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In this work, the examination of an experimental air-cooled photovoltaic-thermal (PV/T) module is introduced. Two different shapes of fin fixed to the copper absorber plate are examined for the classical unit of an air-cooled PV/T collector. Vertical and louver-shaped fins (with the same surface area) are investigated and thermally evaluated in this study. The experiments aimed to increase the temperature difference between inlet and outlet air to reach high thermal performance. The enhancement result showed that the thermal efficiency of the louver fin unit increased by 48% and 54% compared to the vertical fin and unfinned units, respectively. Thus, louver fins are better than vertical fins with the same surface area [ABSTRACT FROM AUTHOR]

Researchers, engineers, scientists, and other professionals have been focusing on the exploitation of nanotechnology with specific attention to nanofluids and their property of dynamic viscosity that can do wonders in the field of engineering. This study was aimed at determining the dynamic viscosity of the given hybrid nanofluid (distilled water based ZrO 2 /SiC) by studying the nanofluid's rheology. In this regard, a two-step method was employed for the dispersal of nanoparticles in the base fluid. The nano-powder was composed of ZrO 2 and SiC in a ratio of 1:1 (50% - 50%). The dynamic viscosity of solid volume fractions 0.025% - 0.1% was measured in temperatures 20–60 °C by using DV2TRVTBG Brookfield digital viscometer. The research indicated the association between the nanofluid's viscosity and the factors of temperature and solid volume fraction. At first, in order to assessment the characteristics and stability of nanoparticles into the base fluid, XRD, TEM, FESEM, EDX, UV–vis spectrometer, DLS, and zeta potential test were used on ZrO 2 and SiC nanoparticles. The results indicated an increase in dynamic viscosity at higher solid concentrations and falling temperatures. The dynamic viscosity increase of the nanofluid was recorded at 20 and 60 °C, which showed a 29.6% and 64.2% rise in the viscosity respectively in the presence of 0.025% of nanoparticles in the nanofluid. This implies that the viscosity of nanoparticles becomes more sensitive at high temperatures. The experiment showed a maximum viscosity rise of 169.4%. The experiments also discovered that ZrO 2 -SiC /DW hybrid nanofluid can be successfully used in different devices as a Newtonian fluid since it depicts Newtonian properties at various temperatures. In addition, the study put forward a new correlation for determining the dynamic viscosity of hybrid nanofluid using the experimental data (temperature and solid volume fraction). The value of mathematical correlation accuracy was 98.92%. During the experiment, the sensitivity of viscosity in response to a rise in solid volume fraction was evaluated. Lastly, an acceptable level of accuracy of the correlation outputs was seen when the theoretical and practical values were contrasted. [Display omitted] • Experimental study on dynamic viscosity of ZrO 2 -SiC/DW hybrid nanofluid. • The Newtonian behaviour of nanofluid was observed at each temperature setting. • An increase in the solid volume fraction causes the viscosity to rise. • The study put forward a new correlation for predicting the nanofluids viscosity. • The sensitivity analysis of the viscosity of hybrid nanofluid is also performed. [ABSTRACT FROM AUTHOR]

In this article, an experimental estimation of thermal efficiency of horizontal and vertical-finned double-pass solar air collectors integrated with drying chamber has been carried out. The rig consists of two main parts as solar collector and dryer. The system was installed in the laboratory of Szent István University, Gödöllő, Hungary. The absorbers were made from a copper integrated fins in horizontal and vertical directions. The test results showed that the daily efficiency increased by10% when the direction of fins have been changed from vertical to horizontal. After 5 h drying of 2 kg apple slices, the final weights were 1.16 and 1.37 kg by using horizontal and vertical-finned collectors, respectively. [ABSTRACT FROM AUTHOR]

Studying heat transfer problems of supercritical water the pressure dependency of thermophysical parameters (density, specific heat, viscosity, and thermal conductivity) and the work done by pressure are often neglected. Here we show that the variations of some physical parameters as functions of pressure have the same order of magnitude than their variations as functions of temperature in supercritical water Therefore, pressure dependency of physical parameters should be taken into account in heat transfer calculations of supercritical water It is also pointed out that the work done by pressure should not be neglected in supercritical water since the pressure work term has the same order of magnitude than the convective term near the pseudo critical temperature. [ABSTRACT FROM AUTHOR]

