To close the water use budget of irrigated agricultural fields in floodplains with substantial riparian corridors, it is necessary to understand groundwater usage by dominant phreatophytic vegetation, particularly when the primary source of water for irrigation comes from groundwater abstraction. We report here results of estimated evapotranspiration (ET) of a riparian forest, which were based on measurements of sap flow in phreatophytic vegetation within a riparian corridor. The riparian corridor was within a study area 75 to 140 meters wide in the lower portion of the Scotts Creek watershed, which is bounded to the west by the Pacific Ocean in Santa Cruz County, California. Canopy coverage in the study area often approaches 100% during the growing season, with dominant trees being red alder (Alnus rubra Bong.), arroyo willow (Salix lasiolepis Benth.), and pacific willow (Salix lasiandra Benth. var. lasiandra). Other trees include boxelder (Acer negundo L.), bigleaf maple (Acer macrophyllum Pursh.), California bay laurel (Umbellularia californica (Hook. & Arn.) Nutt.), and coastal redwoods (Sequoia sempervirens (D. Don) Endl.). Common understory vegetation includes California blackberry (Rubus ursinus Cham. and Schlecht.), stinging nettle (Urtica dioica subsp. gracilis L.), poison hemlock (Conium maculatum L.), Cape ivy (Delairea odorata Lem.), Italian thistle (Carduus pycnocephalus L. subsp. pycnocephalus), and western poison oak (Toxicodendron diversilobum (Torr. & A. Gray) Greene). We hypothesized that the ET of a riparian forest could be estimated by measuring the sap flow of riparian phreatophytic trees. For the study reported here, only the two most dominant phreatophytic species, namely red alders and arroyo willows, were instrumented with thermal dissipation probes. In addition to diurnal fluctuations, sap flow data collected hitherto also showed expected seasonal variation with summer maxima and winter minima, with transition fall and spring periods. Sap flow measurements from the study area were used to estimate riparian forest ET by projecting them across the canopy areal extent of the riparian forest using sampled tree sapwood areas from six sample plots. The sap flow-based ET results were then compared to ET results reported by two other methods. Additional research, including increased number of trees with thermal dissipation probes, further analysis of sap flow behavior, and continued long-term measurement of sap flow, is needed to further improve the method of using long-term sap flow measurements to estimate the ET of a riparian forest.

No description available.

O uso crescente de irrigação na cafeicultura devido ao cultivo em áreas com maior deficiência hídrica exige conhecimento sobre o consumo de água da cultura. Para contribuir para esse conhecimento, a evapotranspiração global do cafezal (ETc) e sua partição nos fluxos componentes evapotranspiração das linhas de cafeeiros (ETlin), evapotranspiração das entrelinhas (ETel) e a transpiração dos cafeeiros (T) foram determinadas em um cafezal de Coffea arabica cv. Obatã IAC-1669-20, cultivado em Piracicaba, SP, em espaçamento de 3,50 m x 0,90 m, irrigado por gotejamento e idade entre 3 a 4 anos, com medidas de setembro/04 a maio/05 e em setembro e outubro de 2005. ETc foi determinada pelo método de balanço de energia-razão de Bowen, ETlin por lisímetros de células de carga, sendo estes usados em vários períodos com o solo coberto com plástico para determinação direta da transpiração e para calibrar o método da sonda de dissipação térmica, usado na determinação do fluxo de seiva (FS) dos cafeeiros. Em abril-maio/05, FS foi usado como uma estimativa de T diária. ETc e componentes foram relacionados com a evapotranspiração de referência estimada pelos métodos de Penman- Monteith (ETo 1) e do tanque classe A (ETo 2). O calor latente de vaporização (LE) representou a maior fração na partição da energia disponível (saldo de radiação menos fluxo de calor no solo), com variação de 73 a 80 % ao longo dos meses, não se podendo descartar a contribuição de calor advectivo para os valores encontrados nos meses secos. ETc cresceu a partir de setembro/04 a fevereiro/05 (2,75 a 4,58 mm d-1), refletindo principalmente o incremento de área foliar e diminuindo, posteriormente, até maio/05 (3,13 mm d-1) com a diminuição da demanda atmosférica. Em setembro-outubro/05 os valores foram maiores (2,93 e 4,29 mm d-1) do que os