remove the alternator and installing it on the front of the car
 

remove the alternator and installing it on the front of the car
sorry for the typo


i have been reading about the alternator removal and i have a few questions...

1. is i remove it and place it on the frost of my car with a fan that will allow it to spin as i travel down the road, is it going to raise my CD through the roof.

2. if i install a solar panel to the roof and make it flush to roof is it going to make that much of a difference. i would run it to the deep cell batteries along with the alternator in the front of the car.

the main thing that im asking is that if i put the alternator on the front of the car and allow the wind as i travel to spin it and give me some charge. is that going to kill me or save me FE

Well, I don't know if it'll kill you, but it will add aerodynamic drag, and possibly not work at all depending on the amount of force necessary to crank it at such a rate as to provide adequate power. Perhaps if it flew off and smashed through the windshield.

As for solar panels, I think the consensus is that it either won't provide enough power or isn't very high on the ROI scale (return on investment). Unless you can get some great solar panels for free or cheaper, and if that's the case please pass on the contact info!

Even MORE gains can be had by driving on four donut spares.

Put a fan on the alternator and then make your car electric, with the motor powered by the alternator-fan. PERPETUAL MOTION MACHINE


The point is, every bit of energy you extract from the airflow around the car is energy the engine has to put back through the wheels, and then some.

Nice video... but what's the point of it? did they show any numbers? did they show that the props were even doing anything other then spining? how big of a prop ('fan") are you thinking? because... stollen from otherpower.com
wind velocity is in meters per second If we work the formula for a 5-foot diameter turbine in a 10 mph wind:

5 feet = 1.524 m swept area = pi * r2 = 1.8241m2 wind Speed = 10 mph = 4.4704 m/s So

Power available (Watts) = ½ * 1.23 * 1.8241 * 4.47043

=
100.22 Watts

and just to run the ECU on my car is 80 watts, of course I drive alot of highway miles and according to the time log built in to my under hood tac, I've averaged about 37mpg, but others average much lower and you can fingure that anything at less then about 10mph is worthless.

Sir Issac Newton called, he wanted to remind you of the first law of thermodynamics.

but isnt the winds going to be alot greater when your traveling down that road at 55, and was going to put 2 alternators on the front

Nice video. I like how the whirling blades of death are conveniently located in case of an accident. ;)

If you think it'll work, test it out and report the numbers.

That video is awesome. Why didn't Doc think of that to get his 1.2 gigawatts?

Do a search on this site for "No free lunch"... you should get your answers in those threads.

Boy, I've seen everything now. I vote for the sails....

Is it math or the physics that you don't understand?

Hey, instead of relating you somewhere else, I'll try to explain how this video is a hoax.

In modern physics, energy is not created or destroyed. Also, for every action, there is an equal and opposite reaction. **Remember these laws**

Also, since we are human, we can not produce many devices that work 100% efficiently... in fact, we do good to push 50% efficiency in most. Most modern, large, complex wind turbines max out around 35% efficient. This is using control systems for proper AoA (angle of attack), yawing, expensive generator systems, etc.

Since we know that energy isn't created or destroyed, how do the turbines extract energy from the wind? By converting some of the kinetic energy of the wind into mechanical energy then to electrical energy that is useful.

What does converting the kinetic energy of the wind really mean? It means the fast air is pushing on the blades... this pushing is called dynamic pressure. **This pressure is pushing the car backwards.** Using this pressure, the blades spin and create electricity.

How do you overcome this pressure? By applying the same amount of pressure in the forward direction. This pressure is produced by the engine. Since our engine is running off of pressure pushing the car backwards and the engine is producing a pressure forwards to counteract it, if the entire system was 100% efficient it wouldn't move or it would be accelerated to a certain velocity by an outside source and then would kick in and maintain that velocity but could never accelerate faster.

HOWEVER, like I stated earlier, we are doing good to get 50% efficiency most of the time so if this were our case, we would be pushing with half of the pressure that is getting pushed on by the turbines which means we would quickly decelerate to a stop.

That might be over complicated sounding and actually a pretty poor explanation of the subject. How about just trusting that the power obtained by the turbines is a lot less than the power it takes to push them at that velocity.

Youtube.com should have a 'B/S' tag on it to help with the ridiculous videos that get posted by scam artists.

It's also most efficent to cut out as many steps as possible when trying to get work done, like creating electricity, that is why the alternator runs off the engine and not the wind, air plains do the same thing and they have a 2nd alternator that can drop down that does run of the wind to power the controls when the engines start on fire and die but they hope never to have to use that.
also the wind at the front of the car is going to be very turbulent, as it is being compressed as it trys to move around the front of the car, propellers also have a speed range that they work well in if you go above or below this air speed then their ability to produce usable power drops off, so one designed for 50mph would hardly move at 20mph.

