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-   -   Bionic Van (https://ecomodder.com/forum/showthread.php/bionic-van-3948.html)

Big Van 07-20-2008 05:08 PM

Bionic Van
 
I'm sure everyone on this forum has heard of the Mercedes "Bionic car" based on the boxfish... I'm wondering if I could apply any of its principles to modding my 15 passenger van, as suggested here:

Fuel Efficient Vehicles Now! - Bionic Vans Trucks & Buses

Or maybe something like this:

AeroTruck 1

The boxfish car claims a Cd of .19. I know the enormous area of a passenger van would blunt the effects of a slippery shape, but I figure anything's worth a shot.

Can anyone enlighten me as to why the Mercedes's shape is so much more efficient than a normal van's? Could I work some kind of cloroplast wizardry to emulate it on my own vehicle? Thanks!

Daox 07-20-2008 09:26 PM

Well, the overall shape is quite a bit more aerodynamic than a conventional van. You could definitly work on rear wheel skirts and an under belly pan.

aerohead 07-21-2008 06:55 PM

van
 
Conventional vans are for hauling,and are optimized for useful interior volume.So you get a lot of floor area you can stack stuff,right up to the ceiling.Its a cubist's dream come true! The down side,is that vans tend to be slab-sided,with very little plan- curvature ( curvature to the sides when viewed from above),and a relatively flat roofline.--------------------------------------------- This means that the van is basically a "full wake" vehicle.The cross-sectional area of the van,from the windshield back,is constant,at full projected frontal area,until the very back of the van.This means that the wake of the van is also the size of the full cross-sectional area of the van.Really big!!!!!!!!!!!!!!!!!!!!!!!!! ------------------------------ With the "bionic" car,you'll notice that the roofline curves gently down as it projects towards the rear of the car.Also,if you were above the car,looking down,you'd see also,that it was growing ever so slightly more narrow from front to back.This is where the Cd0.19 comes from.--------------------------------------- For your van,the air is disturbed from it's "rest" position,knocked out of place and accelerated to about 1.3-times the velocity of your speedometer,and since there is no narrowing of the body,the air stays completely out of equilibrium,until the van passes,where it tumbles into the void left behind the van,creating an enormous wake of turbulent air which cannot convert itself from its state of kinetic energy,to the calm,atmospheric pressure air it was before you came along.This in essense is your aerodynamic drag.--------------------------------------- And for your van there is no easy remedy,as the only way to get the air re-organized without turbulence,requires a lengthy tail.You could do all the mods you see for the Fed Ex concept truck.This would reduce the forebody drag,when combined with a full bellypan.You might see Cd 0.20.------------------------------------------- If your at say, Cd 0.38 now,and you could cut drag to 0.20,that's a 48% drag reduction,and would be good for about 24% better mpg at 55-mph,a little better at 70-mph,I don't think you could do better unless you cut into the roof and sides,and re- designed the rear 1/3rd of the vehicle.All your time trouble and material expense would have to be recouped in fuel savings.And you'd be losing interior space.--------------------------------------- A boat-tail will give you some savings,but the extra length can be a real issue when parking.-------------------------- you may want to do a ecomodder search for aero-mods # 11(aftbody streamlining/boat tails),there is some empirical data for you to peruse and may be of benefit to you.

Big Van 07-21-2008 07:29 PM

Thanks, Aerohead, your explanation was really helpful. So I guess the best thing to do is to try to go from "rough brick" to "smooth brick" with a belly pan, wheel skirts, etc. I might also try something like this for long hauls where parallel parking isn't an issue:

Green Car Congress: New Boat Tail Design Could Improve Class 8 Truck Fuel Economy by 10%

I don't think I'm ready to invest in the ultimate solution:

AeroTruck E-38096: Air flow testing on aerodynamic truck

NeilBlanchard 07-21-2008 08:28 PM

I think the comparison between the van and the Bionic "Boxfish" car is reaching.

aerohead 07-23-2008 07:19 PM

Aero truck
 
Quote:

Originally Posted by Big Van (Post 46147)
Thanks, Aerohead, your explanation was really helpful. So I guess the best thing to do is to try to go from "rough brick" to "smooth brick" with a belly pan, wheel skirts, etc. I might also try something like this for long hauls where parallel parking isn't an issue:

Green Car Congress: New Boat Tail Design Could Improve Class 8 Truck Fuel Economy by 10%

I don't think I'm ready to invest in the ultimate solution:

AeroTruck E-38096: Air flow testing on aerodynamic truck

What NASA did is what I did to my VW van in college.Rear skirts,full bellypan,and 18-inch long boat tail.She could hit 35 mpg on a good day.You can make the bottom more horizontal than NASA did.If you can deal with the extra length,they're money in the bank!

