Optimization of Thermoelectric Generators to Power Monitoring Platforms of SNF Canister Internal Conditions: Numerical Simulations

Spent nuclear fuel (SNF) may need to be stored in dry storage systems (DSS) for longer times than the systems were originally licensed for. Therefore, it is important to monitor the internal conditions of these canisters to ensure that their components and contents remain safe. The overall objective of the current research is to develop a wireless self-powered platform for monitoring the internal conditions of a wide variety of canister designs. The sensors and wireless data transmission systems will be powered using Thermoelectric Generators(TEGs) that harvest thermal energy from the decay heat of the SNF assemblies and convert it into electric power. The amount of harvested power by the TEGs depends on their dimensions and location. In this work, three-dimensional computational fluid dynamics (CFD) simulations are conducted to optimize the location of the TEGs within a NUHOMS 61-BT canister placed inside an HSM storage overpack. Two thicknesses of the TEGs are investigated to determine the optimal configuration that will maximize the amount of harvested power. The conversion efficiency of the TEGs is assumed to be temperature-dependent, and two different TEG figures of merit are considered. The electric power output of the TEGs and the frequency between measurements are determined for 50 years of storage. The results show that for a canister total heat generation of 18.3 kW and TEG surface area of 0.32 m 2 , TEGs with a 푍푇 value of 1 generate up to 66.10 mW of electric power, with an efficiency of 0.0760% at 0 years of storage and 8.85 mW (0.0290%) at 50 years of storage for a canister total heat generation of 7.2 kW. Assuming an energy consumption of 10.12 J for the wireless monitoring platform, a surface area of 0.1 m 2 is required to achieve a time between measurements of 8 minutes at 0 years of storage and 60 minutes at 50 years of storage.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

Master's Degree

Grantor

University of Nevada, Reno

Year dc:date.issued

2024

Author dc:creator

• Hager, Brandon

Advisors dc:contributor.advisor

• Hadj-Nacer, Mustafa
• Greiner, Miles

Committee members dc:contributor.committeemember

• Wang, Yan
• Yoon, Jihwan

• Computational Fluid Dynamics
• Dry Storage Systems
• Spent Nuclear Fuel
• Thermoelectric Generators

Repository record dc:identifier.uri

https://scholarwolf.unr.edu/handle/11714/10968

OAI identifier oai:identifier

oai:scholarwolf.unr.edu:11714/10968