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Entry  Fri Sep 24 13:12:00 2021, Radhika, General, Heat Load, Mariner cooldown model status + next steps 
    Reply  Mon Sep 27 17:01:53 2021, rana, General, Heat Load, Mariner cooldown model status + next steps 
       Reply  Wed Sep 29 16:15:19 2021, Radhika, General, Heat Load, Mariner cooldown model status + next steps Heat_Load_Sketch_geometry.pdfHeat_Load_Sketch_diagram.pdfheating_cooling_P_vs_T.pdfCooldownTM_radiative.pdf
          Reply  Tue Oct 5 17:46:14 2021, Radhika, General, Heat Load, Mariner cooldown model status + next steps Heat_Load_Sketch_all.pdfVaryingISA.pdfCooldownTM.pdf
             Reply  Fri Oct 15 13:45:55 2021, Radhika, General, Heat Load, Mariner cooldown model status + next steps VaryingTMl.pdf
                Reply  Fri Oct 15 14:31:15 2021, Radhika, General, Heat Load, Mariner cooldown model status + next steps VaryingISA.pdfVaryingTMl.pdf
Message ID: 43     Entry time: Fri Oct 15 14:31:15 2021     In reply to: 42
Author: Radhika 
Type: General 
Category: Heat Load 
Subject: Mariner cooldown model status + next steps 

I reran the cooldown model, setting the emissivity of the inner surface of the inner shield to 0.7 (coating), and the emissivity of the outer surface to 0.03 (polished Al). Previously, the value for both surfaces was set to 0.3 (rough aluminum). 

Attachment 1: TM cooldown, varying area of the inner shield. Now, the marginal improvement in cooldown once the IS area reaches 0.22 m2 is negligible. Cooldown time to 123K is ~100 hrs, just over 4 days. I've kept IS area set to 0.22 m2 moving forward.

Attachment 2: TM/IS cooldown, considering 2 lengths for the test mass. Choosing l=100m instead of 150mm increases cooldown time from ~100 hrs to ~145 hrs, or 6 days.

Attachment 1: VaryingISA.pdf  20 kB  Uploaded Fri Oct 15 15:34:06 2021  | Hide | Hide all
VaryingISA.pdf
Attachment 2: VaryingTMl.pdf  19 kB  Uploaded Fri Oct 15 15:34:16 2021  | Hide | Hide all
VaryingTMl.pdf
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