Increasing efficiency - converting heat?

[Jayslay420]

curtis,
Thanks again for your input. I'm still caught up on the heat convertion, althought the exhaust driven alternator is an interesting plot. Could be far easier to apply then what drew suggest below, though doesnt really capitalize on the radiant heat as much.


Drew,
Those numbers I gave are not really accurate, just some figures I've heard. The main point is that a very considerable portion of inputted gasoline is wasted as heat during the combustion. Thank you though for the back-up data. Interesting about the thrust factor of the Spitfire! I have thought about thermocouples a bit, just not enough. How many windings are needed? In fact, I may just go do some reading right now... I'm guessing you would need some voltage regulation and storage for the electricity produced?

[drew300]

I just remembered - somewhere I read that the radiator housing (Spitfire) by cancelling drag, gave them another 140 hp to the airframe.
Thermocouples: you'll probably read much more than I know. I'll assume that the longer the twist, the more current. I'd expect somewhere around .3 to .5 volt, but I'm guessing. I wondered about replacing a muffler with a "box" full of these, to lighten the load on the alternator. - Store the juice in the battery.
Didn't Ford have a 2 speed drive belt system, to lower parasitic loses? ie; turn the water pump and alternator slower. (on a Mustang, I believe)

[kachok25]

One way to get better thermal effecency it do decrease the surface to volume ratio. Using fewer larger pistons with a longer stroke will reduce the amount of surface area for the heat to be absorbed into. But of course larger pistons, crank and rods means lower redline RPM but more torque.

[beef_bourito]

good idea but you'll also have more surface area on the cylender walls for the heat to be absorbed into. I believe the hemispherical heads provided the best thermal efficiency yet (the HEMI engines). check it out on www.howstuffworks.com.

[CBFryman]

Originally Posted by beef_bourito

And a turbo doesn't add eficiency, in theory it should but it adds exhaust backpressure that makes the engine work harder, also it adds air and fuel so you're burning more fuel per stroke.

THe backpressure caused by a turbo is minimal compared to the enrgy it gets from exaust heat to compress air to raist engine efficency.

my idea was to use a small, high compression engine (higher comrpession = Better thermal efficency) and run Alternator, AC, and powersteering off of the rotation from a turbo.


Turbine engines are efficent...however to get them to work it takes alot of fule...which means they just make alot of power

If you are just looking for great MPG Hybrids arent the way to go. Remember that no energy transfer can be 100% efficent so converting motioni nto electricity and then into sored chemical energy and back to electricity and then back to motion is a HUGE waste of energy. Look at the 0-60 times . that is how they get the MPG they do. get a car of similar weight and put a smaller, high compression engine in it with some type of VVT that produces enough power to get the same 0-60 times and the non hybrid will have better MPG.

Also, Hybrid's downfall is they shut the engine off and then start it up when needed. We all learned in basic automechanics that an engine is least fule efficent on start up, even if it it warm.

[beef_bourito]

yes but i was proposing a turbine hybrid, turbines aren't very efficient on acceleration but are extremely efficient for constant speed. this way you could have it running at a constant speed and transfer energy to the batteries. it could runn very low and only accelerate when the batteries were running low. it could probably be alot more efficient than todays hybrids and get good 0-60 times (because electric motors have great torque) and it would be easier to limit speeds (if parents didn't want their kids to be going 100 miles per hour).

[Moppie]

Turbine Hybrids are already in common use, but not in automotive aplications.
They get used in large ships, in tanks, and sometimes in locomotives.

The problem is the size of the Turbine needed to produce enough power, its to big for safe, and easy street use.
Turbine powered cars, where the turbine had a direct link to the wheels have been built in the past, but they all suffered problems with very high heat.
If you exhaust it out the back you melt or burn anything behind you (no good in traffic) and venting it out the top can create issues with visablity through the heat haze.

[kachok25]

Originally Posted by beef_bourito

good idea but you'll also have more surface area on the cylender walls for the heat to be absorbed into. I believe the hemispherical heads provided the best thermal efficiency yet (the HEMI engines). check it out on www.howstuffworks.com.

Not really remember I said few, larger, pistons by chomparing a 4 inch bore to a 6 inch bore we have roughly twice the displacement with only about 33% more surface area. Put V8 displacement into a large bore 4 cylinder engine with half the nimber of cylinders and it will only have about 83% of the surface area at a lighter weight but at the loss of high RPM.

[drew300]

I thought all the big bore stuff had problems with emissions. That's why Chrysler and Ford brought out V-10s. Also, 4 cylinders above 2.2 to 2.5 L have balance shafts, I can't see spinning parasitic wieghts help efficiency.

[Alastor187]

Holy shit, BMW steals Jayslay420's mistrusted IC steam engine idea….

Originally Posted by Gizmag

December 14, 2005

A large percentage of the energy released when petroleum is burned disappears out the exhaust system as heat. This has always been the case but the amount of energy released looks set to be cut by more than 80% thanks to a new system devised by BMW. BMW’s announcement of the new technology is somewhat of a technological bombshell as it adds yet another form of hybrid automobile – a turbosteamer.

The concept uses energy from the exhaust gasses of the traditional Internal Combustion Engine (ICE) to power a steam engine which also contributes power to the automobile – an overall 15 per cent improvement for the combined drive system. Even bigger news is that the drive has been designed so that it can be installed in existing model series – meaning that every model in the BMW range could become 15% more efficient overnight if the company chose to make the reduced consumption accessible to as many people as possible.

Combining the innovative assistance drive with a 1.8 litre BMW four-cylinder engine on the test rig reduced consumption by up to 15 percent and generated 10 kilowatts more power and 20 Nm more torque. This increased power and efficiency comes for, well, … nothing. The energy is extracted exclusively from the heat in the exhaust gases and cooling water so it is essentially a quantum leap in efficiency.

The Turbosteamer is based on the same principle of the steam engine: liquid is heated to form steam in two circuits and this is used to power the engine. The primary energy supplier is the high-temperature circuit which uses exhaust heat from the internal combustion engine as an energy source via heat exchangers. More than 80 percent of the heat energy contained in the exhaust gases is recycled using this technology. The steam is then conducted directly into an expansion unit linked to the crankshaft of the internal combustion engine. Most of the remaining residual heat is absorbed by the cooling circuit of the engine, which acts as the second energy supply for the Turbosteamer.

The development of the assistance drive has reached the phase involving comprehensive tests on the test rig. The components for this drive have been designed so that they are capable of being installed in existing model series. Tests have been carried out on a number of sample packages to ensure that the BMW 3 Series provides adequate space. The engine compartment of a four-cylinder model offers enough space to allow the expansion units to be accommodated.

Ongoing development of the concept is focusing initially on making the components simpler and smaller. The long-term development goal is to have a system capable of volume production within ten years.
“This project resolves the apparent contradiction between consumption and emission reductions on one hand, and performance and agility on the other,” commented Professor Burkhard Göschel.

Link: http://www.gizmag.com/go/4936/

[Moppie]

Originally Posted by Alastor187

Holy shit, BMW steals Jayslay420's mistrusted IC steam engine idea….

Link: http://www.gizmag.com/go/4936/

Look like most of us were very wrong.

Heres some more links: http://www.google.co.nz/search?hl=en...osteamer&meta=

[Jayslay420]

Well, now that its been done already, i have to move on to something else. Thanks for all the support guys...