Dr. Juliana Pacheco Duarte
Assistant Professor
Nuclear Engineering and Engineering Physics Department
University of Wisconsin-Madison

Abstract

This seminar will discuss current research efforts in the Heat Transfer and Safety Analysis Laboratory applicable to the safety of light water-cooled nuclear reactors. Particularly, Prof. Duarte will discuss experimental and computational research on the investigation of transient post-critical heat flux (post-CHF). The post-CHF heat transfer phenomena play a critical role in the prediction of the cladding temperature during anticipated operational occurrences (AOOs) and postulated accidents. For example, during a reactivity-initiated accident (RIA), the average cladding temperature—in the post-CHF film boiling heat transfer regime—should be below the temperature at which oxygen-induced embrittlement and fragmentation are expected. Currently, computational codes (such as CTF for subchannel analysis, TRACE and RELAP for system analysis, and BISON for fuel performance) use different approaches to predict the post-CHF heat transfer which leads to very significant model uncertainty, especially in the prediction of transient scenarios. Besides that, the use of different transition boiling heat transfer correlations can affect both the cladding surface temperature excursion rate and the peak cladding temperature for a given transient. The lack of consensus among correlations can be attributed to the different physical mechanisms taken into account in each case. Prof. Duarte will discuss the differences among existing models and experimental data, and how to improve our models using high-resolution data.

Biography

Juliana Pacheco Duarte, Ph.D., is an Assistant Professor in the Nuclear Engineering & Engineering Physics Department at the University of Wisconsin-Madison working on the safety analysis of nuclear reactors. Prior to joining UW-Madison, Prof. Duarte was an assistant professor of the Nuclear and Mechanical Engineering Programs at Virginia Tech. She received two B.S. degrees in Physics and Nuclear Engineering, an M.S. degree in Electrical Engineering from the top three universities in Brazil, and a Ph.D. in Nuclear Engineering and Engineering Physics from UW-Madison in 2018. She has worked on computational and experimental thermal hydraulics of advanced light water reactors and small modular reactors. Before coming to the U.S., she worked in the Thermal Hydraulics Division at the Brazilian Navy as a graduate researcher on designing critical heat flux experiments for a nuclear propulsion reactor. Her research interest is in experimental and computational two-phase flow and heat transfer, reactor safety, and risk analysis, and advanced reactor designs.

Thursday, March 7. 2024
4:00 pm seminar

zoom link upon request