloud Computing. You can now run, on demand, as many nodes as you like, each having eight cores and 64GB of RAM. For people who don't have the resources to run their own clusters, but need more than what a desktop can handle, this can be a very attractive choice. It definitely is worth looking into as a possible option. You can find more information about EC2 at , and the CAELinux Web site has a very good set of instructions to get you up and running.

As you can see, CAELinux provides a lot of power and functionality for doing computational science. Because it is a live CD, you can run it on essentially any 64-bit machine without touching the hard drive. But, you also have the option of installing it on the machine if you are allowed. Download an ISO and start playing with it to see just how much work you can do with it.