Hope College Department of Physics and Engineering Research Experiences for Undergraduates Summer 2005 Project Summary

Practical analysis of transient or non-steady behavior of very low temperature thermal systems of -300 F and colder has been difficult due to the interaction of multiple complex thermal fluid phenomena. Underlying processes include temperature dependent thermo physical properties, multiple modes of heat transfer, and two phase fluid flow. Recently a general purpose thermal fluid analysis application called Sinda/Fluint has been made available with a simplified user interface to facilitate modeling of large scale system behavior. This software has the potential to be used to model a wide range of transient behavior in low temperature systems. To help evaluate this potential, the cool down of a copper pipe from room temperature to -321 F using liquid nitrogen was modeled using Sinda/Fluint. Measurements were also made on a simplified apparatus. Results show reasonable agreement for total cool down time and general features of cool down behavior between analysis and experiment.

Publications:
Olive Stohlman, John Krupczak, Jr., Ahmed Sidi-Yekhlef, "Analysis and Design of Helium Gas Warm Up for a 2K RF Cryomodule", Brookhaven National Laboratory, Technical Note, November 11, 2005