http://www.riel1.net

This guy has a lot of burner designs, they are meant for forges. For
open-air heating I don't know how they'll do, they're meant for use in
a highly insulated forge box. My opinion is that, if you want to get
the job done, go rent/buy an oxy-acetylene rig. If your aim is to
make burners, go full speed ahead. What's your time worth?

Stan