by the end of this topic i want to be fully baked..so if you dont mind pass this back, and tell me what you think...
ok a "race car" (sarcastic) has a muffler and a rear spoiler. that makes a.noise and b. downforce to hold your race car to the road. forget about a. ...f*ck a. lets think about b. angle b. the spoiler the otherway and create "upforce" woulndt this make the car lighter ...making it easier to keep the same speed like on the freeway?> mythbusters just validated "drafting" behind a semi will increase fuel economy by alot, so why not create upforce on a big ass suv and make it lighter? peace
no free lunch here, the "lift" it will produce will use energy from the car by adding drag, whether you install the spoiler backwards or not.
An agressive spoiler on a race car will improve stability at the cost of speed.
the angle of your spoiler no matter what direction will cause friction.
i thought of drag, but what if the lift is the higher number of the equation, or on another level what about an airplane wing, in the 60's people too that concept to boats and it was called a hydrofoil, the water travels over the top of the foil faster than the bottom creating a low pressure zone, this whould lift the boat completely out of the water, a 12ft aluminum boat with a 30 hp motor would go like 40mph.
if somekind of airfoil was used then it would have to work, i stuck with the spoiler for ease of explination. picture a airplane wing mounted on top of a car like a spoiler, i know would be creating lift with less drag, finding the perfect balance i bet one could achieve some good freeway miles to the gallon.....(https://overunityarchives.com/proxy.php?request=http%3A%2F%2Fi237.photobucket.com%2Falbums%2Fff156%2Fvdubdipr%2Fallme.jpg&hash=e828ac38c2fd985630f85c618e3ca627b806f8ee)
vdubdipr]
Sorry
Some Ideas just arn't practical.
I don't think that using a wing to lift a car will save any energy . But lets say that it did .
Lets also say that we made a car that was 50% supported by the wing at 60 MPH
What happens to the brakes of this car when half the weight of the car is supported by the wing?
How sharp of a corner could you turn at 60 MPH? Or 90 MPH ?
How much crosswind could you handle?
WHat bout hydroplaning ?
Race cars use spoilers that increase drag because the spoilers in effect increase the effective weight of the car for breaking and traction . This allows them to drive fast more safely .
gary
There have been many designs created and lately discarded that made cars more slippery to the air.
I agree there will be no free lunch, but sailboats do go fast with no motor, just aerodynamics.
So, the thing to design would IMHO be something that uses the air driven through already to come back and for the same mpg to pust the car along.
I am thinking of a cup (a metal spinnaker) at the back of the car.
A thing that makes the air at the BACK of the car turn around and push the car. It would look familiar, but much more exaggerated.
Who is a metal fabricator?
Can you make one for a robotic car and measure battery usage oor something?
Go for it, vdubdipr, and let us know.
jeanna
No don't go for it! we still need u alive more than dead.It is car handling hazard as stated above.boat goes faster because it is lifted from more dense water to the air,and friction of a boat moving under water (700 times more dense than air) is way bigger than the same boat fighting with an air drag.U have no chance of moving ur car to some less dense medium by lifting it ;)
What u can do is to make a special spoiler that reduces the turbulence behing ur car it would surely help ur mileage.
Car mass matter less when it is steady moving(only the rolling resistance and air resistance counts).Tires friction depends on car mass but it is the thing that keeps u on the road even in the turns,it is a grip.Would u like to trade a grip for mileage?Winter is a good example of what it means to have no grip.
During the acceleration is the moment ur car mass counts a lot.
acceleration is given by a formula:
a=F*m
where the force of ur engine is F and mass of ur car is m.So to accelerate a heavy car the same way u accelerate a light one ,u need to push it harder (so engine uses more fuel).
@jeanna
ur cup idea is exactly the way a parochute works...and we all know what is expected from parochute.(drag racing cars use it to brake from high speeds)
Quote@jeanna
ur cup idea is exactly the way a parochute works...and we all know what is expected from parochute.(drag racing cars use it to brake from high speeds)
Ok I meant the cup pointing the other way around.
