Is very interesting simulation prof lookang any way
I modified interface  ;)

Hard Disk Gas model displays a two-dimensional gas made out of hard disks.
Particles are initialized with a speed v=1 in a random direction and move with constant velocity until a collision occurs. 
You can modify this simulation if you have Ejs installed by right-clicking within the plot and selecting "Open Ejs Model" from the pop-up menu item. 

/htdocs/ntnujava/ejsuser/37048/users/br/ahmed/HardDiskGaswee04_pkg/HardDiskGaswee04.propertiesFull screen applet or Problem viewing java?Add http://www.phy.ntnu.edu.tw/ to exception site list
Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop. This work is licensed under a Creative Commons Attribution 2.5 Taiwan License
Download EJS jar file(944kB):double click downloaded file to run it. (4 times by 4 users) , Download EJS source (1 times by 1 users) View EJS source