Cryogenic Insulation for Superconducting Transformer Project

[mitsi_man]

I was hoping there is somewhere on here that can help
Im working on a project designing a superconducting transformer
currently i have to report possible options to use. Does anyone have any experience with cryogenic insulation if so what can you recomend.
It looks like glass microspheres or pearlite in a vacuum is going to be the best option.
also there is aerogel but I am having trouble finding a supplier, we are trying to stay away from MLI as the aluminium will induce eddy currents...
So What I am asking is does anyone have information on cost or sourcing these materials or another alteranatives?

 

[Q_Goest]

What temperature are you trying to maintain?

If the aluminum causes eddy currents, then aren't stainless steel walls also going to be an issue? I'm assuming the insulation is going to be vacuum insulation, and you're just asking about what to put inside that vacuum. Needless to say, MLI is the best option for that but you need to be able to pull a vacuum.

 

[lamba89]

expanded foams
gas-filled poweders and fibrous materials
vacuum alone
evacuated powders and fibrous materials
opacified poweders
multilayer insulation

those are some of the main insulation options listed in order of increasing performance and increasing cost. not sure about cost or sourcing

 

[mitsi_man]

77 K temperature, it will be made of g10 composite and will have a vacuum,
we are trying to minimize the heat loss as much as possible as it takes about 30 times the energy to cool every watt when using cryopumps at that temperature.
ive also seen LCI layered composite insulation on the net from NASA.
it looks like it will be a choice of powder or mli.