Open Source Ecology Heat Exchange Coil Winding, 3 Feb 2012

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From YouTube: Typical steam generator design

Description

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Okay, so here's the design of a typical boiler- cold water in from the bottom of the water, comes in the bottom and it's still in a liquid form when it comes in so you don't need as much volume as the water heats up.

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It travels upward, gets hotter and harder. You start forming steam bubbles. Well then, that expands, so you need a a larger surface area, a larger volume, so that can expand. So you start with the small tubes. You go to a larger tube. Okay, it gets hotter.

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You go to an even larger tube. Okay. Now, once you've done that.

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uh um A quick note here: you notice the center is plugged. Okay, that's because the the heat's gonna the fire, the heat's gonna, have a tendency to follow the path of least resistance. Okay, so you plug that, because you're going to get a lot of wasted heat to shoot right straight through that hole, uh-huh! Okay, so you plug that that forces the air to go around the coils okay. So all right now.

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The water and the gases are getting hotter and hotter and they're expanding.

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Then you pump it into this water wall after the super heater. No superheater is the last thing. Okay, this is where the combustion chamber comes in, because you get even more heat transfer, because this is the next to the hottest area, so the water is rising. Turning into steam, expanding comes up the water wall, out of the water wall and back down to.

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The super heater, typically, your super heater- is made of a heavier material like the schedule, 160 black, pipe or stainless. This is stainless, it'll take much higher temperatures and it's stronger.

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However, the drawback with stainless steel is your heat. Transfer characteristics are not as good as black iron pipe that's. Why so many people use black iron instead of stainless.

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Now, if you have a hotter fire, you can use stainless because then it doesn't matter about your heat transfer characteristics. You have a hotter fire, so the heat will just transfer automatically when you say hotter. What temperature 2300 degrees.

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With a pellet burner,.

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Unless you really charge it with a lot of air you're, not gonna, get eight or nine hundred or a thousand degrees, or you may max out at a thousand degrees with your liquid fuel burner, you can get 2300 degrees fairly easily, but you still have to have the right amount of fuel air ratio.

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Otherwise you get the problem of carbon, carbon and uh unburned fuel and then it settles on your coils and then you lose your heat transfer characteristics.

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So anyway, we've come up the water wall. This is the water wall.

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It's gathering heat, it's it's it's absorbing heat from the combustion chamber which gets it even hotter. Well then, you can't, we don't have the transfer tube here, but it came up and it came outside the boiler and then back in to the super heater.

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The super heater basically sat in here and in and out, let's see I gotta find well, unfortunately, this is disassembled, but this this there would be a space in here where this. This uh came out the side.

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So now from up here, we ran our our steam into the super heater and this is directly underneath the flame coming out the bottom of your combustion chamber- okay, so this is sitting here and you just you've got you've got this intensive heat touching these coils.

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And it was so intense.

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And that that's why we got the blow out of this coil, because the super heater was on top of this and was basically protecting it, but the flame was still so hot and the boiler was so old that that just expanded because of the internal pressures, because your your your steam temperature and your steam pressure are directly related.

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Okay, water boils at 212 degrees, well at 212 degrees. You can develop between 150 and 200 psi esteem as you raise that temperature and go 3, 4 5, 6, 7, 8, 9, 1, 000 degrees. The pressures inside your boiler are relative, four, five, six, seven, eight, nine, a thousand psi.

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So the heat is coming down on this superheater and that's where it quote: the term dries the steam, the drier, the steam. You have.

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The more efficient your engine is going to run the less condensation you're going to get inside the engine, because if your engine is closer to the to the boiler, you have less heat loss before you get to the engine causing less condensation but as as the steam enters the cylinder of the engine and expands that causes condensation in and of itself, because it's expanding into an area.

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With a massive pressure drop because it comes in at say, 500 psi. Well, as the cylinder travels down, you automatically have more valve more volume. The heat exp, the steam expands even further, but then it cools it's just a natural reaction or a natural phenomenon.

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So you exhaust the steam, your your piston comes back up and you start all over you inject the valve opens you inject the high pressure steam. It expands, causes the rotation of the engine or the motion. The reciprocating motion steam cools as it expands. Well then, after it exhausts it, the pressure drop is even more even greater. Then it starts to condense even more.

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That's why we reclaim the steam to make it more efficient. You reclaim the steam drop it into a hot well through a condenser and then into a hot well, but then you have the problem of the the engine, oil and the steam oil being mixed with the steam. So you need a separator to get that out.

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Now it's possible to get your steam too hot for them to have what they call a and I'll show you that, on the new boiler.