observados no mesmo período em 2004, sendo o aumento da área foliar uma das responsáveis pelo fato. A relação ETc/ETo ("Kc global da cultura") foi maior quando calculada com ETo 1 do que com ETo 2, sendo os valores crescentes até janeiro/05 (1,20 com ETo 1 e 1,21 com ETo 2) mas com o menor valor em setembro/04 (0,67 e 0,54) e com diminuição da tendência de acréscimo em fevereiro/05 (1,17 e 0,73), provavelmente pela regulação estomática dos cafeeiros devido à alta demanda atmosférica nesses meses. A contribuição de ETlin para a ETc variou pouco entre setembro/04 e fevereiro/05 (24 % a 31 %), aumentando em março e abril (35 % e 40 %), valores esses próximos da proporção entre a área de solo coberta pelos cafeeiros e a área total (linhas+entrelinhas). A relação ETlin/ETo variou entre 0,20 (uso de ETo 1) e 0,16 (com ETo 2) em setembro/04 a 0,36-0,47 (com ETo 1) e 0,25-0,49 nos outros meses. A T dos cafeeiros por unidade de área foliar diminuiu com o aumento da área foliar. A relação T/ETlin variou de 72 % em fevereiro a 46 % em abril, sendo o valor de T/ETo ("Kc basal") variável entre 0,13 (com ETo 1) e 0,10 (com ETo 2) em setembro a 0,30 (independente do método de estimativa de ETo) em abril e maio/04, provavelmente refletindo a menor atividade fisiológica. / The increasing use of irrigation in coffee plantations in Brazil, due to the deplacement of the crop to areas where water deficit occurs, requires knowledge about crop water consumption. Aiming to know more about coffee plantation water consumption, daily crop evapotranspiration (ETc) and its partition in row evapotranspiration (ETrow), interrows evapotanspiration (ETint) and coffee plants transpiration (T) were determined in a drip-irrigated coffee plantation (cv. Obatã IAC-1669-20), cultivated at 3.5 m between rows and 0.9m between plants, in Piracicaba, São Paulo State, Brazil. The ET and wheater variables measurements were carried out from September 2004 to May 2005 and from September to October 2005. ETc was determined by he Bowen ratio-energy balance method, ETrow by load cell lysimeters and T with lysimeters with soil surface covered with plastic or by sap flow determined with the thermal dissipation probe method (TDP). Lysimeters were also used to calibrate the TDP method. So, sap flow was adopted as representative of coffee plants transpiration for 24-h period. ET and its components were related to the reference evapotranspiration, determined by Penman-Monteith (ETo 1) and Class-A pan (ETo 2) methods. Latent heat of vaporization (LE) represented the major fraction (73 a 80 %) of the available energy (net radiation less soil heat flux) along the months, but a contribution of advective heat flux in dry months must be considered for the observed values. ETc increased from September 2004 to February 2005 (from 2.75 to 4.58 mm d-1), which is reflecting the increase of coffee plants leaf area. From March to May 2005, ETc decreased according to the decrease of the atmospheric demand. In September and October 2005, ETc were greater, respectively, 2.93 and 4.29 mm d-1, than those observed in the same months of 2004 and, again the increase of leaf area was the responsable for these differences. ETc/ETo, defined as a "global Kc", was greater when determined with ETo 1 than when determined with ETo 2, increasing with the leaf area.from September 2004 (0.67 with ETo 1 and 0.54 with ETo 2) to January 2005 (1,20 and 1,21). In February Kc decreased to 1.17 (with ETo 1) and 0.73 (with ETo 2), probably as a consequence of the coffee plants stomatal control due to the high atmospheric demand. The contribution of ETrow to ETc varied between 25 % and 31 % for the period September 2004- February 2005, increasing in March and April 2005 (35 % and 40 %). These values were close to those observed for the ratio between the area of soil covered by coffee plants and the total area (rows+interrows). ETlin/ETo changed from 0.20 or 0.16 (using ETo 1 and ETo 2, respectively) in September 2004 to 0.36-0.47 (with ETo 1) or 0.25- 0.49 (with ETo 2) in the other months. Coffee plant transpiration per leaf area unit decresead with the increase of leaf area. T/ETrow changed from 0.72 (February) to 0.46 (April). T/ETo ("basal Kc") ranged from 0.13 (with ETo 1) or 0.10 (with ETo 2) in September 2004 to 0.30 (for both ETo 1 or ETo 2) in February, but decreased in April and May 2005, probably reflecting the decrease in the physiological activity of coffee plants.

