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Elmer, Thomas W.

Publications and source records attributed to Elmer, Thomas W..

FARM User Guidance and Instructions

The FARM (Feasible Actuator Range Modifier) module is a component of the RAVEN-based FORCE framework for the analysis of Integrated Energy Systems (IES). FARM aids HERON in the solution of the power dispatch problem by evaluating feasible set-point signals to be issued to the control systems of the different IES unit components. Set-points need to satisfy limits on both production variables (i.e., the variables to be optimized such as the electrical power, etc.) and process variables tied to the service life of equipment (e.g., steam flowrate, vessel pressure, turbine firing temperature, etc.). To enforce all these limits, a two-stage approach is adopted. First, the power dispatcher algorithm in HERON module estimates set-points that meet the constraints on the production variables, e.g., power levels and power ramp rate limits. These constraints are called explicit constraints. Then, if necessary, FARM adjusts these set-points to ensure the respect of the limits on the process variables of interest, given the knowledge of the system dynamics acquired through machine learning algorithms. These constraints are called implicit constraints. From this standpoint, FARM constitutes a bridge between the HERON power dispatcher that adopts a simplified description of the IES unit (low-resolution physics) and the HYBRID high-fidelity models (high-resolution physics). In this report, the general workflow and the software requirements of FARM module are summarized, and the detailed instructions for installing FARM software, running built-in example cases, deriving Linear Parameter-Varying (LPV) state-space models, and using FARM for user-defined power dispatch problems are provided.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Testing of In-Sodium Hydrogen Sensor

The goal of this project is to demonstrate diffusion-type in-sodium hydrogen meters (ISHMs) for real-time, in-situ monitoring of hydrogen concentration in molten sodium of a sodium-cooled fast reactor (SFR). The FY22 R&D efforts have been focused on (a) enhancement and fabrication of meshed ISHM prototype, (b) reconstruction of ISHM sodium test apparatus, (c) in-sodium test of meshed ISHM, and (d) ISHM performance and failure evaluations.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Sodium Hydrogen Sensor and Acoustic Flow Sensor Development

This report documents the development of diffusion-type hydrogen meters (DTHMs) as part of a steam generator leak detection system (SGLDS) of sodium-cooled fast reactors (SFR) and the demonstration of the capabilities of acoustic flowmeters, including a commercial UTFM (Flexim FLUXUS F721) and an Argonne HT acoustic flowmeter running on shear-to-longitudinal mode. It also evaluates two Argonne permanent magnet flowmeters (PMFMs).

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