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  #1  
Old 10-03-2001, 12:41 AM
Blown & Injected Blown & Injected is offline
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If one has a large hot fire with a coil of copper tubing being heated by the fire, is there an easy way to make use of the energy from the fire to move water through the hose that is connected to the ends of the tube?

Perhaps if one hose end is placed a bit up stream and the other end attached to a shower head...
or
How about a small pool with one hose end through the wall of the pool near the bottom - to the fire - and then return hose over the top of the pool wall.

TIA,
Steve
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  #2  
Old 10-03-2001, 03:19 AM
mmmiiikkkeee mmmiiikkkeee is offline
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No, it won't work at all; IF I'm imagining your setup the right way - you're talking about heating water in the copper coil so it will loose density, rise up (and out the other end), and draw more water in from the pool right? Both ends of the hose would be open to the outside air pressure, and water just getting hot wouldn't provide enough force to overcome the air pressure over the high end. The hot water in the tube would hardly expand any, and the result would simply be the pool level rising up a few microns by the water seeking it's own level on both ends. If you had a sealed circle of pipe (full of water), and heated it at say 3 o'clock, the water would slowly start circulating counter-clockwise through the pipe, and start slowing down once it got to a roughly uniform temperature throughout. But it's hardly at pumping pressure, and if you open the ends up to the atmosphere, the water won't go anywhere. Radiators work because they're sealed, but the same principal wouldn't work for the setup you describe if I understood it correctly. Just grab a bucket and dip the water out - you can outperform a lot of small water pumps with just a bucket and arms as far as volume of water moved over time!
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  #3  
Old 10-03-2001, 10:42 AM
erislover erislover is offline
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mmmiiikkkeee, I wouldn't be so quick to judge. Coffeemakers obviously work like this, though they have the aid of a check valve and fluid pressure.

Firstly, a tube can move water all on its own by siphoning action. All you would need to do is use the heat as a "primer" by boiling some water, condensing it, and having the condensation transfer the fluid.

The big problem is evaporating and then condensing enough water to actually "prime" the siphoning action. That does present a very large practical difficulty.

The best you could hope for is not actually "pumping" the water but using fluid pressure to get it to the "hot" part of the tube, and setting it up, basically, as a condenser tube from there on out.

Possible, but impractical. Priming a rubber tube to siphon the water out would be much easier.
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  #4  
Old 10-03-2001, 06:09 PM
mmmiiikkkeee mmmiiikkkeee is offline
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True you can siphon water, but not from a low spot to a high spot; I'm pressuming the water source would be lower than where you want to pump/siphon it to. You would indeed need some serious heating action to prime a siphon with condensing water, and even then, you wouldn't be siphoning (or pumping), just condensing steam down a spout... you'd end up with a "drip.........drip.........drip" kind of water flow after spending several hours setting the apparatus up and buring half the Sherwood forest to move enough water for a cup of tea (hence the impractical part). For the equivalent amount of time, effort, and materials needed, you'd be able to just bail 100 gallons out of the stream by hand instead. You could however purify your water pretty good using the coil and condensation method.
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  #5  
Old 10-05-2001, 07:53 PM
Blown & Injected Blown & Injected is offline
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HI

I was thinking if the inlet was about 200 feet up stream, there might be enough "down hill" flow to bring the water to the coil.
Or.
If a tube were sealed near the bottom of the wall, near the floor, in a small pool, the pressure at the entrance should force the water to the coil.
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  #6  
Old 10-05-2001, 09:23 PM
mmmiiikkkeee mmmiiikkkeee is offline
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In the case of the sealed tube on the outside bottom of a pool, yes; the water would flow through the coil and up the pipe to the other end, but the water flow would stop when it reached the same height as the surface of the pool. If your outflow end of the pipe is lower than that, water will flow out - until the pool drained down to the level of the outflow. You wouldn't need to heat the water, as it would just be draining due to gravity. You could use the fire to make heated, but still "gravity-flow" water. Same goes for the stream, as long as your intake was higher than your outflow (like from a stream with a few falls or a steep gradient), the water would go through the coil and come out the other end no fire needed; but there you would just be siphoning from the stream. If the stream were more level but moved fast enough, you could hold a very short peice of pipe on an angle in the flow and have the stream push the water up through it (similar to how water bombers fill up), but you'd only get a few inches of lift. Put a 200' long 1/2" pipe into the fast flow and practically all the power from the water velocity would be lost through friction along the inside of the pipe and it wouldn't rise any higher than the stream level. In any of the above examples, the only thing the fire and coil would do is make the water warm; as I'm imagining the setup you won't be able to actually pump the water by heating it a copper coil. (I've worked in all kinds of aquaculture sites where they use stream and ground water in high-pressure and gravity flow applications, and I'm pretty sure this setup wouldn't work as intended)
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  #7  
Old 10-06-2001, 07:56 AM
kanicbird kanicbird is offline
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if your pool pipe's intake and outlet is below the water and the heated water would rise then you would get natural convection in the water and it would rise and circulate.

