查看更多>>摘要：An attempt has been made to develop a thermal model of a semi-transparent photovoltaic thermal (SPVT) air collector connected in series and parallel for a given total number of PVT air collectors. It has been observed that the temperature of outlet fluid (air) increases with the increase of the number of SPVT air collectors connected in series along with the decrease in electrical efficiency of a solar cell of PV module. In order to maximise the thermal as well as electrical output, one has to analyse the combination of SPVT air collectors (N). It has been observed that: 1) all SPVT air collectors should be connected in series based on an overall thermal energy; 2) 3-SPVT and 4-SPVT air collectors should be connected in series and parallel combination respectively for maximum overall exergy for given 12-SPVT air collectors. Further, the effect of mass flow rate and packing factor has also been studied.
Pushparaj R. JiwanapurkarHitesh A. BhargavBharat Ramani
241-258页
查看更多>>摘要：Spectral beam splitting (SBS) is a photovoltaic thermal technology that offers conversion of the complete solar spectrum incident on earth surface into useful energy with maximum efficiency. The efficiency of photovoltaic-thermal system can be increased by separating the responsive range of PV cell from the solar spectrum by SBS technique and utilising both wavelengths range separately for photovoltaic and thermal conversion. A review of development of a fluid-based SBS filter with help of organic fluids, and nanofluids in the last decade have been reported in this article. Varieties of pure fluids and nanofluids tested as SBS filters have been discussed. Organic fluids like water, coconut oil and silicon oil were identified as potential fluids for filtering of solar spectrum, 79% thermal and 14% electrical efficiency was estimated mathematically. Highest overall efficiencies of PVT system using fluid-based SBS filter was found out to be 56% and 62% with C-Si and GaAs solar cells respectively using gold (Au) nanofluid. The cost of nanofluids needs to be justified with an increase in the system's overall efficiency. An ideal SBS filter transmitting only the responsive wavelength range of the PV cell has to be developed for commercialisation of SBS PVT system.
查看更多>>摘要：Energy demand is increasing rapidly, and as per forecast, this time's important fossil energy source will end in the next 50 years. Everyone has to think of some renewable energy source to meet future energy demand. In this study, the experimental analysis of biofuel production from used cooking oil and its performance and emission analysis is done for fuel blending B00, B05, B10, and B15. The biodiesel yield obtained is 97% with 1:10 oil methanol ratio with transesterification reaction. The biofuel's viscosity is 2.061 cp and viscosity of used cooking oil was 25.78 cp. Engine behaviour have been analysed for all fuel blending. The fuel blending B10 has shown the better engine performance among all other fuel. In the emission analysis, the fuel blending B10 shows the maximum CO_(2)and NO_(X)emissions. HC emission is maximum for B15 and minimum for B05 fuel blending. Minimum CO emission was found for fuel B10.
查看更多>>摘要：The airfoil thickness is investigated on its effects in efficiency and structural characteristics in a wind turbine blade. Eight single-airfoil blades are constructed based on a fixed-speed fixed-pitch design and their corresponding optimum design to accurately describe the airfoil thickness effects on the overall geometry of the blade. Based on a linear profile, the geometry of the blade is optimised with the use of the blade element momentum theory. By also obtaining the performance of the blade, this study reveals the airfoil aerodynamic characteristics in which a thinner airfoil reaches a glide ratio that is greater than its thicker counter parts, however, an unstable stall is also encountered with a thinner airfoil ultimately reducing the blade's overall efficiency. A nonlinear static simulation is conducted on the blades based on extreme wind conditions revealing an increase in deflection and stress on the blades as the airfoil thickness decreases.
查看更多>>摘要：In India, due to the abundant source of solar energy, it is considered the essential energy source. There are many solar energy technologies available for various purposes like drying, cooking, heating, water production, generation of electricity, etc. Solar drying is a potential application to conserve crops in the tropical region of India. The modern technology of drying needs to be upgraded because of the intermittent supply of solar energy during the night and in cloudy seasons. Thermal storage is incorporated to improve the work of equipment. As already reviewed by many researchers, sensible and latent heat storage materials are used to enhance the quality of work of thermal storage. The current review article shows solar drying technologies for the purpose of drying products. Different technologies incorporated into solar drying like thermal storage (sensible and latent), nanomaterial applications, and many more are included in this article. The current article also depicts different technologies that are not currently used in solar drying technologies, but in the future they may be. From this review article, it is clear that solar drying is a very important way to speed up the drying process.
NETL
NSTL