Author : Nathaniel M. Garceau
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (135 download)
Book Synopsis Heat and Mass Transfer During a Sudden Loss of Vacuum in a Liquid Helium Cooled Tube by : Nathaniel M. Garceau
Download or read book Heat and Mass Transfer During a Sudden Loss of Vacuum in a Liquid Helium Cooled Tube written by Nathaniel M. Garceau and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are many safety concerns with cryogenic systems around the world such as particle accelerators. One large concern is the sudden loss of vacuum within the particle accelerator systems. Loss of vacuum can lead to catastrophic equipment and facility damage as well as possible personnel injury. To mitigate risk and improve safety during operation of particle accelerator systems, a clear understanding of the dynamic and complex heat and mass transfer processes after a vacuum break is needed. Research in our lab focuses on the simulation of a sudden loss of vacuum in liquid helium cooled superconducting particle accelerator beam-line tubes. Loss of vacuum is simulated using an evacuated copper tube cooled in liquid helium and suddenly venting nitrogen gas from a buffer tank into the tube. Abrupt temperature rise by thermometers mounted to the tube's wall marked the location of the gas propagating front. Previous experiments and analysis in our lab using normal helium (He~I) and preliminary studies in superfluid helium (He II) observed an exponential slowing of the gas propagating front (Dhuley and Vansciver, 2016). Condensation of the nitrogen gas onto the tube walls was shown to be the reason for the exponential slowing, but the underlying analysis and explanation of the gas dynamics and condensation was limited. This dissertation describes the continuation and evolution of our lab's experiments, and improvements in the quantitative analysis to better explain the underlying physical mechanisms of the slowing down process in both He I and He II. Further systematic experimental and simulation work using different mass flow rates into the evacuated tube were conducted to determine the applicability and robustness of the model in both He I and He II. The improved understanding of the physics of a vacuum break in a liquid helium cooled tube could have practical uses by improving particle accelerator safety.
