TOTEM Collaboration Meeti ng, Feb. 2005, F. Haug, CERN Cooling System for TOTEM Friedrich Haug and Jihao Wu Cryogenics for Experiments CERN TOTEM Collaboration Meeting Feb. 2005
Dec 24, 2015
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
Cooling System for TOTEM
Friedrich Haugand
Jihao WuCryogenics for Experiments
CERN
TOTEM Collaboration Meeting Feb. 2005
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
Subjects discussed
• Temporary Cooling Solution for X5 and SPS in 2004
• Basic Design Principle and Lay-out for LHC• Key Technologies Heat Pipes and Pulse Tube
Refrigeration• Design and Development • Results and Outlook for 2005
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
Temporary Cooling Solution for SPS and X5 Experiments in 2004
The temporary cooling solution for the experiments at SPS and at X5 beam consisted of using liquid nitrogen as cold source withdrawn from mobile dewars, distributed and fed in parallel to the heat exchangers inside the Roman Pots. A connecting flexible thermal bridge provided extraction of the dissipated heat in the RP set-up which was cooled. The temperature was controlled with a local electric heater and a limited control loop.
LN2 Lines
Heat exchanger
El. Heater (not visible) Flexible
thermal connection
Roman Pot Insert during Assembly Phase
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
Simplified Schedule
• 2004: First TOTEM Beam Experiments and Tests + Simple Cooling . Results: Cooling principle = versatile and useful for the purpose. Not applicable for final installation at LHC.
• 2005: Development Phase of Cooling System and Components
• 2006: Construction Phase
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
Heat pipe 1 Adiabatic zone
Refrigerator cold head
Pulse tube refrigerator
Interconnecting block Cryostat
Beam centre line
Horizontal roman pot
Vertical roman pots
Heat pipe 2
Heat pipe 3
Basic Cooling Design Principle for LHC
The dissipated heat from the six RP’s is conducted by six individual heat pipes to a central cryostat housing the Pulse Tube Refigerator.
-Heat Pipes are passive, effective heat transfer elements.
-Pulse Tube Refrigerators are modern cryogen free coolers exhibiting low vibration noise.
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
HEAT PIPE
-A heat pipe is a completely passive heat transfer device without any moving mechanical parts like e.g. circulation pumps.
-It shows an extremely high effective thermal conductivity in using the high heat of vaporization (condensation) of a two-phase working fluid.
-Its principle relies on a continuous evaporation / condensation process and the heat transfer is done via mass transfer of counterflowing vapor and condensate.
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
Heat Pipe Cross Section (Example)
Vapor duct
Longitudinal Capillaries for liquid return
Courtesy
IKE, University Stuttgart Mesh
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
QRL Transfer Line for LHC collider magnets
Refrigerator Compressor(can also be installed at distance)
Vertical and horizontal Roman Pot Units
Beam vacuum pipes
Heat Pipes
Pulse Tube Refrigerator integrated in Cryostat
Proposed Layout at LHC with Heat Pipes and Pulse Tube Refrigerator
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
Investigation of an “Ambient” Temperature Heat Pipe Operating at different angles (gravity-assist to antigravity)
0
10
20
30
40
50
60
290 300 310 320 330 340 350 360
temp in K
Po
wre
r in
W
angle=0
angle=90
angle=180
angle=30
angle=120
The results show the measured performance limits at different inclination angles and temperatures. Operation against gravity reduces the heat transfer capacity by an important factor.
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
Laboratory Set-up for Performance Measurements of Heat Pipes with Pulse Tube Refrigeration (from ambient temperature to 100 K)
Pulse tube refrigerator
Vacuum enclosure
(inside Heat Pipe)
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
Performance Characteristics of the Pulse Tube Refrigerator (without Heat Pipes) at different Inclination Angles
0
20
40
60
80
100
120
140
160
0 50 100 150 200 250 300
Temp.in K
Po
we
r in
W
gravity assisted
horizontal
antigravity
TOTEM Collaboration Meeting, Feb. 2005, F. Haug, CERN
RESULTS TO DATE-X5, SPS tests successfully completed-Preliminary results of ambient temperature heat pipes (gravity assist and anti-gravity operation) = encouraging-Laboratory set-up with Pulse Tube Refrigeration = operational-Investigations on cryogenic heat pipes has started
OUTLOOK for 2005-Thermal Model of a Roman Pot Insert: Design, Construction and Testing -Development and testing of low temperature Heat Pipes-Testing of Combination Heat Pipes and Peltier Elements-Prototype Cooling System: Design, Construction, Testing