No description available.

Made available in DSpace on 2014-06-11T19:24:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-27Bitstream added on 2014-06-13T19:11:22Z : No. of bitstreams: 1 inacio_t_me_botfca.pdf: 488409 bytes, checksum: f07ac54da8077b5df98e78bea1785b2e (MD5) / No presente trabalho é apresentado o estudo do potencial da energia solar disponível no município de Botucatu, através das análises das séries temporais médias anuais diárias, médias mensais diárias e séries anuais dos acumulados mensais das radiações global, difusa e direta na horizontal do período de 1996 à 2005. As irradiações, em MJ/m2, foram calculadas a partir das integrações diárias das irradiâncias global , irradiância difusa , irradiância direta na horizontal e no topo da atmosfera , determinando-se as irradiações diárias: , e ; e médias mensais: G I d I D I O I dG H d d H dD H dGH , d d H e dD H . A partir das médias mensais, determinou-se o índice de claridade t K (razão da irradiação global pela do topo da atmosfera), e as demais frações das radiações: d K (razão da irradiação difusa pela global), ′ d K (razão da irradiação difusa pela do topo da atmosfera), D K (razão da irradiação direta pela global), ′ D K (razão da irradiação direta pela do topo da atmosfera). Realizou-se uma análise estatística dos dados de radiação solar, de forma a se obter os valores médios, desvios, máximos, mínimos, variação e acumulados, mensais e anuais. E apresentaram-se de forma gráfica os resultados estatísticos obtidos para compará-los com os valores médios mensais diários da precipitação, nebulosidade e insolação, para que se possam explicar os fenômenos que causam as variações nos valores da série temporal de radiação solar na superfície terrestre de Botucatu. Os valores médios mensais diários da radiação global variaram de 21,0 MJ/m² em novembro até 12,6 MJ/m² em junho. A fração t K media anual foi de 53,0%. Os valores médios mensais diários da radiação difusa variaram de 10,0 MJ/m² em dezembro... / The present work presents the potential of solar energy available in the city of Botucatu, by analyzing time series of annual average daily, monthly averages of daily and cumulative monthly series of annual global radiation, diffuse and horizontal direct in the period of 1996 to 2005. The irradiation in MJ/m2 were calculated from daily integrations of the global irradiance , diffuse irradiance , horizontal direct irradiance and at the top of the atmosphere , by providing daily the daily irradiation: , and ; and monthly averages: G I d I D I O I dG H d d H dD H dG H , d d H and dD H . From the monthly averages, it was determined the clearness index t K (global/top of the atmosphere irradiation), and other fractions of radiation: d K (diffuse/global irradiation), ′ d K (diffuse/top of the atmosphere irradiation), D K (direct/global irradiation), ′ D K (direct/top of the atmosphere irradiation). Was held a statistical analysis of data on solar radiation in order to obtain the average values, deviation, minimum, maximum, variation and cumulative, monthly and yearly. And it showed in graphic statistical results obtained to compare them with the monthly average daily values of precipitation, cloudiness and sunshine, so that can explain the phenomena that cause variation in te values of time series of solar radiation on the Earth's surface of Botucatu. The values daily monthly average global radiation varied from 21.0 MJ/m² in november to 12,6 MJ/m² in june. The average annual t K fraction was 53,0%. The values daily monthly average diffuse radiation varied from 10,0 MJ/m² in december to 3,7 MJ/m² in june. The average annual d K fraction was 37% and the average annual ′ d K fraction was 19,7%. The values daily average monthly direct radiation varied from 11,8 MJ/m² in november... (Complete abstract click electronic access below)

Resumo: No presente trabalho é apresentado o estudo do potencial da energia solar disponível no município de Botucatu, através das análises das séries temporais médias anuais diárias, médias mensais diárias e séries anuais dos acumulados mensais das radiações global, difusa e direta na horizontal do período de 1996 à 2005. As irradiações, em MJ/m2, foram calculadas a partir das integrações diárias das irradiâncias global , irradiância difusa , irradiância direta na horizontal e no topo da atmosfera , determinando-se as irradiações diárias: , e ; e médias mensais: G I d I D I O I dG H d d H dD H dGH , d d H e dD H . A partir das médias mensais, determinou-se o índice de claridade t K (razão da irradiação global pela do topo da atmosfera), e as demais frações das radiações: d K (razão da irradiação difusa pela global), ′ d K (razão da irradiação difusa pela do topo da atmosfera), D K (razão da irradiação direta pela global), ′ D K (razão da irradiação direta pela do topo da atmosfera). Realizou-se uma análise estatística dos dados de radiação solar, de forma a se obter os valores médios, desvios, máximos, mínimos, variação e acumulados, mensais e anuais. E apresentaram-se de forma gráfica os resultados estatísticos obtidos para compará-los com os valores médios mensais diários da precipitação, nebulosidade e insolação, para que se possam explicar os fenômenos que causam as variações nos valores da série temporal de radiação solar na superfície terrestre de Botucatu. Os valores médios mensais diários da radiação global variaram de 21,0 MJ/m² em novembro até 12,6 MJ/m² em junho. A fração t K media anual foi de 53,0%. Os valores médios mensais diários da radiação difusa variaram de 10,0 MJ/m² em dezembro... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract : The present work presents the potential of solar energy available in the city of Botucatu, by analyzing time series of annual average daily, monthly averages of daily and cumulative monthly series of annual global radiation, diffuse and horizontal direct in the period of 1996 to 2005. The irradiation in MJ/m2 were calculated from daily integrations of the global irradiance , diffuse irradiance , horizontal direct irradiance and at the top of the atmosphere , by providing daily the daily irradiation: , and ; and monthly averages: G I d I D I O I dG H d d H dD H dG H , d d H and dD H . From the monthly averages, it was determined the clearness index t K (global/top of the atmosphere irradiation), and other fractions of radiation: d K (diffuse/global irradiation), ′ d K (diffuse/top of the atmosphere irradiation), D K (direct/global irradiation), ′ D K (direct/top of the atmosphere irradiation). Was held a statistical analysis of data on solar radiation in order to obtain the average values, deviation, minimum, maximum, variation and cumulative, monthly and yearly. And it showed in graphic statistical results obtained to compare them with the monthly average daily values of precipitation, cloudiness and sunshine, so that can explain the phenomena that cause variation in te values of time series of solar radiation on the Earth's surface of Botucatu. The values daily monthly average global radiation varied from 21.0 MJ/m² in november to 12,6 MJ/m² in june. The average annual t K fraction was 53,0%. The values daily monthly average diffuse radiation varied from 10,0 MJ/m² in december to 3,7 MJ/m² in june. The average annual d K fraction was 37% and the average annual ′ d K fraction was 19,7%. The values daily average monthly direct radiation varied from 11,8 MJ/m² in november... (Complete abstract click electronic access below) / Orientador: João Francisco Escobedo / Coorientador: Eduardo Nardini Gomes / Banca: Dinival Martins / Banca: Alexandre Dal Pai / Mestre

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.