KENO: A Multigroup Monte Carlo Criticality Program

Technical Report · Wed Sep 10 04:00:00 EDT 1969

DOI:https://doi.org/10.2172/4780107· OSTI ID:4780107

Whitesides, G. E. ^[1]; Cross, N. F. ^[1]

---

1. Oak Ridge Y-12 Plant (Y-12), Oak Ridge, TN (United States)

KENO is a multigroup Monte Carlo criticality program written in Fortran IV, level H, for the IBM 360-65 and 360-75 computers. It contains a special geometry package which allows easy description of systems composed of cylinders, spheres, and cuboids (rectangular parallelepipeds) arranged in any order with only one restriction. This restriction is that each geometrical region must be described as completely enclosing all regions interior to it. For systems not describable using this special geometry package, the program can use the generalized geometry package (GEOM) developed for the 05R Monte Carlo code. It allows any system that can be described by a collection of planes and/or quadric surfaces, arbitrarily oriented and intersecting in arbitrary fashion. Rectangular arrays of fissile units are allowed with or without external reflector regions. The scattering treatment used in KENO assumes that the differential neutron scattering cross section can be represented by a P₁ Legendre polynomial. Absorption of neutrons in KENO is not allowed. Instead, at each collision point of a neutron tracking history the weight of the neutron is reduced by the absorption probability. When the neutron weight has been reduced below a specified point for the region in which the collision occurs, Russian roulette is played to determine if the neutron's history is to be terminated at that point or if the neutron is to survive with an increased weight. Splitting of high weight neutrons is allowed in order to minimize the variance in k_eff. for systems with regions of widely varying average weights. Output from KENO consists of k_eff for the system plus an estimate of its standard deviation and the leakage, absorption, and fissions for each energy group plus the totals for all groups.

• Research Organization: Oak Ridge Y-12 Plant (Y-12), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP); US Atomic Energy Commission (AEC)
• DOE Contract Number: W-7405-ENG-26
• NSA Number: NSA-23-047334
• OSTI ID: 4780107
• Report Number(s): CTC-5
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
97 MATHEMATICS AND COMPUTING
COMPUTERS
CONFIGURATION
CRITICALITY
Computer Program
Criticality
Criticality Calculation
DIGITAL SYSTEMS
FORTRAN
FORTRAN 4
FORTRAN IV
IBM 360
KENO
KENO-CODE
MONTE CARLO METHOD
Monte Carlo Method
Multigroup
N38930* --Reactor Theory--Experimental Applications
Nuclear Criticality Safety Program (NCSP)
PROGRAMMING
REACTORS