Submitted by Maicon Juliano Schmidt (maicons) on 2015-03-20T19:50:03Z No. of bitstreams: 1 000002F2.pdf: 1101205 bytes, checksum: 35ea0ac880e5841836ff1b5e64d2f9ff (MD5) / Made available in DSpace on 2015-03-20T19:50:04Z (GMT). No. of bitstreams: 1 000002F2.pdf: 1101205 bytes, checksum: 35ea0ac880e5841836ff1b5e64d2f9ff (MD5) Previous issue date: 2012-11-27 / CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico / Componentes eletrônicos estão cada vez mais potentes, necessitando de dissipações térmicas maiores. Os ventiladores atuais, conhecidos comercialmente como "coolers", estão se tornando ineficientes para esta evolução por dependerem de uma maior vazão para atender a demanda de calor dissipado, o que também causa aumento no seu ruído. Como uma alternativa para aprimorar a troca de calor, estudam-se (micro) jatos sintéticos. Estes são produzidos através de uma cavidade selada por uma membrana oscilatória e uma placa com um orifício. A movimentação periódica da membrana produz um jato com valor positivo de quantidade de movimento, que pode ser direcionado para o resfriamento de um dispositivo eletrônico.Para análise térmica, um modelo numérico do dispositivo de refrigeração foi construído em ANSYS CFX 12.0. Variações nos números de Reynolds e Strouhal dos jatos sintéticos e posição da região aquecida na superfície de interesse foram realizadas e seu efeito no desempenho térmico analisado. Os resultados foram comparados a um escoamento convencional de mesma geometria em regime permanente e submetido à mesma vazão mássica média induzida por cada jato sintético. Para a configuração testada, observou-se que os (micro) jatos sintéticos podem fornecer um fluxo de ar mais direcionado para os "hotspots" com maior necessidade de resfriamento. Os resultados encontrados indicam um aumento de número de Nusselt até 122% em jatos sintéticos comparados aos escoamentos contínuos. Logo, confirmam o maior desempenho térmico do jato sintético em relação ao método convencional equivalente e justificam a necessidade de investigações adicionais nesta área. Isto indica que os jatos sintéticos podem ser personalizados ou direcionados especificamente para atender a demanda de resfriamento do problema de interesse. / The rising power consumption of electronic components requires higher and higher thermal dissipation. Current fan systems, commercially known as "coolers", are becoming ineffective to cope with this demand since their performance is dependent on the volumetric flow rate of the driving fan, which becomes more wasteful and noisy. An alternative to improve the heat exchange of current systems is the application of (micro) synthetic jets. These are produced by the oscillations in a cavity bounded by a membrane and a plate with an orifice. Membrane actuation produces a net forward momentum jet through the orifice, which can be applied to cool an electronic device. For this analysis, a numerical model of the cooling device was built on ANSYS CFX 12.0. Variations in jet Reynolds and Strouhal numbers and positioning of the heated region of interest were made and their effect on thermal performance analyzed. Results were compared to a conventional flow with the same geometry but subjected to a single-fan providing steady flow with the same average mass flow rate induced by each synthetic jet. For the configurations tested, it was found that (micro) synthetic jets may provide more directed air flow for "hotspots" with the greatest need of cooling. The results indicate a thermal performance up to 122% higher compared to their equivalent conventional cooling case. This confirmation of the higher thermal performance of synthetic jets relative to a convencional method and justifies the need for the current and additional investigations in this area. Results also indicate that synthetic jets can be customized and specifically directed to meet the cooling demand of the problem in question.

Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2015-07-08T14:34:31Z No. of bitstreams: 1 Matheus Vicenzo Lehnen.pdf: 7507080 bytes, checksum: 1036a30adcb3840ea0e5fcb545f29987 (MD5) / Made available in DSpace on 2015-07-08T14:34:31Z (GMT). No. of bitstreams: 1 Matheus Vicenzo Lehnen.pdf: 7507080 bytes, checksum: 1036a30adcb3840ea0e5fcb545f29987 (MD5) Previous issue date: 2012-05 / Milton Valente / Nos dias atuais, os componentes eletrônicos estão cada vez mais potentes e com mais dispositivos integrados e há a necessidade de uma dissipação térmica mais eficiente. Os atuais ventiladores e dissipadores de calor usando ar como fluido de trabalho estão ficando obsoletos. Por este motivo, torna-se necessário o desenvolvimento de um sistema mais eficiente. Existem três técnicas principais em estudo nesta área: resfriamento líquido, trocadores de calor compostos por microcanais e jatos sintéticos como transmissores de quantidade de movimento ao fluido. Entretanto, a análise em pequena escala encontra limitações experimentais de modo que uma abordagem por Dinamica de Fluidos Computacional (Computational Fluid Dynamics – CFD) é mais recomendável para caracterizar e validar o desempenho dos jatos sintéticos. O objetivo principal deste trabalho é realizar uma análise fluidodinâmica de jatos sintéticos e caracterizar a troca térmica de jatos sintéticos colidindo sobre uma superfície aquecida, através de simulação numérica. A flexibilidade da aproximação numérica também possibilita o estudo da sensibilidade do design a vários parâmetros físicos e geométricos, tais como o número de Reynolds, a frequência do atuador, o número de Prandtl, a distância da placa aquecida ao orifício da cavidade, o formato do orifício do atuador, a profundidade da cavidade e a espessura da placa do orifício. Os resultados caracterizam o efeito dos parâmetros físicos e geométricos de interesse na formação do jato e na dissipação térmica. O conhecimento agregado neste estudo permitiu determinar uma correlação para o número de Nusselt em função da frequência adimensional – o número de Strouhal – do número de Reynolds, do número de Prandtl e da distância adimensional da superfície aquecida ao orifício. Assim, é possível prever o comportamento de tais jatos sobre a superfície aquecida, e assim contribuir para os atuais estudos nesta linha de pesquisa. Os resultados apresentados tem então aplicação em estudos posteriores, de maior complexidade de design com atuadores combinados com trocadores de calor de aletas, coolers e micro canais, resultando em avanços na área de resfriamento de microchips. / Current electronic components are becoming ever more potent and densly integrated, which requires further increases in the efficiency of heat dissipation. With current fan-based heat dissipation techniques with air as the working fluid becoming outdated, there is a pressing need to develop more eficient methods to cope with demand. So far, three techniques have been the primary focus of studies in this area: liquid cooling, microchannel heat exchangers and synthetic jets used to promote increased momentum transfer. Analysis of such devices at the small physical scale of electronic components is somewhat problematic in experimental form so that a computational fluid dynamics (CFD) approach is recommended. The main objective of this study is thus to utilize a CFD approach to establish the performance characteristics of a synthetic jet impacting against a heated surface. The flexibility of a numerical approach also allows the examination of the sensibility of the design with respect to several physycal and geometric parameters such as Reynolds number, pulsing frequency, jet orifice shape and size, cavity size and distance between the heated surface and the device. Such results, provide insight in the effect of physical and geometric parameters in the jet formation and heat dissipation. The combined knowledge of this study allowed the development of a practical correlation for the Nusselt number based on the Strouhal number (normalized pulsing frequency), Reynolds number, Prandtl number and the distance between the heated surface and the synthetic jet. This result allows improved predictions of a jet impacting against a heated surface and, consequently, adds an important contribution to other studies in this area. It is expected that the results presented here will be the starting point for further work, in which increasingly complex geometries such as actuators combined with heat exchangers equipped with fins, coolers or microchannels are examined to further improve the knowledge in the field of electronic cooling.

