Engineering Commons^™

Development And Characterization Of Nanostructured Steels And High Entropy Alloys For Nuclear Applications, Andrew Kalevi Hoffman

Doctoral Dissertations

"Nuclear reactor materials are subjected to a harsh environment including high temperatures and radiation fluences. In order to extend the lifetime of current light water reactors (LWRs) and realize the development of advanced Gen IV nuclear reactors new materials must be developed which can withstand such an environment. This thesis involves two approaches to solving this materials problem: advanced manufacturing of current commercial alloys using severe plastic deformation (SPD) and the development of new advanced high entropy alloys (HEAs).

Because SPD is effective at achieving grain refinement, this technique was used to obtain material having a high volume fraction of …

Sensitivity Of Vver-1000 Spent Fuel Pin Nuclide Inventory To Operational Parameters, Nicholas Patrick Luciano

Doctoral Dissertations

Tools that can rapidly compute the isotopic composition of spent nuclear fuel (SNF) are useful for many reasons, including safety and security. Although tools exist to compute approximate isotopic compositions, detailed fuel composition requires reactor simulation that result from normal and off-normal operations. Reactor simulation is typically performed using nodal core simulators. These codes perform their calculations rapidly, but they may not compute isotopic composition.

The Russian designed VVER is a pressurized water reactor that uses hexagonal fuel assemblies with triangularly pitched fuel rods and annular pellets. The international expansion of VVER-1000 reactor technology has motivated a renewed interest in …

Development Of A Reactor Physics Analysis Procedure For The Plank-Based And Liquid Salt-Cooled Advanced High Temperature Reactor, Cole Andrew Gentry

Doctoral Dissertations

Presented in this dissertation is the investigation and development of an adapted lattice physics-to-core simulator two-step procedure based on the SERPENT 2 and NESTLE neutronics codes for the rapid analysis of the Advanced High Temperature Reactor (AHTR). AHTR specific characteristics, such as its longer neutron diffusion length and double heterogeneity of TRISO fuel particles, were taken into consideration when adapting the traditional Light Water Reactor (LWR) lattice to nodal diffusion procedure to AHTR applications. The coarse energy group structure was re-optimized from the traditional LWR 2-group structure to an alternative 4-group structures to address the AHTR specific flux spectrum and …