Big Van 07-23-2008 07:24 PM

Whoa, that's encouraging! Since the thing's already as big as a whale, an extra 18 inches isn't terrible... Maybe I can make it so it folds flat against the sides of the van when not in use.

aerohead 07-23-2008 07:40 PM

That's the trick.And the jury is still out,with respect to the "best" solution.I did a fan-powered inflated tail also and it worked well.It was a crude proof of concept and I'll probably re-visit that one.If you look carefully at the NASA link photo,you'll notice that the tail starts out with very little curvature.The further it goes,the steeper it gets,to a point where it follows basically a constant angle from there back.If you start too steep,the flow will separate,with little benefit to your wallet.Scale that photo to your van,and you ought to be good to go!

dadag 07-24-2008 11:12 AM

just for fun

http://www.uni-leipzig.de/~mielke/ma...sich/truck.jpg

http://www.design-cars.com/component...signTrucks.jpg

aerohead 07-24-2008 04:08 PM

I don't think the World is ready for Luigi Colani.I think the atmosphere is though.

MazdaMatt 07-24-2008 04:24 PM

What... the... hell... is... that?

aerohead 07-24-2008 05:07 PM

Wait 'til you see how he dresses!

azraelswrd 07-24-2008 05:13 PM

truck in the 2nd pic on the right looks somewhat more decent on the aero... very cool designs in any case.

aerohead 07-24-2008 05:21 PM

Colani took a bunch of his creations to Bonneville including the 18-wheeler.It was quite the candy store! Some designs were more flambuoyant than others.I don't remember what the truck scored,but I remember the Cd was quite good.And as Marie Antoinette has said"We've already forgotten more than we'll ever learn."

dadag 07-24-2008 05:36 PM

What's interesting in the very limited size of the grill compared to what you usually see on the road, especially here in the US.

aerohead 07-25-2008 04:16 PM

grill
 
Quote:

Originally Posted by dadag (Post 47334)
What's interesting in the very limited size of the grill compared to what you usually see on the road, especially here in the US.

Yeah,it suggests that a lot less power(and heat rejection) is needed to push that bad boy down the road.

Big Van 07-25-2008 06:24 PM

Unfortunately, of all the people in this world who are not ready for this fellow, long-haul truckers are probably the least ready...

aerohead 07-28-2008 05:41 PM

ready
 
Quote:

Originally Posted by Big Van (Post 47692)
Unfortunately, of all the people in this world who are not ready for this fellow, long-haul truckers are probably the least ready...

It would be unfair for me to make any generalized comment about long-haul truckers.I have known some on each end of the spectrum,some in the middle.I would have thought economics would have been enough to drive 18-wheeler development.Guess I was wrong.Perhaps husband/wife team drivers will come to dominate the driving field one day.Then,perhaps the wives can all threaten divorce,unless all the husbands agree to allow" Effeminate" modifications to the family trucks and trailers,and the wives get to "girl-it-up".Then the "men" can blame the "women",and family harmony,for their having to put up with these un-manly,yet clean and economical high performance trucks and trailers.Wilma and Betty take the heat,while Fred and Barney sock it away in the bank.

Big Van 07-29-2008 10:54 AM

My apologies to truckers... I guess the only information I have about them is from "Smokey and the Bandit," which probably isn't a reliable source.

Good point about the economics, though. You would think that companies such as Wal-Mart, for whom cheap transportation is a real cornerstone, would be really interested in this sort of thing. Pretty soon transportation costs are going to affect their business model, and their board members won't really care if the trucks are a bit outlandish looking.

MazdaMatt 07-29-2008 12:07 PM

My family's bread and butter is trucking. My father owns a company, two uncles drive trucks, my brother and two cousins are mechanics.

Yes, it is fair to say that many truckers are big-block lovin, manly men.

However, i think the reason for lack of change is financially driven as you'd expect the reasons FOR change to be. With a sudden up-shot in deisel prices, many companies are struggling in this industry. You can't just change your fleet over to more efficient trucks. A new "typical" truck is like a hudred grand. Some technologically advanced engineering spectacular would cost much more. That buys a lot of gas and uses a lot of money that these companies just don't have right now.

i_am_socket 07-29-2008 01:05 PM

Very true. My fiance's family has a trucking company and the pickins are slim. The best you could do now for a more aero truck is hope you know someone with some scrap sheet metal and a welder to test with.

And yeah, they're manly men who love their Harlies, red meat, and mass produced beer-like products. They're also not the brightest, but they're family so it's ok ;-)

You figure out how to quickly and cheaply retro-fit existing trucks to reduce fuel costs by even 5% and you'll have yourself "the better mousetrap" for which people will beat a path to your door.

aerohead 07-29-2008 04:13 PM

economics/big government
 
Quote:

Originally Posted by MazdaMatt (Post 48737)
My family's bread and butter is trucking. My father owns a company, two uncles drive trucks, my brother and two cousins are mechanics.