I am not a car person, but I am a sailor. I understand what you said about the frix of the water. ok
but if a spoiler is that little bar across the back window of a car, then what I mean is to exaggerate that.. The top of the parachute pointing to the front of the car, not behind catching the wind.
I also think it ought to be such that the edges of the cup and sort of "axion" of the cup should be directed down and forward a bit.
This is hard to describe. try this: Picture the skinny end of a tornado ;D pushing a car. create a vortex that moves you forward.
I also was thinking of a toy car, not a real one. cheaper parts and way safer.
I hope this clears it up a little. Sorry for any confusion.
jeanna
na i found something:
http://www.mitsubishi-motors.com/corporate/about_us/technology/review/e/pdf/2004/16E_03.pdf
some research was done.It reduces the total drag of a car by 0.006 coeficient.It is ok number if they speak about what i think they speak :) typical car has something like 0.27-0.39 if i remember it right.
Aja but they seems to forget about the side mirrors.This small vortex creators could be attached form under,side and above the mirrors to reduce the drag :)
another link on aerodynamics,looks interesting but i haven't read fully:
http://www.recumbents.com/car_aerodynamics/
it looks like the under the car there is a lot to improve the aerodynamics!
personnaly i like the removing of side mirrors and placing a camera's there,it will be probably in few years in standard cars.
In motorbikes without the side mirrors u can get as much as 15 km/h more of top speed (and it is in range of 300km/h) so i take it as an argument of substantial drag introduced by mirrors.
yeah some good intel here ....but.... ahhh if your car, had some wings, it could fly, and so could a crotch rocket with a turbine, and retcractable rear wheel, hmmmm.
if the wing creating lift was adjustable then as the conditions change so would the foil to the operaters determining calculation.take it to the extreme _do heavy ass cars get better or worse gas mileage than light cars? do manufacturing plants make some cars light on purpose? do semi trucks use more gas than a 2 door import? think less people would hydroplane in rain if the had more wieght "on demand"? can an airplane glide without a motor? is that called a glider?
@creativity...grip for mileage i would trade on a sunny day in a suv that weighs 3500 lbs over the same car wieghing hypotheticly 600lbs. mythbusters did get 8 miles a gallon by puting it in a draft
the foil could be built with perameters that limited capabilities to reasonable wieght loss per vehicle spec. by creating lift this could eliminate detramental effects of wind resistance / rolling resistance or account for a large percentage of it. this foil would only serve its purpuse on long freeway road trips.
@reson : resulting brakes would have intial drawbacks but after a speed is decelerated to when foil is not making alot of lift then its not an issue. id imagine a big difference between 40 and 60 mph. foil could have automatic computor controlls, once brake pedal is pushed to a certain point the foil could turn down and increase brake proformance. or turn down when it senses water. foil could even be used as a brake all by itself to save your pads...downshift the foil....not the car...... i think the most unpracticle idea is that there would be a sharp corner on the freeway.
so keep coming at me with some shit and ill flip it on you ;D cheese... picture that
a car would have to work less, requireing less power/ RPM to move it along if it was lighter. any arguments with that?
someone can make an airplane wing that would make a car glide easy...
so IMHO saying something that makes sense after that acronym would lead me to belive im right.
think of how fast a 270 hp suv could get from 60 to 100 miles an hour if it only weighed 600 lbs the whole time, electronicly adjusting itself, even a bigger suv with like a 350 hp engine freeway acceleration if it weighed alot less. that shit would be tight
@ jenna im a sailer myself .."downtown girl, milwaukee wisconsin" 27 foot j boat. or the 17 ft, hobiecat and i always get free lunch cuz im pretty... i pull up the the clubs on my boat... the "slut shuffle" 15 foot fiberglass which im working on hydrofoils for, but i own my own flooring company and am always helping people in need so o dont have alot of free time between hydrogen experiments, so itll take some time.
