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You searched for subject:(Incidence Angle Modifier). Showing records 1 – 3 of 3 total matches.

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De Montfort University

1. Hess, Stefan. Low-concentrating, stationary solar thermal collectors for process heat generation.

Degree: PhD, 2014, De Montfort University

The annual gain of stationary solar thermal collectors can be increased by non-focusing reflectors. Such concentrators make use of diffuse irradiance. A collector’s incidence angle modifier for diffuse (diffuse-IAM) accounts for this utilization. The diffuse irra-diance varies over the collector hemisphere, which dynamically influences the diffuse-IAM. This is not considered by state-of-the-art collector models. They simply calculate with one constant IAM value for isotropic diffuse irradiance from sky and ground. This work is based on the development of a stationary, double-covered process heat flat-plate collector with a one-sided, segmented booster reflector (RefleC). This reflector approximates one branch of a compound parabolic concentrator (CPC). Optical meas-urement results of the collector components as well as raytracing results of different variants are given. The thermal and optical characterization of test samples up to 190 °C in an outdoor laboratory as well as the validation of the raytracing are discussed. A collector simulation model with varying diffuse-IAM is described. Therein, ground reflected and sky diffuse irradiance are treated separately. Sky diffuse is weighted with an anisotropic IAM, which is re-calculated in every time step. This is realized by gener-ating an anisotropic sky radiance distribution with the model of Brunger and Hooper, and by weighting the irradiance from distinct sky elements with their raytraced beam-IAM values. According to the simulations, the RefleC booster increases the annual out-put of the double-covered flat-plate in Würzburg, Germany, by 87 % at a constant inlet temperature of 120 °C and by 20 % at 40 °C. Variations of the sky diffuse-IAM of up to 25 % during one day are found. A constant, isotropic diffuse-IAM would have under-valued the gains from the booster by 40 % at 40 °C and by 20 % at 120 °C. The results indicate that the gain of all non-focusing solar collectors is undervalued when constant, isotropic diffuse-IAMs calculated from raytracing or steady-state test data are used. Process heat generation with RefleC is demonstrated in a monitored pilot plant at work-ing temperatures of up to 130 °C. The measured annual system utilization ratio is 35 %. Comparing the gains at all inlet temperatures above 80 °C, the booster increases the an-nual output of the double-covered flat-plates by 78 %. Taking all inlet temperatures, the total annual gains of RefleC are 39 % above that of the flat-plates without reflectors. A qualitative comparison of the new simulation model results to the laboratory results and monitoring data shows good agreement. It is shown that the accuracy of existing collector models can be increased with low effort by calculating separate isotropic IAMs for diffuse sky and ground reflected irradiance. The highest relevance of this work is seen for stationary collectors with very distinctive radiation acceptance.

Subjects/Keywords: 333.79; solar thermal collector; Collector Testing and Simulation; Solar Process Heat; Incidence Angle Modifier; Anisotropic Diffuse Irradiance; CPC Collector; Booster Reflector; Brunger-Model; Laundry

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APA (6th Edition):

Hess, S. (2014). Low-concentrating, stationary solar thermal collectors for process heat generation. (Doctoral Dissertation). De Montfort University. Retrieved from http://hdl.handle.net/2086/10874

Chicago Manual of Style (16th Edition):

Hess, Stefan. “Low-concentrating, stationary solar thermal collectors for process heat generation.” 2014. Doctoral Dissertation, De Montfort University. Accessed December 12, 2018. http://hdl.handle.net/2086/10874.

MLA Handbook (7th Edition):

Hess, Stefan. “Low-concentrating, stationary solar thermal collectors for process heat generation.” 2014. Web. 12 Dec 2018.

Vancouver:

Hess S. Low-concentrating, stationary solar thermal collectors for process heat generation. [Internet] [Doctoral dissertation]. De Montfort University; 2014. [cited 2018 Dec 12]. Available from: http://hdl.handle.net/2086/10874.

Council of Science Editors:

Hess S. Low-concentrating, stationary solar thermal collectors for process heat generation. [Doctoral Dissertation]. De Montfort University; 2014. Available from: http://hdl.handle.net/2086/10874

2. Pujol Nadal, Ramon. Comportamiento Óptico y Térmico de un Concentrador Solar Lineal con reflector estacionario y Foco Móvil.

Degree: Departament de Física, 2012, Universitat de les Illes Balears

The Fixed Mirror Solar Concentrator (FMSC) appeared during the 70s with the aim of reducing costs in the production of electricity in solar thermal power plants. This design consists of a concentrator with fixed reflector and moving receiver, has a very good integrability into building roofs and can reach temperatures between 100 and 200ºC with an acceptable efficiency. In this Thesis a methodology is presented for the determination of the behaviour of the FMSC. A simulation tool based on the forward ray-tracing method has been developed. The optical and thermal behaviour of the FMSC and its curved mirror variation called the Curved Slats Fixed Mirror Solar Concentrator (CSFMSC), have been analyzed with this tool. A parametric analysis has been carried out in order to determine the influence of the different parameters on the Incidence Angle Modifier (IAM) and to determine the optimal designs at a temperature of 200ºC for three different climates at different latitudes. The theoretical values obtained from the ray-tracing code have been compared with two experimental prototypes. The experimental and numerical results obtained show a good fit. The efficiency curve of one of the prototypes has been determined from the experimental tests. The methodology proposed in the norm EN-12975-2:2006 has been used in combination with IAM values obtained by ray-tracing. It has been shown that this combination can be effectively used to obtain the efficiency curve of complex collectors with a bi-axial IAM model. Advisors/Committee Members: [email protected] (authoremail), true (authoremailshow), Martínez Moll, Víctor (director), true (authorsendemail).

