williamweaver, Diesel Electric Locomotives are similar to hybrid cars except for one thing, the battery. This is changing, of course. Even though they are very efficient, making them more efficient is worthwhile, considering how much they are used. Actually, GE is taking the next step and putitng in batteries. These can be charged during operations and can recover energy while braking. They then provide low speed power which is more responsive than the diesel gen set.
As for turbines in cars, it has been tried. A maker of microturbines, Capstone, ran a test of a 10kw microturbine genset in a small car a couple of years back. Looking at their web site now, they do have gensets, 30kw and 65kw, for larger vehicles, like busses. These cost more to buy, but are much cheaper to maintain and get much better mileage than standard diesel engines. I don't have any information on why the smaller turbine project was not pursued. If these types of systems were used for trucks and busses, though, it would lower our use of fuel overall. In addition, they can run on multiple fuels, liquid and gas. My experience was with gas, but they can also use diesel and kerosene. Perhaps in the future they will be sized for automobiles.
Thanks for this, Chuck! We seem to be continuing our more than century-old love affair with automobiles. Maybe that is having a strong effect on our new designs.
I'm not a powertrain engineer, but perhaps yourself or others can help me out. It's my layman understanding that modern Diesel locomotives are Diesel-Electric hybrids, having a very efficient Diesel-fueled turbine that does one thing well... it turns an electric generator. Because the turbine does one thing well, it can be optimized for power, torque, fuel-consumption, etc. to produce electricity. The electricity is then used to power the traction motors that have no mechanical transmission or clutch -- all through the magic of magnetic field induction. The electric motors do one thing well, they turn the drive shaft. As far as power goes, Wikipedia lists that a modern Diesel locomotive can start moving trains weighing in excess of 15,000 tons. The M1 Abrams tank uses a 1,500-hp gas turbine engine, but uses a mechanical hydrokinetic transmission.
I continue to be perplexed as to why the Automobile industry does not integrate technology that has been successfully developed by other industries. I would have thought that General Electric would have used their turbine expertise to capture the automobile market by now. And I don't know about you, but as far as keeping the motorheads happy, if folks get excited about a "turbocharged" engine, I would love to be on the marketing team for the first "turbine jet" powered commercial automobile...
What should be the perception of a product’s real-world performance with regard to the published spec sheet? While it is easy to assume that the product will operate according to spec, what variables should be considered, and is that a designer obligation or a customer responsibility? Or both?
Biomimicry has already found its way into the development of robots and new materials, with researchers studying animals and nature to come up with new innovations. Now thanks to researchers in Boston, biomimicry could even inform the future of electrical networks for next-generation displays.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.