A New Troughlike Nonimaging Solar Concentrator

2001 ◽  
Vol 124 (1) ◽  
pp. 51-54 ◽  
Author(s):  
Eduardo A. Rinco´n ◽  
Fidel A. Osorio
Keyword(s):  
Concentration Ratio ◽  
Glass Tube ◽  
Two Dimensional ◽  
Solar Concentrator ◽  
Steam Generation ◽  
Acceptance Angle ◽  
Practical Applications ◽  
Optimal Shapes ◽  
Heating Steam ◽  
East West

A new two-dimensional concentrator for solar energy collection has been developed. The concentrator has the following advantages, when compared with the classic Compound Parabolic Concentrators invented by Roland Winston, W. T. Welford, A. Rabl, Baranov, and other researchers: 1) It allows the use of parabolic mirrors, which have a reflecting area much smaller for a given concentration ratio and acceptance angle. 2) Between the mirror and the absorber, there is a large gap so that conduction losses are reduced. Convection losses can be reduced, too, if the absorber is enclosed within a glass tube. 3) It can be easily manufactured. Instead of seeking the shape of the mirrors for a given shape of the absorber, we have made the inverse statement of the problem, and we have obtained the optimal shapes of the absorbers with a prescribed acceptance angle, for parabolic mirrors, assuming that the intercept factor is unity, the mirrors are perfect, and the absorber surfaces are convex. The concentrator should be east-west oriented, and could be seasonal or monthly tilt adjusted. This concentrator could have many practical applications, such as fluid heating, steam generation, etc.

An Outdoor Experiment of a Lens-Walled Compound Parabolic Concentrator Photovoltaic Module on a Sunny Day in Nottingham

2013 ◽  
Vol 136 (2) ◽  
Author(s):  
Guiqiang Li ◽  
Yuehong Su ◽  
Gang Pei ◽  
Hang Zhou ◽  
Xu Yu ◽  
...  
Keyword(s):  
Concentration Ratio ◽  
Good Choice ◽  
Experimental Results ◽  
Photovoltaic Module ◽  
Solar Concentrator ◽  
Acceptance Angle ◽  
Compound Parabolic Concentrator ◽  
Pv Module ◽  
Outdoor Experiment ◽  
East West

A lens-walled compound parabolic concentrator (lens-walled CPC) has a larger half acceptance angle than a mirror CPC for the same geometrical concentration ratio of 2.5X, so it would be more suitable for the building-integrated application as a stationary solar concentrator. Based on our previous work, an outdoor experimental study of a sample trough lens-walled CPC PV module under sunny condition in Nottingham is described. The experimental results provide the verification of actual larger half acceptance angle obtained by the lens-walled CPC in comparison with a mirror CPC of the same size. Along with the analysis of the projected incidence angles, the experimental results also indicate that the lens-walled CPC of 2.5X orientated east–west may be a good choice for high latitude area as a stationary solar concentrator to give a satisfactory whole year performance.

scholarly journals Monte Carlo Ray-Tracing Simulation of a Cassegrain Solar Concentrator Module for CPV

2021 ◽  
Vol 9 ◽  
Author(s):  
Seung Jin Oh ◽  
Hyungchan Kim ◽  
Youngsun Hong
Keyword(s):  
Monte Carlo ◽  
Ray Tracing ◽  
Concentration Ratio ◽  
Collection Efficiency ◽  
Focal Length ◽  
Tracking Error ◽  
Target Area ◽  
Solar Concentrator ◽  
Acceptance Angle ◽  
Energy Applications

The concentration ratio is one of the most important characteristics in designing a Cassegrain solar concentrator since it directly affects the performance of high-density solar energy applications such as concentrated photovoltaics (CPVs). In this study, solar concentrator modules that have different configurations were proposed and their performances were compared by means of a Monte Carlo ray-tracing algorithm to identify the optimal configurations. The first solar concentrator design includes a primary parabolic concentrator, a parabolic secondary reflector, and a homogenizer. The second design, on the other hand, includes a parabolic primary concentrator, a secondary hyperbolic concentrator, and a homogenizer. Two different reflectance were applied to find the ideal concentration ratio and the actual concentration ratio. In addition, uniform rays and solar rays also were compared to estimate their efficiency. Results revealed that both modules show identical concentration ratios of 610 when the tracking error is not considered. However, the concentration ratio of the first design rapidly drops when the sun tracking error overshoots even 0.1°, whereas the concentration ratio of the second design remained constant within the range of the 0.8° tracking error. It was concluded that a paraboloidal reflector is not appropriate for the second mirror in a Cassegrain concentrator due to its low acceptance angle. The maximum collection efficiency was achieved when the f-number is smaller and the rim angle is bigger and when the secondary reflector is in a hyperboloid shape. The target area has to be rather bigger with a shorter focal length for the secondary reflector to obtain a wider acceptance angle.

