dabay
New Member
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Post by dabay on Jul 17, 2014 6:07:49 GMT -8
Hi! i'm so excited finding a cool forum discuss all about rocket stove! I'm interested to build one, I please your guidance.. so, did you fill the tin barrel with water or it just a protector? I try to sketch the scheme of your sketchup view, is it like this? ![]()   so the hot air from the chamber do steam the tin barrel till hot and the copper pipe suck the hot water. What if i eliminate the copper pipe using regular hot water tube pipe? coz i bit worry if copper will produce toxic things if we boil it? |
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Deleted
Deleted Member
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Post by Deleted on Jul 17, 2014 6:47:06 GMT -8
Copper will produce toxic things only if there are aggressive chemicals in the water.
Coils of other materials would have to be longer, non metal coils a huge lot longer.
Plastic tubes can withstand 100°C only for a short time.
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dabay
New Member
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Post by dabay on Jul 18, 2014 0:44:35 GMT -8
@karl, I using ground well water, so far the water is clear and no stink, but another houses using central water pipe which goverment provide for the citizen, it's certified clean. Will it be ok if I using ground water to the boiler?
so the 2nd scheme seems to be the correct one i guess
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Post by peterberg on Jul 18, 2014 1:02:18 GMT -8
so the 2nd scheme seems to be the correct one i guess I am sorry to say, neither are correct. The water in the barrel is open to the air, the coil is connected to the mains supply and is therefore pressurized. |
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Post by peterberg on Jul 18, 2014 1:50:55 GMT -8
Here's the basic design of such a water heater as drawn and built by Tim Barker from New Zealand.  As you can see, the coil is pressurized and the water tank is open with an overflow to the outside air. The tank is at the perfectly right place, above the rocket heater. The hot gases are streaming around the tank and the coldest gases are exhausted at the lowest point, opposite the heat source. As such, the insulated cover over the tank act as a bell. And here's the link to the web page where he's explaining all this. |
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Post by morgan on Jul 20, 2014 11:41:06 GMT -8
How practical would it be to have the heat riser of a basic rocket stove running up through the center of a barrel of water. In this case it would be a steel pipe welded into the bottom of the barrel and running the length of the it. A copper coil in the water at a safe distance from the sides of the riser would function as a thermosiphon. I'm thinking about doing this to heat a 100 gallon stock tank which would serve as a hot tub. I realize it wouldn't be super efficient since alot of the heat would go right up and out of the riser but does it sound fairly safe? Maybe some fins welded to the outside of the riser would provide additional heat transfer to the water.
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Post by DCish on Jul 21, 2014 12:43:22 GMT -8
Morgan: if you put the riser in contact with the water tank it would simplify the design. However, it would also sacrifice one of the core concepts that make rocket stoves efficient -- the highly insulated secondary burn area.
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Post by morgan on Jul 22, 2014 8:13:02 GMT -8
Do you mean having the water tank inside the riser? I was thinking that if the riser was going up through the water in a tank the water would act as insulation. Not so?
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Post by DCish on Jul 22, 2014 12:05:33 GMT -8
Water is a very good conductor. Think of your standard internal combustion engine where water is the coolant. A riser up through a water tank would be the most efficient way I could conceive of *cooling* the riser, not insulating it.
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Post by morgan on Jul 31, 2014 10:13:06 GMT -8
Ok, got it. Thanks for your input!
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joseph
Junior Member
Posts: 66
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Post by joseph on Sept 19, 2014 4:30:50 GMT -8
It's taken a while, but here's my concept for safe and relatively efficient water heating for showers and other domestic use. The images are taken from this Sketchup file.Credit goes to Tim Barker and Geoff Lawton over at Zaytuna Farm for pointing the way! .... Has anyone built a stove like this? - joe |
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joseph
Junior Member
Posts: 66
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Post by joseph on Sept 23, 2014 18:51:21 GMT -8
.... Seemed like the thing to do at the time.  It's a compromise. My thinking is that the water tank should be elevated to get it closer to the generation of the heat and that the greatest surface area exposed to the heat should be the tank, not the bell. .... Since the riser is insulated, couldn't you put the riser in the same bell as the water tank? That would seem to simplify the construction, and eliminate some parts also. - joe |
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Post by Donkey on Sept 25, 2014 7:38:40 GMT -8
This is JUST a visualization, the pieces can be shuffled in a lot of different ways and still work.
For that bell to work properly, the riser should attach very low down, preferably at the bottom.
We will be building a variation on this in my October 3-5 workshop. It is intended to fit into a tight space, so the bell will set atop the heat riser.
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joseph
Junior Member
Posts: 66
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Post by joseph on Sept 25, 2014 8:54:34 GMT -8
This is JUST a visualization, the pieces can be shuffled in a lot of different ways and still work. For that bell to work properly, the riser should attach very low down, preferably at the bottom. We will be building a variation on this in my October 3-5 workshop. It is intended to fit into a tight space, so the bell will set atop the heat riser. I assume that the barell will be inside the bell, and will be centered above the heat riser. How will you support the barrel? Would you use a metal frame? - joe |
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Post by Donkey on Sept 25, 2014 9:20:09 GMT -8
Water barrel inside the bell, yes. Inside and high, actually poking through the top a little for ease of access. We will build an (removable) insulated cap for it.
This stove is going where a different design existed. I have a metal stand that will hold it up, it needs some cutting down, as it's too narrow around the tank to act as a bell. THis should ALSO keep the piping for the solar backup system in proper alignment to (hopefully) just re-connect it.
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