| Energy is one of the essential factors for human survival.In the last few decades,energy consumption in many fields is increasing,and human dependence on energy is increasing.At present,in the energy structure,fossil fuel is the main way for human beings to obtain energy.However,a large number of wastes generated by the abuse of fossil fuel has caused many irreversible damages to the environment,resulting in many environmental problems,such as geological disasters,extreme weather phenomena,glacier melting.Therefore,solar energy is ultillized widely in many fields,especially in photovoltaic power generation.In this thesis,the temperature distribution of photovoltaic solar panels with phase change materials is studied by simulation at different tilt angles and different protecting thicknesses.The transient method is used to analyze the heat transfer process of photovoltaic solar panels during cooling process.At the same time,the melting process of PCM was studied by capturing the profile of liquid components.Three-dimensional geometry was prepared to model the PV panel with the same length and width(500 mm×500 mm).For the current study,the height of the fluid domain is 0.1 m.The 3D model represents the volume of the cooling fluid(Fluid Domain).The external wall(500 mm×500 mm)was used to model the PV external surface which had the properties of the PV cell layer.That was assumed for simplicity.Air was used as the cooling fluid for the model verification.A phase change material and water are also used for the other simulations.The inlet velocity of the air was 0.5 m/s with turbulence intensity 0.055%and the hydraulic diameter was 0.166 m at 308 K.The solar ray tracing method was used to investigate the thickness change of the aluminum cover.It was discovered that increasing the thickness to 9 mm enhanced the cooling effect but it was close to the small thickness’s cases.However,increasing the thickness to 15 mm helped in protecting the unit from the outside heat but it let the inside heat of the unit to be stored leading to an increase in the temperature.It was found from the transient simulations that were carried out using the PCM at different solar flux values that increasing the flux increases the temperature and hence decreases the heat dissipation efficiency.However,using liquid water at the same conditions did not enhance the efficiency but affected it badly.For example,the efficiency increased by 0.08%when the PCM was used rather than water at the same boundary conditions and solar flux 1000 W/m~2.For example,at 1000 W/m~2 and the same boundary conditions,the efficiency of the PV was 14.31%at water mass flow rate 0.2 kg/s,while it was 13.53%in the case of stored water,while it was 13.61%in the case of using the PCM as a stored material.Increasing the mass flow of water can improve the performance of photovoltaic,but it increases the complexity and the initial costs.At the same time,this paper discusses the improved solar panel structure to adjust the performance of solar panels.By comparing the two structures of 1 and 2 fins with the previous structure,the best structure is obtained. |