and the only way id mount a steel spiniker or a jib,on my car is if i got hit in the head real hard by the boom and my brain indicater was damaged
you can make anything fly, by intellegent design. just how much is needed for a car is all we need to figure
All any of this would do is to increase drag. There is no way around it. Spoilers on race cars ARE airfoils. (airplane wings) NACA tested hundreds of airfoil designs long ago and determined their lift over drag coefficient (L/D) and assigned them numbers. What you have in any airplane is a compromise of the lift created vs the drag created by the airfoil. Bush planes that need to take off from short fields have high lift airfoils. Their maximum velocity is greatly decreased by the added drag. Conversely, aircraft designed for high speed flight do not develop much lift at all and need much longer runways and do not make very good gliders when there is a power loss.
Jeanna mentioned sailboats. There is such a thing in sailing called hull speed. This is true for any boat. It is the primary limiting factor on the top speed the craft can go on a given power ratio. In other words, if a hull is designed for 20 knots, you can add a larger motor, or more sail area, but the effect on the top speed will be one of diminishing returns once the hull speed is reached.
Drag increases as a square of the velocity, so in your car, the drag at 40 mph is not 2 times the drag at 20 mph, it is 4 times. This adds up very quickly.
I don't mean to trash your idea. Thinking is good. Lighter cars do get better mileage, or at least, have the potential to. This is basic physics as in less mass to accelerate, climb hills, etc. The best way to make a vehicle lighter is to make it lighter in a static condition. When I look at our vehicles and all of the crap they put in them, it is amazing we get the mpg we do get. I remember a Hotrod magazine article from the early 70's where they took a stock Cadillac to the drags and ran it down the 1/4 mile. I think it ran like a 16 second quarter. then, the techs began to remove stuff from the vehicle, seats, window glass, radios, spare tire, etc. They ran it again and it was down to about 14 seconds. Then they got a torch and removed a bunch of "unneeded" sheet metal from the car. (Bumpers, fenders, etc.) Anyway, the point is that after they were done, the last run was under 12 seconds. That is a fantastic improvement without even tuning up the engine or adding any speed parts. By altering the power to weight ratio, they achieved better results than if they added 350 hp to the car's engine.
Anyway, keep thinking. It is good to not accept the way things are and want to make a change. Car makers could easily be doing so much more. We buy what they sell so they don't have to change.
Bill
Quote from: vdubdipr on June 08, 2008, 12:23:54 AM
take it to the extreme _do heavy ass cars get better or worse gas mileage than light cars? do manufacturing plants make some cars light on purpose?
do semi trucks use more gas than a 2 door import?
think less people would hydroplane in rain if the had more wieght "on demand"?
can an airplane glide without a motor? is that called a glider?
heavy cars get worse mileage and i explained why,during acceleration u need more power to work against higher inertia of a car.
semi is less aerodynamic and hevyier.
I don't get what u r asking with this rain hydroplane...
airoplane can glide without a motor and it does so by declining,gravity is responsible for a froce to accelerate the glider and create the speed so it can generate lift on the wings.Lift makes it decline at lower rate,there is a limit at what point the glider stalls and begins to fall.That is when declining rate is to small and windgs can not produce enough lift to hold the glider.In some reagions of atmosphere
warm air is convecting upwards making it possible to bring glider higher to prolong the gliding.Lower weightof the glider mean thet wings can produce enough lift with lower declining rate.
Quote from: vdubdipr on June 08, 2008, 12:23:54 AM
@creativity...grip for mileage i would trade on a sunny day in a suv that weighs 3500 lbs over the same car wieghing hypotheticly 600lbs. mythbusters did get 8 miles a gallon by puting it in a draft
the foil could be built with perameters that limited capabilities to reasonable wieght loss per vehicle spec. by creating lift this could eliminate detramental effects of wind resistance / rolling resistance or account for a large percentage of it. this foil would only serve its purpuse on long freeway road trips.
wind resistance have nothing to do with mass but with shape,i hope u see it.Adding of spoilers would increase the wind resistance as Pirate mentioned.
