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Converting mechanical energy to heat  RSS feed

 
pollinator
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Has anyone here put a system in place to convert mechanical energy to heat? I'm thinking along the lines of a windmill with a fluid braking system, like this:

https://solar.lowtechmagazine.com/2019/02/heat-your-house-with-a-water-brake-windmill.html

The efficiency and low material footprint are really compelling.
 
pollinator
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I have put a lot of thought into this, and done a lot of research, but I have never built anything (yet).

I live on a big hill and they were going to install (3) massive wind turbines on my land until the town vetoed the plan, so I definitely have the wind potential here. And here, my biggest living expense is in heating my home, or making hot water for domestic use,, so to use wind to heat water would behoove me.

One idea I had, was to make a windmill pull a weight (plunger) up, then drop it so that as it dropped by gravity, it would displace oil and pump it through a relief valve. I noticed the hydraulics on my tractor gets very hot when I put the hydraulic system in relief, so the oil in a closed circuit plunger system would also get hot. If that oil circulated through a bath of water, it would not take long for that water to get heated up. That could be then put to use. I see no reason in the world why it would not work. The faster the wind blew, the more volume of oil would be pumped through the relief valve, and the whole system is pretty easy for do it yourself engineering with a minimal of parts.

I have also wondered too if there was a way a cavitation heating pump could be coupled to a windmill? I know on the battleships I used to build, the Navy said you could fry an egg on the rudder of the ship, because the cavitation of the water coming off the propeller just in front of it, made the steel so hot.

I do not have all the answers by any means, but I think a fair amount of BTU's could be generated just because the wind blows so often. It seems silly not to capture it, and use other means to heat water instead.
 
Travis Johnson
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Growing up in Maine where our heating season starts on July 5th and ends on July 3rd, heat is vital to our lives. We often joke there are two season in Maine, Winter, and getting ready for winter.

But I had always heard growing up that a man invented a machine that would heat an entire house by the use of a 1/4 hp washing machine motor, but as soon as he patented it, the Government swooped in and took all his plans and paid him to keep quiet, as such an invention would destroy the consumption-driven-economy we live in.

Whether that is just crazy conspiracy-theory at its worse, or true; is immaterial. I have always wondered if such a device was a washing machine motor powering a cavitation pump? A fire house in upper state New York had a cavitation pump heater at one time to heat their firehouse, but I am not sure if it is still in use, or how well it worked.

My thoughts on this was using a windmill, then increasing cavitation speeds through pulleys and belts. Since one of my homes uses 100% hydronic heating, and low temperature water is used to heat the floor, even if wind did not provide 100% of the heat required, every btu generated would at least save on propane costs.
 
master pollinator
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I know the closed-unit electric rad heaters have oil as the operating fluid, but is there a reason to transfer the heat from the hydraulic fluid to water rather than to convert your hydronic system to run oil? Forgive me if there are obvious reasons, but it seems to me to be plausible, if it doesn't require a complete system redesign and retrofit.

If you do need to transfer the heat to water, wouldn't a finned manifold submersed in water to pipe the hot oil through be a good idea?

-CK
 
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I built a unit out of an aluminum disc and some hard drive magnets.  If you spin aluminum past a magnetic field it creates eddy currents that if held together get hot quick.  They will try to push the magnet from the aluminum.  I had a 3/4 horse maytag engine ruining it about 900 rpm.  I put a fan to blow the heat around off of the shaft the aluminum disc was on.  It works.  I suppose you could put it in a container and heat a liquid and pump it at the same time too.

Travis, I use PSI x gallons per minute divided by 1714 gives you hydraulic hp.  Hp times 42.41 gives you BTU per minute.  So 1 gpm at 1000 psi is equal to 24.74 btu per minute.  If you times that times 60 it gives you BTU per hour.  
 
Travis Johnson
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Christopher Shepherd wrote:Travis, I use PSI x gallons per minute divided by 1714 gives you hydraulic hp.  Hp times 42.41 gives you BTU per minute.  So 1 gpm at 1000 psi is equal to 24.74 btu per minute.  If you times that times 60 it gives you BTU per hour.  



Hey thanks for the engineering help! Using your figures it looks like my idea MIGHT work.

Assuming each drop of the plunger would displace a quarter of a gallon of oil, and the windmill dropped the plunger 60 times a minute, and the relief valve was set at 5000 psi, it would produce just over 100,000 btu's per hour.
 
Travis Johnson
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BUT...the original link might be the better design after all. It is proven, and quite simple. I really like it.
 
Christopher Shepherd
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Here is my proof of concept.  As you can see it is extremely complex!  It works good to tests load little engines too.  I still want to build one that is centripetal pump and heater at the same time.  It would be handy for heating our green house.
IMG_20190514_215941157.jpg
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IMG_20190514_215947148.jpg
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