Frost-free window
Frost-free window
(OP)
I need to keep a window (300mm x 125mm) in an environmental chamber free from frost at temperatures down to -180°C.
The window is formed from 4 separate panes, since the window must also withstand 600°C.
I can keep inter-pane space clear by purging with dry gas, but outer pane in contact with ambient air always fogs. Using tin-coated glass("K-glass"), and passing current across it, OK for some applications, but electrical connections fry after prolonged high temperature running. Also currents and voltages necessary are kind of high for areas that can be touched by fingers!
The window is formed from 4 separate panes, since the window must also withstand 600°C.
I can keep inter-pane space clear by purging with dry gas, but outer pane in contact with ambient air always fogs. Using tin-coated glass("K-glass"), and passing current across it, OK for some applications, but electrical connections fry after prolonged high temperature running. Also currents and voltages necessary are kind of high for areas that can be touched by fingers!





RE: Frost-free window
RE: Frost-free window
-180C to + 600C.... this is an exceptional and odd temp range... especially for an uncontroled environment [obviously humidity is a factor]. Must be testing aerospace materials.
Suggest You purge the chamber with dry nitrogen for several minutes before starting; then insure a positive pressure bleed-out of dry nitrogen from the chamber through-out the test.
Regards, Wil Taylor
Regards, Wil Taylor
RE: Frost-free window