4. ANÁLISIS E INTERPRETACIÓN DE RESULTADOS
4.4. RESUMEN DE LOS APRENDIZAJES ALCANZADOS POR LOS ESTUDIANTES EN
Despite the rapid growth of photovoltaic (PV) power stations over the last decade, there are not yet sufficient studies to investigate the effect of wind on the loading of the ground mounted solar PV panel. As a result, national building codes around the world, lack the provision for minimum design loads for ground mounted solar PV panels either in stand- alone or array configuration. It is also of paramount importance to study the aerodynamic flow mechanisms around the solar panel in detail since these flow features are generating the wind loads. Another effect of wind on the solar panel is the heat transfer from the panel surface. As pointed out by Skoplaki and Palyvos (2009), wind induced heat transfer can significantly affect the electrical efficiency of PV panels. Hence, correlations between heat transfer and wind flow around ground mounted solar panels need to be developed.
Therefore the specific objectives of this study are:
To estimate wind loads on ground mounted solar panels in both stand- alone and array configuration.
To develop the relation between convective heat transfer from the surfaces of ground mounted solar panels and wind speed.
To analyze the wind flow structures around the solar panel in relation to both wind loads and heat transfer.
To establish numerical modelling approaches for simulating wind effects (loading and heat transfer) on ground mounted solar panels in atmospheric boundary layer flows.
This research is pertained to better understand the effect of wind on aerodynamic loads and heat transfer for ground mounted solar panels. The accomplishment of the aforementioned goals of this research would facilitate the advancement in better planning and designing of ground mounted solar panel based utility scale PV power stations. In this regard, the research conducted in this thesis aims to:
Determine the mean aerodynamic wind loads on ground mounted solar panels in both stand-alone and array configuration under varying wind directions using unsteady 3D Reynolds-Averaged Navier-Stokes (RANS) simulations.
Experimentally determine the wind flow around a stand-alone ground mounted solar panel using wind tunnel tests with Particle Image Velocimetry (PIV). Also explore the wake behavior employing Hot Wire Anemometry (HWA). Establish an experimental data base for future numerical studies related to ground mounted PV panels.
Develop a numerical modelling approach with an open source software package OpenFOAM (ESI Group) and validation of the modelling approach based on the above experimental results.
Evaluate the convective heat transfer coefficients on the surfaces of a ground mounted stand-alone solar panel under varying wind speeds and directions.
1.4 Organization of the thesis
This thesis is written in the “integrated article” format as specified by the Faculty of Graduate Studies at Western University.
This thesis is organized into 6 chapters. Chapter 1 provides a general introduction presenting an in-depth literature review related to wind loading and heat transfer for solar panels. This chapter also depicts the motivations and objectives for the present study. Chapter 2 is based on a technical paper published in the Journal of Wind Engineering and Industrial Aerodynamics on wind effects on ground mounted stand-alone solar panel using CFD. In Chapter 3, the wind flow structure around a stand-alone ground mounted PV system is analyzed using PIV and HWA in the boundary layer wind tunnel. This chapter is a technical article prepared for the Journal of Fluids and Structures. Analysis of aerodynamic forces on an array of ground mounted solar panels under varying wind direction is illustrated in Chapter 4. Chapter 4 is also based on a technical paper prepared for the Journal of Wind Engineering and Industrial Aerodynamics. Chapter 5 presents the effect of wind speed and direction on the convection heat transfer from the surfaces of a stand-alone ground mounted PV system using CFD simulations. Chapter 5 is again a technical paper which will be submitted to the Journal of Solar Energy. Finally, the thesis
ends with conclusions as well as the contributions of this work and recommendations for future studies.
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