My Kart

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Vaulter
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My Kart

Post by Vaulter » Mon Dec 20, 2004 7:19 pm

So I finally got my Lockwood to run on liquid propane. I ended up changing my fuel rail and some demensioning on the engine itself. Below is an early picture of the kart with the engine mounted. The brakes are not yet finished and my jet only has on and off so test drives have been limmited. I got up to about 10 mph, killed the jet, and put on the Fred Flinstone brakes.

Does any one have a suggestion on intake bevel. I origionally made a flare to go from 4 to 5 inches diameter in 5 inches of length. Would this help my jet throttle. Thanks everyone.
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jmhdx
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Re: My Kart

Post by jmhdx » Tue Dec 21, 2004 9:57 pm

Your engines geometry looks a little under optimized. The combustion chamber seems large for the exhaust and intake pipe diameters, shortening it by a couple of inches might help.
This is possibly the most optimised lockwood, try to copy it's geometry.
[img]C:\My%20Documents\pulse\bg37.jpg[/img]
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larry cottrill
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Re: My Kart

Post by larry cottrill » Tue Dec 21, 2004 11:53 pm

Mike -

The distribution of radiation temperature in that engine is astonishing. I'll bet somebody could write their Master's thesis doing a thorough analysis of the combustion energy in that machine.

That must be a pretty big one, the way it's proportioned. Notice how little the difference is between the intake and exhaust nozzle areas, unlike most of the smaller examples you see running.

Man, a LOT of the combustion is taking place in that pipe!

L Cottrill

Bruno Ogorelec
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Re: My Kart

Post by Bruno Ogorelec » Wed Dec 22, 2004 4:27 pm

Larry Cottrill wrote:The distribution of radiation temperature in that engine is astonishing. I'll bet somebody could write their Master's thesis doing a thorough analysis of the combustion energy in that machine.
<sinip> Man, a LOT of the combustion is taking place in that pipe!
Once you have some idea of what is happening inside, it's nice to verify that on such a clear picture. Let me venture what I think is happening.

The intake and exhaust ends are obvious -- cool because of the two-way flow, suck and blow.

The middle of the chamber is cool because the fresh mixture cools it as it fans out, in billowing turbulence.

The shoulders of the intake are hotter than the middle of teh chamber because they are pockets of stagnant hot gas, not much disturbed either on intake or on exhaust.

From the middle of the chamber downstream, it gets increasingly hot because not only is combustion going on all the way to the end of the engine, as Tharratt teaches us, but expansion transfers heat to the walls. The greater the gas speed, the greater the heat transfer -- until about halfway down the tailpipe.

From that point on, the influence of sucked-back cool air is increasingly evident.

So, I'd say this shows fresh air penetrating perhaps halfway into the tailpipe. Maybe even further, but beyond the halfway point it obviously gets almost as hot at the exhaust gas.

Bill (Hinote), what does that tell us about your four-piper? Let's rethink its heat pattern. Man, maybe it shows us a perfect combustion pattern, rather than what we all assumed -- combustion mostly in the tailpipe!!!

Look, due to the unusually short chamber, the four-pipe layout and the evaporation of liquid fuel, your chamber is probably cooled rather better than in the common or garden Lockwood. The walls are bathed more intensely in the cooling fresh charge. That's the reason it's dark! If you measured internal temperatures along the engine axis, I bet you'd get a completely different heat pattern from the situation you get along the engine wall.

Bill, you may have written off that horned beast too easily.

Larry, thanks for the inspiration. Now I owe you a beer, not just money.
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Mike Everman
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Re: My Kart

Post by Mike Everman » Wed Dec 22, 2004 6:56 pm

Here's another photo of the Lockweed.
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mk
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Re: My Kart

Post by mk » Wed Dec 22, 2004 7:18 pm

There's nothing to say about the second picture.
Self-explaining in the details.

These two pitures where the first I found on the net about a year and some months ago...

...The cha-haa-ange, the cha-hange, the cha-a-ange, the cha-ha-ha-ange...

...nuff said.
mk

Anthony
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Re: My Kart

Post by Anthony » Thu Dec 23, 2004 10:41 pm

Mike Everman wrote:Here's another photo of the Lockweed.
Yeah, look at this guy in the background, he just learned pulsejets are LOUD!
Anthony
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