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Flywheel Question

09/10/2014 7:54 AM

https://www.youtube.com/watch?v=7ZCrcyeGhRw
Greetings, I found this flywheel configuration and I was so fascinated by it that I fabricated one. I am puzzled as to why it works at higher RPMs and not at lower RPMs.Any help will be greatly appreciated.
I was just having some fun with video name, I do not know what to call it. Suggestion welcome.

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#1

Re: Flywheel question

09/10/2014 8:07 AM

This is another communication and comprehension problem because this amusing device appears to me to work as expected. Why do you think that it doesn't work at low RPM?

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#2

Re: Flywheel question

09/10/2014 8:22 AM

What's fascinating about this? It's a clunky, poorly designed flywheel....Now if you want something truly fascinating, check this out....

Although I don't think you will be able to build one....

..."150 watt hours of energy can be captured in only 8 seconds, and the energy can be stored for up to 30 minutes or used immediately. The KERS system - which spins its flywheel at a maximum of 60,000 rpm in a true vacuum and can deliver 80hp -- can be used to knock 1.5 seconds off the car's 0-60 time or in an economy mode to reduce pollution. The entire system only weighs about 130 pounds, which makes it much lighter than a traditional electric motor and NiMH/Li-ion battery packs used in hybrid vehicles. For example, the batteries alone used in Volvo's current hybrids weigh 660 pounds. "...

http://www.dailytech.com/Volvo+Flybrid+KERS+System+Promises+to+Reduce+Fuel+Consumption+by+25/article34591.htm

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#3
In reply to #2

Re: Flywheel question

09/10/2014 9:26 AM

My uncle was an auto mechanic who retired in the '70s. He told me of a car that had been modified with an oversize flywheel and a ratchet mechanism. This allowed the engine to down rev without dragging on the car and slowing it down. If I recall, it was a modification of a stock transmission. This was done in the late '50s or early '60s.

It was abandoned when they realized that one couldn't downshift to slow the car in an emergency. Essentially, it was deemed unsafe. My uncle did say that it got great fuel mileage.

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#8
In reply to #3

Re: Flywheel question

09/10/2014 12:19 PM

Yeah the problem with that is you're using the engine rev's to power the flywheel, this is going to add to the drag on the engine just like adding several hundred lbs...now on the other hand the braking is lost energy, if you can recapture a good part of this energy, well then you can see this will add to the efficiency of the vehicle...The other side of the coin is dropping weight and increasing aerodynamics....

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#11
In reply to #8

Re: Flywheel question

09/10/2014 1:24 PM

isn't that called something like regenerated braking?

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#14
In reply to #11

Re: Flywheel question

09/10/2014 2:11 PM

....regurgitated baking....?

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#5
In reply to #2

Re: Flywheel question

09/10/2014 11:33 AM

Hopefully that thing is gimballed if you want to do anything but straight and level or there might be some interesting gyroscopic reaction. In the case of an accident, I can imagine a whole new meaning to the phrase "taking it for a spin" since the angular momentum has to go somewhere!

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#6
In reply to #2

Re: Flywheel question

09/10/2014 11:54 AM

What's "vaccum"?

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#9
In reply to #6

Re: Flywheel question

09/10/2014 12:27 PM

vacuum in Swedish....?

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#15
In reply to #6

Re: Flywheel question

09/10/2014 3:31 PM

It's what lets a flywhhel go around longer.

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#13
In reply to #2

Re: Flywheel question

09/10/2014 1:43 PM

SUNDAY! at beautiful US route 30 dragstrip See the turbo powered VW..INCREADABLE!

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#16
In reply to #13

Re: Flywheel question

09/11/2014 12:22 AM

Hey, thanks for the add. I must have seen that add a thousand times. It still looks like a modification to a Hillibrand Quick Change.

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#17
In reply to #13

Re: Flywheel question

09/11/2014 3:21 AM

I have read about them, but never seen a picture....Thanks.

I believe the "Land-Trains" in Australia also use them once they are out of the cities....its cheaper fuel for long distances with no stopping!

