Recent content by Rework

So can I conclude that you get back what you put in, whether it is air or steel? Apparently no one can explain in simple terms what is happening when you tickle iron with a small H field and get a large B magnetic field. Please excuse my BSME.

This is a statement from "milesyoung" in the 2013 thread: Think of it this way, it takes less effort (work) to increase the magnitude of B in a steel core solenoid than in an air core solenoid, so for the same magnitude of B, less potential energy is stored. This is a statement from...

Correct. So what I am not understanding is that apparently, even though the current is the same, it takes more energy in the case of steel, to get to full current. The B field is greater, and contains more energy when collapsing, so you get the energy back. So even though the amp-turns "H" are...

I thought it takes less H to get the same B with the steel core? B=MU X H

https://www.physicsforums.com/threads/magnetic-energy-of-solenoid-with-without-core.692789/

Hi - On this forum, dgreenheck on May 20, 2013 touched on this area. I will post my question in this manner: Say one has a solenoid with a given number of turns; if the core is air, we know that if we run 10 amps through the circuit, the energy to charge a magnetic field to "B" Tesla is...

BTY, what is the best place on this site to discuss superconductors, etc?

There is a post on your "Classical Physics" forum, dated May 20, 2013, discussing stored energy. If that is correct thinking, and I understood it,that would also answer my question. I need to learn all I can about SMES. They will get more popular. Thanks for all your help.

Being an ME, we had to learn EE in one year, so am a bit short on my theory. But am still having a problem. It appears you are getting something for nothing; with the same H, you are getting more B when you have a steel core vs air.

http://www.superpower-inc.com/content/superconducting-magnetic-energy-storage-smes So as in this web page, they take short makeable magnets and arrange them in a circle to form a toroid, which keeps most of the field within the toroid.

https://en.wikipedia.org/wiki/Superconducting_magnetic_energy_storage

Superconductor Magnetic Energy Storage

My reason for the question is involving a SMES. As far as I know, the current SMES construction is with an air core. not steel or mumetal. Is that for a reason?

So going back to my original post, I say the amp turns are the same; the turns are always the same obviously, but in the case of the steel core, the amps will increase. Is that a true statement?

OK -- I'm going in circles here! The stored energy increases with the inductance, and the inductance increases with mu. I understand that. What I don't understand is what happens, say, if you have an air-core solenoid that is fully charged (steady current, no inductance at that point) and you...