STEORN DEMO LIVE & STREAM in Dublin, December 15th, 10 AM

[broli]

People really think Steorn has been doing nothing these past years. Don't you think if they are selling those torque integrators they would have used them themselves to death???

They know exactly how much energy is generated and used without the use of speculation or simulations. Further more this allows them to perfect the system in almost record times. By changing angles and materials on the spot. Then people like tinselkoala come along disproving their entire data by eye balling and speculation, this is outrageous to say the least. I have nothing against debunking but if that's your goal you better set the standards much higher than the thing you want to debunk not LOWER!

I have ran my own simulations to see how much net flux a magnet creates in a toroid when it passes it by and it's very little but definitely not zero. Determining this is not straightforward as you require a double integral which FEMM might be able to do.

This simulation has nothing to do with the forces but purely on the amount of "functional" flux caused by the magnet in the CORE that is able to cause a counter EMF. What I mean by functional is that you only look at the flux portion that goes tangential with the toroid and since this is the only portion that will induce an emf.

The integral has to be made in concentric circles around the core going from inner diamater to outer diameter. This will give a value that can be attributed to the net flux. If you animate this with the magnet starting at TDC and moving away from the core you will need to do this integral every frame.

There's a trick to completely kill emf without the need of simulations and speculation. I'll think about it more and post it.

[PaulLowrance]

FEMM gives forces as well.

BTW, FEMM cannot sim the Orbo design because it requires 3D sim beyond axisymmetric. FEMM can only do 3D axisymmetric sims.

[broli]

It depends, if the polarity is as the below illustration then it can. But such simulation is definitely not for the faint of heart. You need to be sure of what you are doing.

you start at 10 o'clock for instance and start measuring torque up until 6 o'clock. Then you switch on the coil and you keep measuring torque. When you hit about 8 o'clock you switch the coil off while still measuring torque until you reach 12 o'clock once again.

This is the "easy" part. The near impossible part is measuring counter emf during the 6 to 8 o'clock portion. and getting a meaningful energy comparison.

[PaulLowrance]

broli,

In FEMM all of those parts are *infinitely* high, and therefore the magnetic field is prevented from escaping on a axis that would go outside the screen. Also the magnetic field from the magnet is going to be less. Furthermore the effective permeability from an infinitely high toroid for *external* fields is going to be completely different than if it was done properly in a 3D sim.

[k4zep]

[continued]
Ben makes an interesting point about the mechanical switch in Orbo. It's true there are transistors with incredibly low resistance, but one thing I've always hated about designing such circuits is that they require a diode, and diodes have a forward voltage. One way to improve the efficiency of a solid state design is to bring the voltage levels as high as possible, so the if diode forward voltage is say 0.5V, and caps voltage is 500V, then the losses are not so bad. I know there are a high speed relays, and there's not forward voltage drop like a diode. Maybe that's why Steorn used a relay instead.

A continuation on that thought is even at low voltages, the rise time of a good power HEXFET is very fast so very low loss there, then if the capture diodes across the coil is fast enough, they turn on @ around .7V/diode and FET is not damaged plus as soon as they turn on, it is a current source returning power to the battery.  Remember that inductive/BEMF pulse is very high voltage if not switched into battery.  Been experimenting with somee 2.7 V, 650FULTRACAP's this morning and they are amazing devices.....Impedance is so low it is unbelieveable! Low leakage, robust. Just looks like the ultimate power source!  Sure would like to see one on their device!  Going to build a motor but will have to wait till this weekend, traveling over Xmas, back on Sat.