Using less gas and oil to get where you're going

October 1, 2012
The honing tool adjusts its shape to match the piston bore holes. Credit: Fraunhofer IWU

A quick pit-stop at the gas station is enough to put a good dent in your wallet. New technology is set to lower the high cost of filling up your car, by enabling combustion engines to consume two to three percent less gas and signifi cantly less oil, while eliminating a step in engine production.

An engine without oil will not survive for very long. Pistons need plenty of in order to be able to move within the cylindrical sleeves in the engine block. Two things are known to raise the resultant level of friction. The first is attributed to distortion of the cylindrical bore hole when the cylinder head is attached, which is known as static distortion. The second occurs when the engine is running and temperatures warp the bore hole. The extent of this thermal distortion depends on prevailing engine temperatures and the specific engine model. In reality, the piston does not follow a perfectly smooth up and down motion, but instead touches at points within the bore hole. This results in the engine requiring a great deal more oil as well as more gas. are already able to compensate static distortion. During the final machining stage, honing, technicians mount a honing liner to the engine which simulates the cylinder head that will later be mounted. Only then the work on the bore hole is completed. Thermal distortion, on the other hand, presents difficulties since it has not been possible to compensate for this effect until now.

Saving two to three percent of fuel

This problem has now been solved by researchers at the Fraunhofer Institute for and IWU in collaboration with a and a machine tool producer. "Our technology makes it possible to compensate for both static and thermal distortion. This can lead to a fuel saving of two to three percent in , and remove one step in their production," says IWU head of department André Bucht. This clever technology is based on a tool that can adapt its own shape. Researchers start by working out how an engine block is likely to become distorted: they determine the level of static distortion by unscrewing the cylinder head and measuring the extent to which the bore hole has been warped. They then simulate thermal distortion that occurs in each engine series, using an operating temperature of 90 degrees Celsius as their reference. The honing tool adjusts its shape based on these calculations,  thereby altering the profile of the bore hole so that motions of the piston are perfectly smooth later on when the engine is running,  preventing excessive friction. Researchers have integrated small Piezo actuators into the tool which alter its shape and expand the diameter as required. "This is how we can incorporate any 'imperfections' in the otherwise perfectly round shape of the finished bore hole," says Bucht.

A prototype of the tool already exists. The researchers have put it to use to prove that they can achieve the surface accuracy required without slowing down production – there being no more than 20 to 30 seconds for the assembly of each engine. Research is currently being performed on the test rig in collaboration with auto manufacturers. This is where an engine produced using the tool is put through its paces. Researchers are examining to what extent piston and fuel consumption are reduced, and how the lifespan of the might be affected in comparison with engines manufactured using conventional tools . The tests are scheduled to be completed by the end of the year. Researchers then plan to design the tool and the production process so that they can be adopted by manufacturers.

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1.7 / 5 (6) Oct 01, 2012
So much trouble for a 2 to 3 percent less fuel usage... please invest in making good batteries and/or charge them faster.. the gas car is as good as dead... do you prefer a city with smoke from the cars no smoke (and less noise) from an electrica car? which is better for your health.....
1.8 / 5 (5) Oct 01, 2012
Agreed, the internal combustion engine is on its way out. If a fuel powered device needs to be used, a miniature combined cycle generator system would be far more efficient for electric car operation.
2 / 5 (4) Oct 01, 2012

even though e-cars have the potential to be very very quiet.. I suspect that they will not be.

I think automakers and city officials and the consumers will want cars that make noise.

You may not realize it but late at night when traffic is very light in a city, you only look when crossing the street if you hear something in that direction. Otherwise you assume you will see car lights. Quiet cars would kill these people. But we all have made those leaps of thought in our heads.

when you drive through a light right after you are through try to remember if you actually looked a the light. Most people can't remember. But if they went through it must have been green. Even better, if the car behind them followed then it must have been green.

The world is not ready for silent cars. Blind people crossing the street will be at a disadvantage. And adults who are used to noisy automobiles.
3.7 / 5 (3) Oct 01, 2012
New battery technology is being invested in like never before. However, it's very likely that the fruit of such research won't be harvested and widely implemented for many years to come. There's no reason not to continue to improve the here and now. A 'small' percentage gain in efficiency across a small fraction of the global fleet would still equate to tremendous savings. Further, there are large areas of the planet with populations that do not have access to grid electricity. If they do the grid may be unreliable and often when available it is produced locally by gasoline and diesel generators. Please keep in mind the full scope of the market when making such sweeping statements.
5 / 5 (1) Oct 01, 2012
@El Nose

You are so right. I was driving my Prius down a country road one day on battery power, and there was a dog in front of me, walking in the same direction (and thus looking directly away from me). I figured it would hear my tires even though the engine was off. Nope. I got to less than 20 feet away and had to hit my horn. The dog jumped, looked around, and scooted out of the road.

If I can surprise a dog in daytime when there are no other road sounds around, then pedestrians at night in the city are dead meat. Especially when they're distracted by whatever electronic devices they're carrying.
1.6 / 5 (7) Oct 01, 2012
Get rid of ethanol and mileage will go up by at least 3%.
2.6 / 5 (7) Oct 01, 2012
Further refining gasoline engines is fine... but not the optimum. What we need is a whole new process of moving humans in their own traveling compartments to their individual destinations.
4.5 / 5 (2) Oct 02, 2012
I think automakers and city officials and the consumers will want cars that make noise.

What consumers (younger ones particularly) need is an app that will alert them when they are about to cross a street. Seriously.
3 / 5 (2) Oct 02, 2012
The world is not ready for silent cars. Blind people crossing the street will be at a disadvantage. And adults who are used to noisy automobiles.

You are quite right. We can't have silent cars where people are involved. And they should make them louder, but they should not do them as louder as todays cars.
3.7 / 5 (3) Oct 02, 2012
Not to mention the health issue. The problems that smoke from the cars bring to the lungs are immense... Even if it's not proven, one thing is for sure. It doesn't give us good health to breath that smoke.
5 / 5 (1) Oct 02, 2012
So much trouble for a 2 to 3 percent less fuel usage...

Any improvement is better than none - especially if there are no added complications to the engine itself.
the gas car is as good as dead

For personal transport - maybe. For trucking it's going to stay a while. Hauling freights with electrically powered vehicles over serious distances in minimal time is just not in the car(d)s, yet.

Especially truck (and ship!) engines could benefit immensely from this. They use lots of oil/gas - and 2 to 3 percent savings could really add up in that sector (and trucking companies would be quick to adopt new engines, as the savings would very soon make up for the cost of a new engine)

What consumers (younger ones particularly) need is an app that will alert them when they are about to cross a street.

The ironic thing is that they would get hit while checking the app.
not rated yet Oct 02, 2012
My kightweight Harley size trike and EV sportwagon get 600 and 250mpg equivalent. What Ice's we need are very small steady rpm generators to charge EV batteries only when the battery won't have enough range. But with 50 mile range for 95% of people/US trips that will be rarely needed
not rated yet Oct 02, 2012
The best way to transport meat is to do it virtually with electrons rather than wheels.
2.3 / 5 (3) Oct 04, 2012
I love getting voted a 1 and then getting quoted and agreed with by everyone else
1 / 5 (3) Oct 05, 2012
Optimal progress requires advances on *every* frontier. Sure, by all means, break out your custom velomobile. I might do the same-- but some people will be using cars for a while yet. They may as well be as efficient as possible.

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