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DumHed
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Joined: 29 Jun 2004
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Location: Sydney


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Well, the engine's a bit more together now, and has the new turbo on it.

I had to replace the whipper snipper engine with a 300w scooter motor to get the oil pump working, but it now makes plenty of oil pressure even at 12v.

Last night I got it running properly, and it sustains 15psi of boost with the lpg valve wide open.
I need to look at liquid fuel, or at least a way to prevent the lpg cylinder from icing up to get more power out of it.

The next step is to put a thrust nozzle and an intake bellmouth on it and measure the thrust (if any Smile)

Once I have it working in thrust mode I'll be putting together a freepower turbine setup and hopefully driving something with it.

Here are some pics:




The oil cooler / tank is a small Nissan intercooler with some plates over the normal inlet and outlet and the usual pipe fittings.
I need to add a cooling fan to it as it heated up quite fast!
Oil pressure is regulated by a Malpassi fuel pressure regulator, which ramps up the oil pressure as the boost rises.
The oil filter mount came from a Nissan SR20 engine, and I made a custom backing plate with the pushlock and compression fittings in it. There are o-ring seals between the filter mount and the plate.



The turbo is from a recent model Nissan patrol turbo diesel.
It's quite small (40mm inducer and turbine exducer), but has a variable vane turbine housing and a 9 blade high flowing turbine wheel.



The ignition system is a 555 timer based coil driver as used in a Jacobs ladder display.



The oil pump is now driven by a 300w 24v scooter motor with a custom alloy pulley and a timing belt tensioner from a Nissan CA18 engine. At 12v the pump spins at about 600rpm, which is enough to maintain 60+psi of oil pressure.
If I end up needing more flow I can run the motor at the full 24v

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Post Tue Dec 13, 2005 11:02 pm 
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prong
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Joined: 19 Jun 2004
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hehe looking good, if only you put that much effort into your half built robot!

Post Tue Dec 13, 2005 11:08 pm 
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Spockie-Tech
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Joined: 31 May 2004
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Location: Melbourne, Australia


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Thats a nice bit of engineering.. Cool

I'll be interested to see if you can get any useable amount of power out of it.. most of the car turbo powered rigs I've seen like that are mainly good for making noise and heat.

It usually seems to turn out to be far more efficient to feed the LPG to a piston engine and get a useable rpm out of it, than to try and gear down a 50,000rpm turbine or extract any thrust from the low energy turbine exhaust. (At least according to some web pages I've read on them, not my own experience)

Undoubtably cooler and more wow factor than a 3.5hp briggs and stratton popping away though. Wink
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Post Tue Dec 13, 2005 11:38 pm 
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Rotwang
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Joined: 15 Jun 2004
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Location: Vic


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Very impressive, as far as LPG a simple vaporiser heated by oil will stop problem with bottle getting cold and gas pressure dropping. Tip bottle up side down so liquid is withdrawn then run through copper tube in oil tank or similar, regulate fuel with a tap on liquid line at heat exchange.
Or use an old impco converter and plum the oil where the water use to connect , modify by removing the low pressure valve and regulate flow with tap on liquid line in. Smile

Post Wed Dec 14, 2005 5:15 am 
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Knightrous
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When does the afterburner go on Andrew? I love the rig, it's like Mark Nye's work, but involves a lot more Nissan parts Very Happy
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Post Wed Dec 14, 2005 8:42 am 
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DumHed
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hmm that'd work really well actually!

The turbo also has a water cooling jacket that's not used at the moment, so I could quite easily use that for vapourising kerosene or other liquid fuels.
I'll be making up some different injector setups for it to try different fuels anyway.

As for power, it's certainly most efficient at making heat and noise, but apparently it is possible to extract decent shaft hp.
There's a guy in NSW with a turbo turbine powered motorbike that's making over 100hp at the rear wheel, and he's also done a go kart which has the normal go kart chain drive directly from the power turbine shaft. Since peak power is at something like 32000rpm it has a pretty high top speed!!

The usable power output seems to work out to about 1hp for every pound of thrust the engine makes in pure jet form.
I think it would be reasonable to expect to make 15-20lbs of thrust out of my engine with the right nozzle, and it seems pretty well suited to the large power turbine I have Smile
If it works I'll be putting it in a small boat I have, driving a waterjet unit from a jetski.

This project will have to take second priority for a little bit though, while I work on my car, and then robot so I have something to take to robowars Smile


quote:
When does the afterburner go on Andrew?


If I do the power turbine setup it won't have an afterburner, but otherwise it'll get one for sure Smile
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Post Wed Dec 14, 2005 8:44 am 
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DumHed
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Joined: 29 Jun 2004
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Yesterday I put an intake bellmouth and a jet nozzle on it, and it spooled up 25psi for about 5 seconds and then boost just dropped and it stopped running.
On closer inspection all the tubine blades are about half their normal length so I think it's either over revved or over heated!
Previous runs didn't seem to get too hot, but the nozzle would have changed things a bit.
Fortunately I have a couple of spare turbos Smile

I'll try a Mitsubishi TC06 on it next, as it has a much larger turbine.
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Post Thu Dec 15, 2005 3:11 pm 
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Knightrous
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Awesome! Get some videos happening Andrew. We want to see the action as it happens! Laughing
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Post Thu Dec 15, 2005 3:44 pm 
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DumHed
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yeah I was hoping it'd run a bit longer so I could have done some video Smile

Need a higher flowing turbine housing? Just chuck it on the lathe Smile




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Post Thu Dec 15, 2005 4:59 pm 
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Big AL
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Joined: 16 Oct 2004
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LMFAO Laughing
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best quote ever:: "Those Gas-Turbine style warehouse heaters arent illegal, and neither is remote controlling one as far as I know."

Post Fri Dec 16, 2005 11:22 am 
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Totaly_Recycled
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The turbine was awsome when tested after the robo wars event it wasnt as noisy as i expected it to be though ..it would have been great if we had a few marshmalows to toast Laughing

Post Thu Jan 19, 2006 2:34 pm 
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Spockie-Tech
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http://www.rcdon.com/html/experimental_projects.html

Shocked Shocked

This guy has too much time on his hands !
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Post Tue May 08, 2007 10:21 pm 
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Knightrous
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Last Post: Thu Jan 19, 2006 2:34 pm

Necromancer Laughing
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Post Tue May 08, 2007 10:25 pm 
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Spockie-Tech
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Just trying to keep in relevant to previous turbine builds by dumhed etc. Razz

check out the Turbotug on that page ! Jet Turbine Nar Karts anyone ? That thing is incredible. look at the dashboard detail and ECU and stuff he built for it. It must have thousands of hours worth of time/$ in it.
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Post Tue May 08, 2007 10:36 pm 
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DumHed
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Joined: 29 Jun 2004
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yeah that guy has done some nice stuff!!

I'll have to finish off my turbine engine one day Smile
There's been too much racing, working, and house moving going on!
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Post Mon May 14, 2007 11:05 am 
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