Numerical simulation of flow and heat transfer between thermal column lead slab and core edge surfaces in a pool-type research reactor and enhancement of its cooling condition

Davari, Amin; Mirvakili, Seyed Mohammad; Abedi, Ebrahim; Sadat Ashkevar, SeyedMojtaba

Numerical simulation of flow and heat transfer between thermal column lead slab and core edge surfaces in a pool-type research reactor and enhancement of its cooling condition

Document Type : Research Paper

Authors

Amin Davari

seyed Mohammad Mirvakili

Ebrahim Abedi

SeyedMojtaba Sadat Ashkevar

Abstract

In pool-type research reactors, utilizing thermal column irradiation facilities through the fission process in the core, gamma rays are produced and absorbed by lead slab as a gamma rays shield of thermal column. Consequently, heat is generated in the lead slab surface which induces flow by the thermal buoyancy force. In the present work, 3D, CFD simulation of flow and heat transfer in a channel, formed by the thermal column and core edge, is considered. The aim is to obtain the temperature distribution on the lead surface and also a solution to prevent boiling, which may occur on the lead surface. It is observed that the hot spot on the lead surface exceeds the boiling point in natural convection mechanism. Therefore, the grid plate is extended underneath the channel so that water can flow through the channel and exit to the plenum causing forced convection to be established as an effective way to eliminate the boiling occurrence.

Keywords

Pool- type research reactor

Thermal column

Lead slab

CFD code

[1] S. Ramanathan, R. Kumar, Correlations for Natural convection Between Heated Vertical Plates Heated Asymmetrically, ASME Journal of Heat Transfer, 113 (1991) 97-107.

[2] W. Elenbaas, Heat dissipation of Parallel Plates by Free Convection, Physica, 9 (1942) 1-28.

[3] W. Aung, Fully Developed Laminar Free Convection Between Vertical Plates Heated Asymmetrically, International Journal of Heat and Mass Transfer, 15 (1972) 1577-1580.

[4] W. Aung, L.S. Fletcher, V. Sernas, Developing Laminar free convection Between Vertical Plates with Asymmetrics Heating, International Journal of Heat and Mass Transfer, 16 (1972) 2293-2308.

[5] T.A. Wirtz, R.J. Stutzman, Experiments on Free Convection Between Vertical Plates With symmetric Heating, ASME Journal of Heat Transfer, 104 (1982) 501-507.

[6] E.M. Sparrow, L.F.A. Azevedo, Vertical-channel Natural Convection Spanning Between the Fully-developed Limit and the Single-plate Boundary-layer Limit, International Journal of Heat and Mass Transfer, 28(10) (1985) 1847-1857.

[7] M.A. Langerman, Natural convection Heat transfer Analysis of ATR Fuel Elements, Technical Report, Technical Information Center Oak Ridge Tennessee, (1992).

[8] M. Azzoune, L. Mammou, M.H. Boulheouchat, T. Zidi, M.Y. Mokeddem, S. Belaid, A. Bousbia Salah, B. Meftah, A. Boumedien, NUR research reactor safety analysis study for long time natural convection (NC) operation mode, Nuclear Engineering and Design, 240 (2010) 823-831.

[9] Samiran. Sengupta, P.K. Vijayan, Anil. Pathrose, S.B. Chafle, K. Sasidharan, Three dimensional conjugate heat transfer analysis of BeO reflector assemblies of upgraded Apsara reactor, Int. J. Adv Eng Sci Appl Math, 4(3) (2012) 152-164.

[10] Y. Kasesaz, H. Khalafi, F. Rahmani, A. Ezati, M. Keyvani, A. Hossnirokh, M.A. Shamami, Design and construction of a thermal neutron beam for BNCT at Tehran Research Reactor, Applied Radiation and isotops, In Press, 94 (2014) 149-151.

[11] Atomic Energy Organization of Iran, Safety analysis report for Tehran research reactor (TRR), 1, (January 2009).

[12] Ansys Inc, Fluent User's Guide 14, (2011).

[13] B.E. Launder, D.B. Spalding, The Numerical Computation of Turbulent Flows, Computer Methods in Applied Mechanics and Engineering, 3 (1974) 269-289.

[14] D.C. Wilcox, Turbulence Modeling for CFD. DCW Industries, Inc., La Canada, California, (1998).

[15] D.B. Pelowitz, MCNPx User's Manual, Version 2.5.0, LA-CP-05-0369, (April 2005).