My students and myself have had some good luck with the open source and free software package Acoular. We used it to try and visualize the acoustic source distribution within a tornado. It worked fairly well, but of course the technique is dependent on the quality of data used. This is generated by CFD simulations usually. CFD for acoustic analysis needs to be high-resolution and have small time steps. This is rather complicated by the fact that these simulations take more time than others. At the end of the day, the program produced some aesthetic images.

Silicon Graphics Tech. Advice

This amazing website contains lots of great technical information on SGI. Many of my students have no idea what SGI is, which is unfortunate, but a quick Wikipedia read is just a Google search away. I grew up with some SGI machines, where I remember running some of my first CFD codes on late at night. SGI might not always be the tech. leader in performance, but their machines had the most style! That should count for something when today Macs have done so well on the open market.

On Teaching Philosophy

You asked me how should I best teach them. Should I teach them from the point of view of the history of science the applications? My theory is that the best way to teach is to have no philosophy. We must be chaotic and confuse them in the sense that you use every possible way of doing it.  That’s the only way I can see the answer.  So as to catch this guy or that guy on different hooks as you go along. And during the time when the fellow who was interested in history is being bored by the abstract mathematics. On the other hand the fellow who likes abstraction is being bored at another time by the histories. You can do it so you don’t bore them all, all the time. I really don’t know how to do it. I don’t know how to answer this question of different kinds of minds with different kinds of interests. What hooks them on, what makes them interested, how do you direct them to become interested? One way is by a kind of force, you have to pinch this course, you have to take that examination. It’s a very effective way many people go through schools that way this may be the more effective way. I’m sorry, after many many years of trying to teach and trying all different kinds of methods, I really don’t know how to do it.

Prof. Richard Feynman, Ph.D., Altadena, California, March, 1966.

Andrei Nikolaevich Kolmogorov – A Digital Tribute

The great Academacian Andrei Nikolaevich Kolmogorov, who pioneered turbulence theory and started the Russian school, has fans overseas (big surprise!). I always wanted to create a website with a collection of his pictures, portraits, important articles, and anything else I could find online or off. Someone of course beat me to it! A recommended browse for those who have interest in the greatest mathematician that ever came out of Russia.

Kolmogorov Library Project
Prof. Kolmogorov surrounded by his supplicants.

LibriVox – Free Open Audio Books

Many people have kindly volunteered to create their own ‘books on tape,’ much like those we heard as children from our local library. Though tape is gone, we can now hear free digital ones from anywhere in the world. There are some good readers of traditional texts. Most are fictional, and worth listening to on a quiet afternoon when the mind needs a rest from research.

HiFiLES High Fidelity Large Eddy Simulation

My students and myself were impressed with the Stanford University release of HiFiLES, a large-eddy simulation solver for turbulent flows. We were able to use it successfully in our Office of Naval Research Grant. In fact, our modifications were released for free with an in-built acoustics solver. These codes are free of charge to use and available to the community. One can read our use of the solver at Grab the source and try it yourself on GibHub at