40m
QIL
Cryo_Lab
CTN
SUS_Lab
TCS_Lab
OMC_Lab
CRIME_Lab
FEA
ENG_Labs
OptContFac
Mariner
WBEEShop
|
COMSOL elog |
Not logged in |
 |
|
|
Message ID: 130
Entry time: Sun Aug 26 19:21:27 2018
In reply to: 109
|
Author: |
rana |
Type: |
General |
Category: |
Voyager |
Subject: |
Voyager ITM: Radiative cooling with cold shield and cold CP |
|
|
this is a time dependent model of the previous steady-state one
- Cold Shield and CP held at a constant 60 K
- 3 W heat input to the ITM from the main laser beam
- radiative cooling to the shield
- ITM barrel emissivity = 0.9
- ITM HR/AR emissivity = 0.5/0.5
So the cooldown time w/o a heat switch is ~4 days. Since this is less than the usual pumpdown time required to open the gate valves on the beamtubes, perhaps no heatswitch or in-vac cryogens are required. |
|
|
Attachment 2: |
CoolDown.webm
169 kB
Uploaded Sun Aug 26 21:16:14 2018
| |