A rocket stove is a heat appliance. We burn a fuel, it creates a heated exhaust, we use the exhaust to heat a thermal mass and sometime to heat water, cook with, and generally amaze the uninformed [of which I am becoming less so, slowly]. My reading so far tells me that the stove is a heat pump in that it pumps the heated gasses out the exhaust(?). For an ordinary wood fireplace or wood stove to draw there needs to be a temperature differential at the end of the flue such that the exhaust gasses are drawn out of the fire chamber and don't escape into the heated space. Is that true with a rocket, and if so is there a temperature that is optimal at the exhaust for a rocket stove to function properly? The reason I ask is that I want to harvest as much energy as I can from my rocket stove but don't what to design a system that is not going to function efficiently.
Here is part of my thought process - As a culture we have created a huge array of machines that use heat to do different tasks. Some of those machines use very high heat [a forge] while others use much lower heat [a hot water heater or a sterling engine]. In a rocket stove we generate heat in the numbers of hundreds of degrees. The exhaust cools as it passes along the exhaust path. Can we place heat collection appliances [heat exchangers] along that exhaust path to harvest heat at different stages in the exhaust cycle and use them to drive the heat consuming machines without destroying the efficiency of the Rocket Stove?
Bob Seagraves- Collis : And now for something different, I leave it to you to check the (possibly) Similar Threads. This time I am directing you to an earlier Thread,
Goto> Energy- Rocket Stove Mass Heater (rocketstoves forum at Permies ) In this case it was an earlier post by fellow member Alan M. that made the
connection! Next time I expect you to goto> the Permies Toolbox at the top of the page, clickon> Search and use the Google search engine to do a Permies wide search
for the information you want- Within our "pClould" Big AL !
Success has a Thousand Fathers , Failure is an Orphan
Location: Southern alps, on the French side of the french /italian border 5000ft elevation
posted 5 years ago
Bob, There's the barrel which is a radiator, which can be skipped by a bell, or removed completely for cooking. Between an open air cooking rocket and one with a bell on top there isn't much difference. Exept the heat differential tends to lessen and slow down. With a berrel, it's faster than with a bell.
Anyway, with a J tube, well made, you can push up to 40ft of horizontal tube. You can still power a vertical chimney if you have 50 C° left after that. But you could replace the 40ft of tube by prety much anything, as long as it doesn't impede with the flow of gases.
Can we place heat collection appliances [heat exchangers] along that exhaust path to harvest heat at different stages in the exhaust cycle and use them to drive the heat consuming machines without destroying the efficiency of the Rocket Stove?
As long as you don't take heat from the combustion zone, you can harvest all the heat in the exhaust until the temperature is about 140°F.
The draw is not as dependent on the presence of a steel drum as some might think. If you have bells and a good chimney, you don't need a steel drum.