Linear Fresnel reflector (LFR) technology

Mills, David

doi:10.1533/9780857096173.2.153

Cited by 9 publications

(6 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Other angles of practical interest in concentration systems are the longitudinal angle of incidence θ l and transversal angle of incidence θ t . Both angles are shown schematically in Figure 3b, determined by Equations (5) and (6). where 0° α 180°, and sin γ 0 when α 90°.…”

Section: Solar Angles In a Lfrmentioning

confidence: 99%

“…Theoretically, this allows all mirrors to be connected using a simple four-bar mechanical coupling and driven with a single motor (rocker mechanism). However, the current designs of LFRs decide to move each mirror individually, because a more precise tracking is obtained, and it also allows a gradual defocusing if necessary [5]. Fresnel field configuration of FRESDEMO places the receiver of 0.6 m (a ) at a distance of 8 m of the primary mirrors (h f r ).…”

Section: Valuementioning

confidence: 99%

“…Most of these solar plants use solar fields with parabolic trough collectors (PTC) [2]. Notwithstanding, in recent years, Fresnel reflectors are among the most promising technologies to produce energy from concentrated solar radiation [3,4]; therefore, there has been an increasing interest in adopting Fresnel reflectors due to the low operating costs [5].…”

Section: Introductionmentioning

confidence: 99%

“…However, each row is tilted at different angles at any time, since they have different positions regarding the receiver. This allows a very large primary unit composed of relatively small reflectors, with a long focal length, which indeed leads to the possibility to use almost flat and low-cost glass mirror elements [4,5].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Methodology for an Opto-Geometric Optimization of a Linear Fresnel Reflector for Direct Steam Generation

González-Mora

García

2020

Energies

View full text Add to dashboard Cite

A methodology for an optical optimization of the intercept factor concerning a linear Fresnel reflector is described to increase the amount of solar irradiation that will be delivered in the absorber for Agua Prieta, Sonora; taking the FRESDEMO’s Fresnel field as the reference design. For the performed optimization, the intercept factor is determined as a function of the receiver’s height, establishing a simple criterion for the optimization. The FRESDEMO’s field description is determined and briefly discussed, next compared with the proposed optimization. The compound parabolic concentrator (CPC) Winston function for a circular absorber is modified to relocate the cusp of the reflector and the absorber. This modified CPC will redirect all the reflected rays that do not hit directly the absorber, as in the FRESDEMO field, so all of them are captured by the absorber. Through ray-tracing, the graphic flux distribution in the receiver aperture is conceived. This flux distribution is compared with the FRESDEMO field and with a PTC with a flat absorber, ensuring an adequate optimization regarding the intercept factor. The result of the opto-geometric optimization is compared between the FRESDEMO and the optimized field for a specified thermal process, addressing a considerable reduction in the length of the loops.

show abstract

Section: Solar Angles In a Lfrmentioning

confidence: 99%

Section: Valuementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Methodology for an Opto-Geometric Optimization of a Linear Fresnel Reflector for Direct Steam Generation

González-Mora

García

2020

Energies

View full text Add to dashboard Cite

show abstract

“…These heliostats move together in an elevation-Fresnel configuration as illustrated in Figure 1. The configuration consists of an array of mirrors that rotate around linked parallel axes, like a linear Fresnel reflector [17], but with an added elevation mechanism that inclines all those axes simultaneously in the North-South-Zenith plane. Thus, the arrangement of N facets is equivalent to N linked mini-heliostats moved by only two drives instead of 2N.…”

Section: Introductionmentioning

confidence: 99%

Development of an Elevation–Fresnel Linked Mini-Heliostat Array

et al. 2020

View full text Add to dashboard Cite

Heliostats are critical components of solar tower technology and different strategies have been proposed to reduce their costs; among them diminishing their size to reduce wind loads or linking nearby heliostats mechanically, to reduce the overall number of actuators. This document aims to describe the development of a linked array of mini-heliostats which move together in an elevation–Fresnel configuration. This configuration consists of an array of mirrors rotating around linked parallel axes, in a linear Fresnel style with an added elevation mechanism allowing all axes to incline simultaneously in the plane North–South–Zenith; that is equivalent to an array of N linked mini-heliostats moved by only two drives instead of 2N. A detailed analytical study of the Sun-tracking performance of this kind of heliostat arrays was carried out, and an 8-mirror prototype based on optical and mechanical analyses was designed, built and tested. Even though the mirrors are flat, the array produced a rather compact radiative flux distribution on the receiver. The flux distribution is compatible with a slope error of the order of 1 mrad. Peak and mean concentration ratios reached 6.89 and 3.94, respectively.

show abstract