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Tuckerfan
12-14-2005, 08:33 PM
http://www.theautochannel.com/news/2005/12/09/166247.html

<font face="Verdana, Arial" size="2">Using an innovative concept, BMW Group Research and Engineering has succeeded in harnessing the biggest and as yet untapped source of energy in the car: Heat. Combining an innovative drive assist with a 1.8 liter BMW four-cylinder engine on the test rig reduced consumption by up to 15 percent while generating nearly 14 additional horsepower. At the same time, up to 15 lb-ft more torque was measured. This increased power and efficiency comes free of charge. The reason is that the energy is derived exclusively from the waste heat present in the exhaust gases and cooling system and doesn’t cost you a single drop of fuel. The research project meets all the conditions espoused by the philosophy of BMW Efficient Dynamics – lower emissions and consumption combined with more dynamic driving and performance.</font>It's an interesting idea, and I hope that BMW starts mass producing them, since it seems like the design would offer better overall fuel economy than hybrid cars (which really only save gas in city driving). However, VW was supposed to install a "heat battery" on their cars about a decade or so ago, which would have enabled their cars to have lower emission levels on start up, but nothing seems to have to come to pass on that point.

[This message has been edited by Tuckerfan (edited 12-14-2005).]

CCWKen
12-14-2005, 09:16 PM
Oh great, we're going back in time. I'd rather see nuclear powered cars. Fill it up once and drive the rest of it's usable life.

Or, force the car builders to use the technoligy they already own--100+mpg gas powered vehicles.

With GM and Ford sucking air now, maybe they'll finally build some useful cars.

Tuckerfan
12-14-2005, 09:21 PM
<font face="Verdana, Arial" size="2">Originally posted by CCWKen:
With GM and Ford sucking air now, maybe they'll finally build some useful cars. </font>Given what Ross Perot said about GM and how insipidly stupid Ford has been, I wouldn't hold my breath.

J Tiers
12-14-2005, 10:52 PM
"innovative"? Maybe, if you go by the worthless patents issued these days....

About as innovative as a waste heat boiler aboard ship from around 1920, or various schemes for extracting energy out of exhaust mere recently.

Significantly more problematic however.......

To get your plates, you would need your annual safety equipment inspection (lights, brakes etc), your annual emissions inspection, and NOW, your boiler certification as well...... http://bbs.homeshopmachinist.net//eek.gif http://bbs.homeshopmachinist.net//biggrin.gif

Norman Atkinson
12-15-2005, 02:15 AM
Moving just off a bit, it would appear that
the Queen- Elizabeth Alexandra Mary has decided to have a heat pump in Buckingham Palace.

One wonders if it is plugged in to the bedroom of Charles and Camilla.

Or into the State Banquetting Rooms in readiness to make use of the energy from the Burning Bush.

Just a thought- just another!

Norm

Spin Doctor
12-15-2005, 09:43 AM
Why not just use infrared photovoltaics to reduce the electric load on the engines electric system? Just kidding.

PTSideshow
12-15-2005, 12:38 PM
Here is another link about that steamer but the magazine web site and the other topics may prove to be more interesting.
http://www.gizmag.com/go/4936/

------------------
Glen
Been there, probally broke it doing that

Spin Doctor
12-15-2005, 02:07 PM
I really like the looks of the Holden show car

[This message has been edited by Spin Doctor (edited 12-15-2005).]

Evan
12-15-2005, 02:26 PM
The P-51 Mustang made excellent use of waste engine heat. It was largely responsible for the high performance of the aircraft. The Germans never did figure this out during the war since it didn't show up in wind tunnel tests.

By appropriate placement and design of the radiator and ductings under the fuselage the P-51 was able to recover nearly all of the energy normally lost to cooling drag. The rad system acted like a mini jet engine and contributed up to 350 lbs of thrust which almost offset the 400 lbs of drag created by the radiator assembly at speed. Cooling drag is a big item in high speed piston propellor aircraft and in this case the drag actually went down as the speed went up.

lynnl
12-15-2005, 03:12 PM
Cooling drag? That's a new on on me. Could you elaborate a little.

