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Entry  Fri Aug 26 14:24:57 2022, Radhika, General, Heat Load, Mariner TM Cooldown model 6x
    Reply  Mon Aug 29 15:44:46 2022, Radhika, General, Heat Load, Mariner TM Cooldown model VaryingSnoutparams.pdfMarinerTMCooldown_snout_optimal.pdf
       Reply  Wed Sep 7 10:42:12 2022, Radhika, General, Heat Load, Mariner TM Cooldown model SnoutLengthCooldownTM.pdf
Message ID: 81     Entry time: Wed Sep 7 10:42:12 2022     In reply to: 80
Author: Radhika 
Type: General 
Category: Heat Load 
Subject: Mariner TM Cooldown model 

The attached plot (upper) compares the heat load delivered to the test mass from various snout lengths (end to end), as a function of test mass temperature. (At steady state, our point of interest is 123K.) Note that these curves use the original CAD snout radius of 5.08cm (2").

The greatest marginal reduction in heat load comes from increasing the end-to-end snout length to 1m, as concluded in the prevous ELOG. This drops the heat load from just under 0.5W (from snout length 0.5m) to 0.15W. Further increase in snout length to 1.5m drops the heat load to well under 0.1W. After this point, we get diminishing marginal benefit for increase in snout length. 

The effect on the TM cooldown curve can be seen in the lower plot. A snout length of 1m drops the steady-state TM temperature to under 100K. Then, like above, increasing the length to 1.5m makes the next non-negligible impact. 

Attachment 1: SnoutLengthCooldownTM.pdf  20 kB  Uploaded Wed Sep 7 11:56:21 2022  | Hide | Hide all
SnoutLengthCooldownTM.pdf
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