In 1963 Chrysler was on it’s way to producincing a turbine powered car.
What might have happened had they gone on and produced the car? Would the oil crisis not have happened?
Why do you think the technology was not followed up on?
Should it have been?
It seems to me it would solve a lot of our fuel and pollution problems we have now.
I’m confused. First, why would you think that a turbine car is somehow energy efficient? Turbines suck fuel at a prodigious rate. Sure, they can burn other fuels than gasoline, but those fuels still have to be drilled for/manufactured. And since we use petroleum as our primary energy source, you’re still going to burn it up. So it’s not environmentally friendly.
Second, the emissions from a gas turbine are pretty impressive. It would take a ton of engineering (and probably the introduction of a whole bunch of additional inefficiencies) to get that under control.
Third, a turbine spins FAST. That has many problems in a car. First, what happens in an accident? Aircraft have thrown turbine blades right through the engine cowling and through the fuselage of the aircraft. So you’re going to need some heavy shielding around the turbine, and god knows what will happen in an accident.
Fourth, a turbine is HOT. As in, thousands of degrees. Again, in an accident you’re looking at an awful lot of fuel and hot metal mixed together. Not a good thing.
Then there are the durability issues - a large rotating mass has a lot of force on its bearings when you turn a car. Airplanes don’t turn that much, and don’t get jostled around by potholes and pavement cracks. It would be interesting to see how long a turbine would really survive in day-to-day driving. Plus, there’s the FOD problem - you can’t pick up debris on the road and let it into the engine. And yet, turbines suck in huge volumes of air. So you’d need some really, really good filtering, and it would have to be maintained very well.
I wonder if the gyroscopic forces from the spinning turbine would make the car squirrely?
Finally, there’s the cost issue. Turbines require very high precision machining, and use exotic materials. They aren’t cheap. You can buy used Learjets with worn out engines for almost nothing, because new engines are worth more than the airplane. It’d be quite a trick to get turbine costs down to the point where they are competitive with IC engines.
And what kind of transmission do they have? How do you get power to the wheels? What about spool-up and spool-down times? How responsive is a turbine car?
There are many, many good reasons why turbines never saw the light of day in cars.
Good post.
Here’s my contribution: They’re noisy, too.
I assume you meant “reciprocating” instead of IC (Internal Combustion). Gas turbines are internal combustion engines.
I’d like to say that a turbine car is feasible and competitive with other IC engines (spark ignition and diesel piston engines, Wankel rotaries) using the current level of technology.
If an auto manufacturer was willing to invest in the tooling and the infrastructure,
a turbo-electric hybrid is feasable.
Chrysler already had thermal recycling and variable geometry, I say we also use high temperature, low inertia ceramics for the turbine and combustion chamber. Adding a alternator/motor to the gassifier turboshaft would augment the variable geometry vanes to eliminate turbo-lag…the main drawback of the Chrysler Turbine. Along with preheating the incoming charge of air, we could also preheat the fuel. Bolting a scaled-up alternator to a multi-stage power turbine would charge a pack of batteries/capacitors/magnetic flywheels, which in turn would power motor/alternators in the hubs of all four wheels, which in turn would recover the car’s kinetic energy during braking.
Sam Stone wrote how high speed turbine blades can perforate stuff and also about gyroscopic forces, but weve had turbocharged engines for years without those problems.
Since they’re already masters of both gas turbine and electric motor technologies, I’d say General Electric is in the best position to enter into a joint venture with an auto manufacturer to provide the hybrid drivetrain.
Suspicious
You just made all that up, didn’t you? 
Turbine-electric might work. It certainly gets rid of the transmission and response-time issues. But how is that more efficient/better than, say, diesel electric?
In a hybrid, you gain quite an advantage from starting and stopping the engine and only running it when you have to. How easy/efficient is it going to be to do that with a turbine?
NASA has been doing research on a low-cost turbine for general aviation, but in this case ‘low cost’ means under $100,000. I don’t think we’re going to see car-sized turbines for $1,000. That’s going to make it hard for them to compete against existing motors.
This reminded me of Mazda’s rotary engine. Neat link.
Noooooo…
Using the alternator in motor-mode would spin up the turboshaft to speed faster than the turbine would all by itself.
It was a joke. I do not understand engine mechanics, so you might as well have been saying, “If we were to refrobulate the gargleschmazzer on the variable-frequency dynamic modula-TOR, then we might expect an increased viscosity on the post-helical subprocessor platform.”