Lower weight will decrease the rolling resistance.
Quote from: vdubdipr on June 08, 2008, 12:23:54 AM
@reson : resulting brakes would have intial drawbacks but after a speed is decelerated to when foil is not making alot of lift then its not an issue. id imagine a big difference between 40 and 60 mph. foil could have automatic computor controlls, once brake pedal is pushed to a certain point the foil could turn down and increase brake proformance. or turn down when it senses water. foil could even be used as a brake all by itself to save your pads...downshift the foil....not the car...... i think the most unpracticle idea is that there would be a sharp corner on the freeway.
so keep coming at me with some shit and ill flip it on you ;D cheese... picture that
so u got our point and it made u to think it over and to adjust it.So the shit hit the right spot ,buy a 12 pack of WC-paper and be prepared for more shit coming ;D adding this controlling system would help for sure to drive saftely. Speaking of a sharp corners i recently fell out of the road in a rainy day when taking a highway exit with only 40mph...it can be done.
Quote from: vdubdipr on June 08, 2008, 12:23:54 AM
a car would have to work less, requireing less power/ RPM to move it along if it was lighter. any arguments with that?
someone can make an airplane wing that would make a car glide easy...
no arguments with that ,i stated it in my previous post already ,but when moving at steady speed on a even road weight accounts for tires friction.On this u can play with ur spoiler idea.It is not so much friction but acceleration conditions/hills climbing that make u to use much more fuel in heavy car.In hill climbing u have to use ur fuel to work against gravity to bring ur car higher.By accelerating u work against car inertia,and car inertia depends not on the weight of the car but on its mass.if u see the difference u will notice that lifting a car won't change its inertia.Inertia can be ony changed by taking off the mass of the car,not its weight.Again Pirate said it already.
Summarising,by introducing a foil u add extra aerodynamical drag and decrease the car weight by lift.By reducing the car weight u achieve lower rolling friction.
just found this...what do youall think of it???? http://www.pureenergysystems.com/news/2005/03/08/6900067_RamWingUpdate/
Howdy,
Any airfoil that you add to the shape of the body is going to increase drag. Forming a vortex requires energy and you will notice the energy loss. Take a clue from aircraft. They, except the wings and horizontal and vertical stabilizer, are as aerodynamic as possible. Anything that cuts the air causes drag. You have to use energy to overcome drag. The lower that you can make the coefficient of drag the more energy you can put into velocity. One of the fastest vehicles that I can think of is a Top Fuel Dragster. It has a tiny cross section, coefficient of drag, and almost no body. Of course they are extremely dangerous also.
Here is another thought. Inertia is the enemy of velocity. If you want to increase the velocity of the vehicle, reduce its inertia like Pirate88179 said. But lets do it in a non-conventional way. Use some alien technology and install inertial dampeners, or inertia cancelers. This way a tiny amount of power can propel the vehicle at high speeds, and you will be able to corner like you are riding in a tube car. If you have a great amount of power you might break relativistic speed records. I know this is totally unconventional, and those inertial dampeners from the 24th century are really hard to get. But, why not do something unconventional like fill large empty spaces in the vehicle with air bladders, then fill them with helium or hydrogen to cancel some of the inertia? You could also remove all the unnecessary stuff like spare tire, extra battery, tool box, case of depleted uranium rounds, etc...
Blessed Be Brothers...
You guys keep thinking about wind resistance. The true question is, what relives more friction from the entire vehicle moving forward a wing or no wing.
The bearings in the vehicles drive train and wheel get hot from more weight and make plenty of wasted energy.
Same with deflated tires also.
Will the wing reduce more friction with the moving parts of the car or will it create more friction with the passing wind?
Thats the question
Not just wind resistance!
