MRE Heaters

When I was younger, we played with the heating packets from MRE's (Meals, Ready to Eat - Military field meals). My favorite thing to do was to put a pouch inside a plastic container (with a screw-on lid), add water, tighten the top, and wait for the large boom. Here's my question: The heaters release moderate amounts of hydrogen gas once water is added. Of course, with an enclosed container, it will quickly reach pressures adequate to blow a bottle apart (wear eye-wear). But once I joined the military we would add a flame source, so we could see just how large the blast was. I wasn't so sure that flame would actually add anything to the gas explosion. They were sure of it. Is anyone aware if: The presence of flammable gas (exploding from a plastic bottle) with an external ignition source would increase the blast? Or maybe just add another factor to it? I'm sure somebody knows. Every once in a while, though I've been out of the military for about 4 years now, I still find it surfacing from my friends. Just curious.

NachoMahma9 years ago
. If I understand the scenario, you will end up with two "blasts." You'll get a "pop" when the gas pressure ruptures the plastic container and then a "boom" when the H2 ignites. Probably close enough together that they sound like one explosion.
Goodhart9 years ago
With the first scenario, you have released gases, with the second, those very gases are being burned and extra heat (thus expansion) would be produced; theoretically. I have heard balloons with hydrogen in them give off a mighty BANG, that is much louder then the balloon's "pop".
that is an interesting question. I think it would add to the explosion, not the inital bottle bursting but to the grand explosion because the air would mix better with the hydrogen then you have the expanding gasses from the fire burning the air/fuel mixture. I would like to try it out but where i live the MPs would be called out.