Mu2e Collaboration



Mu2e Document 10979-v1

Helium Relief Simulations for Quench and Loss of Vacuum (DS, PS, and TS Solenoids)

Document #:
Mu2e-doc-10979-v1
Document type:
Tech Doc
Submitted by:
Erik A Voirin
Updated by:
Erik A Voirin
Document Created:
13 Jun 2017, 09:47
Contents Revised:
13 Jun 2017, 09:48
DB Info Revised:
13 Jun 2017, 09:48
Viewable by:
  • Public document
Modifiable by:
Abstract:
Scope of Calculations:
We simulate the pressure rise and helium relief capacity seen in the helium lines of the Mu2e Solenoids from with complete loss of vacuum, which would also induce a quench. Relief valves for all three solenoids must have the same set point, and we would like them to be as high as possible for cool down reasons. The Solenoids have a design rating of 285 psid, and allowable overpressure of 10% = 313.5 psid. It was found 200 psi relief valves would provide adequate pressure relief for all three cases.
Simulation Methods:
We perform transient thermal FEA and CFD analyses of representative sections of the Solenoids and Helium contained inside to calculate the heat load on the helium itself. Quench energy is calculated and included as volumetric heat sources in the mandrel and coil. Loss of vacuum heat flux obtained from experiments by Lehmann and Zahn is added to external surfaces of the solenoids, and equivalently volumetrically to all other helium tubes. These Heat loads are then used in fluid simulations complete with all tubing sections, check valves, and relief valves, simulating the thermal expansion and pressure rise of the fluid, Joule Thomson effects, pressure drop from inertial and viscous losses, and expulsion out the relief valves. Helium properties are obtained from a custom taskflow RGP file generated by NIST_to_RGP Fortran code using a NIST RefProp.fld file, so are the most accurate available. Pressure Drop is simulated by quadratic momentum loss model source term, which is set appropriately for each pipe size. The fluid simulation code has been verified by testing it on a simple case from another helium relief code “HeDump” given in literature for helium expulsion from solenoid quenches.
Results:
We show the solenoids can be relieved, and pressure kept below allowable using the following relief valve sizes: Anderson Greenwood Series 81 has these sizes, though any similar relief valve would work. High blowdown would beneficial to reduce chattering.
DS Solenoid Relief Sizes: (200 psig set point)
Return PSV: 0.503 [in^2] Discharge Coefficient: 0.816
Supply PSV: 0.196 [in^2] Discharge Coefficient: 0.816
PS Solenoid Relief Sizes: (200 psig set point)
Return PSV: 0.196 [in^2] Discharge Coefficient: 0.816
Supply PSV: 0.110 [in^2] Discharge Coefficient: 0.816
TS Solenoid Relief Sizes: (200 psig set point)
Return PSV: 0.196 [in^2] Discharge Coefficient: 0.816
Supply PSV: 0.110 [in^2] Discharge Coefficient: 0.816

Files in Document:
Other Files:
DocDB Home ]  [ Search ] [ Last 20 Days ] [ List Authors ] [ List Events ] [ List Topics ]

--------
Security, Privacy, Legal
Fermilab Policy on Computing
Fermi National Accelerator Laboratory

For assistance contact HelpDesk



DocDB Version 8.7.23, contact Document Database Administrators