O uso crescente de irrigação na cafeicultura devido ao cultivo em áreas com maior deficiência hídrica exige conhecimento sobre o consumo de água da cultura. Para contribuir para esse conhecimento, a evapotranspiração global do cafezal (ETc) e sua partição nos fluxos componentes evapotranspiração das linhas de cafeeiros (ETlin), evapotranspiração das entrelinhas (ETel) e a transpiração dos cafeeiros (T) foram determinadas em um cafezal de Coffea arabica cv. Obatã IAC-1669-20, cultivado em Piracicaba, SP, em espaçamento de 3,50 m x 0,90 m, irrigado por gotejamento e idade entre 3 a 4 anos, com medidas de setembro/04 a maio/05 e em setembro e outubro de 2005. ETc foi determinada pelo método de balanço de energia-razão de Bowen, ETlin por lisímetros de células de carga, sendo estes usados em vários períodos com o solo coberto com plástico para determinação direta da transpiração e para calibrar o método da sonda de dissipação térmica, usado na determinação do fluxo de seiva (FS) dos cafeeiros. Em abril-maio/05, FS foi usado como uma estimativa de T diária. ETc e componentes foram relacionados com a evapotranspiração de referência estimada pelos métodos de Penman- Monteith (ETo 1) e do tanque classe A (ETo 2). O calor latente de vaporização (LE) representou a maior fração na partição da energia disponível (saldo de radiação menos fluxo de calor no solo), com variação de 73 a 80 % ao longo dos meses, não se podendo descartar a contribuição de calor advectivo para os valores encontrados nos meses secos. ETc cresceu a partir de setembro/04 a fevereiro/05 (2,75 a 4,58 mm d-1), refletindo principalmente o incremento de área foliar e diminuindo, posteriormente, até maio/05 (3,13 mm d-1) com a diminuição da demanda atmosférica. Em setembro-outubro/05 os valores foram maiores (2,93 e 4,29 mm d-1) do que os observados no mesmo período em 2004, sendo o aumento da área foliar uma das responsáveis pelo fato. A relação ETc/ETo (“Kc global da cultura”) foi maior quando calculada com ETo 1 do que com ETo 2, sendo os valores crescentes até janeiro/05 (1,20 com ETo 1 e 1,21 com ETo 2) mas com o menor valor em setembro/04 (0,67 e 0,54) e com diminuição da tendência de acréscimo em fevereiro/05 (1,17 e 0,73), provavelmente pela regulação estomática dos cafeeiros devido à alta demanda atmosférica nesses meses. A contribuição de ETlin para a ETc variou pouco entre setembro/04 e fevereiro/05 (24 % a 31 %), aumentando em março e abril (35 % e 40 %), valores esses próximos da proporção entre a área de solo coberta pelos cafeeiros e a área total (linhas+entrelinhas). A relação ETlin/ETo variou entre 0,20 (uso de ETo 1) e 0,16 (com ETo 2) em setembro/04 a 0,36-0,47 (com ETo 1) e 0,25-0,49 nos outros meses. A T dos cafeeiros por unidade de área foliar diminuiu com o aumento da área foliar. A relação T/ETlin variou de 72 % em fevereiro a 46 % em abril, sendo o valor de T/ETo (“Kc basal”) variável entre 0,13 (com ETo 1) e 0,10 (com ETo 2) em setembro a 0,30 (independente do método de estimativa de ETo) em abril e maio/04, provavelmente refletindo a menor atividade fisiológica. / The increasing use of irrigation in coffee plantations in Brazil, due to the deplacement of the crop to areas where water deficit occurs, requires knowledge about crop water consumption. Aiming to know more about coffee plantation water consumption, daily crop evapotranspiration (ETc) and its partition in row evapotranspiration (ETrow), interrows evapotanspiration (ETint) and coffee plants transpiration (T) were determined in a drip-irrigated coffee plantation (cv. Obatã IAC-1669-20), cultivated at 3.5 m between rows and 0.9m between plants, in Piracicaba, São Paulo State, Brazil. The ET and wheater variables measurements were carried out from September 2004 to May 2005 and from September to October 2005. ETc was determined by he Bowen ratio-energy balance method, ETrow by load cell lysimeters and T with lysimeters with soil surface covered with plastic or by sap flow determined with the thermal dissipation probe method (TDP). Lysimeters were also used to calibrate the TDP method. So, sap flow was adopted as representative of coffee plants transpiration for 24-h period. ET and its components were related to the reference evapotranspiration, determined by Penman-Monteith (ETo 1) and Class-A pan (ETo 2) methods. Latent heat of vaporization (LE) represented the major fraction (73 a 80 %) of the available energy (net radiation less soil heat flux) along the months, but a contribution of advective heat flux in dry months must be considered for the observed values. ETc increased from September 2004 to February 2005 (from 2.75 to 4.58 mm d-1), which is reflecting the increase of coffee plants leaf area. From March to May 2005, ETc decreased according to the decrease of the atmospheric demand. In September and October 2005, ETc were greater, respectively, 2.93 and 4.29 mm d-1, than those observed in the same months of 2004 and, again the increase of leaf area was the responsable for these differences. ETc/ETo, defined as a “global Kc”, was greater when determined with ETo 1 than when determined with ETo 2, increasing with the leaf area.from September 2004 (0.67 with ETo 1 and 0.54 with ETo 2) to January 2005 (1,20 and 1,21). In February Kc decreased to 1.17 (with ETo 1) and 0.73 (with ETo 2), probably as a consequence of the coffee plants stomatal control due to the high atmospheric demand. The contribution of ETrow to ETc varied between 25 % and 31 % for the period September 2004- February 2005, increasing in March and April 2005 (35 % and 40 %). These values were close to those observed for the ratio between the area of soil covered by coffee plants and the total area (rows+interrows). ETlin/ETo changed from 0.20 or 0.16 (using ETo 1 and ETo 2, respectively) in September 2004 to 0.36-0.47 (with ETo 1) or 0.25- 0.49 (with ETo 2) in the other months. Coffee plant transpiration per leaf area unit decresead with the increase of leaf area. T/ETrow changed from 0.72 (February) to 0.46 (April). T/ETo (“basal Kc”) ranged from 0.13 (with ETo 1) or 0.10 (with ETo 2) in September 2004 to 0.30 (for both ETo 1 or ETo 2) in February, but decreased in April and May 2005, probably reflecting the decrease in the physiological activity of coffee plants.

