Engineering topics

Farrell, Tucker

Publications and source records attributed to Farrell, Tucker.

3 records

DOE OSTI2024

Improvements in Optical Surface Measurement Using Reflected Computer Vision Targets

Since 2021, NREL has been developing a system to measure heliostats by measuring the deflection of printed computer vision targets, called the Reflected Target Non-intrusive Assessment (ReTNA) [6], [7]. While this system will have lower resolution than a fringe deflectometry system, it has several important advantages that make it a complimentary technology: 2D surface slope measurement can be generated from a single image, it can operate in ambient lighting, target points can be directly located in 3D space with photogrammetry allowing for a non-flat target, and it's well suited to using a smaller target, and multiple images to measure larger optical surfaces. ReTNA has undergone several significant changes and improvements, described below. This talk will summarize new system layouts designed for commercial use, new computer vision algorithms used to automate the analysis process and validation campaigns for the ReTNA software.

computer vision↗

DOE OSTI2024

Heliostat Consortium Annual Report: 2024

In 2021, the U.S. Department of Energy's (DOE's) Solar Energy Technologies Office (SETO) funded the formation of the Heliostat Consortium (HelioCon), a five-year consortium designed to advance U.S. heliostat technologies by engaging industry, subject matter experts, and general stakeholders for direct project-level collaboration, external consulting, and mission-specific panels and workshops. HelioCon is led by the National Renewable Energy Laboratory (NREL) and Sandia National Laboratories, in partnership with the Australian Solar Thermal Research Institute. This report describes HelioCon's activities and impact in fiscal year 2024.

14 SOLAR ENERGY↗

DOE OSTI2024

A Novel Concentrating Solar Weathering Apparatus for Experimental Validation of Multi-Modal Degradation Models

High-performance coatings for Concentrating Solar Power (CSP) receivers are subjected to remarkable environmental stressors during normal operations. Applied to the receiver tubes, these coatings serve to maximize the solar absorptivity of the receiver, transferring as much heat as possible from the solar collectors into the heat-transfer fluid (HTF). The lifecycle of these coatings is not well-defined, and the harsh operational conditions make them difficult to test. NREL has designed, built, and tested an apparatus to expose these samples to design levels of environmental stress and well beyond, into accelerated and destructive conditions. The chamber is actively cooled, monitored, and has the capability to supply humidification for cycling tests, allowing us to test multi-modal degradation and failure conditions at high temperature, high flux, and high humidity conditions. These conditions can catalyze high-temperature oxidation, mechanical degradation, and other modes of absorptivity loss seen in selective solar receiver coatings. The experimental data can feed lifecycle models for expensive and necessarily resilient materials, offering insights to aid maintenance schedules, technoeconomic analysis, and material industry performance benchmarks. This presentation will demonstrate the apparatus design and performance, as well as initial results for aging on a selective receiver coating.

14 SOLAR ENERGY↗