Analysis of a Hybrid Solar Collector Photovoltaic Thermal (PVT)

AbstractA solar hybrid photovoltaic thermal (PVT) is a set of combined solar collector, which consists of a photovoltaic module (PV) for the conversion of electrical energy and solar plan for the high efficiency thermal energy conversion, in the same frame.An attempt made to analyze the hybrid solar collector using Computational Fluid Dynamics (CFD) to simulate the PVT solar collector to a better understanding of heat transfer capabilities in this type of systems. In the present work, the fluid flow and heat transfer in the module are studied using the ANSYS14 software. The heat transfer phenomenon conjugate between the photovoltaic cells and the coolant is modeled using the FLUENT software. The transfer of heat by the solar radiation is not modeled; however, the effects of radiation are taken for consideration when calculating the conditions for heat flux limit for the collector region. The geometric model and fluid domain for the CFD analysis is generated using ANSYS software DesingModeler, mesh geometry is carried out by ANSYS Meshing Software

Investigation, Analysis and Optimization of PEMFC Channel Cross-Section Shape

In this study, a three-dimensional (CFD) model is employed to simulate and optimize the CCS (Channel Cross-Section) shape of the single straight channel PEMFC. Four CCS shapes, namely trapeze, inverted trapeze, half of ellipse and inverted half of ellipse, are investigated using ANSYS-FLUENT software and compared to the rectangular and triangular CCS shapes. The results obtained from the simulation are compared to the experimental results of the literature. A good agreement is observed between the numerical and experimental results. From the obtained results, it appears that the best delivered power density is reported by the trapeze CCS configuration, whereas, the worst delivered power density is obtained by the inverted half of ellipse CCS configuration. The highest pressure-drop and pumping power are obtained with the triangular CCS configuration and the smallest are resulted by the rectangular CCS configuration. Finally, the highest net power output is reported by the trapeze channel cross-section configuration, while, the lowest one is yielded by the inverted half of ellipse CCS configuration

Etude des transferts de chaleur et de masse dans un silo a grains soumis a un flux de chaleur parietal instationnaire

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Performance analysis of AS-SOFC fuel cell combining single and sinusoidal flow field: numerical study

The performance of a solid oxide fuel cell (SOFC) was examined using 3D computational fluid dynamics to model mass and heat flows inside the channels. In the present investigation, a SOFC fuel cell with a new flow field based on a sinusoidal flow has been studied. The latter was tested and compared with a single flow using ANSYS FLUENT. The obtained results showed that at a given operating voltage, the maximum power for the sinusoidal and the single flow fields were 1.43 and 1.35 W/cm2, respectively. By taking in addition, into account the concentration, activation and Ohmic losses; it was noticed that the distribution of velocity and temperature for the sinusoidal flow led to bettered results. Furthermore, it was observed that the maximum use of H2 mass fraction consumed in sinusoidal and single flow field designs were 60% and 55% respectively. Similarly, the highest H2O mass fraction values produced for the sinusoidal and single flow designs were 42% and 34% respectively. This model was validated and confronted to previous data. The present results agree well with reported studies in literature

Performance analysis of AS-SOFC fuel cell combining single and sinusoidal flow field: numerical study

The performance of a solid oxide fuel cell (SOFC) was examined using 3D computational fluid dynamics to model mass and heat flows inside the channels. In the present investigation, a SOFC fuel cell with a new flow field based on a sinusoidal flow has been studied. The latter was tested and compared with a single flow using ANSYS FLUENT. The obtained results showed that at a given operating voltage, the maximum power for the sinusoidal and the single flow fields were 1.43 and 1.35 W/cm2, respectively. By taking in addition, into account the concentration, activation and Ohmic losses; it was noticed that the distribution of velocity and temperature for the sinusoidal flow led to bettered results. Furthermore, it was observed that the maximum use of H2 mass fraction consumed in sinusoidal and single flow field designs were 60% and 55% respectively. Similarly, the highest H2O mass fraction values produced for the sinusoidal and single flow designs were 42% and 34% respectively. This model was validated and confronted to previous data. The present results agree well with reported studies in literature

Natural Convection in Tilted Rectangular Cavity subjected to T

The present study investigates the spectral analysis for natural convection in a tilted rectangular cavity, lled with high Prandtl oil ”Pr =880” by the code CFD. A constant vertical temperature gradient has been performed by subjecting the horizontal walls to constant temperatures Th and Tc; respectively. Other walls are adiabatic except the left small sidewall is differentially heating with temperature TA creating the horizontal temperature gradient. The results are presented for different values of lateral heating and inclination angle. The spectral analysis is used to identify and show effects on the original oscillation of the natural convection by the various investigated parameters (TA and θ)

La gestion thermique dans les piles à combustible PEMFC

International audienceDans la pile à combustible à membrane échangeuse de protons PEMFC, certaines difficultés techniques restent à surmonter pour convaincre les principaux acteurs de l'intérêt du développement d'une économie de l'hydrogène, tels que la gestion de la chaleur et de l'eau dans la cellule, le module de stack et le système de cette pile PEMFC. En réalité, les piles à combustible sont formées d'un empilement de cellules élémentaires (stack) connectées en série afin d'obtenir des puissances plus élevées. Les stacks peuvent être composés au maximum d'une centaine de cellules, une augmentation du nombre de cellules engendre des difficultés pour la gestion thermique. Cet article présente une approche électrochimique pour comprendre la cinétique d'échauffement qui est trop important dans certaines parties (régions) de la pile et pour réduire les contraintes thermiques manifestées

Hydrogen consumption and power density in a co-flow planar SOFC

International audienceIn the present work, power density and hydrogen consumption in a co-flow planar solid oxide fuel cell (SOFC) are studied according to the inlet functional parameters; such as the operational temperature, the operational pressure, the flow rates and the mass fractions of the species. Furthermore, the effect of the cell size is investigated. The results of a zero and a one-dimensional numerical electro-dynamic model predict the remaining quantity of the fed hydrogen at the output of the anode flow channel. The remaining hydrogen quantities and the SOFC's power density obtained are discussed as a function of the inlet functional parameters, the geometrical configuration of the cell and several operating cell voltages values