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Entry  Fri Jan 21 13:28:48 2022, Radhika, DailyProgress, Cryo vacuum chamber, Heat transfer between grease joints and pressure joints thermal_conductance_joints.png
    Reply  Fri Jan 21 17:32:40 2022, rana, DailyProgress, Cryo vacuum chamber, Heat transfer between grease joints and pressure joints 
       Reply  Tue Jan 25 10:24:14 2022, rana, DailyProgress, Cryo vacuum chamber, Heat transfer between grease joints and pressure joints 
       Reply  Tue Jan 25 13:15:40 2022, rana, DailyProgress, Cryo vacuum chamber, Heat transfer between grease joints and pressure joints 
          Reply  Tue Jan 25 14:01:27 2022, Stephen, DailyProgress, Cryo vacuum chamber, Heat transfer between grease joints and pressure joints 
             Reply  Fri Jan 28 10:31:15 2022, rana, Summary, Tutorial video, oh no, stap the units madness, aaaaahhhh!!! noooooo!!!! 
Message ID: 2711     Entry time: Tue Jan 25 10:24:14 2022     In reply to: 2710
Author: rana 
Type: DailyProgress 
Category: Cryo vacuum chamber 
Subject: Heat transfer between grease joints and pressure joints 

For one surface resting on another, the force of the contact is the grativational force of the top surface. There's an implicit factor of g that cancels out from the ratio, so it becomes a ratio of masses. The heat conductance listed for a 50 kg Al-Al pressure joint is interpreted as the heat conductance for a force of 50g.

Quote:

Is there a units issue? 50 kg is a mass, but not a force.

 

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