Nuclear power plant operators are under constant pressure to reduce the operating cost of their assets. PWR operators are no exception, they are continuously looking for cost reduction in loading the reactor core together while at the same time satisfying challenging safety requirements. Finding the best PWR reload pattern fulfilling all the limiting criteria is a very complex task. The LPOpt software developed by UJV helps to solve this problem.

LPOpt main features:

  • LPOpt is the software developed by UJV for fast, robust, flexible and reliable PWR core loading pattern optimization maximizing fuel utilization and fulfilling operational and safety requirements in the best possible way.
  • LPOpt is based on the current state of the art combinatorial Estimation Distribution Algorithm (EDA) combined with a unique multi-objective pareto- optimality search concept developed at UJV to find suitable (sub-optimal or the best possible) loading patterns for user-predefined fuel assembly assortment. LPOpt is extremely robust, as it is designed to use a very small number of optimizer internal control parameters. Once defined by the user for a given optimization task (selected PWR core response parameters, fuel assembly assortment, and constraint conditions), they remain the same for all subsequent optimizations.
  • LPOpt is very flexible, since it allows users to define very general constraints (restrictions) on core response parameters, possible positions - fuel assembly types - fuel assembly rotations, and it also allows for a set of user-defined starting loading patterns (based on user expertise), which significantly speed up the convergence rate of the optimization process.
  • LPOpt is an extremely powerful and simple to use multi-parameter optimizer connected to an external PWR 2D-3D core simulator working as a black-box in stand-alone regime for parallelized, fast and accurate evaluation of user-selected core cycle response parameters.
  • LPOpt is extremely reliable, as it is able to find optimized fuel cycle patterns satisfying safety margins and additional user-specified constraints by evaluating up to millions of loading patterns per hour.
  • LPOpt is able to search for sub-optimal loading patterns in two basic regimes: fixed search – the number of available fuel assemblies is equal to the number of in-core positions; expanded search – the number of available fuel assemblies is greater than the number of core positions.
  • LPOpt was developed by UJV to provide a unique in-core fuel management tool with a simple and effective user interface, giving the user an immediate benefit.