Looks like he could use an explanation re: hho as well.

Could you send me a link to the aircraft 'drop down turbine'? I've never heard of an aircraft dropping a turbine to gain power for control incase of an engine failure. I know the larger aircraft have an aux. turbine but it is run off of fuel, not air.

If you read the post, he never said it was a secondary "turbine." Just sayin'.

I'm lost...

This says a second alternator drops down to produce aux power from wind. When I said turbine, I meant a device with blades shaped like airfoils that convert wind energy to electrical energy. Maybe I should have said windmill :D

Also, the air IS compressed at the front but it is so small that it is considered incompressible. When you get to Mach 0.3 is when the compressibility of air is significant enough to include it in any mathematical calculations. It should be fairly linear though.

If you placed the turbine in front of the radiator... you would be using dynamic pressure that would be impacting the vehicle anyway. That might be worth testing.... Anywhere else would be hurting you pretty bad.

How big a prop(s) would be needed to work there?

Smokey Yunick did the same thing on a race car but for a different reason: he was having a problem throwing belts. And of course going well over 100 mph he had a lot of wind to work with and also low current draw on a race car.

If you look up the story of the "Gimli Glider" the auxiliary power turbine is mentioned there.

In general, the motor is the best place to get power for a generator. However, there might be opportunities for one flapping in the wake, where things are already messed up and energized. I'm not advocating dragging a prop in the turbulence, but rather extracting energy from the sideways component of it. However, the space is probably better used for a long tail.

Thank you Bicycle Bob! I've never seen those before. I wouldn't put a large turbine in front of the radiator and you wouldn't get much out of it but it would be something for nothing ya know?

I'm addicted to this site haha. I was driving to school and remembered a MATLAB program I had written to calculate the best curvature of a turbine blade I was designing last summer.

If anyone is serious about trying to implement a turbine in front of the radiator let me know.

To ball park some figures of the power available in the oncoming air of an area 1 foot by 3 foot (3 sq. feet) guestimate...

Kinetic Energy -> E = .5mv^2 ...:: m = mass , v = velocity

Mass Flow Rate -> m/s = (rho)Av ...:: s = second , rho = density , A = area

Plug in Mass Flow Rate into Kinetic Energy for m:

E/s = (.5(rho)Av^3)/s = Power ...:: Energy per second is power.

**All following calculations are at sea level and converted to SI Units**

So 10 mph -> P = .5*(1.225)*.28*(4.48^3) = 15.4 Watts possible

30 mph -> P = .5*(1.225)*.28*(13.41^3) = 413.6 Watts possible

55 mph -> P = ...................*(24.59^3) = 2.55 kW possible

70 mph -> P = ...................*(31.29^3) = 5.25 kW possible

Pretty big jump. Lets be real and say we could get 10% of that... Catching 255 watts driving 55 mph at night might cover the headlights. Might be something worth trying. Like I said, let me know if you want me to run the AoA program and give you the curvature of the blades. I'll need a ballpark figure for how fast you want it to spool up and the alternator's efficiency so I know what kind of force is needed at that speed.

-Ryan

I realize that this is more than likely many years ahead of current technology but are there any electrical generators that generate electricity from sound energy? There would be great amounts of energy that could could be created from a car just going down the road with all the noise from the tires.

Imagine a city could generate electricity just from people doing their day to day activities.

What about generators in the struts?

What about generators in the struts?

Somebody has done that~

I had an idea for a muffler that was pan shaped that sat in the exhaust of the car and used the engine's pulsing exhaust to vibrate the mechanism and produce electricity, it would also muffle the engine. I never ran any numbers to see what could be obtained. I think I might thanks for the reminder!

But to answer the question on road noise energy? I don't believe the pressure gradient would be great enough to harness much of it. IMO not enough power to be harvested.

Actually, there isn't great amounts of energy to be had that way. ALL the sound energy produced during the entire Superbowl in Tampa was enough to heat up a cup of coffee.

do you mean the shocks or dampeners? there is energy there

Here you go:

Electric Systems

Note the Emergency Ram Air Turbine to the right of the pic.

Except that most ecomodders already significantly limit unnecessary airflow into the engine bay with partial grille blocks (as the manufacturers are beginning to do, more and more).

So it's not really something for nothing to an ecomodder. That "wasted" air has been redirected around the vehicle, so it's not available to spin a turbine of any consequence to the big picture electric needs.

totally agree with ya metro. But if you are stuck with a vehicle with a blunt front end... putting grill blocks still induces a high pressure area in the front of the vehicle... unless you wanna put a cone like that aerocivic, you're gonna have that area whether you put grill blocks or not.

No, not really...

as long as airflow is attached, the pointyness of the front end shouldn't be an issue. Think of the speeds we are going.

Well... actually, not really. The reason people talk about attached and separated flow is because of Bernoulli's Principle. Separated flow does not apply to it outside of the separated area.

