Portland State University. Department of Physics
Date of Award
Master of Science (M.S.) in Physics
1 online resource (42 p.)
Heat -- Transmission -- Measurement
With the advent of the new high Tc superconductors, liquid nitrogen will be one of the preferred cryogens used to cool these materials. Consequently, a more thorough understanding of the heat transfer characteristics of liquid nitrogen is required. In our investigations we examine the transient heating characteristics of liquid nitrogen to states of nucleate and film boiling under different liquid flow conditions. Using a platinum hot wire technique, it is verified that there is a premature transition to film boiling in the transient case at power levels significantly lower than under steady state nucleate boiling conditions. It is also shown that the premature transition can be reduced or eliminated depending on the flow velocity.
Roth, Eric, "Transient heat transfer" (1991). Dissertations and Theses. Paper 4264.