A Research Program onVery High Temperature Reactors

(DOE-NERI-C-08-043)MU-WashU/MST-NCSU

Faculty: S. K. Loyalka (MU, PI), M. Al Dahaan (WashU/MST), R. P. Gardner (NCSU), T. K. Ghosh (MU), M.A. Prelas (MU), R. V. Tompson (MU), D.S. Viswanath (MU)

Additional MU Participants:Post Doctoral Fellows: R. Meyer, E. L. TiptonPhD Students: S. Boddu, T. Boyle, S. Branney, V. Gutti, L. Lee, R. Maynard, A. Mohan, Z. Smith, R. Troy, K. Walton, J. Wilson

VHTR’sResearch ProgramResearch Focus at MU

Very High Temperature Reactors Gen IV reactors Two design types▪ Prismatic▪ Pebble Bed

High thermal efficiency ( ~ 48 %) Operating temperatures of 900-1000 ˚C allow

greater thermal efficiency than current LWR designs (~300 ˚C, ~30-35%)

Not affected by coolant phase change Prismatic and PBMR designs use helium as coolant

Process heat can be used for Hydrogen production etc.

Need data/models in many areas including areas that are focus of our research:

• Diffusion of Fission Products• Adsorption of Fission Products• Emissivity from Surfaces• Dust Generation/Deposition/Re-

suspension• Gas, Particle and Pebble Flows

Diffusion of Fission Products (e.g. Silver)

Adsorption Isotherms

Fission products of interest Cesium Strontium Iodine Silver Palladium

Adsorption data needed for plate out calculations under normal and accident conditions

To obtain accurate adsorption data, accurate VP data is required

VP data exists for all five elements Limited temperature ranges considered

We have analyzed the available VP data and identified needs for additional data

Adsorption Experimental Setup

Experiments initially carried out using CsI vapor

CsI was adsorbed on SS sample EDS did not allow characterization of

adsorption mechanism

Emissivity Measurements

Emissivity data

Dust Generation

Graphite Dust Generation

Nano Particle Generation

Particle deposition Experiments

Initial Data

Single Particle Measurements

Conclusions

VHTR’s are very attractive from engineering and economic viewpoints, and are viewed as the Next Generation of Nuclear Power Plants (NGNP) by DOE.

There are many research challenges, and MU faculty and students (together with the consortium faculty and students from MST and NCSU) are contributing to meeting these challenges under DOE sponsorship.