Yes, it is fair to say that many truckers are big-block lovin, manly men.

However, i think the reason for lack of change is financially driven as you'd expect the reasons FOR change to be. With a sudden up-shot in deisel prices, many companies are struggling in this industry. You can't just change your fleet over to more efficient trucks. A new "typical" truck is like a hudred grand. Some technologically advanced engineering spectacular would cost much more. That buys a lot of gas and uses a lot of money that these companies just don't have right now.

Most people seem to hate government intervention in any aspect of their lives.Today,in the US,EPA mileage figures on new cars are drawing much interest.Funny thing,those numbers wouldn't exist without "big government".Class-8 truck manufacturers have done what they can with their tractors,with no pressure from the EPA.They're kinda deadlocked now with mpg,because very little has been done with trailers.Just supposing,what would happen if the EPA had "voluntary" goals for 18-wheeler mpg,as associated to the truck/tractor combination,say,10-mpg? Perhaps there would be incentives for any company to step up to the plate.Something like the Program for New Generation Trucks(PNGT),like President Clinton tried to do with automobiles,which were supposed to go on sale last year,with 80-mpg.By the way,are the car makers going to return all those millions of taxpayer dollars they received to produce a car they never manufactured? Inquiring minds want to know!!!!!!!!!!!!!!!

MazdaMatt 07-29-2008 04:19 PM

I think it would be VERY difficult to mass produce a truck or trailer who's additional cost due to engineering offset fuel cost by enough to make people's heads turn. The construction of a brick-like trailer is just so simple compared to something more aero. That simplicity likely also makes it less weight and more durable/repairable. Every time I'm in dad's shop there is a trailer there with a bent bumper or scrapes down the sides, or a gash in the roof. If it was made of some wavey-shaped fiberglass it would be more expensive to repair.

aerohead 07-29-2008 05:03 PM

cost
 
Quote:

Originally Posted by MazdaMatt (Post 48819)
I think it would be VERY difficult to mass produce a truck or trailer who's additional cost due to engineering offset fuel cost by enough to make people's heads turn. The construction of a brick-like trailer is just so simple compared to something more aero. That simplicity likely also makes it less weight and more durable/repairable. Every time I'm in dad's shop there is a trailer there with a bent bumper or scrapes down the sides, or a gash in the roof. If it was made of some wavey-shaped fiberglass it would be more expensive to repair.

Seems like all the engineering is behind us.Hucho's extensible boat tail image from the 1930s would get us most of the way there.In my photo album there's an article about the Fruehauf/International combo from the 1980s,which got 10-mpg.Sure,you might have to pay a royalty to the first guy out of the chute.But that didn't keep people from building electric light bulbs and paying Edison for the privilege.And yes,OTR operators would have something else to deal with,but the Waggoners are already dealing with it,and may be in business long after others have fallen by the wayside,because they could not compete against the increased mpg of the competition.My aunt and uncle were one of the first husband/wife OTR teams in the US,and my uncle was also a pilot,had been a flight instructor during WW-II,and he definitely new the connection between aero and 18-wheeler mpg.Beyond driving an "ant-eater" and installing "Nosecone" on all the trailers,there wasn't muchin the marketplace for him.I was too young and cash-poor to make a difference.Now I'm older and still cash poor! Frustrating! We lose billions each year.We just pile 'em up into mounds and set fire to them.Computers vs typewriters.Everybody seems to understand that one.But when you put wheels on something,people go immediately stupid.Shame.

MazdaMatt 07-29-2008 05:14 PM

You mistake science and engineering. Yes, the science of it is well-known in the aero field. You need an engineering firm to make the drawings and test the concepts. Sounds simple, but it ain't (I figure you know that much!)

So how does a kam-back truck hold the same amount of freight as a box-shaped truck? make it 10 feet longer? that is out because if htey could make it 10 feet longer, it would be square, and hold 8 more skids to make more money than the kamback could recoup in fuel. Okay, make it some sort of accordian fold-up deally that you deploy for hte highway. Now you're talking about a 15-thousand dollar piece of heavy equipment if you want it to last for 20 years problem free. What if it breaks? Does your in-house trailer repair dude know anything about fixing it? Nope, send it to a specialty repair shop for 5 grand. And what does a heavy piece of equipment like that weigh? factor that into the fuel equation, and MUCH more importantly, tell the trucking company that their maximum load has just been reduced by that much.

