RE: 130kW Coil Update [helium gap]
From: Greg Leyh[SMTP:lod-at-pacbell-dot-net]
Sent: Wednesday, December 10, 1997 3:40 PM
To: Tesla List
Subject: Re: 130kW Coil Update
Edward V. Phillips wrote:
> "The 30HP, 500VDC Westinghouse motor seems to have no problem with
> this, however. Cursed aero drag = v^3!"
> Have you considered running it in helium? Would cut the
> windage significantly and help with cooling. Don't know what
> the effect would be on gap breakdown.
Alas, the gap is of the open frame type, far from airtight.
As I understand it, helium actually has a lower heat capacity,
since monatomic elements only have 5 degrees of freedom,
where diatomic ones have 7, allowing them to carry more heat
energy per deg C. That's why He compressors run so hot.
At STP, I believe that helium gas has a much lower breakdown
voltage than dry N2. But is this good or bad?