Author Topic: Concept for twin flame licker..  (Read 6861 times)

Offline John Hill

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Concept for twin flame licker..
« on: September 15, 2010, 05:49:12 PM »


A twin flame licker using an inspiration from the Jan Ridder piston valve method.

As the engine turns one piston coming up pushes its valve piston up which via the linkage pushes the other piston down.

The two cylinders use the same flame and I expect that the exhaust from one cylinder will blow the flame towards the port of the other cylinder, I do not know if this is an advantage or not. :scratch:

If it work, 100% increase in fuel economy! :ddb:  (If it works).
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Offline Bogstandard

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Re: Concept for twin flame licker..
« Reply #1 on: September 15, 2010, 07:09:09 PM »
John,

I experimented with two cylinders very similar to what you have suggested. Despite trying flames every which way, it was a total failure, the 'puff' from each cylinder just deformed the flames too much to continue running.
It was fine with two flames on the outside. I eventually went for the 'boxer' type configuration.

The flame shapes are critical with this type of engine, and a tiny bit out of position will stop the engine running.

This is the post I did it all on.

http://www.homemodelenginemachinist.com/index.php?topic=212.0


John
If you don't try it, you will never know if you can do it.

Location - Crewe, Cheshire

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Offline John Hill

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Re: Concept for twin flame licker..
« Reply #2 on: September 15, 2010, 07:14:05 PM »
Thanks John,  flames on the outside then! :beer:
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Offline John Hill

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Re: Concept for twin flame licker..
« Reply #3 on: September 15, 2010, 08:04:14 PM »
I was sitting here dozing in front of TV and I began thinking that if I put an exhaust valve (maybe a ball in a seat on top of the cylinder) there would be much less puff out the other port. :scratch:
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Offline NickG

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Re: Concept for twin flame licker..
« Reply #4 on: September 16, 2010, 09:23:36 AM »
I can't see the pic but wouldn't the air just take the easiest route and go out of the port rather than open the ball valve though?

Nick
Location: County Durham (North East England)

Offline John Hill

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Re: Concept for twin flame licker..
« Reply #5 on: September 16, 2010, 05:37:06 PM »
I can't see the pic but wouldn't the air just take the easiest route and go out of the port rather than open the ball valve though?

Nick

In this type of valve the piston coming up compresses the air slightly which moves the valve piston and so opens the valve, the trick would be to have an exhaust valve that opened at less pressure than it takes to move the valve piston. :scratch:
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Offline Bogstandard

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Re: Concept for twin flame licker..
« Reply #6 on: September 16, 2010, 06:18:03 PM »
John,

I don't think you realise how fickle and low powered these types of engines are, just farting near them will stop some of them dead.

Jan does do plans like your original concept of the swing bar at the back, but like I said with mine, he uses two burners on the outside as well.

http://heetgasmodelbouw.ridders.nu/Webpaginas/pagina_happer_inw_schuif_2cilinder/inw_schuif_frameset.htm


John
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Offline John Hill

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Re: Concept for twin flame licker..
« Reply #7 on: September 17, 2010, 12:34:09 AM »
John,

I don't think you realise how fickle and low powered these types of engines are, just farting near them will stop some of them dead.

Jan does do plans like your original concept of the swing bar at the back, but like I said with mine, he uses two burners on the outside as well.

http://heetgasmodelbouw.ridders.nu/Webpaginas/pagina_happer_inw_schuif_2cilinder/inw_schuif_frameset.htm


John

Frankly John I am suprised that any can run at all and some run really fast! :scratch:

I have had enough comments to make me think maybe I should leave these well enough alone, but then on the other hand! :med:

My biggest challenge at this time is still working to very small sizes but if I try to make a bigger one I will need a Primus or small nuclear reactor to make it run.... :beer:
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Offline NickG

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Re: Concept for twin flame licker..
« Reply #8 on: September 17, 2010, 03:48:18 AM »
John,

Having built one of these also I have to agree with Bogs - this particular design is extremely fickle! Not wishing to put you off, I think it's a good idea and I have seen some flame lickers which have such a valve to release pressure as the piston nears TDC, but those were engines that had the valve driven by a cam.

In this one, as you rightly say it's opened partially by pressure on this one but that pressure is a tiny tiny pressure, due to the necessary low friction of the system it opens as soon as the pressure rises above atmospheric - remember there is no spring holding the valve shut, and there can't be one otherwise it won't be open long enough to draw in the hot gas.

I ran mine again the other day for the first time in ages and every time I am surprised how critical flame position and steadiness is. To give you an idea, 1mm in flame position can mean the difference between doing a few hundred RPM and not running at all, somebody moving in the room or opening a door can disturb the flame enough to stop the engine - they are a nightmare to get running but a joy to watch once they are!

Nick
Location: County Durham (North East England)

Offline Bogstandard

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Re: Concept for twin flame licker..
« Reply #9 on: September 17, 2010, 04:58:34 AM »
John,

I have seen larger versions of these engines made, about the same size as a small compressor pump (and vertical), about 12" high, and they seem less prone to the variations encountered with the smaller ones, as the wick was in like a long groove sitting directly under the horizontal inlet. Jan also does a vertical one that I think might take well to scaling up. If you don't want to go thru Jan, I have a copy of his free plans.

Even the commercial ones had very little power, a big engine to drive one sewing machine. So they were lost as prime candidates as a power source very early on.


John
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Location - Crewe, Cheshire

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Offline John Hill

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Re: Concept for twin flame licker..
« Reply #10 on: September 18, 2010, 02:51:28 AM »
I am sitting in front of TV slowly filling a small notebook with doodles on how to attack the challenges of this type of engine,  one day maybe... :coffee:

Meanwhile, I really should be culling the stock in the garage(s) prior to getting this house ready for sale. ::)
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