120 likes | 206 Views
A Proposed Layout for Light-Sealing around the Focal Plane. Robert Besuner 17 April 2005. Some notes. Desire is to replace two or three labyrinths with one. Labyrinths replaced: cone/OTA, cone/FP, maybe FP/aft of FP. Replace those with one light seal from radiator to OTA.
E N D
A Proposed Layout for Light-Sealing around the Focal Plane Robert Besuner 17 April 2005
Some notes • Desire is to replace two or three labyrinths with one. • Labyrinths replaced: cone/OTA, cone/FP, maybe FP/aft of FP. • Replace those with one light seal from radiator to OTA. • Could substitute word ‘labyrinth’ with ‘bellows’ or anything light-tight with minimal thermal and mechanical coupling between the two sides. • Relative motions between radiator and OTA in vibe may be large...labyrinth clearances here are 20mm. • Thermal coupling across labyrinth could be sizeable. One possibility is to make light seal thermally insulation. If G-10 fiberglass, something like a watt might flow from OTA to radiator (That’s pure conduction, no rad. analysis at labyrinth).
cone being withdrawn, note mounting ring that stays with bipods, which stay with bench
section showing possible heat strap paths • violet-straight to cover, heat flows from cover to rest of radiator • blue-straight to (conducting) light seal, heat flows to main radiator and cover • green-thru light seal (thru labyrinth?, thru more strap terminations?), then to radiator • Also, note gap between cone and cold plate...no labyrinth