Scientists initiated a pursuit of more resilient and long-lasting energy sources due to the continuous deterioration of the environment and the substantial rise in the expense of conventional energy sources. Solar energy is one of the most cost-effective, environmentally friendly, and easily accessible sustainable energy sources. Photovoltaic/thermal (PV/T) solar modules are gaining popularity due to their ability to utilise more solar radiation to generate electric power and heat gain simultaneously. This study reviews recent advancements in PV/T modules, focusing on the dual conversion of solar radiation into electrical and thermal energy. The review highlights significant improvements, such as the use of nanoparticles, bi-fluid circulation, and innovative cooling techniques. The study examined the main categories of PV/T systems, including air-cooled, water-cooled, bi-fluid-cooled, nano-fluid-cooled, and ternary nanofluid-based units. This paper offers an in-depth analysis of various components within PV/T modules, covering aspects such as concepts, materials, and review techniques. However, challenges remain, including the trade-off between thermal and electrical efficiency and integration into existing infrastructure. Despite these limitations, PV/T systems show great potential for contributing to sustainable energy solutions and achieving global sustainable development goals. Future research directions include integrating an artificially intelligent approach for system optimization and expanding hybrid PV/T technologies. [Display omitted] • A graphical summary of the PV/T types is demonstrated. • Sustainability achievements by the PV/T modules are discussed. • Water, air, nanofluid, and bi-fluid-based coolants are summarised. • Ternary nanofluid-based PV/T is reviewed. [ABSTRACT FROM AUTHOR]

An introduction to the periodical is presented including articles published related to papers of the European Drying Conference held in October 21–23, 2015; and role of Ian Kemp and Antonio Mulet as reviewers; and role of Arun S. Mujumdar as editor of the periodical.

The first part of this paper assesses the state of solar PV in Hungary, considering available government support in terms of policies, targets, and the conducive environment for exploiting solar PV. The study further analyses a 15-year-old 9.6 kWp roof-mount grid-connected solar PV system whiles comparing its performance parameters with similar installations in the sub-region. Findings show that Hungary possesses a relatively high solar energy resource which has not been exploited as expected compared to most of the countries in the European sub-region. Hungary has in place the necessary policies and diverse incentives for the adaptation of renewable energy sources as required by the European Union. However, complexities in land acquisition and legal definitions of PV systems still exist. The installed solar PV capacity in Hungary as of 2018, is 790 MWp. The target of the Hungarian Renewable Action Plan is to have 14.65% of the electricity demand supplied by renewable energy sources by 2020. The experimental study shows that the total energy output from the 9.6 kWp system is 8838.95 kWh for the year of assessment. The energy outputs for the subsystems are 3761.98 kWh, 2608.88 kWh and 2468.10 kWh for ASE (pc-Si), DS2 (a-Si) and DS1 (a-Si) respectively. The annual sub-system efficiencies are 9.8%, 2.9% and 2.8% for ASE (pc-Si), DS2 (a-Si) and DS1 (a-Si) respectively. Thus, 42.6% of energy fed into the grid was from the ASE (pc-Si) system, 29.5% and 27.9% from the DS2 (a-Si), and DS1 (a-Si) respectively. • The state of solar PV in Hungary and the related policies for adaptation reviewed. • Long term assessment of different grid-connected solar PV systems studied. • Performance ratios of studied PV systems range between 55.6 and 77.2%. • System efficiencies vary from 2.8% to 11.5%. [ABSTRACT FROM AUTHOR]

Reliability assessment of Photovoltaic (PV) modules is very crucial to increase the service lifetime of PV systems. This study assesses the degradation rate and reliability of PV modules operated for twelve years under the tropical climatic condition in sub-Saharan. For this purpose, various characterization techniques, namely visual inspection, infrared (IR) thermography assessment, and current-voltage (I-V) characterization, have been employed to evaluate the performance of PV modules. Moreover, the functioning of bypass diodes has been tested under partial shading situations. The results demonstrate that after twelve years of outdoor operation, the short-circuit current (I sc) of modules have been degraded up to 16.4% with an average decrease of 11.7% compared to the nameplate values. The open-circuit voltages (V oc) were reduced from 11.4% to 17.1% with a mean of 14.8%. The decline in Fill Factor (FF) of the modules ranges from 11.3% to 24.2%, and the losses of power output were between 34.5% and 41.4%. Moreover, the visual and thermography assessment reveals that the PV modules are severely affected by various failures such as EVA browning, cell interconnects ribbons browning and the corrosion of solder bonds. The results show that averagely, the FF is the most significant factor influencing the loss in the power output of the modules. • Degradation of PV modules under hot, humid tropical climate for 12 years assessed. • PV module characteristics normalized at STC using derived translation equations. • Influence of module parameters on degradation evaluated using regression analysis. • The average degradation of nominal power is 3.19%/year. • The combination of Isc-Voc had the most impact on the variation of nominal power. [ABSTRACT FROM AUTHOR]

Abstract: For corn drying one of the most popular possibilities in Europe is to use a mixed flow dryer. Large differences in the vertical grain particle velocity in this type of dryers are causing differences in the residence time. Hence, uneven drying occurs causing under-drying or over-drying of grain portions. To investigate the influences of the dryer walls and the air ducts on the particle velocity distribution experiments have been carried out in industrial and laboratory sized dryers and the measurements were compared with discrete element models. The particle flow velocity distribution between the air ducts is modelled analytically based on arching hypothesis. Using discrete element models the effects of different possible constructional modifications causing more even vertical grain particle velocity distribution were analyzed. [Copyright &y& Elsevier]