Post by hinotama on Dec 9, 2011 12:27:30 GMT -8
I have thought and thought about this and sketched it. It is all pretty elaborate and quirky.
I want to make a system that heats with a rocket stove, stores some heat in solid mass, and then takes off heat to water stored around a greenhouse. The greenhouse will stand next to my existing home. I want to system to be unobtrusive and safe. The main goal will be to keep the beds going during Dec--Feb and give heat to the main home. I want exhaust to be cool. No vertical chimney.
What seems to be very much against the grain of this group is that I plan to use fans and pumps to a reasonable degree, and use a tiny bit of electricity to do that. Probably 60W.
Here goes.
The rocket stove will be about 4 feet high, with the riser either cast or formed by a stove pipe or simply rectangular brick. It will lead to a "bell" that will probably not be a barrel. I want to use a masonry?metal? headspace, heating some mass on top of that.
That will form a pillar with a big bulge on the top, or something like that. Then, on the other side of that riser/chimney structure will be a "chimney" though which I plan to run metal pipes (steel 3/4 diam thin wall) carrying "cold" water. The hot air will rush down from that headspace, heating that water as it cools. That warmer water is pumped off to a basin and replaced with cold water, etc. Then that cooler air will run through a long horizontal chimney at floor level around the greenhouse and exit from the greenhouse.
Result: hot mass at the headspace, water that circulates becoming progressively warmer (system less than 200 liters/ 50 gallons), some residual heat from the "chimney" at the floor, and exhaust that is quite cooled.
Two features are the use of exterior air piped in, used instead of warmer interior air, and the steel pipes used for the water system, which will be half in the chimney and half out of the chimney. I plan to seal only part of them into the chimney and the hot air. The whole water system is an open system that functions by simultaneous siphoning among about 10 tanks, with water pumped only through the chimney coil itself.
It all sounds ludicrously challenging and silly, but let me explain that I already have all of these materials. I expect the cost to be... close to zero. And that is kind of the fun part.
Another thing is that I don't necessarily want any part of this to be crazy hot. For instance, I am worried that the headspace material will get to 500C or so, and I don't want my water pipes to get to 200C or thereabouts. For that reason, I plan to build smaller fires (narrow riser?) and circulate water rapidly to scrub that heat from the chimney.
So there is my plan. What do you think?
Specific questions:
1. The riser diameter should be... what?
2. What do I cap off that headspace with? I thought about using a large aluminum pot mortared or set into clay? It will melt right? or do I cap it with brick? Or an upside down large ceramic flower pot or cast iron pot? Or a slab of steel plate of an inch thick? or a rock?
3. Having the rocket riser on one side of the pillar to the head space and the "cooling tower" on the other side of the pillar is going to require some great insulation on one side, and conduction on the other, but it can be done, right?
4. What if the riser going to the headspace is, say 6 inches, but the holes leading down from the headspace are two holes of say, 8 inches each? Does this slow the whole system? Or does it accelerate the flow? Heating in a narrow diameter with small surface area makes insulation easier, but cooling with a large diameter means more surface area, right?
I want to make a system that heats with a rocket stove, stores some heat in solid mass, and then takes off heat to water stored around a greenhouse. The greenhouse will stand next to my existing home. I want to system to be unobtrusive and safe. The main goal will be to keep the beds going during Dec--Feb and give heat to the main home. I want exhaust to be cool. No vertical chimney.
What seems to be very much against the grain of this group is that I plan to use fans and pumps to a reasonable degree, and use a tiny bit of electricity to do that. Probably 60W.
Here goes.
The rocket stove will be about 4 feet high, with the riser either cast or formed by a stove pipe or simply rectangular brick. It will lead to a "bell" that will probably not be a barrel. I want to use a masonry?metal? headspace, heating some mass on top of that.
That will form a pillar with a big bulge on the top, or something like that. Then, on the other side of that riser/chimney structure will be a "chimney" though which I plan to run metal pipes (steel 3/4 diam thin wall) carrying "cold" water. The hot air will rush down from that headspace, heating that water as it cools. That warmer water is pumped off to a basin and replaced with cold water, etc. Then that cooler air will run through a long horizontal chimney at floor level around the greenhouse and exit from the greenhouse.
Result: hot mass at the headspace, water that circulates becoming progressively warmer (system less than 200 liters/ 50 gallons), some residual heat from the "chimney" at the floor, and exhaust that is quite cooled.
Two features are the use of exterior air piped in, used instead of warmer interior air, and the steel pipes used for the water system, which will be half in the chimney and half out of the chimney. I plan to seal only part of them into the chimney and the hot air. The whole water system is an open system that functions by simultaneous siphoning among about 10 tanks, with water pumped only through the chimney coil itself.
It all sounds ludicrously challenging and silly, but let me explain that I already have all of these materials. I expect the cost to be... close to zero. And that is kind of the fun part.
Another thing is that I don't necessarily want any part of this to be crazy hot. For instance, I am worried that the headspace material will get to 500C or so, and I don't want my water pipes to get to 200C or thereabouts. For that reason, I plan to build smaller fires (narrow riser?) and circulate water rapidly to scrub that heat from the chimney.
So there is my plan. What do you think?
Specific questions:
1. The riser diameter should be... what?
2. What do I cap off that headspace with? I thought about using a large aluminum pot mortared or set into clay? It will melt right? or do I cap it with brick? Or an upside down large ceramic flower pot or cast iron pot? Or a slab of steel plate of an inch thick? or a rock?
3. Having the rocket riser on one side of the pillar to the head space and the "cooling tower" on the other side of the pillar is going to require some great insulation on one side, and conduction on the other, but it can be done, right?
4. What if the riser going to the headspace is, say 6 inches, but the holes leading down from the headspace are two holes of say, 8 inches each? Does this slow the whole system? Or does it accelerate the flow? Heating in a narrow diameter with small surface area makes insulation easier, but cooling with a large diameter means more surface area, right?