Has anybody modified the airflow on their flat nose to decrease drag?

[jfmusic@me.com]

I would expect a v-spliter or Rounded above and below the windshield would greatly reduce drag.

Thoughts

 

[fo4imtippin]

I got 12mpg on mine for my 2000 miles home at 63mph. I have since unlocked 6th gear, but added a whole lot of things to drag on like a roof rack. I feel like i would have to cone the whole thing to make it much better. I read that putting skid plates under and reducing bottom drag would make a more meaningful difference. I see trucks and things adding the skirts, but don't see as many looking like airplanes. I would expect they would have enough miles to see the difference.

 

[magnakansas]

Nope, but

You can make wall with low drag coefficient when you put a tapered tail on it.

Get all the stuff that disturbs air flow off the roof and sides.

Side cameras instead of mirrors.

If you do a roof raise…. The tallest up front with a 7 degree taper for the last five feet or so - Yarn testing would give you idea for the shortest distance that would yield results. The 7 degree part is pretty much written in wet cement.

Disc wheel covers on the rear wheels.

Undertrays… smooth up underneath. Problem is you have to maintain airflow over the engine block and transmission….. this is part of the cooling. Same for rear differential. Negative pressure behind radiator - make any air that gets into low pressure zone go through the radiator package.

The ideal is to get the air to join back up behind the bus.

Laminar air flow is the key to drag reduction. A long bus has less drag than a short bus of the same design.

Biggest return? SLOW down.

William

 

[turf]

i think about this a lot.

for my flat nose bus, i think i could improve aero a couple of ways.

on the roof above the driver:
it needs built up and rounded over, like the leading edge of a plane wing.
at the rear of the bus, extend a boat tail end a foot or so beyond the end. kind of like what you see on semi trailers that deploy while driving.
the last thing is wheel covers and air vortex generator tabs.

 

[Albatross]

I honestly find the idea kind of funny, TBPH. Because no matter which way you're looking at a flatnose, it's a brick wall.

But hey, a mile/gallon is a mile/gallon. And I'm usually adding a few hundred miles when I go someplace.

 

[Booyah45828]

https://www.nosecone.com/products

They make "bubbles" for the front of box trucks that supposedly increase fuel economy. It'd be something to look at on a conventional bus above the windshield.

Not sure what you could do on a transit.

Moral of the story is to look at what fleets do, as those guys can save millions per year by saving tenths of an MPG fleetwide. Things like wheel discs, under fairings, and trailer tails are all something to look at or incorporate. Even super singles can supposedly gain you mpg.

 

[Albatross]

Personally, I would think that fairing the underside of a bus out would have more effect than probably about anything else.

 

[Meathead]

Well there’s this[emoji2]



The Albatross Chronicles; bird meets Blue Bird, silliness ensues
https://r.tapatalk.com/shareLink/to...ead.php?p=182530&share_type=t&link_source=app

 

[Albatross]

HAH!

That's definitely one way to do it.

 

[mmoore6856]

as you probaly noticed the trailer tails are disappearing. there was no fuel savings on them. when you talk of aerodynamics you can not use airplane design as we do not go fast enouh and with the trucks we found out they work but only when you are going straight into the wing . that seldom happens as roads curve. they do not work with any side wind. also the morons that forgot about them when backing up was friggn funny. air dams, a light foot and avoiding the flat fronts seem to be the way to go

 

[cadillackid]

as you probaly noticed the trailer tails are disappearing. there was no fuel savings on them. when you talk of aerodynamics you can not use airplane design as we do not go fast enouh and with the trucks we found out they work but only when you are going straight into the wing . that seldom happens as roads curve. they do not work with any side wind. also the morons that forgot about them when backing up was friggn funny. air dams, a light foot and avoiding the flat fronts seem to be the way to go

I had through the traler tails and wheel covers actually worked but that there issues with them getting damaged by ill backing attempts then parts of them flying off on the road after damage..



my biggest thing to increase MPG is slow down.. sure I built a bus that frankly hauls ass but driving it at those speeds the MPG's goes down real quick.. running 65 nets a good mix of MPG and still making miles.. my preference in the vintage busses is to run 55-60 which nets great fuel Mileage.. smetimes less mileage.. as when you drop the speed smetimes a better route to drive is off of the freeway.. but of course you increase your time factor..


I personally dont drive the bus when im in a hurry.. I recently ran a rather fats road trip to get some A/C equipment that was needed fast.. I wouldve preferred to drive a bus because its more fun.. but the HEMI got the job because quickness was of essence in this case (A/C equipment in july)...


its a trade off.. a trade off that every hot-rodder has known for decades..

More speed == More Spendy. the same is true for busses.. you can make em go fast and do what you can to reduce drag (like not raising roofs and mounting solar panels or roof decks, etc...) but of course you lose features you may want / need...



another factor that few ever pay attention to are weather patterns on the days you travel.. head winds / tail winds / cross winds are a much bigger factor in your MPG than you may think..



for instance.. Beating a cold front with a leading low pressure system by heading northbound or east bound.. has a lot of precedence for getting a good tail wind. Low pressure systems spin counterclockwise.. staying ahead of one moving east / northeast by travelling ahead of it by a few hundred miles your MPG will go up..


trying to Beat a cold front by "getting out of dodge".. "holy crap snow strm is coming im heading to florida".. yeah you'll be running in a head wind headed south...


mountain areas are often subject to heavy winds on certain days and not others... you can watch the general patterns and pick your days to be in motion..



many times winds of all times will drop off overnight unless there is a weather pattern change coming (storm system marching)..



use the Big Box effect to your advantage when you can

 

[mmoore6856]

I drove with a large company that had a over 1000 trucks and they tried those tails on about 10 using the best drivers. We tried to make them work as we got fuel bonus but we did not see any improvements. I got a ticket in one state for being over length that cost me a hundred dollars. Anyway our managers decided they were snake oil

 

[Meathead]

Elon Musk on aerodynamics.

https://youtu.be/qpCYyC6xm-g

[emoji1]Dave

 

[shorthair-SKO]

I drove with a large company that had a over 1000 trucks and they tried those tails on about 10 using the best drivers. We tried to make them work as we got fuel bonus but we did not see any improvements. I got a ticket in one state for being over length that cost me a hundred dollars. Anyway our managers decided they were snake oil

Trailer builders have gone to NACA ducts at the sides and top at the rear and are seeing a fair result fuel efficiency wise and it's a much more reliable system than the old tails that might deploy. BTW if the tail doesn't deploy the driver has no way of knowing. Oops.

 

[Mr P]

I'm considering some of the previously posted info as I plan my roof raise.

A possible "cheap/easy" solution for the drag of turbulence at the rear of a bus is the mounting of a tent to the rear...just putting that thought here for now. Before I forget it....