Just so you know I've been browsing through this site and I think some of things you guys try are a little loopy. Dont get me wrong, some are ingenious, practical, heck it even looks like fun. But yeah, a little odd Keep going I say.
the bow bulb on a ship has to do with the interface between water and air. The bulb lifts the water ahead of the ship, which then falls away from the above water bow. Apparently its takes less work to lift the water than to push it aside (air is more compressible than water, and one is pushing against air when lifting the bow water).
I always wondered how those bulbs made it easier for the ship to push through the water... that explanation makes alot of sense! I never thought of it that way. Thanks for that! Kinda gave me a eureka moment there...
I wonder about a bracket up front with a ball or bulb leading the way, like that bulbuous thing on the hull of a ship that parts water. Make it a sliding-adjustable arrangement with the bulb leading the grille.
The History Channel had a program about the Japanese Imperial Navy's flagship,Yamato.The project was very classified,and the nose of the ship was top-secret,and a hydrodynamic coup for the day,and has found its way into the U.S.Navy (USS Ronald Reagan),and Soviet Navy ships,as well as merchant vessels.According to the narrator on the TV program,the bulb created a counter bow-wake underwater,which cancelled the bowwake above waterline.Sorry! This is a little deep for me.A fellow tried this at Bonneville on a streamliner.Best I can tell,it failed to be effective.
It would be nice to have a sticky out here that broke things out in a quick reference manner:
Car mods
Prioritized list of aero mods
Truck mods
Prioritized list of mods
Realizing that various mods deliver different percentages of improvements per vehicle, these might be somewhat general. For example, with a truck, the likely top few mods might be a) lowering the truck, b) less aggressive tire tread and size, c) aero bed cover, etc.
So... unless there is some data out there that indicates smooth wheel covers are a huge saver, I would expect to see these generally at the lower end of the spectrum. I realize that this might be too precise, so grouping in general categories of top mods, middle mods, and everything else, might suffice.
Breaking this out by cars v/s trucks would be quite helpful...
Just my $0.02...
__________________ Randy
Just your average 7,000 lb 4-wheel drive 22 mpg eco modder...
"Suppose I were a congressman. And suppose I were an idiot. But I repeat myself..." - Mark Twain
It would be nice to have a sticky out here that broke things out in a quick reference manner:
Car mods
Prioritized list of aero mods
Truck mods
Prioritized list of mods
Realizing that various mods deliver different percentages of improvements per vehicle, these might be somewhat general. For example, with a truck, the likely top few mods might be a) lowering the truck, b) less aggressive tire tread and size, c) aero bed cover, etc.
So... unless there is some data out there that indicates smooth wheel covers are a huge saver, I would expect to see these generally at the lower end of the spectrum. I realize that this might be too precise, so grouping in general categories of top mods, middle mods, and everything else, might suffice.
Breaking this out by cars v/s trucks would be quite helpful...
Just my $0.02...
Randy,you asked for a very useful sticky.And while its a daunting task,I'm assembling whatever material I have and will post as I can.In the meantime I wanted to share info on some papers that basically answer your questions if you can access them.SAE Paper No. 649A "Aerodynamics for Body Engineers" by Kelly and Holcombe,1963,and SAE Paper No. 649B "The Body Engineer's Role in Automotive Aerodynamics" by Walter H. Korff,January 1963.Between the two papers,the authors lay out where all the energy is going,and in the second paper,especially,Korff lays out a recipe for Cd 0.21 cars (remember this is 1963!) and quantifies the difference between drag contributions for all body elements.SAE Paper No. 690189 "A Method of Estimating Drag Coefficients" by R.G.S.White,also lays out a cookbook approach to low drag cars,breaking a car's body into 9 categories.From the tables,one can deduce drag potential ( and elimination) within each of the 9 categories.Last paper is SAE No.760185 "The Optimization of Body Details-A Method for Reducing the Aerodynamic Drag of Road Vehicles" by Hucho,Janssen,and Emmelmann,all from Volkswagenwerk AG.Again,the paper as in the later book,breaks down a vehicles drag components and attaches numerical values to each and shows potential gains should each be realized.If you can get a copy of Hucho's book it will have all the data you seek.
Perhaps some before/after thumbnails of the particular mods to get an idea of what would/wouldn't work for your vehicle could be included along with the links?
Perhaps some before/after thumbnails of the particular mods to get an idea of what would/wouldn't work for your vehicle could be included along with the links?
Actually,Hucho's book has everything,and before and after for everything,with a quantitative assessment of everything done.Its quite a goldmine.
Actually,Hucho's book has everything,and before and after for everything,with a quantitative assessment of everything done.Its quite a goldmine.
Yeah but when I looked for that book, the cheapest copy I could find was something like $185, and it was in German, IIRC. Ich spreche nicht oder lese Deutschen.
__________________ Randy
Just your average 7,000 lb 4-wheel drive 22 mpg eco modder...
"Suppose I were a congressman. And suppose I were an idiot. But I repeat myself..." - Mark Twain
Yeah but when I looked for that book, the cheapest copy I could find was something like $185, and it was in German, IIRC. Ich spreche nicht oder lese Deutschen.
Randy,I was surprised when I read your post,however,perhaps not as surprised as you,when you saw that price! Sounds like gouging to me.I paid $80 back in '90.I saw where members were picking them off Amazon or ebay for $100.00.If it weren't in Deutsch I'd say go for it.For what it will give you its a bargain,but not with the hassle of translation.I'm pulling some materials together for those who just don't have access but it will take more time.
Keep going I say.