To add a wing to a 3500 pound car you would need a wing wider than most highways. You also would need more engine power to overcome the increased drag.
By driving behind a Semi you do use less power but that is because you are reducing the iar friction (volume of air) striking your car. A vacuum would be ideal but is not reality.
QuoteTo add a wing to a 3500 pound car you would need a wing wider than most highways
NOT
EVEN
CLOSE
we are not talking about complete lift off
reduction of only a few hundred pounds makes a big diff. for that only a small wing is needed at 60+
LIKE I SAID what causes more friction the cars moving parts or the wind? thats the question.
thanks hal for the back up... it would be interenting to see some math on DRAG VS WIEGHT.
maybe they effect eachother. but i think to a certain point if drag is minimized there would be a net gain for wieght loss by airfoil...
got math anyone?
well to find out really what may work better just compare the two. Heat and friction on moving parts under a load
VS wind friction on the wind foil.
HEAT & FRICTION = moving parts
WIND FRICTION= wind foil
the packed bearing and metal on metal in my mind create way more lost energy then a wind foil.
so it seems as tho a wind foil may relieve the moving parts on the vehicle adding MPG reducing wasted energy
Sorry Haliburton, you are not even close. The bearings used today are not frictionless, but nearly so. There is a lot of precision that goes into making them. A bearing does not "know" how much weight is placed upon it. It only knows the coefficient of friction it was designed for. Lighter is better yes. No argument from me on that. I said as much in my previous post. But, to use the wind to "make" the vehicle lighter is a losing game. The math is simple. (I suck at math) the drag from wind resistance increases as a square of the velocity. This is math. This is proven. You can't get something for nothing. An airplane, just before it lifts off, may only weigh 20 lbs. But, it paid a price in horsepower to overcome the drag created by the lift generated by the wings. Aircraft have a much higher power to weight ratio (more math) than automobiles. They have to.
@ vdubdipr:
I really don't mean to sound like the voice of doom here. I am just going with accepted math and physics that have been understood for many years. Possibly, with your line of thinking, you may come upon some other overlooked technique that can work. I love creative thinking, I really do. Just because no one has thought of something before does not make it a bad idea. Some will tell you it does. I don't think so. The Wright brothers were told by many "experts" that heavier than air craft can not possibly fly. (These included the top scientists of the day and college professors) Well, we know differently now.
So, don't give up. Keep thinking! Just remember to use the known laws of physics (such as they are) in your planning so you do not have to re-invent the wheel.
Bill
Well say what you want but try this for example:
Get a front wheel drive car, remove the back wheels and drive it down the road.
You probably will not get good MPG
Now take that same car and put a wing on the back to lift the rear axle off the road.
I would bet a beer that the car with the wing on the back will not only get better MPG then the one without but it would also act as a normal car under the right speed in a straight line.
Like i said before what has for friction. the moving parts of a car, or the wind hitting the wind shield
QuoteThe bearings used today are not frictionless, but nearly so. There is a lot of precision that goes into making them. A bearing does not "know" how much weight is placed upon it.
So tell me Billy what creates more heat and more noise and more wasted energy
Wind on a smooth wind foil or bearings packed in grease under a heavy load
QuoteLighter is better yes. No argument from me on that.
If lighter is better that means a wind foil would be better as long as it created less friction in the momentum forward then the moving parts under a heavier load right?
Haliburton:
As another already posted, the airfoil would not change the mass and therefore the inertia. This is the most significant portion of the mileage equation I believe. I'll take your beer bet and say that it might actually be pretty close. Yes, friction is a parasite but so is drag. Friction does not increase exponentially, drag does. (as relates to air resistance) I am not a scientist here and have no definitive answers. I just look around and see some things for myself.
As I have tried to say, I think we are all on the same side here. I am just trying to say to keep physics and known science in the mix or some will be chasing their tail.