I looked around but could not confirm that....

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#18
In reply to #17

Re: Flywheel question

09/11/2014 8:57 AM

"Instantaneous torque" was a claim made, and by what I saw in performance from a VW bug and a go-kart, the claim was pretty close. Some units I saw were bolt-ups to the stock differential with the drive pinion engaging the ring gear.

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#19
In reply to #2

Re: Flywheel question

09/11/2014 9:32 AM

I remember something of this sort from back in the 1990's.

It was designed by a guy named Ballard?,I think.

I may have the name wrong,though?

He used cheaper materials in the center of the flywheel,and progressively stronger as the diameter increased.

He and his son developed a program to determine the best materials and locations within the flywheel for each.

There were used in pairs in vehicle, spinning in opposite directions, offsetting the gyro effects.

The problem at the time, as I recall was the energy required of maintaining a dynamic electromagnetic bearing, that would adjust for impact loading and road vibration.

There were no permanent magnets at the time that could do the job without electromagnetic assistance.

Much progress has been made in magnets since then, so it is possible they now use a permanent magnet without the need for electrical assistance.

They were,and possibly still are, used for back up power in hospitals and large critical institutions,and power grids for load balancing.

They were to be buried vertically in concrete for safety in case these massive flywheels were to disintegrate.

Supporting a stationary flywheel was no problem.

The output motor becomes an alternator in charge mode,so it is ideal for dynamic braking.

This is especially efficient in stop and go urban traffic.

Some city buses use flywheel storage for this very reason.

Going even further back to the 1970's a couple of engineers coupled a V8 Ford engine to a hydraulic pump,and the pump was used to store hydraulic pressure in a spherical reservoir tank, which in turn was used to power a hydraulic motor/pump for the drive wheels.When decelerating the motor functioned as a pump,recharging the reservoir.

The motor was disengaged when not needed by a computer (Which was quite bulky in those days),triggered by a pressure switch on the reservoir.

The motor was restarted via hydraulic pressure instead of an electric starter.

The system was built using ready made off the shelf components, and the cost was less than an automatic transmission.

However,politics prevails over common sense,and the idea never took off.

As it was then ,so it is today.

As a Roman philosopher once said:

"We hang the petty thieves,and elect the great ones!"

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#4

Re: Flywheel Question

09/10/2014 10:04 AM
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#7
In reply to #4

Re: Flywheel Question

09/10/2014 12:16 PM

Hi, I found a video showing conservation of angular momentum and the force from a gyroscope that explains why the device spins but I am trying figure out what force is making it accelerate and what is creating that force when the support arms are at a higher RPM?

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#10
In reply to #7

Re: Flywheel Question

09/10/2014 12:40 PM

Now I think I understand what is baffling you.

The two outer discs/gears have a significant added mass attached. When these masses move closer to the axis of rotation, stored rotational energy and inertia is released to the whole mechanism and it spins faster. Similarly when these masses move away from the axis of rotation they take and store rotational energy and momentum from the whole machine making it slower. The classic demonstration of the athletic ice skater that starts a spin in a squatting position with as much of their body as possible (withou falling) away from the slow initial spinning axis. As they gracefully pull their body parts closer to the axis of spin they speed up.

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#12
In reply to #4

Re: Flywheel Question

09/10/2014 1:26 PM

a more precise term is gyroscopic inertia

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#20
In reply to #12

Re: Flywheel Question

09/22/2014 8:49 AM

https://www.youtube.com/watch?v=W59ROq45d_s

The above configuration had no benefit.

Hi, project update.
https://www.youtube.com/watch?v=fp3-UDY7VNM&feature=gp-n-y&google_comment_id=z12ku1trbtjtinm4x04chpwqxvrkth44x5o

If you have a 1 HP motor how do you determine the correct size of the flywheel? Comments, suggestions welcome

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#21
In reply to #20

Re: Flywheel Question

09/22/2014 9:16 AM

http://nptel.ac.in/courses/IIT-MADRAS/Machine_Design_II/pdf/3_7.pdf
It looks like I found what I was looking for. Cheers

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