Effect of Nuclear Fuel Particle Movement on Nuclear Criticality in a Rotating Cylindrical Vessel

In conventional criticality safety evaluations of nuclear facilities, nuclear fuel particle behavior could not be considered because any appropriate computational tools did not be developed. A new criticality evaluation tool, which can consider the particle behavior, is developed by coupling a Discrete Element Method with a continuous energy Monte Carlo type code. Criticality evaluations considering the nuclear particle movement in a rotating cylindrical tank are performed by applying this tool. Effects of the powder-filling ratio and the rotating speed on nuclear criticality are investigated in the present study. The nuclear powder free surface is fluctuated more remarkably as the filling ratio and the rotating speed are higher. The fluctuation makes the effective multiplication factor lower because of neutron leakage from the system by the increase of the superficial area and reduction of the atomic number densities due to the flowability.

[1]  R. Watanabe,et al.  Simulation of Ball Motion for Analysis of Coating Phenomena during Tumbler-Ball Milling of Cu Powder , 1994 .

[2]  R. Venugopal,et al.  3D simulation of charge motion in tumbling mills by the discrete element method , 2001 .

[3]  Paul W. Cleary,et al.  Predicting charge motion, power draw, segregation and wear in ball mills using discrete element methods , 1998 .

[4]  Brahmeshwar Mishra,et al.  A review of computer simulation of tumbling mills by the discrete element method: Part I—contact mechanics , 2003 .

[5]  Richard P. Jensen,et al.  Discrete Element Methods: Numerical Modeling of Discontinua , 2002 .

[6]  P. Cundall,et al.  A discrete numerical model for granular assemblies , 1979 .

[7]  D. Kilgour,et al.  The density of random close packing of spheres , 1969 .

[8]  J. F. Briesmeister.  MCNP-A General Monte Carlo N-Particle Transport Code , 1993 .

[9]  M. Sakai,et al.  Development of a Criticality Evaluation Method Considering the Particulate Behavior of Nuclear Fuel , 2005 .

[10]  Brahmeshwar Mishra,et al.  Mechanics of media motion in tumbling mills with 3d discrete element method , 1997 .

[11]  A. Misra,et al.  Particle motion and energy distribution in tumbling ball mills , 1999 .

[12]  E. Liniger,et al.  Random loose packings of uniform spheres and the dilatancy onset. , 1990, Physical review letters.

[13]  John M. Ting,et al.  Computational Laboratory for Discrete Element Geomechanics , 1992 .

[14]  C.R.E. de Oliveira,et al.  Space-dependent kinetics simulation of a gas-cooled fluidized bed nuclear reactor , 2003 .