Turbine engines


#1

In the 50’s and 60’s there was some interest with car manufacturers to experiment with turbine engines. They soon dropped them as there were acceleration problems. Hybrid cars that use electric motors as the main motive power have an engine back up. Wouldn’t it make sense to install a small turbine to keep the battery charged? could the turbine be computer controlled to burn a variety of fuels?


#2

Good point, turbines are very compact, but not very efficient. The big problem was fuel economy, and Chryler had to put a bulky heat recovery unit on theirs, and it still was not very good. There were also acceleration (lag) problems, as you mention.

The reason for hybrids is to increase overall fuel economy, and using a turbine would defeat that purpose.

Large industrial turbines use very large heat recovery units to capture a good deal of the heat left in the exhaust, and turn that into steam to drive an additonal electric generator. Such plants are called Combined Cycle plants.


#3

They inhale vast quantities of fuel and air. The advantage is, they burn anything.
My push is for a cheap, reliable generation motor like a Briggs and Stratton, or Honda 4 stroke with a carb; like the motors used on generators but made flex fuel ready to burn gasoline, gas or alcohol based fuel, whatever any free enterprising farmer wants to put out on the side of the road. When run in a very narrow power range, they are very efficient. My Generator can supply electricity for my entire house with as little as a gallon of fuel an hour.


#4

Turbines do indeed have a “drinking problem”, i.e.–they are not economical, relative to their power output. If a hybrid is designed to conserve resources, a small diesel engine would be a wiser choice than a turbine.

Also, turbines put out a very large amount of CO2. This would also be looked upon as a step backward by environmentalists.


#5

Transport category airplanes have turbine engines because Turbines like really, really cold and dry air that’s found at 25,000 feet on up. The only practical car use of a turbine is found inside of a turbocharger. Around sea level a turbine engine uses too much fuel to really be efficient.


#6

They simply waste too much heat…When you buy fuel, you are buying BTU’s…


#7

Turbines do ok efficiency wise when they run at full power. Jet transport and Abram tanks run close to that while cruising. Chrysler’s turbine car did not let its engine run at full power all the time. But in a hybrid, the computer can start it up and run it at full power when the car needs juice then shut it off. By doing this, the turbine would run at its most efficient range.

Turbine may be no more efficient than a regular 4 stroke piston engine at full power, but it is a lot smaller and lighter. This means the front end that wraps around the engine can be smaller. You won’t need huge brakes, especially when you have regenerative braking, to scrub off the momentum of a heavy piston engine, which means the wheel that does around the brakes and in turn the wheel well, fender, etc. can be smaller. A smaller structure up front weigh less, reducing power requirement. All these aspect allows a more aerodynamic design, unlike the boat that Chrysler made.

However, I think the problem with turbine is cheaply creating the right material that can withstand 2000F, a temperature commonly seen in jet engines, and the rotation induced stresses. If you recall flight UA 232, a metallic flaw in a jet engine no greater than a grain of sand brought down a 200ton airliner.


#8

Turbine engines are great for jets, but not for cars due to:

  1. No low-end torque
  2. High fuel consumption
  3. High emissions
  4. Difficult to get power from the turbine to the wheels
  5. Not efficient at less than optimal revs
  6. Dangerously hot exhaust gasses
  7. Expensive to service (not your shade-tree mechanic)
  8. Expensive to manufacturer

These are just a few, I’m sure there are more.
Twotone


#9
  1. That’s what the electric motor is for.
  2. Not at their optimal speed.
  3. Dunno if there’s anything to be done about that. Probably cats.
  4. That’s what the electric motor is for.
  5. That’s what the electric motor is for.
  6. ICEs have dangerously hot exhaust gases.
  7. If they were more common, they wouldn’t be.
  8. We aren’t talking about a jet engine here, and if they were more common, they wouldn’t be.

That’s one, maybe zero, but I’m sure there is a legitimate objection somewhere.


#10

the one advantage of putting a turbine to power a battery for power and then to the wheels, is that they use the same amount of fuel at idle as they do full tilt. good or bad, they do.

Union Pacific had turbine trains in the 60’s. the made 8000 HP, but the train itself was 3-cars long.


#11

Would the speed of blades make a break down dangerous to a passerby and would it be possible to run them in very dusty or hash environments without attended wear problems that only the US military’s deep pockets could deal with ? The first time you had to replace one of these babies, a good old Tecumseh would look awfully good. Why bother ?
That’s why diesels aren’t taking over the task. Gas engines and gasoline are cheaper solutions for the time being. Why bother til the bean counters give us the go ?


#12

Nope, they use much more fuel at full throttle, that’s what ‘full throttle’ means. The thrust generated by a jet engine is directly proportional to the amount of fuel being burned.


#13

texases is right; turbines need a huge amount of EXCESS AIR(like 300%) or so and all that air has to be heated by the fuel. In a jet engine and turbo prop that hot air is used for thrust to push the aircraft. This could theoretically be done with a car, but a thrust of very hot air in traffic does not make sense.

In large stationary power plants, simple gas turbines with no heat recovery are only used for “peaking” to supply elecricity for the peak loads. For steady “base load” these turbines alway have secondary heat recovery to generate additional power (combined cycle)or use the heat for the plant process (co-generation).

In other words, you will not any time soon see a small gas turbine in hybrid car. In the early 1990s under the PNGV program 5 manufacturers produced 80 mpg mid size cars. All used small diesels running at optimal speed to charge up the batteries. Cost was no object here and carbon fibre bodies and other exotic materials were used.


#14

The guy that started Compaq computers built a Saturn with a small turbine engine inside a small alternator, the whole thing being about the size of a 3 lb coffee can. For storage, he chose a high speed gyroscope. The whole thing got 100 mpg.

It seems like a good idea until someone gets in an accident and a mass of steel spinning at 60,000 rpm gets uncaged, I wouldn’t want to be in the path of that. He didn’t have rechargeable lithium-ion batteries at the time.

With todays battery technology, I think this should get another look, it might be feasible. It might be that the engine might simply cost too much.


#15

“The guy that started Compaq computers built a Saturn with a small turbine engine inside a small alternator, the whole thing being about the size of a 3 lb coffee can. For storage, he chose a high speed gyroscope. The whole thing got 100 mpg.”

Source please…This sounds like Urban Legend stuff…


#16

Caddyman, the poster problably meant a flywheel rather than a gyroscope. It’s theoretically possible to use a flywheel as an energy storage device, but it’s less effective than a good battery and does not solve any of the problems, it just demonstrates that it can be done.

A very large spinning flywheel would make it difficult to rapidly change direction because of the very large inertia.

You can run a gas turbine on peanut oil, but what does that prove?