DEVELOPMENT OF A CONTINUOUS ENERGY VERSION OF KENO V.A

KENO V.a is a multigroup Monte Carlo code that solves the Boltzmann tr ansport equation and is used extensively in the nuclear criticality sa fety community to calculate the effective multiplication factor k(eff) of systems containing fissile material. Because of the smaller amount of disk storage and CPU time required in calculations, multigroup app roaches have been preferred over continuous energy (point) approaches in the past to solve the transport equation. With the advent of high-p erformance computers, storage and CPU limitations are less restrictive , thereby making continuous energy methods viable for transport calcul ations. Moreover, continuous energy methods avoid many of the assumpti ons and approximations inherent in multigroup methods. Because a conti nuous energy version of KENO V.a does nor exist, the objective of the work is to develop a new version of KENO V.a that utilizes continuous energy cross sections. Currently, a point cross-section library, which is based on a raw continuous energy cross-section library such as END F/B-V is nor available for implementation in KENO V.a; however, point cross-section libraries are available for MCNP, another widely used Mo nte Carlo transport code. Since MCNP cross sections are based on ENDF data and are readily available, a new version of KENO V.a named PKENO V.a has been developed that performs the random walk using MCNP cross sections. To utilize point cross sections, extensive modifications hav e been made to KENO V.a. At this point in the research, testing of the code is underway. In particular, PKENO V.a, KENO V.a, and MCNP have b een used to model nine critical experiments and one subcritical proble m. The results obtained with PKENO V.a are in excellent agreement with MCNP, KENO V.a, and experiments.