CTF 4.0 User's Manual

Abstract

For a parallel run, a separate input file is required for each solution domain in the model. Each input deck should include the channels, rods, and gaps solved by that domain plus any additional ghost channels, rods, and gaps that are needed for sharing information with other solution domains. A single master input file is also required to summarize the total number of rods, channels, and gaps in the model, the global CTF mesh, as well as the total number of solution domains in the model. Creating parallel input files by hand can be confusing and error prone and, therefore, it is recommended that the CTF preprocessor, "xml2ctf", be used to automate this process. The default naming convention for the parallel input file is "pdeck.〈nproc〉.〈rank〉.inp" and "pmaster.inp" for the master input file. The term, "〈nproc〉" is the number of solution domains in the model and "〈rank〉" is the index of the solution domain described by the input file (using 1-based indexing). The custom naming convention for the parallel input file is "〈name〉.〈nproc〉.〈rank〉.inp" and "〈name〉.master.inp" for the master input file. The parallel simulation is run for default file names as:

DYN3D and CTF Coupling within a Multiscale and Multiphysics Software Development (Part II)

“…COBRA-TF is a subchannel code [53,54] created to deliver full mixing fluid dynamics in LWR (square geometry). It delivers full mixing fluid dynamics at the fuel pin level after providing fuel pin power distributions.…”

Ex-Core Radiation Transport Modeling with VERA User Manual

“…For VERA ex-core calculations, the Shift parameters are defined in the common VERA input [6] in the SHIFT block. All of the usual inputs for the STATE, CORE, ASSEMBLY, INSERT, CONTROL, DETECTOR, EDITS, MPACT [4], and COBRATF [5] blocks apply to their respective setups. To run any Shift calculation through VERA, the parameter in Listing 1 must be included in the first STATE block.…”

“…VERA provides the automated capability to launch independent Shift [1] fixed-source and eigenvalue MC calculations for user-specified state points during a standard VERA calculation. VERA couples MPACT [4] with COBRA-TF (CTF) [5] to Shift to perform ex-core tallies for multiple state points concurrently, with each component capable of parallel execution on independent processor domains. In these ex-core calculations, MPACT is coupled to CTF and performs the in-core depletion and heat transfer calculation, followed by a fixed-source Shift transport calculation on the entire geometry including ex-core regions to produce ex-core responses.…”

“…num_blocks_i × num_blocks_j should equal the total number of Shift processors. 5. Shift does not model any ex-core geometry (core only) when the problem_mode is set to eigenvalue.…”

NEAMS Milestone Report: M2MS–20OR030102 FW–CADIS PWR Ex-Core Analysis with Shift Through VERA

“…The purpose of this milestone was to optimize and further develop the ability to perform fully coupled ex-core analysis as applied to PWRs using Shift [2] through VERA. A fully coupled problem is one that couples pin-wise depleted compositions, fission source, temperatures, boron concentration, and moderator densities for each state point between MPACT [3] (with COBRA-TF (CTF) [4]) and Shift [5]. To achieve full coupling, a large memory footprint is needed for the Monte Carlo (MC) calculation, including the deterministic forward and adjoint calculations used for variance reduction.…”