my new super project

[aturner]

<blockquote id="quote"><font size="1" face="tahoma,verdana,arial" id="quote">quote:<hr height="1" noshade id="quote">Originally posted by nicholai
[br]I like that propane setup you have aturner. Thats pretty cool to use a grill tank solely for your spud gun!
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Ha! That's the spare for my gas grill. The worst thing in the world is when the propane runs out in the middle of a cookout, so I've got two tanks.

The nice thing about it is I never get liquid propane in the meter, and I always have plenty of pressure (I think it gives a steady 90psi?).

[PotatoNick]

jetpilot. You have completely misinterpreted that rocket picture! That is depicting a fuel "grain". The surface area is being depicted, not a pipe in the rocket. That fuel grain is known as "cored" the one above is just a basic cored design. It increases surface area so you burn more rocket fuel and create more thrust. This technique is used for low-impulse fuels that require more surface area to create effective chamber pressure (to induce burning) and thrust or if you want to increase the amount of thrust at the cost of burn time (since more fuel is burnt at a time).