Timeline for Relation between air-core and ferromagnetic solenoid -core magnetorquers and measurement of dipole moment
Current License: CC BY-SA 3.0
23 events
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| Apr 13, 2017 at 12:58 | history | edited | CommunityBot |
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| Feb 13, 2017 at 19:46 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Jan 18, 2017 at 0:30 | history | tweeted | twitter.com/StackSpaceExp/status/821515173345263616 | ||
| Jan 14, 2017 at 19:29 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Dec 15, 2016 at 18:38 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Nov 15, 2016 at 18:06 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Oct 16, 2016 at 17:06 | history | edited | John | CC BY-SA 3.0 |
Included more details
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| Oct 16, 2016 at 17:01 | answer | added | Adam Wuerl | timeline score: 1 | |
| Oct 16, 2016 at 12:04 | history | edited | John | CC BY-SA 3.0 |
I realized that it should be air-core magnetorquers instead of air coil. It makes more sense that way since the only difference between the two types is the material used for the core
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| Oct 16, 2016 at 5:04 | comment | added | John | Ah, alright. I'll edit my question to make it more concise | |
| Oct 16, 2016 at 4:32 | comment | added | uhoh | This is stackexchange, it works so well because it is structured. Maybe you see the message Please avoid extended discussions in comments. appearing? It needs some patience, and some care to write your questions carefully. | |
| Oct 16, 2016 at 4:05 | comment | added | John | I think it's still relevant isn't it? In the post I've asked how to measure the dipole moment. So inquiring about how to set up the air coil to measure the dipole accurately would still be coherent right? | |
| Oct 16, 2016 at 4:02 | comment | added | uhoh | In stackexchange, it is best to stick to asking questions as posted questions, and not to have too many at the same time. It's not perfect but it's the way things work here. | |
| Oct 16, 2016 at 2:11 | comment | added | John | Ah, I've actually found this link : info.ee.surrey.ac.uk/Workshop/advice/coils/air_coils.html#FDS referring to this link, should I orientated my setup in the same way? In other words prop my solar panel a up and measure the b field at distance X from the center of the coil? | |
| Oct 16, 2016 at 1:50 | comment | added | uhoh | You can use the equation in your previous question and my answer. Since you are measuring an air core coil in air, just use $B=\mu_0H$ with $\mu_0=4\pi \times 10^{-7}$ - the permeability of free space. | |
| Oct 16, 2016 at 1:45 | comment | added | John | Sorry if I'm asking so many questions, I'm really trying to understand it. And of course to solve my problem. | |
| Oct 16, 2016 at 1:45 | comment | added | John | By that you mean measuring the b field at the large distance away from the coil? Wouldn't that be the same as using biot savarts law? Even if I can obtain the B field, how would I calculate the magnetic moment from it? I only have a magnetometer to measure the b field. | |
| Oct 16, 2016 at 1:41 | comment | added | uhoh | So again the best way is to measure at large distance where you can call it a point dipole. | |
| Oct 16, 2016 at 1:41 | comment | added | uhoh | No you definitely can't use that equation. It is a (fairly good) approximation for a uniformly magnetized rod of ferromagnetic material, with a permeability $/mu$. The detailed shape of the coil isn't even specified there - it assumes the coil magnetizes the permeable material uniformly. Here you have only a coil and no permeable material. You need math that applies to a flat coil in air. It will also have to be an approximation because this coil has multiple turns of different sizes, and their shape isn't even a perfect square. | |
| Oct 16, 2016 at 1:29 | comment | added | John | Yeah, I tried using m=nIA to calculate n, the number of turns, and found that it is indeed 1. The datasheet specifies the max m at the max voltage. But in terms of measuring the actual m, would it be already to think of my air coil as a ferromagnetic rod that is pressed flat, and use the same paper that I linked to find m? | |
| Oct 16, 2016 at 1:26 | comment | added | uhoh | That's a very nice paper about the ferromagnetic rod magnetotorquer testing. I don't think that that the equation $m=nIA$ applies to a ferromagnetic rod - there's no place to but the permeability or dimensions of the rod. However I think is a good equation to use for your flat coil. I believe that the spec of 1.55$m^2$ in the data sheet represents the product $nA$. If the area of one turn of the PCB trace is roughly 9x9 cm${}^2$ then there are roughy 150 to 200 very narrow turns in the trace, which explains the high DC resistance. | |
| Oct 15, 2016 at 23:14 | history | edited | Adam Wuerl | CC BY-SA 3.0 |
fixed LaTeX
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| Oct 15, 2016 at 13:50 | history | asked | John | CC BY-SA 3.0 |