as for the camping - not really your best bet would be to take the boiled water (steam) and direct it into the pipe, let it condense up high in a collector - but this would be very slow. also you could put a pool above you as stated above with the inlet and outlet pipe below the water level have the pipe run down away from the fire, cross to it horizontally and rise through it. YOu would get natural convection heating the pool water then you could drain the warm water.

there are better ways to take a shower in the woods but that's not what you asked.
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  #8  
Old 10-06-2001, 01:15 PM
Captain Amazing Captain Amazing is offline
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Alternatively, you can wrap someone up in the copper coil and hang him over the fire until he tells you where he hid the hand pump.
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  #9  
Old 10-07-2001, 10:03 AM
Blown & Injected Blown & Injected is offline
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Thanks for all the replies!!!!
Yeah, I know there are better ways, but the people I occasionally go camping with seem to try to make the campsite even more home-like than home. A pool is on the list of things going on the trip this fall.
Somebody will even bring a kitchen sink so we have an answer for those that may wander by and exclaim "you brought everything but..."

Personally, I kinda like the peace and quite over the generators, stereo systems, wide screen TV/satellite, but the recliners are way better than sittin' on a cooler.

I never really thought the the heat would move that much water. But I also thought has anybody really tried? The weight of the water from a couple hundred feet of hose - the heat - steam - the difference in density may help with some lift - I don't know - But I was hopeing to find somebody like mikeee that has been there.

Even if if works, will it heat enough water for a pool? I doubt it. A spa would be best as it heats the water.
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  #10  
Old 10-08-2001, 02:31 AM
mmmiiikkkeee mmmiiikkkeee is offline
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You should make yourself a sauna - only takes a tarp and some long branches tied into an igloo shape. We made one of these on N. Vancouver Island a few years back, and it worked great. Grab a bunch of rocks and leave them in the fire for a few hours. One person scoops them out with a shovel and puts them into the center of the hut... it's cool cause it's very dark inside and you can see them glowing for a few minutes. You know how the rest works... just keep your feet in!!
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  #11  
Old 10-08-2001, 11:06 AM
Scylla Scylla is offline
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Get two drill pumps that fit garden hose.

Attach the inflow hose of pump one to a large sealed container full of water. Leave the outlet open. Attach the shaft of pump one to pump two, you'll need to improvise a jog, but it should be pretty easy.

Run the inflow hose from pump two to the stream, and the outflow hose to wherever you want water. Prime pump two, and heat the water under pump one.

Steam pressure will turn pump one and pump two which is attached to it will spin as well, delivering your water.


Or you could use a bucket.
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  #12  
Old 10-08-2001, 12:07 PM
Jinx Jinx is offline
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A Different Approach

I'm not sure if this would work, but it could yield short-term results. As suggested, prime the coil with some water and then heat. The residual water would create steam. Then, pull the coil out of the fire. The condensing steam should create a small vacuum effect.

Maybe this vacuum pump effect works best with a closed system. If so, maybe possibly placing a cork (or rubber) stopper over the discharge end of the coil would help. Once the pressure builds enough to pop the cork, stop heating and let the condensing vapor provide the vacuum to siphon the water upwards.

Again, this might take some practice and good timing. Also, make sure the coil is designed to take a little pressure build-up, or the coil will "pop" before the cork!

