The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Guiyin Fang - One of the best experts on this subject based on the ideXlab platform.
-
maximizing the energy output of a photovoltaic thermal solar collector incorporating phase change Materials
Energy and Buildings, 2017Co-Authors: Di Su, Guiyin FangAbstract:Abstract Photovoltaic–thermal collector can simultaneously generate both electricity and heat, making full use of the solar energy. It is worth to increase the electrical output by reducing the operating temperature. An effective method of cooling the cell temperature is incorporating phase change Materials into the collector. In order to maximize the energy output and improve the performance of the collector, we perform comparative analyses on a hybrid photovoltaic–thermal solar collector incorporating phase change Materials with different melting point. Solar cell temperature, electrical power, electrical efficiency, outlet temperature of water, thermal power output of the collector by varying melting point and thickness of phase change Material Layer are evaluated using one dimensional energy balance method. The corresponding graphical representations are described to explain the way of maximizing the electrical and thermal energy output of this system. And the numerical results have provided guidance for further experiment. In this theoretical work, it is found that phase change Material Layer with lower melting point has better electrical properties of the collector, while the heat stored in phase change Material Layer is more difficult to utilize. The results show that the photovoltaic–thermal solar collector gets a maximum of overall energy output by incorporating 3.4cm-thick phase change Material Layer with 40 °C melting point. By contrast of the electrical power of 30 °C melting point case and no phase change Material case, the biggest value of difference is 16.12 W at 12:00. It means that the electrical power of the collector has increased around 13.6% by incorporating phase change Material Layer with 30 °C melting point.
Agis M Papadopoulos - One of the best experts on this subject based on the ideXlab platform.
-
phase change Material based cooling of photovoltaic panel a simplified numerical model for the optimization of the phase change Material Layer and general economic evaluation
Journal of Cleaner Production, 2018Co-Authors: Muslum Arici, Feyza Bilgin, Sandro Nižetic, Agis M PapadopoulosAbstract:Abstract This paper deals with the application of PCM as the assumed coolant in the case of photovoltaic applications. A simplified numerical model was developed to be able to analyze the expected efficiency improvement of a PV-PCM system as well as the expected reduction of the PV panel's operating temperature. The developed model was validated with the available experimental data from existing literature with maximal deviation ranging from 1% to 3.1%. Different PCMs with different melting temperatures and latent heat fusion were examined to identify the suitable PCM for the PV panel for the given climatic conditions. It was found that the application of a PCM Material is reasonable from a technical point of view, as it reduces the PV panel operating temperature by up to 10.26 °C and thus increases the efficiency by up to 3.73%. The economic aspect application of the PCM Material for the PV-PCM based cooling was also addressed. It was found that a significant decrease in the initial price of the PCM Material is necessary to ensure a more feasible LCOE. The herein obtained analysis showed therefore, that a PCM Material could be a promising option for PV-PCM applications provided a significant drop in PCM's costs coupled with an efficient thermal management of the PV-PCM system.
Di Su - One of the best experts on this subject based on the ideXlab platform.
-
maximizing the energy output of a photovoltaic thermal solar collector incorporating phase change Materials
Energy and Buildings, 2017Co-Authors: Di Su, Guiyin FangAbstract:Abstract Photovoltaic–thermal collector can simultaneously generate both electricity and heat, making full use of the solar energy. It is worth to increase the electrical output by reducing the operating temperature. An effective method of cooling the cell temperature is incorporating phase change Materials into the collector. In order to maximize the energy output and improve the performance of the collector, we perform comparative analyses on a hybrid photovoltaic–thermal solar collector incorporating phase change Materials with different melting point. Solar cell temperature, electrical power, electrical efficiency, outlet temperature of water, thermal power output of the collector by varying melting point and thickness of phase change Material Layer are evaluated using one dimensional energy balance method. The corresponding graphical representations are described to explain the way of maximizing the electrical and thermal energy output of this system. And the numerical results have provided guidance for further experiment. In this theoretical work, it is found that phase change Material Layer with lower melting point has better electrical properties of the collector, while the heat stored in phase change Material Layer is more difficult to utilize. The results show that the photovoltaic–thermal solar collector gets a maximum of overall energy output by incorporating 3.4cm-thick phase change Material Layer with 40 °C melting point. By contrast of the electrical power of 30 °C melting point case and no phase change Material case, the biggest value of difference is 16.12 W at 12:00. It means that the electrical power of the collector has increased around 13.6% by incorporating phase change Material Layer with 30 °C melting point.
Benedetta Copertaro - One of the best experts on this subject based on the ideXlab platform.
-
A refrigerated container envelope with a PCM (Phase Change Material) Layer: Experimental and theoretical investigation in a representative town in Central Italy
Energy Conversion and Management, 2016Co-Authors: Roberto Fioretti, Paolo Principi, Benedetta CopertaroAbstract:In this paper, a novel technology to improve the thermal performance of reefer container envelopes using a Phase Change Material (PCM) has been investigated. To that end, an external PCM Layer was integrated with an insulated sandwich panel, in order to reduce and displace the heat flux phase caused by the external climatic conditions. The proposed technology was evaluated using an experimental and numerical design study. Specifically, during the experimental activities, a prototype panel was first tested inside a climatic test room and subsequently assembled on mini cold rooms and evaluated under real summer environmental conditions in Ancona (Italy). Finally, the numerical analysis was carried out using Finite Element Method (FEM) software in order to simulate a two-dimensional unsteady-state heat transfer with PCM. The calculation results were compared with the experimental values in order to validate the mathematical model, achieving a high reliability (correlation coefficient equal to 0.95).
Sai Zhang - One of the best experts on this subject based on the ideXlab platform.
-
dynamic stress from a cylindrical inclusion buried in a functionally graded piezoelectric Material Layer under electro elastic waves
Composites Science and Technology, 2009Co-Authors: Xueqian Fang, Ting Zhang, Xiaohua Wang, Sai ZhangAbstract:This paper presents a theoretical method to investigate the multiple scattering of electro-elastic waves and dynamic stress around a subsurface cylindrical inclusion in a functionally graded piezoelectric Material Layer bonded to homogeneous piezoelectric Materials. The analytical solutions of wave fields are expressed by employing wave function expansion method, and the expanded mode coefficients are determined by satisfying the boundary conditions around the inclusion. The image method is used to satisfy the mechanical and electrically short conditions at the free surface of the structure. Through the numerical solutions of dynamic stress concentration factors around the inclusion, it is found that when the cylindrical inclusion possesses higher rigidity and greater piezoelectric constant than the two phases of functionally graded Materials, the dynamic stress around the inclusion increases greatly. When the distance between the surface of the structure and the inclusion is smaller, the effect of the properties of the inclusion becomes greater. When the cylindrical inclusion possesses lower rigidity and smaller piezoelectric constant than the two phases of functionally graded Materials, the maximum dynamic stress shows little difference; however, the variation of the distribution of the dynamic stress around the inclusion is greater. The effect of the properties of the inclusion on the dynamic stress around the inclusion is greater than that on the electric field. The effects of wave frequency on the dynamic stress and electric field are also examined.