It states that ..::IMPORTANT::.. in a streamline, faster flow has a lower pressure than slower flow. Here is the equation to further analyze what is happening:

P1 + .5*[rho]*V1^2 = P2 + .5*[rho]*V2^2

P1 = (static) Pressure at point one in the flow
P2 = (static) Pressure at point two in the flow

rho = density of the air (sea level density is roughly 0.0023 slugs/ft^3 english units)

V1 = velocity of air at point one
V2 = velocity of air at point two

Lets examine flow on the front of the car first. The air isn't really traveling at a certain velocity but relative to the vehicle it is. Lets say we're traveling at 102.6 ft/s (70 mph), the air in front of the vehicle does two things. In the middle of the grill, the air gets pushed on by the car and is stopped, around the sides of the grill the air gets pushed away. **Check out the FloWorks model on the main page of the colorful velocity field.. the blue means stagnant or stopped air** If the atmospheric pressure that day was roughly 2116 lbf/ft^2, plugging into Bernoulli's equation we come up with what is called a Total Pressure which amounts to:

2116 lbf/ft^2 + .5*(0.0023 slug/ft^3)*(102.6 ft/s)^2 = 2128 lbf/ft^2 + 0

As the air travels up and over the hood, it is being accelerated (ignoring the stagnant pocket at the base of the windshield). Keeping the front half of this equation, we alter the velocity from 0 where it stagnates at the grill to some value higher than 102.6 ft/s.. w/o calculating it you can see that P2 must be lower to keep both sides equal.

As flow slows down (as with attached flow over the AFT section of an airfoil or any streamlined body) the V2 value slows to close to the V1 value thus bringing P2 back to something close to P1. In a perfect world, the pressure on the back of the vehicle would be the same as the pressure in the front and there wouldn't be any drag!

Where separation comes into effect is when the air is getting decelerated too much coming around the aft section and the pressure behind the car is greater than the pressure on top of the car. Since flow goes from high to low pressure, the air doesn't want to suck down behind the vehicle and separates from the car. This 'high' pressure behind the vehicle is however, not as high as we would like and compared to the pressure on the front of the car it is low. High Pressure in the front + Low Pressure in the back = Poor Aerodynamics.

Putting a cone in the front of the vehicle minimizes the stagnant air region (Total Pressure area). This is why you see rockets, birds, even tuna with pointed front ends.

SORRY SO LONG BUT I HOPE IT HELPS!! Have a great night! :) :thumbup: :)

[QUOTE=noeryan;86775]
Putting a cone in the front of the vehicle minimizes the stagnant air region (Total Pressure area). This is why you see rockets, birds, even tuna with pointed front ends.

Rockets use pointy tops because they get into compressibility approaching Mach 1. Birds and fish are able to keep their sharp foraging implements aligned with the flow. Streamlined cars have a blunt front end, to establish the boundary layer and accommodate crosswinds. Early NACA wing sections with smaller leading edge radii were slipprier, but easier to stall.

I believe you are correct. But are you going to be driving your car at 15º AoA? I'd like to see pictures!

Haw! I'm glad nobody got pictures of some of those moments. Usually, it is the crosswinds that give me such vectors.

Oblique shockwaves form at the tip at Mach 1 and a nose cone helps minimize its intensity. HOWEVER, check out the recovery vehicles from the early Apollo missions. BLUNT front end, produced HUGE oblique shocks which: 1. gives a buffer space between the vehicle and the high heat shockwave and 2. requires a lot of energy to form thus slowing it down.

If I can find some of my data from the wind tunnels I'll show it to you. It may have been last year or the year before we placed some spherical objects in there. One was a rough sphere, a smooth sphere, a flat plate and a bowl shaped sphere facing the oncoming air and then turned away.

The rough sphere won the contest and between the spheres, the bowl shaped sphere with the concave section facing the wind came dead last.

I'm only posting to try helping if you guys think I'm wrong I won't post the forum and fill it with 'trash'. I think the best way to get through is to do testing and show numbers. I just don't have that kinda cash.

The escape rockets were just a hack for safety. The Soviets, by contrast, had really good styling on their stuff, but lost a lot of guys. The U.S. safety rockets hurt performance more than a better-integrated design would have. Even the Shuttle has to throttle back to avoid damage from the relatively thicker air at medium altitudes, and that costs fuel, too. Rocket science is not without compromises.
When seeking performance, it is important not to copy technical features too far out of context. Among the frescoes on the Parthenon, you will find fake peg-heads, as if the marble had been pegged together like the preceding wooden temples had been. To the Greeks, nothing else looked right, even if they knew it didn't matter.

Didn't know about the shuttle throttling back at low altitudes. Attached with the boosters and all its not the best shape for going supersonic IMO. Throttling back makes a lot of sense.