First off this forum rocks. I have learned tons from it. My older smoker projects were just built with little to no science applied so after reading on here (mostly about 250 gal) im going to use engineering to my advantage.
1) How much operationing temp (heat up, maintain, and consumption) will differ from a 250 gal to a 500 gal?
2) The major twist I am wanting to work in is a propane assist in the fire box. Not just to start the wood in the fire box but after a good 4-5 hrs of smoking I dont think you get any more smoke imparting in the meat so you can finish off your cook with propane heat and keep the temp even and level with no changes. If someone has some design tips on this or be able to point me in a direction it would be greatly appreciated. To make things more complex it would be nice if it operated while driving down the road since this is going to be a trailer mounted model. Yes I am aware of the perils of this is the flames go out and gas it could make a nice boom boom. I am trying to avoid this with proper design. If it doesnt turn out to be something the propane assist will work its not a deal breaker. I'll just use it when not driving.
3) I think I have most of the calculators that are posted here but if there is something that I need a heads up to avoid any issues that people make in design.
I will be documenting this every step of the way so others can help use the info