Subjects/Keywords: energía solar, concentrador solar, media temperatura, FMSC, CSFMSC, trazado de rayos, prototipos, caracterización óptica, caracterización térmica, reflector estacionario, foco móvil, calor de procesos, IAM, modificador de ángulo, factorización del IAM, eficiencia óptica, eficiencia térmica, EN-12975-2:2006, energías renovables, método cuasi-dinámico; solar energy, solar concentrator, medium temperature, FMSC, CSFMSC, ray tracing, prototypes, optical characterization, thermal characterization, stationary reflector , mobile focus, process heat, IAM, incidence angle modifier, optical efficiency, thermal efficiency, EN-12975-2:2006, renewable energy, quasi-dynamic method; Enginyeria Mecànica; 53; 62

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Pujol Nadal, R. (2012). Comportamiento Óptico y Térmico de un Concentrador Solar Lineal con reflector estacionario y Foco Móvil. (Thesis). Universitat de les Illes Balears. Retrieved from http://hdl.handle.net/10803/84115

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Pujol Nadal, Ramon. “Comportamiento Óptico y Térmico de un Concentrador Solar Lineal con reflector estacionario y Foco Móvil.” 2012. Thesis, Universitat de les Illes Balears. Accessed December 12, 2018. http://hdl.handle.net/10803/84115.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Pujol Nadal, Ramon. “Comportamiento Óptico y Térmico de un Concentrador Solar Lineal con reflector estacionario y Foco Móvil.” 2012. Web. 12 Dec 2018.

Vancouver:

Pujol Nadal R. Comportamiento Óptico y Térmico de un Concentrador Solar Lineal con reflector estacionario y Foco Móvil. [Internet] [Thesis]. Universitat de les Illes Balears; 2012. [cited 2018 Dec 12]. Available from: http://hdl.handle.net/10803/84115.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Pujol Nadal R. Comportamiento Óptico y Térmico de un Concentrador Solar Lineal con reflector estacionario y Foco Móvil. [Thesis]. Universitat de les Illes Balears; 2012. Available from: http://hdl.handle.net/10803/84115

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

3. Hammer, Kimberly Nicole. Predicting the Performance of a Solar Domestic Water Heating System with Evacuated Tube Collectors and Hydronic Radiant Flooring.

Degree: MS, Mechanical Engineering, 2013, University of Nevada – Las Vegas

Residential solar thermal system installations have been significantly increasing in the last decade and there exists limited resources for reasonably predicting the performance of those systems. A simulated model is developed in MATLAB® and used to predict the performance of a solar domestic water heating system. In the simulated system, hot water is generated using evacuated tube solar collectors and stored in a domestic hot water storage tank, which utilizes immersed coil heat exchangers. The system is designed to provide hydronic radiant floor heating to its occupants based on the heat loss of a building energy model for an energy-efficient home. Performance characteristics of the components from well-known manufacturers are utilized where available. Some of the parameters are easily changeable so that several manufacturers' characteristics could be compared using the model. The system's sensitivity to tank thermal stratification and tank size are investigated. For solar intermittencies, the energy required for auxiliary domestic water heating is determined by the model as well. Some empirical investigations of two sets of evacuated tube collectors were used to compare the validity of the model. Results are presented in terms of temperatures and heat gains. Advisors/Committee Members: Robert Boehm, Woosoon Yim, Yitung Chen, Yahia Baghzouz.

Subjects/Keywords: Dual coil heat exchanger; Dwellings – Energy conservation; Efficiency equation; Energy consumption; Incidence angle modifier; Radiant floor heating; Residential solar thermal; Solar heating; Solar houses; Solar water heaters; System simulation; Thermal stratification; Energy Systems; Mechanical Engineering; Oil, Gas, and Energy; Sustainability

angle. With all solar and collector angles accounted for, the angle of incidence, #, can be… …gives the relationship of the angle of incidence of beam radiation on a tilted surface to all… …other angles defining the sun and that surface. The angle of incidence of beam radiation on a… …of incidence from a tilted surface to the cosine of the zenith angle of the sun at that… …between the transverse and longitudinal incidence angle modifiers (IAM). Carvalho et… 

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Hammer, K. N. (2013). Predicting the Performance of a Solar Domestic Water Heating System with Evacuated Tube Collectors and Hydronic Radiant Flooring. (Masters Thesis). University of Nevada – Las Vegas. Retrieved from https://digitalscholarship.unlv.edu/thesesdissertations/1833

Chicago Manual of Style (16th Edition):

Hammer, Kimberly Nicole. “Predicting the Performance of a Solar Domestic Water Heating System with Evacuated Tube Collectors and Hydronic Radiant Flooring.” 2013. Masters Thesis, University of Nevada – Las Vegas. Accessed December 12, 2018. https://digitalscholarship.unlv.edu/thesesdissertations/1833.

MLA Handbook (7th Edition):

Hammer, Kimberly Nicole. “Predicting the Performance of a Solar Domestic Water Heating System with Evacuated Tube Collectors and Hydronic Radiant Flooring.” 2013. Web. 12 Dec 2018.

Vancouver:

Hammer KN. Predicting the Performance of a Solar Domestic Water Heating System with Evacuated Tube Collectors and Hydronic Radiant Flooring. [Internet] [Masters thesis]. University of Nevada – Las Vegas; 2013. [cited 2018 Dec 12]. Available from: https://digitalscholarship.unlv.edu/thesesdissertations/1833.

Council of Science Editors:

Hammer KN. Predicting the Performance of a Solar Domestic Water Heating System with Evacuated Tube Collectors and Hydronic Radiant Flooring. [Masters Thesis]. University of Nevada – Las Vegas; 2013. Available from: https://digitalscholarship.unlv.edu/thesesdissertations/1833

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