tuna55
UltraDork
4/20/12 8:09 p.m.
Nice!
For reference, I work at a very large company which makes, amongst other things, large power generating natural gas turbines. This company is known to have very recently paid very little in taxes.
At any rate. Our highest temperature stuff is firing near 2500F. We cannot measure it there, because it is too friggin hot. Not sure if this helps, or how your turbine is supposed to compare, I am not a combustion guy. Exhaust temps tend to stay around 1000-1100, so if that's what you're measuring, you're darn close to some very large turbines in terms of combustion energy (per volume, of course). Not too bad, I'd say.
The temps I'm measuring are at the exit of the combustor just before where the turbine will bolt up. I've got no idea what the temps in the center of the combustor are, but I'm betting my thermocouple would die a spectacular death before I could get a reading. Everything I've read says that dumping gasses above 1100 degrees into the turbine will shorten its life considerably. I'm guessing that after the compressor is hooked up the possible temps will go up a good bit. We might find that out tomorrow.
Where did you find that EGT probe/display for $35? I can only find that particular display on ebay for ~$60.
In reply to 92CelicaHalfTrac:
http://www.ebay.com/itm/UNIVERSAL-PID-TEMPERATURE-CONTROL-CONTROLLER-/110557193685?pt=LH_DefaultDomain_0&hash=item19bdb8e5d5
It isn't sold as a EGT gauge. It's sold as a temp controller. and it was $38.99. Still the cheapest thing I could find.
Keep in mind, it's a 120V unit. Using it in a mobile application will require an inverter.
Ah ok!
Well either way, thanks for reminding me about that Auber stuff, i had completely forgotten about them and was planning on using them on the Smellica.
IT LIVES!!!
http://www.youtube.com/watch?v=aoELyuMKtuI&feature=g-upl&context=G2373125AUAAAAAAAAAA
Got the oil pump sorted this morning. It needs to turn about 10 RPMs or it overloads the bearings on the turbo. I rigged the rest of it together to test it. I couldn't run it more than about 2 minutes or everything started overheating. I also have no clue how fast the thing was turning. Now it's time to put it together for real as soon as the rest of the parts show up.
More to come.
Taiden
SuperDork
4/21/12 10:34 a.m.
Is it just the force of the expelled gasses that move the vehicle?
In reply to Taiden:
No. The force of the expelled gasses will be turning a free shaft turbine that will turn a transmission. This turbine is going to be a gas generator. It's going to turn about 100K RPMs. The free shaft turbine will only turn about 17K RPMs.
Here's another video. I cranked the fuel up on this one. Not to wide open, but probably half. Ear plugs are necessary at this point. The camera just can't reproduce the sound this thing makes.
http://www.youtube.com/watch?v=lZzZe2juk_Q&feature=g-upl&context=G2373125AUAAAAAAAAAA
I might have to build a scatter shield for this thing. It's making me a little nervous. It's absolutely screaming.
One interesting thing, at idle speeds the temps are in the 600 degree range. At half throttle they drop into the mid 400 degree range. I expected the opposite.
Time for another update. I've gotten a little done on the turbine this week. The oil pump is pretty much done and permanently installed in the frame.
Oil cooler and fan installed.
The control panel is slowly coming together as well.
More to come as it happens...
Ian F
UberDork
4/27/12 9:30 p.m.
Impressive. Insane, but impressive.
If I can make a suggestion, maybe add a ball valve to the fuel line so you can shut the fuel off in a hurry in case of emergency instead of twiddling knobs.
Otherwise, carry on...
Oh... And it sounds like you may come home one day to find the wife has hidden/sold your welder...
In reply to Ian F:
I'm probably going to run a normally closed solenoid valve with a great big red emergency stop button.
I did pick up a ball valve to put at the tank for a quick remote shut off. An uncontrollable fire isn't on the list of things to do anytime soon.
Scatter shield? Chicken. Reckon that thing would be LeMons legal?
OBTW: that fan looks real familar.
So, I got all the plumbing done on the oil system and tested it this afternoon. The pump won't prime running on 12 volts. I had to run it off my late speed control to get it primed. That's going to be a problem. The other problem is running on 12v it's putting out 120psi. It's overloading the turbo bearings so bad the shaft gets hard to turn. I'm going to have to rethink the pump arrangement and either go with a faster motor with a pressure bypass or a smaller pump.
I'll have to see what I can dig up.
Taiden
SuperDork
4/29/12 10:58 p.m.
what kind of pressure do you want at the bearing?
I'm thinking around 50psi would work.
Ian F
UberDork
4/30/12 7:29 a.m.
Could a fuel pressure regulator wouldn't work to bring the pressure down?
RossD
UltraDork
4/30/12 7:49 a.m.
RE Oil pressure: Add in something to drop the pressure. Use smaller diameter tubing, add more of the same diameter tubing, add an orifice, or a throttle valve,...
You must be a hit with your neighbors It even makes a little mini jet engine noise when the turbine spins up. That's so cool.
So, ignorant question, what's with the vacuum cleaner held onto the turbo inlet for a while? I noticed it sounds like the turbo spools after you take it away.
And in response to your EGTs going down after adding fuel, doesn't that happen in internal combustion engines, too? More fuel keeps it cool...
Twin_Cam wrote:
You must be a hit with your neighbors It even makes a little mini jet engine noise when the turbine spins up. That's so cool.
So, ignorant question, what's with the vacuum cleaner held onto the turbo inlet for a while? I noticed it sounds like the turbo spools after you take it away.
And in response to your EGTs going down after adding fuel, doesn't that happen in internal combustion engines, too? More fuel keeps it cool...
Vacuum cleaner is actually blowing into it in order to create an air charge to fire the combustor.
IIRC, the power steering pump should have a blowoff valve in it already. Maybe change the spring in it... or add an adjustment screw to that. Cheap, not hard to do except finding the correct spring calibration.
OR
Adjustable pressure relief valve with a gauge plumbed in upstream. Them's pricey.
OR
A rheostat/resistor to step down the motor RPM even more than it is, but that will generate a LOT of heat. I don't think a potentiometer will take that kind of abuse and live. For that matter, the motor might fry itself; as the voltage drops the amp draw goes up. That's how people fry starters when the battery is weak.
Ian, I thought of that, but I'm not sure if a fuel pressure regulator would handle a thicker fluid.
Ross, I bought a needle valve with the thought of using it to get a pressure drop, but I'm afraid it would then stall the motor driving the belt. I haven't tested that yet, but being a power steering pump, it's capable of pressures in the thousands. I think it's going to require some kind of bypass.
Twincam, luckily my neighbors are use to this stuff. The guy that lived here before me was just as bad if not worse. Something about rotaries with open headers. I wonder who that mad man could be.
The vacuum is just as Conquest said. It just gets the process started. Once the turbocharger spools up it takes over the air needs. I haven't quite perfected the start up procedure so my timing is off.
C, the pump is probably coming apart in the next day or so to see if I can adjust the internal pressure relief. The external ones are kind of pricy, but using one of them would let me bleed off the excess pressure after the oil cooler which wouldn't be a bad thing. I could dump that cooled oil back into the reservoir. I get the feeling heat is going to be a problem. I'm still thinking on that. I'm going to get by the hardware store to see if there is anything I can purpose, possibly a water heater pressure relief.
My only other thought is to build one. Probably not that hard, but time consuming. I'll keep looking for now.
Here's a question. If I put a T in the pressure line and plumbed the needle valve in a return to the reservoir would that allow me to regulate the pressure to the turbo with any consistency.