Freeze range of a condensing gas propagating in a liquid helium-cooled tube

Journal Article · 07 December 2023 · Thermal Science and Engineering Progress

DOI: https://doi.org/10.1016/j.tsep.2023.102328 · OSTI ID:2229348

Bao, Shiran  ^[1]; Tang, Yuan ^[2]; Rababah, Qutadah  ^[2]; Guo, Wei  ^[2]

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1. Zhejiang University, Hangzhou (China); National High Magnetic Field Laboratory, Tallahassee, FL (United States)
2. National High Magnetic Field Laboratory, Tallahassee, FL (United States); Florida State University, Tallahassee, FL (United States)

Understanding air propagation and condensation following a catastrophic vacuum break in particle accelerator beamlines cooled by liquid helium is crucial for maintaining the operational safety of these facilities. Previous experimental investigations on nitrogen gas propagation in both normal liquid helium (He I) and superfluid helium (He II) cooled copper tubes unveiled a nearly exponential deceleration of the gas propagation. A comprehensive theoretical model incorporating gas dynamics, heat transfer, and condensation mechanisms has been developed, which effectively reproduces various key experimental observations. An intriguing phenomenon uncovered in our model simulation is that the gas propagation appears to nearly stop beyond a certain distance from the location where condensation starts. We refer to this distance as the freeze range. In this paper, we present our systematic study of the freeze range at various inlet mass fluxes and tube diameters. We show that the results can be well described by a simple correlation. The underlying physical mechanism that supports this useful correlation is explained. Knowing the freeze range may allow accelerator engineers to develop protocols for controlling frost-layer contamination in the beamline tubes, which is of great practical importance.

• Research Organization: Florida State Univ., Tallahassee, FL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP); National Science Foundation (NSF); USDOE
• Grant/Contract Number: SC0020113; DMR-2128556
• OSTI ID: 2229348
• Alternate ID(s): OSTI ID: 2229201
• Journal Information: Thermal Science and Engineering Progress, Vol. 47; ISSN 2451-9049
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English