Solve the Flywheel-IVT Problem with This Simple Solution in 15 Seconds

[rcgldr]

In my previous post, I was mixing up a convention belt type CVT with IVT, but the basic issue of mismatched torques and non-conserved angular momentum still applies. Without some energy storing device involved, momentum and/or energy will not be preserved.

Using flywheels to store energy for vehicles has been done before, but I'm not sure if these included drawing energy from braking to add energy back to the flywheels. Most of the braking energy recovery systems rely on generation of electricity, and capacitors or batteries seem like they would be more efficient than flywheels for this purpose.

 

[Cleonis]

Using flywheels to store energy for vehicles has been done before, but I'm not sure if these included drawing energy from braking to add energy back to the flywheels. Most of the braking energy recovery systems rely on generation of electricity, and capacitors or batteries seem like they would be more efficient than flywheels for this purpose.

Actually, it is my understanding that an electric system has a lower performance than a mechanical system. (For the case where both types are pushed to engineering optimum.)

When generating electric energy there are always eddy currents. The problem of eddy currents can be mitigated, but not entirely removed. Likewise for electric energy to motion. So you lose energy in both directions.

Kinetic energy can be transferred to and from a flywheel with very little loss.
As to the flywheel itself: if the flywheel's encasing contains air at atmospheric pressure then there is a lot of friction that causes loss of energy. So the pressure in the encasing is reduced, making it close to vacuum. Of course that makes the engineering very difficult.

That is, to my understanding, why mechanical regenerative braking will outperform electrical regenerative braking (but the mechanical system is probably too expensive to be viable.)

 

[jimgram]

Most of the braking energy recovery systems rely on generation of electricity, and capacitors or batteries seem like they would be more efficient than flywheels for this purpose.

I'm quite familiar with ultracapacitors working as a consultant for Preco, Inc. and Maxwell. You bring up a very significant point, but in fact the energy density of flywheels is in the order of 6-100 Wh/m³ while ultracaps is only 0.8-4 Wh/m³. Lithium-Ion batteries are approximately 80-200 Wh/kg.

Ultracaps are exceptional in regards to peak power being 5-1000 kW: However for a flywheel, power density can be 0.3-40 MW/m³ while ultracaps range between 0.3-1 MW/m³.

Batteries cannot absorb energy fast enough for braking energy recovery. Flywheels, given an efficient IVT with adequate torque capability far surpass both batteries and ultracaps.

This is probably why since the 50's so much R & D has gone to flywheel systems, yet to date no adequate solution to the IVT problem has been found. Torotek is close but its limited torque capabiltiy means it cannot be applied in the most needed applications: large commerical vehicles such as refuse trucks, school bus's, delivery vehicles, etc.

 

[RonL]

Regen straight to a large flywheel, goes back to the 50's and 60's and maybe further.

Stored energy using counter rotating flywheels, compression and expansion of air, the dual application of EMF and CEMF, can almost eliminate the need for batteries and capacitors.

Run the numbers using counter rotation flywheels 5,000 RPM each, large energy and zero torque, high voltage and zero current. Applying current load will draw down one flywheel while motive force speeds the other. Closeness of cycle rate (assume 4500 and 5500) can be nano, micro, seconds, or depending on flywheel mass, minutes.
A gas cycle brings heat absorption into play, the one thing electric cannot do. This gives at least, a method of recovery of waste heat.

It's all there, but more than I can bite off or do the math on.

Ron

 

[jimgram]

RonL: You just described our second generation 2-flywheel system. Exactly on target. If you search some of my previous posts you'll see how long I have been attempting to nail the mathematical analysis.

Kinetic power LLC has developed such a system (built and working) utilizing 2 variable-inertia flywheels, each coupled to a motor-generator as well as the epicyclic differential. My goal has been the performance modeling. My background is electronic engineering and obviuosly have been struggling with the math concepts, however with the recent inputs from this forum I believe I'm much closer to an understanding of what is happening. Thanks to all!

 

[RonL]

RonL: You just described our second generation 2-flywheel system. Exactly on target. If you search some of my previous posts you'll see how long I have been attempting to nail the mathematical analysis.

Kinetic power LLC has developed such a system (built and working) utilizing 2 variable-inertia flywheels, each coupled to a motor-generator as well as the epicyclic differential. My goal has been the performance modeling. My background is electronic engineering and obviuosly have been struggling with the math concepts, however with the recent inputs from this forum I believe I'm much closer to an understanding of what is happening. Thanks to all!

Thanks jimgram, that positive comment came at a really good time. :)

I will look at your post and for the company website.

Ron

 

[RonL]

RonL: You just described our second generation 2-flywheel system. Exactly on target. If you search some of my previous posts you'll see how long I have been attempting to nail the mathematical analysis.

Kinetic power LLC has developed such a system (built and working) utilizing 2 variable-inertia flywheels, each coupled to a motor-generator as well as the epicyclic differential. My goal has been the performance modeling. My background is electronic engineering and obviuosly have been struggling with the math concepts, however with the recent inputs from this forum I believe I'm much closer to an understanding of what is happening. Thanks to all!

I have looked at all your threads and post's in them, it seemed that in post #10 of "conservation of angular momentum" the full impact of just how much energy is in store became clear in your mind.
The name Kinetic Power, LLC. did not turn up anything that seemed to go along with this topic, do you have anything more, or did I get too close to the patent in process that is being worked on ?

Ron

 

[jimgram]

RonL:
Actually, our patent application was recently published so we will be bringing our website up soon - as of now you are correct - there is no public info available. You are also correct about the understanding of angular momentum - I needed to visualize the whole system in the absence of earth-based physics (I.E. in space). It's still a problem however: I see that torque is applied to the gear housing and that dL/t = torque. L is I*\omega, so, it doen't matter how you assume I or \omega for the conservation of momentum, but matters significantly with regard to the conservation of energy.

 

[RonL]

RonL:
Actually, our patent application was recently published so we will be bringing our website up soon - as of now you are correct - there is no public info available. You are also correct about the understanding of angular momentum - I needed to visualize the whole system in the absence of earth-based physics (I.E. in space). It's still a problem however: I see that torque is applied to the gear housing and that dL/t = torque. L is I*\omega, so, it doen't matter how you assume I or \omega for the conservation of momentum, but matters significantly with regard to the conservation of energy.

Thanks, I will be looking forward to a web site.

I have gone through the thread again, I'm a little embarrased that my post seems to parrot your post #30. I don't understand the math of the pdf in post#13, but I think I understand the problem.
I would like to throw out one of my observations from years of thought processing (and some actual bench testing) based on counter rotating flywheels, when the physical mechanical contact for energy exchange is removed you will find the efficiency to improve by a great amount.

A question about what I think is going on, and what I think most people fail to consider, or just overlook, would be...If power is added for an amount of time that brings a flywheel to it's maximum rpm, the kinetic energy has grown far in excess of the power used to bring it to that point, is this correct ?

It seems that most rebuttals to flywheel energy storage is, a cycle expressed as zero to max, and then max to zero, which will of course leave an overall loss every time. Cycle time at peak rpm is the most important thing.

So to me the total energy exchange between two interacting flywheels, if using only gas pressure and electromagnetic transfer, will result in the most efficiency possible.

The perfect system, as I have in mind, can come with a NDA and the price might be far cheaper than you would expect.

Jim, thanks for your threads.

Ron