The balance of my materials
should be arriving soon so I’m getting ready for a test build of the 6" combustion core outside before I begin batch rocket construction in my shop. So I’m curious what, if any, adjustments need to be made to the fuel/air mixture to account for living at 8,000 ft (2,440 M). I think the only adjustment to really focus on is the size of the primary air intake, but looking to those with
experience for guidance. For under $100 I purchased a digital kiln pyrometer rated to 2,500 F (1,370 C) with the thinking that adjusting the fuel/air ratio to introduce more oxygen will yield a hotter burn. My guess is to place the thermocouple about 2/3 of the way up the throat of the
dragon. For my actual build I plan to leave a thermocouple in the riser and place another one in the upper part portion of the bell, probably where I make my clay brick to firebrick transition. My design is all brick, no barrel.
So my questions are:
1) Should I keep my experimenting simple and limit adjusting to enlarging the primary air intake? My secondary is fixed since I purchased a tube and stub from Thomas Rubino.
2) Does it make any sense to also play with enlarging the opening size of the port?
2) It probably doesn’t matter much where I place the thermocouple in the riser as long as the position remains constant, but I’m curious to see the temperature in the hottest part of the flame. Where in the riser is the best spot to place the thermocouple?
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