LightMAT - Continuous fiber malleable thermoset composites with sub-1-minute dwell times; validation of impact performance and evaluation of the efficacy of the compression forming process (CRADA 409 Final Report)

Rapid Reflective Facet Characterization Using Fringe Reflection Techniques

ASME 2009 3rd International Conference on Energy Sustainability, Volume 2 ◽

10.1115/es2009-90163 ◽

2009 ◽

Cited By ~ 14

Author(s):

Charles E. Andraka ◽

Scott Sadlon ◽

Brian Myer ◽

Kirill Trapeznikov ◽

Christina Liebner

Keyword(s):

Data Reduction ◽

Target Location ◽

Focal Length ◽

Complete Analysis ◽

Small Scale ◽

Shape Error ◽

Fringe Analysis ◽

Forming Process ◽

Impact Performance ◽

Slope Error

Mirror facets for Concentrating Solar Power (CSP) systems have stringent requirements on slope accuracy in order to provide adequate system performance. This paper presents a newly developed tool that can characterize facets quickly enough for 100% inspection on a production line. A facet for a CSP system, specifically a dish concentrator, has a parabolic design shape. This shape will concentrate near-parallel rays from the sun to a point (or a line for trough systems). Deviations of surface slope from the design shape impact the performance of the system, either losing power that misses the target, or increasing peak fluxes to undesirable levels. Three types of facet slope errors can impact performance. The first is a focal length error, typically caused by springback in the facet forming process. In this case, the wavelength of the error exceeds the size of the facet, resulting in a parabola, but with the wrong focal length. The results in a slope error that is largely systematic across the facet when the measured slope is compared to the design slope. A second shape error, in which the period of the error is on the order of the length of the facet, manifests also as a systematic slope error. In this case, the facet deviates from a parabolic shape, but can be modeled with a higher order curve. Finally, the residual errors after a model is proposed are usually lumped through a Root Mean Square (RMS) process and characterized as the 1-sigma variation of a normal distribution. This usually characterizes the small-scale imperfections in the facet, and is usually called “slope error”. However, all of these deviations from design are in facet errors in the slope of the manufactured facet. The reported characterization system, named SOFAST (Sandia Optical Fringe Analysis Slope Tool) has a computer-connected camera that images the reflective surface, which is positioned so that it views the reflection of an active target, such as an LCD screen. A series of fringe patterns are displayed on the screen while images are captured. Using the captured information, the reflected target location of each pixel of mirror viewed can be determined, and thus through a mathematical transformation, the surface normal map can be developed. This is then fitted to the selected model equation, and the errors from design are characterized. The reported system currently characterizes point focus mirrors (for dish systems), but extensions to line focus facets are planned. While similar approaches have been explored, several key developments are presented here. The combination of the display, capture, and data reduction in one system allows rapid capture and data reduction. An “electronic boresight” approach is developed accommodating physical equipment positioning errors, making the system insensitive to setup errors. A very large number of points are determined on each facet, providing significant detail as to the location and character of the errors. The system is developed in MatLab, providing intimate interactions with the data as techniques and applications are developed. Finally, while commercial systems typically resolve the data to shape determination, this system concentrates on slope characterization and reporting, which is tailored to the solar applications. This system can be used for facet analysis during development. However, the real payoff is in production, where complete analysis is performed in about 10 seconds. With optimized coding, this could be further reduced.

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Developing a research impact performance management system for The Research Council, Oman: Final Report

10.7249/rr833.1 ◽

2015 ◽

Author(s):

Joachim Krapels ◽

Molly Morgan Jones ◽

Sophie Castle-Clarke ◽

David Kryl ◽

Obaid Younossi

Keyword(s):

Performance Management ◽

Management System ◽

Research Council ◽

Research Impact ◽

Final Report ◽

Performance Management System ◽

Impact Performance

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CFCC applications for diesel engine valve guides. DOE Continuous Fiber Ceramic Composite Program. Phase II A/B - Final report

10.2172/761919 ◽

1999 ◽

Author(s):

Doug Twait ◽

Michael Long

Keyword(s):

Diesel Engine ◽

Phase Ii ◽

Ceramic Composite ◽

Final Report ◽

Continuous Fiber ◽

Engine Valve

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Continuous fiber ceramic composite. Phase I final report, April 1992--April 1993

10.2172/100172 ◽

1995 ◽

Author(s):

R.W. Goettler

Keyword(s):

Phase I ◽

Ceramic Composite ◽

Final Report ◽

Continuous Fiber

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STABILIZATION OF TUFF MATERIAL BY ELECTROSPINNING OF LOW AREAL WEIGHT TPU VEIL MATERIAL

10.12783/asc36/35855 ◽

2021 ◽

Author(s):

JOSEPH DEITZEL ◽

DIRK HEIDER ◽

ROGER CRANE ◽

TEKIN OZDEMIR

Keyword(s):

High Performance ◽

Mechanical Performance ◽

Volume Fraction ◽

Complex Geometry ◽

Fiber Material ◽

Short Fiber ◽

Continuous Fiber ◽

Forming Process ◽

Fiber Volume ◽

Carbon Fiber Material

The Tailored Universal Feedstock for Forming (TuFF) material is an aligned, discontinuous carbon fiber material with high fiber volume fraction up to 63% and mechanical performance equivalent to continuous fiber, unidirectional composites. The short fiber material allows at least 40% in-plane extension during processing enabling metal-like forming approaches simplifying composites manufacturing significantly. Traditionally, TuFF preforms are produced at areal weight (AW) of ~8 grams per square meter (gsm), stacked and impregnated with thermoset or thermoplastic polymer to create prepreg followed by curing/consolidation in an autoclave or stamp forming process resulting in high-performance structural parts. Here, the impregnated TuFF prepreg can be handled the same way as traditional continuous fiber prepreg. In contrast, to enable liquid composite molding (LCM) processes with TuFF material, the unimpregnated (dry) short fiber TuFF preforms must be stabilized for handling and preforming purposes. This paper details an electrospun veil approach as shown in Figure 1 to stabilize the individual TuFF sheets while maintaining the in-plane extensibility for complex geometry parts. Electrospun TPU fibers are applied onto the TuFF surface and then consolidated via a combination of heating and pressure, formingtrials were carried out using the stabilized preforms and composites werefabricated using LCM. Tensile tests show ~90-95% property retention versus theunstabilized baseline. The approach allows fabrication of stabilized TuFF fabricsfor the first time enabling the use of LCM processes for complex geometry parts.

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