Wave Physics

Hello everyone. I’m busy with our 3rd year university project and we’re doing an explosion wave simulation. The thing is I’m not doing an engineering degree but an IT one and have no heavy knowledge on physics.
I was told that explosion waves and water waves are almost identcal in their behaviour so I’ve used the algo found in the Programming Gems text book.
Everything works fine except for the waves bouncing off the edges. I’ve been trying for so long to get that bouncing to stop but all my attempts failed.
I’ve then decided to post on http://www.gamedev.net/community/forums/topic.asp?topic_id=343564 at Gamedev.net.
Some of the guys there tried to help me but I still fail to understand something and I really need to finish this part of our project sothat I can tend to other things.

Please I would really appreciate the help from you guys as our project uses OpenGL to draw the editor and simulation.

Thanks