All electric....
Posted on 06/12/2009 8:36:49 AM PDT by janetjanet998
I have since checked out that site, it seems like impressive technology. It is strange they didn't mention that significant piece of information in the original piece.
The microturbines have been around for a long time and they work pretty well in stationary applications. I just have to wonder what the life of that mini-turbine will be in a vehicle. Perhaps they have some way to keep them in balance.
I have a Corvette. It only seats 2 unless some youngster wants to lie below the hatchback, but it goes 210 mph.
NASCAR fast.
Remarkably, it gets over 30 mpg at any speed over 75 mph that I’ve tried it at with the air conditioning running full blast.
It surely has to be more fun than any pius hybrid.
Not to mention the energy expense of the ‘main’ from which charging is accomplished. Energy ain’t free.
Okay, no automatic transmission.
But a turbine is a relatively simple machine compared to a reciprocating piston engine. Oil splashing around in a pan, and pumped to the top. A water jacket and radiator. Valves that require precise timing with expensive cams or more expensive computer controlled lifters. Precise fuel and air metering. Pistons and rings beating themselves to death at the end of a fly wheel. The whole thing threatening to stop working if one part fails. A real Rube Goldberg contraption that only works because of tinking by thousands of geniuses over 100 years.
How many machines do you need to make the parts for one turbine? Now think of how many different machines you need for every screw, nut, hose, shaft, gear, pump, spark plug, etc for an ICE.
In addition, a gasoline engine needs rebuild at about 3000 hours when ran at peak effiency and a diesel will need a rebuild at 10,000 hours. A turbine is good for what 50-100k hours?
I wish they would have shown what was under the hood. I am curious how they vent the exhaust. Even if it's just a micro-turbine, you would think the exhaust would be significantly hotter and under more pressure than a combustion engine.
General Dynamics did a lot of research and engineering on engine stability when it (and Chrysler) was engineering the M1. Perhaps some of those principles would apply to a much smaller turbine.
Probably higher pressure, but I doubt it is any hotter than an IC engine. You are burning a hydrocarbon fuel either way.
“Probably higher pressure, but I doubt it is any hotter than an IC engine. You are burning a hydrocarbon fuel either way.”
If it is engineered correctly, I would think the exhaust would be a little cooler, it is extracting more of the energy to do work and ejecting less as waste heat.
“My question would be is why do you need batteries?”
Because much fuel is spent getting a car started from a dead stop.
Anytime the engine is not needed to drive it charges batteries. Batteries get you started from a dead stop. THe engine only “drives” at higher speeds.
All electric....
Hmmmmmm. I'm not sure I agree with that. Turbines are simple in concept -- 'one' moving part --- but the tolerances and stresses that part experiences are extremely severe.
These micro turbines operate at something approaching 100,000 RPM. The 'one' moving part consists of a shaft with dozens of compressor blades that require perfect balance on one end, and dozens of other blades also in perfect balance in the combustion chamber on the other side where the temperatures reach 2000 degrees.
These aren't big hunks of steel like pistons. They are very thin castings of high tech alloys facing enormous stresses that will literally rip themselves apart with the smallest imperfection. Plus you have other parts such as igniters that face a harsh environment, fuel valves and filters, and some complex controls.
I wouldn't necessarily call them 'simple' machines.
As to 'overhaul' I'm not sure what the times are for these microturbines. For the most part, they are not designed for continuous operation. They are primarily designed for emergency back-up power applications so their total hours of service is relatively short. In a typical vehicle, they would be used every day for an hour or more with a great many 'heat-up / cool down' cycles.
All that said. I do like the concept of this vehicle. Let's just see how it does in the real world before we go crazy on it.
I presume this equipment is required to haul away Zero’s bullsh*t?
Actually it is for cleaning up after my Rotties.
In concept it is. In practice, it is not, as evidenced by the very much higher cost. It's practical operation is quite demanding, due to the high-temperatures and high speeds that the turbine works at.
The whole thing threatening to stop working if one part fails.You should see what happens when one part of a turbine fails!
Perhaps you can explain why a turbine engine is so expensive if it is so simple......
A turbine is a beautifully simple machine. Simple does not mean inferior or cheap.
“You should see what happens when one part of a turbine fails!”
A turbine is much more reliable because they are simple and have far fewer failure modes. Yes when they fail, they fail dramatically, but they are much less likely to fail.
“Perhaps you can explain why a turbine engine is so expensive if it is so simple......”
A turbine is more expensive for two reasons. They require more expensive material and they do not have the same economy of scale.
A functional turbine engine can be made by a fabricator for less money and less effort than a functional ICE engine because it is a more simple machine. I can send you to several sites that instruct metal fabricators on how to build their own functioning turbine using conventional materials, granted it will not perform like a GE engine but show me someone that can build a 4 cycle engine in their shop out of stock material.
Don't take offense when I call a turbine a simple machine. Simplicity is a complement from an engineering standpoint. Also, is a turbine more expensive per HP or kilowatt generated? I'm not sure that they are really that much more expensive based on output.
LOL
I only have maybe 40 more years to live.
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