Is that referring to a thermodynamic process, or some mechanical drag resulting from cooling features of the acft?

Ron LaDow
12-15-2005, 03:31 PM
lynnl,
I'm not Evan, but...
WWII piston-powered aircraft design dealt with 'installed drag'; both the size/shape of the power plant and the induced drag of any water/oil coolers.
Air cooled engines gave up drag from the engine itself, although this was largely mitigated by the ring surrounding them.
Water cooled engines had a slim frontal area, but the oil and water rads had to be exposed to the air flow somewhere or other.
As Evan mentions, no other design got close to the P51, although even that ugly lump under a Spifire's wing was ducted to minimize the drag (gain some thrust from the heating).
Thanks,
Ron LaDow

Evan
12-15-2005, 03:42 PM
All piston aircraft engines require cooling to operate. Whether air cooled or water cooled there must be airflow over either fins or a radiator. With an air cooled engine this is via ducting through the front of the engine cowl, through the engine compartment and out through some sort of port such as cowl flaps. The velocity of the air as it exits is lower than the velocity that it entered at and this imposes a parasitic drag penalty. This is known as ram drag. As this slower air exits the engine compartment it by necessity flowing along the fuselage or wing and disturbs the airflow over those parts increasing the drag there causing additional parasitic drag. This can be a significant fraction of the total drag of the airframe. The cooling drag can amount to as much a ten percent of the total airframe drag even with a well cowled engine.

The same applies to a water cooled engine as the air flows through the radiator. The feature of the P-51 design was both the placement of the radiator and the shape and length of the ducting. The air was slowed and then heated by the radiator causing it to expand and with a properly shaped duct it exited at a higher velocity than it entered.

Kansas_Farmer
12-15-2005, 04:21 PM
Which is all find and dandy until you get a 7.92/12.7/20mm hole in the radiator, then it sucks to be you...

Gimme a big round engine like the PW R2800 in that Thunderbolt any day. You can shoot entire jugs off of it and it still doesn't care.

lynnl
12-15-2005, 04:22 PM
So, it's that portion of the total drag imposed by the cooling system. (...was afraid it might be something more exotic. ...maybe another eider-pinion phenomenon)

Personally I've always liked that distinctive lump on the bottom of the P51's fuselage. Makes it look more intimidating somehow. Prettiest airplane ever made in my view. I could kick myself for passing up the chance to fly in one when I was stationed at Ft Rucker, AL many years ago. The Army Avn Test Board had two rennovated (F-51's they were designated) that they used as chase planes for the cobra and cheyenne test programs).

Kansas_Farmer
12-15-2005, 04:47 PM
'cept the Spit and the "runstang" look like they should be in the air races, all nice and sexy like.

The 109 and 190 look like they were designed to do 1 thing. Kill!

Norman Atkinson
12-15-2005, 06:09 PM
I'm sort of sitting with a R J Mitchell mug full of coffee! It has a Mk1 on it but the newer marks seem to be forgotten. SL721- JMR -a Mk LF16E is still about but she had a Griffon 65 engine.This old girlie could screw the arse off anything with pistons- and with a higher ceiling. Jimmy Robb's kite had every rivet filled and Johnnie, me old engine basher wore plimsoles.

One of the other old girlies was Boothman's old Spit. Boothman was one of our gaffers and won the Schneider outright in a floatplane Supermarine S6B which was almost as fast as a Mustang P51.Boothman drove it to outright victory in 1931!

The only thing that set the P-51 in the history book was its range- and eventual speed with decent British powerplants.
The Packard Merlins and the Allie's were crap. End of story!

One of the greatest difficulties faced was cooling and whilst the S6B had radiators along each side of the fuselage- hull, it wasn't really on to build them into a warplane to be easily riddled in combat.

Just for the record, we had the famous 3 at Hendon. PM 659, SL721 and TB713. In addition, we had the Spits of the County of London 601 and the County of Middlesex 604 Auxiliaries before they moved to Vampires at North Weald. I suppose that I was one of the last to see a pair of Spitfire Squadrons in action together. My old much lamented neighbour was a Seafire jockey in the later Korean Shindig. The rest of his family went for the classic four minute swim in the Fleet Air Arm.
Me old engine basher and rigger and me old clerk are still alive. Just us four, I think!

