Doctoral Dissertations

Keywords and Phrases

Advanced Heat Transfer Probe; Heat Transfer Coefficient; Natural Convection; Nonuniform Heat; Nusselt Number; Prismatic Modular Reactor


“Gas-cooled reactor (GCR) is being developed under the Next Generation Nuclear Plant Program (NGNP) in nuclear engineering studies. As the world searches for an energy source with high energy density, clean, abundant, and storable nature to avoid global warming issues, GCR seems to be a promising solution, particularly the possibility of producing hydrogen. Studying and developing the safety analysis and GCR technologies are required for the optimum design and safety of GCR system. Multiphase Reactors Engineering and Applications Laboratory (mReal) at Missouri University of Science and Technology (S&T) has developed a natural convection heat transfer test facility with one riser and one downcomer between two plena to investigate loss of flow accident scenario (LOFA) for a prismatic very high temperature reactor (VHTR). Using advanced heat transfer coefficient probe and T-thermocouples. The facility represents a scaled down prismatic modular reactor with a reference to High-Temperature Test Facility at Oregon State University (OSU-HTTF). The natural circulation heat transfer in terms of temperature fields and heat transfer coefficients across the core of current facility (i.e., channels) has been investigated at different conditions to understand the passive safety features of prismatic modular reactors (PMR). This dissertation advance knowledge and understanding of the intra core natural circulation phenomenon in the PMRs. Moreover, fill the gaps in the open literature and understanding of the natural circulation heat transfer and gaseous dynamics in the prismatic VHTR and provide experimental benchmark data, which is much needed and is missing in the literature for verification and validation”--Abstract, page iii.


Usman, Shoaib

Committee Member(s)

Castano Giraldo, Carlos Henry
Alajo, Ayodeji Babatunde
Alagha, Lana Z.
Abdallah, Ibrahim


Nuclear Engineering and Radiation Science

Degree Name

Ph. D. in Nuclear Engineering


The author would like to acknowledge King Abdulaziz City for Science and Technology in Riyadh (KACST), Saudi Arabia for sponsoring my Ph.D. studies, and Saudi Arabian Cultural Mission (SACM) in Washington, D.C. USA for their support.


Missouri University of Science and Technology

Publication Date

Spring 2019


xiii, 151 pages

Note about bibliography

Includes bibliographic references (pages 137-150).


© 2019 Salman Mohammed Alshehri, All rights reserved.

Document Type

Dissertation - Open Access

File Type




Thesis Number

T 12073