That’s such an elegant little gadget.
[momentary hijack]
I note that the three rotor corners are always in contact with the stator walls, right? What system of lubrication can they possibly use to keep those corners from wearing out quickly and shooting the engine’s efficiency all to hell because of gas leaks?
I disagree.
Very, very, expensive. Of course, the more you produce, the cheaper they get.
By your use of “gassifier”, I would assume that you are talking about a free power turbine. Adding a motor to the gas generator section would not do a whole lot for lag, since there is no direct connection between the power turbine and the gas generator. Even assuming you could eliminate any lag in the gas generator section, you would still have to wait for the free power turbine to spool up. Did you mean you would add the motor to the power turbine itself, or did you not mean a free power turbine design at all?
Why would you want to?
If you are going to drive the car using motors at each wheel, why even worry about the lag at all?
Sam Stone seemed to be speaking of a modern axial flow turboshaft engine. A turbocharged car uses a centrifugal compressor with a radial inflow turbine. You can’t really compare the two.
I guess I just don’t see how all that mess would be in any way better than a modern 4 banger with a 5 speed.
IANA mechanic, but the tubine engine does sound inappropriate for cars, for the reasons others have stated.
Isn’t it all a bit irrelevant anyway? Won’t fuel cells pretty be in pretty much all cars within the next 20 years?
In Thermodynamics class, we were studying various types of engines. The professor showed us a drawing of a gas turbine engine BMW had developed in the early 90s to use in their cars (it never went into production). The design used a radial-flow compressor and turbine, and had heat recovery by means of a slowly-rotating porous ceramic disc that was warmed in the exhaust stream, then carried the heat to the intake stream.
The prof said the main motivation for turbines was efficiency. The thermodynamic efficiency (energy produced for fuel used) of gas turbines can be on the order of 50%, while most gasoline-piston car engines are on the mid-to-upper twenties. (Diesels range from modestly better than that, for small automotive engines, to the mid-forties for large railway or marine engines).
As presented by the prof, this engine would have turned really fast, been significantly more efficient than the gasoline or diesel engines currently in use, and somewhat versatile in the fuel it could use. It also would have been expensive, at least at first. As well, every mechanic in the country knows piston engines, but very few have expertise on turbines, so maintenance might be pricey.
It never took off, as a result. Also, there might have been some issues with designing a transmission to step the speed down to the degree required.
So says the prof, anyway.
Addressing a few points of Sam’s
From what I’ve been taught at engineering school, engines can generally be ranked on thermodynamic efficiency (energy out over energy in) from best to worst as follows:
Gas Turbine (up to 50% with heat recovery and high compression ratios, etc)
Large Diesel piston (The biggest can be in the upper thirties and mid forties)
Small Diesel piston (Automotive types are generally in the low thirties or so)
Automotive gasoline piston. (Mid-to-high twenties, these days)
I dunno, but are we sure a small GT would be worse than a piston engine? Is it anything a catalytic converter can’t handle?
As mentioned above, there’s no need for turbine blades at all. You can make a radial-flow turbine. The design is pretty simple, just a pair of disc-type things with little ridges on them mounted on a shaft. Remember, the point of an airplane turboshaft engine is to shoot a lot of air backwards fast. With a car engine, we don’t want to produce fluid-dynamic thrust, we want to generate shaft power alone.
I don’t think it’s really so bad. Since there’s no blades to go flying around, the hot metal should be pretty well confined to the engine.
Sure, but we don’t want a large rotating mass. We’d want a light turbine. One that weighed not a whole lot more than the one in a turbocharger, or the crankshaft in a car.
Sure they do. Every takeoff is a turn, every landing - just in the vertical plane. Maybe they fly in straight lines more, and cars drive on curvy roads, but planes turn all the time. And fighter jets are designed to turn a lot. And they do all this with much heavier turbines than you’d ever need in a car. The bearings exist, though they’d be more expensive than the ones for your crankshaft.
Carrier-based fighters in rough weather. Turbine-powered helicopters landing on frigates in the North Atlantic. Turbines can be pretty robust. All day, every day? If the turbine is built the way I’d expect (similar in weight to a gasoline-piston engine, or lighter), rough roads shouldn’t pose a problem much more than to piston engines.
We’re not talking the GE90, we’re talking an oversized turbocharger. We can keep air from getting into our gasoline engines today, and unless this turbine sucks way more air, we shouldn’t have any problems.