Again, as far as your bearings question, I have personally machined very low friction, extremely high precision ceramic bearings in my lifetime and the wind on the airfoil would offer more resistance for sure. But, don't just take my word for it. Look it up, ask others. I really don't think I am wrong on this but I am not perfect. Always good to know.
Bill
i dont know pirate, the higher i get the more i think it will work... did you try that?
Ok well i do understand what you mean by having bearing that are just about frictionless.
What about the tires on the vehicle.
From what i understand, cant you like lose up to like 20% MPG with tires that may not be inflated all the way.
The tires have a inflation limit for over inflation explosion purposes and stopping power.
Would the wind foil reduce the amount of tire and pavement friction increasing MPG??????
Also would the wind foil act as a air suspension for your vehicle, if so maybe that up and down force on the wing could be harnised some how just like solenoid
Could the wings have some sort or angle like a plane where if you hit the brakes they return to making no lift but down force, increasing the weight of the vehicle in turn increasing the stopping power or turning power.
So in other words the brake and gas power would control the up and down of the fin reducing and increasing the friction put upon the tires and pavement?
its seems as tho it may work ;D
In the 1960's, there was a race car called the Chaperal. (may not be spelled right) This car won a lot of races until it was banned because it had a rear spoiler that would be set to the straight position for high speed and as the driver approached a corner, he moved the spoiler to a position that would put heavy down force on the car for the turns. (you can google it) an added bonus was that the airfoil created tremendous drag in the deflected position which helped the car slow down for the turns (road course) thereby saving the brakes. The other racers said it was not fair so it was banned.
The 20% increase in mileage figure you mention for properly inflated tires seems very high to me. It is true that properly inflated tires offer lower rolling resistance as compared to under inflated ones.
Another example of how important drag is on a vehicle, in the "old" days, it was better to not run the ac and roll the windows down because the ac compressor takes about 15-20 hp. Now, with cars that are much more aerodynamic new studies say that you get better mileage with the windows up and the ac on.
The single best way to increase gas mileage has to do with the driver. I read some stuff the other day about "high mileagers" that hold competitions to see who can get the best mpg on their vehicles. I think the winner got over 110 mpg! People every day get over 60 mpg from their minivans. Most people would not drive like they do, and also would not want to be behind any of them on the road. They accelerate very slowly and seldom use the brakes. They say that if you have to use the brakes, you have not anticipated the road conditions properly. If they know they are going to make a turn, they slow down way before the turn so brakes are not needed.
I'll see if I can find that site and post a link here. If everyone drove like them, we would have more gas than we could use.
Bill
thanks bill i see your point of view and understand your thought process, unfortunately i have to leave withought further adu because the p[olice are coming they are gettin at me because i knockeout the brother and other guy who have been peeipning throught my sositers windows bye gtg peac4 thanks again but i got wat=rr3nts for my arrenaws a nd the nieghbors are in ther mifdddle ofg fthe srteeet
Riiiiiiiiiight
seriously that shit was crazy, this guy has been peeping threw my sisters windows for 2 years and i finally caught his ass. he got 1 punch and was knocked to the ground, his brother caught an elbow to the dome and they both ran in their house after i kicked dude in the head on the ground, i narrowly avoided the police man if i would have taken 2 more seconds typing that last post i would have been locked up for assult and had to serve my 1200$ in tickets in time on the bench, dam,n what a crazy incedent, im not violent but when it comes to my sisters im a freakin pitbull... i still cant believe that shit went down like that... my hand and elbow hurt with joy! i hope this shit deosnt come back and kick me in the ass like shit usually deos..... but we have over 30 times where we called the police on him, so if he was tresspassing im all good right????????
I am a licensed private investigator and, if he was on your property, and invading your sister's reasonable expectation of privacy, he should go to jail. You should easily beat any criminal charges of assault but, he could still sue you in civil court and win. Just like the burgler who tripped on a skateboard while breaking and entering a house....he sued in civil court and won because he got injured while committing a crime. To me, that is screwed up beyond recognition.
Bill