Dan Dronberger wrote:sitting listing to the rmh. I hear a low tone (the rocket sound) but a definite low tone.
I added a wedge brick (pic) as the first brick of the burn tunnel. Idea came from picture of the castable dragon heater core.
The profile of a J tube is similar as a whistle, just need to tune the fuel to air flow.
Question is. Does tuning of the SOUND of the rmh. Have any thing to do with the burn?
Has this idea been tested?
Most owners use the sound of their heater to know when to re-load or adjust the fire - since the visual isn't as convenient a clue as on some other stoves and fireplaces.
In general, a more definite sound of air movement indicates stronger draft and a more effective burn. This is the 'rockety' sound a lot of people love to hear.
There are upper limits where more draft just cools the fire with too much air, but these are rarely encountered in most home heaters I've seen.
Pulsing can indicate an air-starved fire; while it's fun to hear, it should usually be followed by opening up more air supply if possible (don't choke the fire just to hear it pulse.)
Mostly it seems to be something that owners "play it by ear," learning to interpret the sound of their own stove, and calibrating by checking for smoke or odors in the exhaust. The sound of a happy stove becomes familiar, but it is slightly different for each stove. The type of fuel (dense hardwood vs. softwood), the size of kindling or logs used, the roughness or shape of the brick firebox, the outdoor temperature and weather conditions, and the exit drag or draft from the stove's design, will all factor into the stove's operating sound.
It would be interesting to discover a more robust relationship between the sound and burn - but there are so many variables it might be difficult to prove.