Native plant communities and agricultural land are commonly converted to urban areas as cities across the Western United States continue to grow and expand. This expansion is typically accompanied by afforestation where a common goal among communities is to maximize shade tree composition. Planted forests in these regions are commonly composed of introduced tree species native to mesic environments and their ability to persist is dependent on consistent irrigation inputs. Many potential ecosystem services may be derived from planting trees in urban and suburban areas; however, there are also costs associated with extensive afforestation, and shade tree cover may have significant implications on municipal water budgets. In this study I evaluate variation in daily and seasonal water use of regionally common suburban landscape tree species in the Heber Valley (Wasatch County, Utah). I had two primary objectives: (1) to identify and understand the differences in transpiration between landscape tree species in a suburban setting and (2) to assess the sensitivity of sap flux and transpiration to variation in vapor pressure deficit, wind speed, and incoming shortwave radiation. I used Granier's thermal dissipation method to measure the temperature difference (ΔT) between two sap flux probes. The empirical equation developed by Granier was used to convert ΔT into sap flux density (Jo) measurements, which were then scaled to whole-tree transpiration. There were consistent and substantial differences in sap flux between tree species. I found that Picea pungens under irrigated growing conditions, on average, had Jo rates that were 32% greater and whole tree water use (ET) rates that were 550% greater than all other species studied. The findings of Jo may be partially explained by xylem architecture and physiological control over stomatal aperture. However, the rate of water flux in the outermost portion of sapwood does not necessarily determine the magnitude of whole tree transpiration. Rather, ET in this study was largely explained by the combined effects of irrigation, tree size, and sapwood to heartwood ratio.

Ce travail s'inscrit dans le domaine des cellules solaires organiques et se focalise sur le dimensionnement et design de la cellule. Nous avons cherché à établir la relation entre la forme d'une cellule solaire et sa dissipation thermique dans les électrodes, plus spécifiquement l'électrode inférieure transparente, car les matériaux utilisés pour la réaliser ont souvent une conductivité très faible par rapport à celle des électrodes métalliques. D'autre part nous présentons un modèle actif capable de simuler le comportement de la couche active selon différentes conditions d'éclairage (illumination partielle et défauts localisés) et pour différents régimes de fonctionnement (injection, polarisation). Dans le cadre du projet PHASME en partenariat avec Disasolar et l'INES, on a posé les bases pour le développement d'un logiciel de conception capable de réaliser un module solaire multicolore à partir d'un substrat de forme géométrique quelconque. On a identifié deux types d'algorithme. Une solution A (dite matricielle), pour laquelle on effectue le remplissage de la surface active du module avec des cellules identiques, relie entre elles ces cellules en sous-groupes pour créer le potentiel de fonctionnement souhaité. Une méthode B (dite non-matricielle) consiste à partager la surface du module en sous-modules de surface quelconque adaptée aux zones de couleur. Ces sous-modules sont ensuite découpés en groupement en série cellules du même type (couleur, performance, matériaux de couche active), mais dont la forme s'adapte exactement au remplissage du sous-module. Ces cellules doivent nécessairement avoir la même surface, afin de produire le même courant pour éviter les pertes dans le groupement en série. / This work concerns organic solar cells and it focuses on several aspects of the design of the device that are related to the sizing. The core of this study highlights the relation between the shape of an organic solar cell and the thermal dissipation inside the electrodes. The main contribution to this power loss comes from the transparent back electrode, since its conductivity is typically lower than those of the top electrode. In parallel we developed a non-linear model for the active layer in order to simulate the behavior of the solar cells in several particular illumination cases (such as spotlights, shadows and defects in the active layer) and different working regime. In the framework of PHASME project, a grant in collaboration with Disasolar and CEA-INES, we developed another piece of software closer to the CAD domain which the main function was to create a photovoltaic polychrome module starting from a substrate with given shape and size. We found two strategies. One consists in filling by the same solar cell shape and size the entire substrate and then in finding a suitable grouping in order to have the correct working point outside the device (matrix approach). The other one (non-matrix approach) consists in adapting the shape of the device to a given colored region, each individual cell keeping the same surface extension, which allows them to be connected in series since they all generate the same amount of current.