Optical Analysis of a Heliostat Array With Linked Tracking

2013 ◽  
Vol 135 (3) ◽  
Author(s):  
M. T. Dunham ◽  
R. Kasetty ◽  
A. Mathur ◽  
W. Lipiński
Keyword(s):  
Concentration Ratio ◽  
Tracking System ◽  
Average Concentration ◽  
Solar Concentrator ◽  
Optical Performance ◽  
Optical Analysis ◽  
Optical Efficiency ◽  
The North ◽  
The Individual ◽  
East West

The optical performance of a novel solar concentrator consisting of a 400 spherical heliostat array and a linked two-axis tracking system is analyzed using the Monte Carlo ray-tracing technique. The optical efficiency and concentration ratio are compared for four different heliostat linkage configurations, including linkages of 1 × 1, 1 × 2, 2 × 2, 4 × 4, and 5 × 5 heliostats for 7-hour operation and the selected months of June and December. The optical performance of the concentrator decreases with the increasing number of heliostats in the individual groups due to increasing optical inaccuracies. In June, the best-performing linked configuration, in which 1 heliostat in the east-west direction and 2 heliostats in the north-south direction are linked, provides a monthly-averaged 7-hour optical efficiency and average concentration ratio of 79% and 511 suns, respectively. In December, the optical efficiency and the average concentration ratio decreases to 61% and 315 suns, respectively.

scholarly journals Experimental investigation of solar compound parabolic collector using Al2O3/H2O nanofluid in a subtropical climate

2020 ◽  
pp. 201-201
Author(s):  
Faria Akhtar ◽  
Muzaffar Ali ◽  
Nadeem Sheikh ◽  
Muhammad Shehryar
Keyword(s):  
Base Fluid ◽  
Concentration Ratio ◽  
Heat Transfer Fluid ◽  
Subtropical Climate ◽  
Solar Concentrator ◽  
Acceptance Angle ◽  
Flow Rates ◽  
Climate Conditions ◽  
Medium Range ◽  
Parabolic Collector

Different solar concentrator technologies are used for low-medium range temperature applications. In this paper, a non-tracking compound parabolic collector with a nanofluid is experimentally analyzed under real climate conditions of a typical sub-tropical climate Taxila, Pakistan. The collector used for the experimentation has concentration ratio of 4.17, collector area of 0.828 m2 and half acceptance angle of 24?. The heat transfer fluid used for the study is water based nanofluid with particles of Al2O3. The investigation is carried out at three different volumetric concentrations (0.025%, 0.05%,0.075%) of nanofluids at flowrates of 0.01 kg/s, 0.02 kg/s, 0.05 kg/s and 0.07 kg/s are compared with base fluid (water). Comparison of system thermal efficiency, solar heat gain, and temperature difference is presented for different selected days in real climate conditions during months of March to May. It is observed that performance of the compound parabolic collector is improved by 8%, 11%, 14% and 19%, respectively at considered flow rates compared to water.

scholarly journals Design and Evaluation of Polygonal Trough Solar Concentrator

2021 ◽  
Vol 34 (4) ◽  
pp. 10-16
Author(s):  
Yasser Yassin Khudair ◽  
Alaa Badr Hasan
Keyword(s):  
Concentration Ratio ◽  
Angle Of Incidence ◽  
Solar Concentrator ◽  
Acceptance Angle ◽  
Optical Efficiency ◽  
Cylindrical Mirror ◽  
Design For All ◽  
Reflecting Surfaces ◽  
Reflecting Surface ◽  
To Receive

     In this paper, a solar concentrator is designed in the form of a concave half-cylindrical mirror consisting of polygonal reflective surface plates. The plates are arranged to give a hemispherical shape to the design. These surfaces work to receive solar radiation and focusing by reflecting it to the receiver that is placed in front of the reflecting surfaces. The results are compared with a system consisting of a concave reflecting surface of the same dimensions to obtain a good criterion for evaluating the design performance. The results showed a low acceptance angle for the design for all the samples used due to the geometrical design nature. The optical efficiency affected by the angle of incidence greatly by all the samples used, which differ in the concentration ratio, width and location of the receiver.

