<!DOCTYPE html> <html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body text="#000000" bgcolor="#FFFFFF"> Hi, When discussing with Physics teacher at my school, its appears gas simulation is something desired. There are some simulation out there, but they keep mentioning me it is a nice tool to have. So I gave a shoot and start the implementation of a DKM[1] for the Dybo project. A first iteration was a very naive, kind of billiard: <a class="moz-txt-link-freetext" href="https://mamot.fr/@drgeo/115577138308536197">https://mamot.fr/@drgeo/115577138308536197</a> Then hack some energy transfer from the wall: <a class="moz-txt-link-freetext" href="https://mamot.fr/@drgeo/115598616477391933">https://mamot.fr/@drgeo/115598616477391933</a> <a class="moz-txt-link-freetext" href="https://mamot.fr/@drgeo/115600731271105530">https://mamot.fr/@drgeo/115600731271105530</a> However this implementation was not correct from the thermodynamic perspective, so I implement a real diffuse energy transfer model: <a class="moz-txt-link-freetext" href="https://mamot.fr/@drgeo/115623761342500850">https://mamot.fr/@drgeo/115623761342500850</a> This gave a more or less realistic simulation of ideal gas. The next challenge was to have inter-atomic potential to be considered: atom can be attracted or repulsed from each other. The Lennard-Jones law was used. The tricky part was really the scale and simulation step time: Atom can get crazy unrealistic velocity <a class="moz-txt-link-freetext" href="https://mamot.fr/@drgeo/115669231450451191">https://mamot.fr/@drgeo/115669231450451191</a> because of not small enough simulation time. With a fined tuned simulation time and Morph step time of 100Hz, the result are quite interesting: <a class="moz-txt-link-freetext" href="https://mamot.fr/@drgeo/115669511921472246">https://mamot.fr/@drgeo/115669511921472246</a> The final model has both diffuse energy transfer from the wall and inter-atomic potential calculus. Again, the Cuis environment proved to be extremely helpful to fine tune the algorithm. Of course this DKM can be used from a Dybo document, as seen there with another DKM: <a class="moz-txt-link-freetext" href="https://mamot.fr/@drgeo/115400315017925601">https://mamot.fr/@drgeo/115400315017925601</a> The aims is develop hundreds of such modules. Hilaire [1] <a class="moz-txt-link-freetext" href="https://github.com/Dynamic-Book/doc/tree/main/4-Explanations/200-Dynamic-Knowledge-Models">https://github.com/Dynamic-Book/doc/tree/main/4-Explanations/200-Dynamic-Knowledge-Models</a> <pre class="moz-signature" cols="72">-- <a class="moz-txt-link-freetext" href="http://mamot.fr/@drgeo">http://mamot.fr/@drgeo</a></pre> </body> </html>