Just thinking once again w/o a safety net...
- Jinx
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  #13  
Old 10-08-2001, 12:23 PM
Jinx Jinx is offline
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Quote:
Originally posted by mmmiiikkkeee
True you can siphon water, but not from a low spot to a high spot...
Not sure what you mean by this remark. Siphoning IS the act of moving water from a low spot to a high spot, otherwise you'd just have gravity flow! (i.e.: Moving water from a high spot to a low spot.)

The siphon effect is by some vacuum source serving to lift the fluid as the vacuum is filled. A hand-pumped siphon with a bulb on one end is an example where the squeezed bulb is evacuated, and water is lifted upward into the bulb upon release.

Even if the final destination of the water is below the water level of the source, I'd picture a siphon lifting the water to some high point (even if just a few inches above the surface of the source's water level) and draining it into a bucket, for example, positioned below the source.
- Jinx
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  #14  
Old 10-08-2001, 12:41 PM
Jinx Jinx is offline
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Quote:
Originally posted by Jinx
...Siphoning IS the act of moving water from a low spot to a high spot...
One note to clarify: There is something known as a reverse siphon effect when a fluid moves in the opposite direction as desired. For example, I was trying to drain a waterbed bladder into a large basin below the waterbed's water level via a hose. By pushing on the bladder, water moved into the hose, but when tehe pressure was release, the evacuated space in the sealed bladder drew water upward through the hose and back into the bladder. Yes, it's a siphon, but it's sometimes said to be a reverse-siphon since the effect is opposed to the result desired.
- Jinx
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  #15  
Old 10-08-2001, 01:56 PM
Trucido Trucido is offline
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I think you're mistaken, Jinx. No energy enters the siphon system, so the gravitational potential energy of the water cannot be made to increase, i.e., it can't go any higher. Yes, you can have points in the hose higher the the input, but the outflow end of the tube must be lower than the inflow end of the tube.
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  #16  
Old 10-10-2001, 02:49 AM
mmmiiikkkeee mmmiiikkkeee is offline
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Ya got to it before me Trucido. A siphon is a gravity flow system, you just use the difference in pressure to get the water moving up the hose, and then down - that's the important part... there HAS to be a down part to BELOW the level of the source you're drawing from before the water leaves the hose, or there will be no siphon or water flow. The weight of the water in the (longer) descending part of the hose offsets the weight of the water in the ascending part, and lets the water in the higher container decrease it's potential energy by flowing downhill in a round about way.
The hand squeeze pump some use to start a siphon actually is a real pump, but it's only used to prime the line.
I've drank my fair share of aquarium water from siphon hoses over the years, and felt like tearing my hair out several times when at a former job the bosses thought it would be a great idea to put a huge fish pump outside the 30' tank to pump salmon smolts out to a barge. Ever try priming 12 feet of 6" line with no valves on either end?? - think of wrestling with a 150 python and you're close
Draining the waterbed might work better if you could get a second hose into it to allow air to flow in to replace the water that moves out so you don't end up with a vacuum.
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  #17  
Old 10-10-2001, 09:50 AM
Dragwyr Dragwyr is offline
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Quote:
Originally posted by Blown & Injected
If one has a large hot fire with a coil of copper tubing being heated by the fire, is there an easy way to make use of the energy from the fire to move water through the hose that is connected to the ends of the tube?
My dad actually tried this.

When I was in Boy Scouts, my dad bought a metal garbage can and some copper tubing. He made some coils in the tubing and attached the ends of the tubing at the bottom of the can, and about 2/3 of the way up, such that the tubing was attached to the sides of the can. The idea was to put the tubing over the fire, it would heat the water and spit it out near the top and suck in cooler water from the bottom.




It didn't work.



The water never really got hot. It just sort of sat there. No hot boiling water ever spat out of the top. We ended up building a fire AROUND the can to heat the water up.
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  #18  
Old 10-17-2001, 12:39 AM
Waneman Waneman is offline
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Blown & Injected,

I found this link. It's different way of doing what you are wanting to do I think.

http://www.newageshelters.com/heater/index.html

-Waneman
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  #19  
Old 10-17-2001, 08:23 AM
justwannano justwannano is offline
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2 methods

Use scyllas method but use the heat of the fire to turn a vane as in a windmill positioned above the fire. Power the pump with that apparatus.put your coil in the fire to heat your water.

Method 2
Make the kids carry the water and put mmiiikkkkeeees hot rocks in the pails to heat the water.
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