Big Geordie.

Tuckerfan
12-17-2005, 01:58 AM
Here's a similar idea to BMW's that dates from 1924. http://www.dself.dsl.pipex.com/MUSEUM/POWER/still/still.htm

<font face="Verdana, Arial" size="2">The main idea of the Still engine is to increase overall efficiency by using the hot Diesel exhaust to boil water, which then drives a steam engine, which is combined with the Diesel, sharing the cylinder.</font>

Norman Atkinson
12-17-2005, 02:25 AM
For the old wartime film buffs, I recall one in which an oil tanker was torpedoed in the North Altlantic. Determined to get to the UK with what was left of her precious cargo it was impossible to light fires to cook. They used the engines' exhaust to cook the food.

Well, it's called "San Demetrio, London"
If any of you youngsters out there want to know the contribution your older people made to us, this is it.

Norman

bobbybeef
12-17-2005, 06:52 AM
When I was a kid we had up to 32 Clydesdale heavy draft horses to do the work. It was good working a plough drawn by the full team. Took a bit of tacking up in the morning and the fuel consumption was high and they had to stop for rest and watering at pretty short intervals.
The big problem was as always fuel. We used to get about half a ton to the acre in those days so we had to plant a lot of oats for grain to cover all the work horses and also the house horses; saddle and jinker.
There was also the need to cut one big mother of a haystack or two of sheaves of hay;wheat and oats and rye. Then we had to do it all double or trebble in the good seasons to lay in reserves for the drought seasons.
So with all this early rising and growing oats was I glad when the Fordson tractor arrived. The beautiful big horses all went off for very small prices.Ten shillins each I recall was all we could get for animals that had annually earned thousands of pounds.
This is reported in this stream because once I am gone every one will want to ride horses,pull carts with them and might even race the fast ones.Steam cars Bah they will never catch on.
bobby.

Evan
12-17-2005, 09:14 AM
We had a couple of percherons staying with us a few years back when a neighbour had his property horse logged. They sure have a nice disposition. It seems the bigger the animal is compared to average the nicer they are. Real gentle giants.

jim davies
12-17-2005, 09:23 PM
"...The Packard Merlins and the Allie's were crap. End of story!..."

As for the Packard Merlins, Rolls-Royce felt differently. They state that the engines are interchangeable as to performance, durability etc.

The "inferiority" of the Allison is all about the supercharger. The R-R Merlin 60 series had a good, 2 speed 2 stage centrifugal when ealier models of the Allison V-1710 had a single stage, low-rated blower.

What the 1710 had that was superior included connecting rods and combustion chamber shape. Later 1710's had superchargers which were as adiabatically efficient as the Merlin/Griffon. It so happened that production schedules and overall supercharger length made the Merlin a quicker swap to get the high altitude performance wanted. I refer you to the R-R Heritage Trust's "RR and the Merlin" and Schlaifer.

RR had a winner with the Merlin and the later Griffon. Not necessary to boost them by knocking other engines. RR never did.

jim davies
12-17-2005, 09:24 PM
"...The Packard Merlins and the Allie's were crap. End of story!..."

As for the Packard Merlins, Rolls-Royce felt differently. They state that the engines are interchangeable as to performance, durability etc.

The "inferiority" of the Allison is all about the supercharger. The R-R Merlin 60 series had a good, 2 speed 2 stage centrifugal when ealier models of the Allison V-1710 had a single stage, low-rated blower.

What the 1710 had that was superior included connecting rods and combustion chamber shape. Later 1710's had superchargers which were as adiabatically efficient as the Merlin/Griffon. It so happened that production schedules and overall supercharger length made the Merlin a quicker swap to get the high altitude performance wanted. I refer you to the R-R Heritage Trust's "RR and the Merlin" and Schlaifer.

RR had a winner with the Merlin and the later Griffon. Not necessary to boost them by knocking other engines. RR never did.