V&V

Verification and Validation Symposium

Hyatt Regency Minneapolis, Minneapolis, MN

Conference
May 16 - 18, 2018

 
 

Program - Challenge Problems

 

V&V BENCHMARK PROBLEM —TWIN JET COMPUTATIONAL FLUID DYNAMICS (CFD) NUMERIC MODEL VALIDATION

The ASME Verification and Validation in Computational Nuclear System Thermal Fluids Behavior Committee (ASME V&V 30) is supporting a series of verification and validation (V&V) benchmark problems designed to:

Study the scope and key ingredients of the V&V30 Committee's charter, achieve the above objective by using new, high-quality, state-of-the-art validation data sets obtained specifically for this purpose, and achieve the above objectives using a stepwise, progressive approach characterized by focusing on each key ingredient individually in a benchmark problem designed for that purpose.

The first V&V benchmark problem in the series was initiated for the 2016 ASME V&V Symposium and the results and findings from the first V&V benchmark problem were presented and discussed during the 2017 Symposium. The full spectrum of upcoming benchmark problems are currently being considered.

A Summary Description of the First Problem: In the context of investigating the mixing between and the penetration of two parallel twin jets which are typical for an advanced liquid metal-cooled reactor a scaled twin-jet experiment was designed to obtain validation data at Reynolds numbers typical of operational conditions in the upper plenum of the liquid metal-cooled reactor. These data may also characterize twin-jet behavior in the lower plenum of a very high temperature reactor. In addition, the test facility may also be used to obtain natural circulation data characterizing twin-jet behavior in the upper plenums of both a liquid-metal cooled reactor and the very high temperature gas-cooled reactor. In the experiment, the working fluid is water and the velocity field was measured in detail using advanced particle image velocimetry (PIV) and laser Doppler anemometry (LDV) with measurement uncertainties estimated using accepted ASME practices for experimental uncertainty (ASME PTC 19.1 Test Uncertainty).

Objective of the First Problem: Using a select set of data from the twin-jet experiment (provided by the ASME and organizers), apply the V&V practices necessary to ensure an appropriately validated computational solution is obtained. For those participants from the nuclear community, the V&V 30 Committee encouraged them to use whatever V&V practices they would normally use in the context of preparing a document which they might submit to the U.S. Nuclear Regulatory Commission for review.

Protocol for Participating in the First Problem: The participating organization or individual who would like to take part in the benchmark exercise is request that they perform their V&V assessment using the standard protocol and procedures accepted by their engineering community and sponsoring organization. It was noted that this benchmark effort was not intended as a competition among companies or individuals, but rather was intended as a demonstration of the state of the practice in using and applying computational tools to support U.S. Nuclear Regulatory Commission or other regulatory reviews. The outcomes of this first benchmark effort are lessons learned, review of V&V methods, and effectiveness of V&V methods to support modeling and simulation reviews. The results of the various participants will be summarized and compared in a subsequent report to be presented by the benchmark problem committee at the 2018 V&V Symposium.

The experimental data set can be found at the Thermal-Hydraulic Research Laboratory website. If you have any questions and/or would like to be included in the program, please email the ASME Subcommittee 30 Staff Secretary, Michelle Pagano, at PaganoM@asme.org .