Optical Analysis of a Two Stage XX Simultaneous Multiple Surface Concentrator for Parametric Trough Primary and Flat Absorber With Application in Direct Steam Generation Solar Thermal Plants

2016 ◽  
Vol 138 (2) ◽  
Author(s):  
Juan Pablo Núnez Bootello ◽  
Henry Price ◽  
Manuel Silva Pérez ◽  
Manuel Doblaré Castellano
Keyword(s):  
Concentration Ratio ◽  
Power Plants ◽  
Steam Generation ◽  
Tracking Accuracy ◽  
Parabolic Trough ◽  
Acceptance Angle ◽  
Direct Steam ◽  
Solar Power Plants ◽  
Well Differentiated

Today most commercial parabolic trough collector (PTC) solar power plants make use of the well-known LS3/Eurotrough optics. The PTC has a concentration ratio relative to the maximum thermodynamic limit equal to 0.31. In order to improve the competiveness of PTC technology, two well differentiated R&D strategies have been undertaken: (i) developing larger parabolic troughs, which places a higher demand in tracking accuracy and lower tolerances with respect to wind loads, quality of mirrors, control and assembly imprecisions, and (ii) developing secondary concentrators with the aim of bringing the concentration ratio relative to the maximum one as close to 1 as possible. In this paper, a parametric trough collector (PmTC) for a flat receiver designed with the simultaneous multiple surface (SMS) method is proposed. The method assumes zero transmission, absorption, and reflection optical losses and allows for both reflective primary and secondary surfaces (XX-reflective plus reflective) to be simultaneously designed, guaranteeing Etendue matching. The proposed PmTC geometry increases the referred ratio up to 0.59 with a rim angle greater than 100 deg and with the same effective acceptance angle as the PTC. The flat absorber can be replaced with a multitube receiver for application in direct steam generation (DSG).

Two-dimensional metal carbides and nitrides (MXenes): preparation, property, and applications in cancer therapy

Nanophotonics ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 2125-2145 ◽  
Author(s):  
Lu Ming Dong ◽  
Cui Ye ◽  
Lin Lin Zheng ◽  
Zhong Feng Gao ◽  
Fan Xia
Keyword(s):  
Cancer Therapy ◽  
Scientific Community ◽  
Critical Role ◽  
High Specific Surface Area ◽  
Future Perspective ◽  
Two Dimensional ◽  
Metal Carbides ◽  
Practical Applications ◽  
Two Dimensional Materials ◽  
Size And Morphology

AbstractTransition metal carbides and nitrides (MXenes), which comprise a rapidly growing family of two-dimensional materials, have attracted extensive attention of the scientific community, owing to its unique characteristics of high specific surface area, remarkable biocompatibility, and versatile applications. Exploring different methods to tune the size and morphology of MXenes plays a critical role in their practical applications. In recent years, MXenes have been demonstrated as promising nanomaterials for cancer therapy with substantial performances, which not only are helpful to clarify the mechanism between properties and morphologies but also bridge the gap between MXene nanotechnology and forward-looking applications. In this review, recent progress on the preparation and properties of MXenes are summarized. Further applications in cancer therapy are also discussed. Finally, the current opportunities and future perspective of MXenes are described.

scholarly journals Design and Fabrication of Absorptive/Reflective Crossed CPC PV/T System

Designs ◽  
2018 ◽  
Vol 2 (3) ◽  
pp. 29
Author(s):  
Muhsin Aykapadathu ◽  
Mehdi Nazarinia ◽  
Nazmi Sellami
Keyword(s):  
Numerical Control ◽  
Solar Concentrator ◽  
Cnc Milling ◽  
Acceptance Angle ◽  
Optical Efficiency ◽  
Compound Parabolic Concentrator ◽  
Building Integrated Photovoltaic ◽  
New Generation ◽  
Experimental Rig ◽  
T System

A crossed compound parabolic concentrator (CCPC) is a non-imaging concentrator which is a modified form of a circular 3D compound parabolic concentrator (CPC) obtained by orthogonal intersection of two 2D CPCs that have an optical efficiency in line with that of 3D CPC. The present work is about the design and fabrication of a new generation of solar concentrator: the hybrid photovoltaic (PV)/thermal absorptive/reflective CCPC module. The module has a 4× CCPC structure truncated to have a concentration of 3.6× with a half acceptance angle of 30°. Furthermore, an experimental rig was also fabricated to test the performance of the module and its feasibility in real applications such as building-integrated photovoltaic (BIPV). 3D printing and Computer Numerical Control (CNC) milling technologies were utilized to manufacture the absorber and reflective parts of the module.

Sign in / Sign up

Export Citation Format

Share Document