Much much much much more to the puzzle than simply "toss on a kam-back and a nose cone".

Everything in that industry is SIMPLE and STRONG. Those are the prime requisits.

aerohead 07-29-2008 05:49 PM

science/engineering
 
Quote:

Originally Posted by MazdaMatt (Post 48841)
You mistake science and engineering. Yes, the science of it is well-known in the aero field. You need an engineering firm to make the drawings and test the concepts. Sounds simple, but it ain't (I figure you know that much!)

So how does a kam-back truck hold the same amount of freight as a box-shaped truck? make it 10 feet longer? that is out because if htey could make it 10 feet longer, it would be square, and hold 8 more skids to make more money than the kamback could recoup in fuel. Okay, make it some sort of accordian fold-up deally that you deploy for hte highway. Now you're talking about a 15-thousand dollar piece of heavy equipment if you want it to last for 20 years problem free. What if it breaks? Does your in-house trailer repair dude know anything about fixing it? Nope, send it to a specialty repair shop for 5 grand. And what does a heavy piece of equipment like that weigh? factor that into the fuel equation, and MUCH more importantly, tell the trucking company that their maximum load has just been reduced by that much.

Much much much much more to the puzzle than simply "toss on a kam-back and a nose cone".

Everything in that industry is SIMPLE and STRONG. Those are the prime requisits.

I know I'm being simplistic.The thing about the Fruehauf trailer,is that one presumes all the engineering has been collecting dust since the 1980s.The blueprints are finished,the science is firmly established,the concept has been proven at the Diesel pump,and it is only a matter of someone in a position of authority to sign the go-ahead for production.Their design was a high-cube,longer trailer with more cargo capacity than conventional trailers.More cargo per mile.More range per fuel load.Lower cost/ton-mile.No increase in load on power-train,perhaps less.No moving parts,just the rear cargo split-door as already in acceptance.The weight of the skirts would be offset by the decreased wall height in the boat-tailed area.
Throw in the flotation tires.If I were the government,I'd have the national labs develop no-cost technology for "convoy" driving,allowing truckers to NASCAR draft,bumper-to-bumper in trains ,say,up to 10-rigs long,dedicate lanes for them to do it in,and imprison any motorists in cars which endanger the truckers,driving coast-to-coast,saving up to 15% in the draft.

MazdaMatt 07-30-2008 09:29 AM

Okay, I definately need to go and look up that specific trailer idea. That sounds good.

Now... freeway drafting technology, THAT is something that truckers could accept! You'd need ONE patented technology (preferably a standard, not a product) that was cost effective so you get massive market saturation as quickly as possible. You would need equipment attached to trailers AND trucks and control systems to manage speed and more importantly inter-vehicle communication. When the first guy in line slams his brakes, ALL the trucks need to slow down at an equal rate. Considering load differences, you'd probably be able to get by with at least a 10-foot following distance, which would be spectacular for fuel savings. If one guy is too heavy, the others around him would have to immediately compensate to give him cushion.

When I drive my cube van (see my thread for horrible FE details), it is WONDERFUL when I can get into a convoy; I lift my foot up about an inch and a half and maintain the same speed. When that convoy is 2-lanes wide it is even better.

MazdaMatt 07-30-2008 09:35 AM

Is this it?

Most of the info I found when searching for Freuhauf was about current designs, them losing business, and recalls.

aerohead 07-30-2008 03:55 PM

Nope,that's not it.Let me look at the other posts,see where we are,and I'll jump in.

aerohead 07-30-2008 04:36 PM

is this it?
 
Quote:

Originally Posted by MazdaMatt (Post 49122)
Is this it?

Most of the info I found when searching for Freuhauf was about current designs, them losing business, and recalls.

MazdaMatt,I checked my photo album,and it looks like I never posted the article about the Freuhauf/International truck/trailer combo.There's some other stuff but not what I wanted to share.I've got the article,it's from CAR and DRIVER I think.I can try and scan it and email it to the aero forum or I could mail a copy to you. Since so many everyday-use truck items are standardized(glad-hands,pintle-hooks,Hub-o-meters,etc.)seems like we could have a national standard for convoy stuff and trailer stuff.Anyone could manufacture as long as they respect the standard.Perhaps the cost of royalties are underwritten by the taxpayers(as we all stand to benefit).Nationwide parts and service,universal familiarity,everybody can work on it.Maybe it's so good,it never breaks down! Massive public education programs could bring all motorists up to speed in a matter of a few months,as to how important the drafting could be,not only for the U.S.,but everyone.The impact would quite literally ripple through the entire economy.It would be a way for the government to put it's mouth where it's money is.Our money! I've tried to find fault with the idea,other than it would mean reduced fuel tax revenues to the states and federal govt.


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