Some deep thinking on getting Best MPG in a VAN

[freebeard]

Someday you will be my age.

The math is r=√A2. r is the radius of the front corner, 4" is probably close. You can measure that from where the front is flat to the edge. Square root of A squared is A () Likely six feet plus. 4 over 72 is the nut you have to crack.

Mirrors are a necessary evil. That mount is not. Yours are placed where the air flowing off the windshield is trying reattach to the side. Moving them forward of the A-pillar opens that up.

I ride the bus a lot. If I [were to] stand on the curb, those new mirrors would still bean me.

You want simple? Here's a design proposal that was actually tested on a trailer but could be applied to the headlight area on your van. How to increase the front radius without cutting into the body:



https://ecomodder.com/forum/showthre...tml#post481517


Designed for a camper (where it works really well clearing the door swing) implemented on a trailer. In your case it could be clear covers over the headlights.

[racprops]

[QUOTE=freebeard;580291]Someday you will be my age.

Tell me are you OVER 70??

I think it is more likely that some day YOU will be MY age.

The math is r=√A2. r is the radius of the front corner, 4" is probably close. You can measure that from where the front is flat to the edge. Square root of A squared is A () Likely six feet plus. 4 over 72 is the nut you have to crack.

Mirrors are a necessary evil. That mount is not. Yours are placed where the air flowing off the windshield is trying reattach to the side. Moving them forward of the A-pillar opens that up.

I ride the bus a lot. If I [were to] stand on the curb, those new mirrors would still bean me.

You want simple? Here's a design proposal that was actually tested on a trailer but could be applied to the headlight area on your van. How to increase the front radius without cutting into the body:



https://ecomodder.com/forum/showthre...tml#post481517


Designed for a camper (where it works really well clearing the door swing) implemented on a trailer. In your case it could be clear covers over the headlights.

Very interesting. As I live in 110 degrees AZ, I fear blocking my grill for causing over heating....

And of course I made things worst by opening up the original turn signals to use as farther openings for my transmission and engine oil coolers...

BUT What IF having the air dam and side skirts keep air out from under the van creating a mild vacuum that then helps PULL the air that would be a blockage FROM the engine compartment so that air flows though the A/C condenser, radiator, fan and then flow right out from under the van???

So that is is not a big pile up of air in front, but a free flowing air system??

Right NOW (Before the engine failure) That Van ran at 190/200 degrees at 85 MPH, 55MPH or stand still idling with the A/C keeping the inside nice and cool in 115 degrees HOT AZ summer.

I am not a mind to mess with such a great working system.

Now some of the outside stuff like wipers covers, and some kind of cover for the drip rail, perhaps something for the mirror mounts I might even consider wheel covers for the back wheels...

And some changes to the back.

Rich

[freebeard]

Whatevah. It's not a contest. I don't try to leak personal info to the unblinking eye of Internet, but I was born into a world without atomic bombs.

cooling: https://en.wikipedia.org/wiki/Meredith_effect

Pulling that air out of the engine compartment requires air flow. Your side skirts are Okay except for adding frontal area in cross-winds. You could double them up and trap air turbulence off the wheels.

Best practice with an air dam seems to be to have a central notch to put a high-speed jet down the centerline of the underbody, with a belly pan. And all that influences the diffuser design.

Wrap clear plastic in one piece from the inside of the headlights to the front edge of the front wheel well (you can incorporate air curtains) and the inner half of the curves forms a bellmouth to the radiator opening (important).

And some changes to the back.

An annular ring would create a box cavity without adding length. In the length of a trailer hitch shelf you can gain ~5% gas mileage.

[racprops]

A world with out atomic bombs...OK that places you before 1945, so as I was born in 48, that does mean I have some catching up to do.

So any chance you ca render some drawings of what your suggesting, I cannot quite get a picture.

Rich

[freebeard]

You don't know how hard I'm trying to avoid having to, but you asked nicely [enough].

It won't be instantaneous. My choices are a Sharpie sketch snapshot or a new program, Krita. Maybe time to learn a new program.

For now here is a bellmouth. They are mostly round or oval but they can be rectangular


http://www.ductdirect.com/SpiralPipe...tsSpecs/BM.gif

The outer half rounding into an air curtain needs more hand-waving. Here's a box cavity:


http://www.curbsideclassic.com/wp-co...mage/28078.jpg

IIRC 20-->24MPG.

[racprops]

Interesting, I take it you did that on your mini van??

And I am figuring you note "IIRC 20-->24MPG is the change from 20 MPG to 24MPG with JUST that rear frame and canvas shell??

Standard question, that change was due to that shell alone??

Thanks for trying to help me understand. I am kind of thinking add a trunk to the rear deck and it would look less odd to other cars.

Rich

[freebeard]

It's a different world here in Ecomodding Central. It's a well-known story in the Aerodynamics subforum.

A friend of aerohead's built it in the last century. He drove it to Mexico and back once a year. You can dig out the details there. I'd be skeptical of a 20% improvement since the bottom is left undone. The point though, was about the box cavity. Here's a less extreme example:



If you care, the more extreme example would be Morelli's Urban Car.

[Hersbird]

I drive a mail truck, and some of the new prototype designs have mirrors out like that bus. The problem on the current mail truck is the mirror either blocks side visibility at an intersection, or slams you in the shoulder when you get in and out. I'd say that bus is done to improve side visibility especially at say a 4 way stop. It may have also then shown to improve aero, but I know first hand classic mirror placement kills visibility


here is a picture of what would be the blind spot out front with cross traffic. Imagine standing a little forward of where this picture was taken and the mirror fill the window meant for 1/4 ahead visibility.

[Galane]

Ah, the Grumman LLV, built on a Chevy S-10 frame. Designed for a 20 year lifetime 30+ years ago. Windshield washer hose routed above the fuse box so when the hose deteriorates and cracks it can leak and catch fire. No insulation, no air conditioning.

https://www.trucks.com/2017/11/06/tr...ivery-vehicle/

[Hersbird]

Originally Posted by Galane

Ah, the Grumman LLV, built on a Chevy S-10 frame. Designed for a 20 year lifetime 30+ years ago. Windshield washer hose routed above the fuse box so when the hose deteriorates and cracks it can leak and catch fire. No insulation, no air conditioning.

https://www.trucks.com/2017/11/06/tr...ivery-vehicle/

And I think I just became the maintenance administrator for a fleet of 74, mostly LLVs. At least mine are all the 1994 models so only 24 years old.
There is something great about their simplicity. I really doubt whatever replaces them is anywhere near as daily relialiable when they are 15 years old, let alone 30.