Not if it’s mounted in the right place, and the shaft is relatively low-mass.
Not sure what to say here, exept that one of my co-workers, an ex fighter instructor, told me this weekend that the response time on aircraft turbines today is a lot better than 30 years ago. I don’t know why, though, so I’d like to find out the details.
I still have my model of the Chrysler Turbine Car that I won at the Chrysler Pavilion at the 1964-65 World’s Fair. A pretty neat car, I thought, and for years afterwards wondered why I never saw one. I suspect that the hufge amount of support and retooling was the big thing keeping it off the roads (I’ve seen other projects, since, that were ready to roll, scuttled for that reason). The Oil Crisis in the early 1970s probably killed it off.
as for the Wankle Rotary Engine, my understanding was that the biggest headache when it was first introduced was leaking seals – you require the seals separating the three chambers to put up with an awful lot. I’ve sort of assumed that it was new engineering materials that have helped it make a recent comeback, but that this is still an issue.
Volkswagen had a working turbine car sometime early 90’s. Radial turbine with heat exchange[1]. The turbine was made out of ceramics and relatively small - about twice the size of a PalmPilot (since that’s the only object I see around my desk that I can use as comparison). It was NOT noisy.
These turbines are not like aircraft turbines anyways: Point of a/c turbine: accelerate as much air as you can to maximize (mass of air)*(velocity of air) that comes out at the other end. [2] The point of an engine in a car is more like that for a stationary gas turbine: maximize the moment on the shaft. Any speed or pressure the air has when leaving the turbine that is not needed to overcome the losses in the exhaust system would be waste.
Any directly-driven turbine car has one big disadvantage: reaction time.
Gas engine: You push the accelerator. engine revs up. car accelerates.
Turbine: You push the accelerator. Nothing happens. You get nervous. Still nothing happens. After what seems like an eternity (but is only 1-2 seconds or so), the car finally accelerates.
I like the turbine/electric use. A small gear to bring the rpm down (not a big deal, but some engineering required), a generator that can be used as starter, a battery, and an electric motor (or one per wheel). The turbine could run at a constant rpm, very efficient (much more efficient than a diesel or gas piston engine), and Bob’s your uncle.
The problem, of course, is the weight and lifetime of the battery. These thingies are heavy and tend to die (I heard the battery in the Prius has a lifetime of 6-8 years, not sure whether that’s true).
Bottom line: makes complete sense from a thermodynamic point of view, tricky in practice
dorfl
[1]The air that leaves the turbine is used to heat up the air that comes in, which fosters a higher temperature for buring the fuel, which makes for much cleaner and more efficient combustion.
[2] for the techies: a/c turbines nowadays also have to focus more on moment on the shaft since they are basically driving a big fan (the thingy you see when you look in the engine from the front). Most of the air that the turbine accelerates does actually NOT go through the turbine any more, but is accelerated by the fan and bypasses the core. Therefore, the point of the turbine is mostly to drive the shaft that drives the fan that pushes the air back. (You still see some engines on old 737’s that have a very small diameter. these are old and very inefficient.)
Actually, variable pitch turbine blades are used in turbochargers now. Nasa has also developed an air bearing for turbocharger applications. Pretty cool stuff if it would ever hit the car market.
Sam pretty much nailed it. There is a place for turbine engines but not in cars. Jets use them for reliability and speed. Period. They are not fuel efficient and cannot be made to burn as cleanly as a positive desplacement motor.
What I meant by “gassifier turbine” is what you mean as the “free turbine”, the part that actually builds the boost.
The whole concept of thermal recycling is to make the engine more efficient by recovering heat otherwise lost in the exhaust. The Chrysler Turbine preheated the incoming charge of air by passing it over recuperators…metal or ceramic monoliths rotating in and out of the exhaust stream on a continual basis…and recovers over 1000 deg. free thermal energy. Preheating the fuel a few hundred degrees would recover a little more of that energy.
Point conceded. Electric motors drawing off storage cells would not need a generator with instant response. However, a turbine with a direct mechanical connection to the drive wheels would.
Wolftsu: I was pretty much limiting my comments to the turbine cars I’ve seen in the past, which basically used aircraft turbines. General Motors had one, I believe. I saw a turbine Corvette once, too.
Hmm. I’ve never seen such a thing. Mind you, if you strap a turbofan to a Cavalier, you get a lot of the problems you raised in your post: massive fuel consumption, foreign object damage, inertial-gyroscopic effects, etc.