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Planar glass cover creates optical reflection loss and glare, which is harmful to energy efficiency and effective operation of PV modules, especially at larger angles of incidence (AOIs). Textured surfaces can reduce reflections and glare intensity. In this work, three textured glass surfaces are described and simulated numerically over a wide range of AOIs. The anti-reflection effect and light trapping effect are provided to analyze the transmission gain across a wide range of AOIs. The reflection times is proposed to assess the anti-glare effect of the textured surfaces. It is found that the hexagonal array structured surface exhibits the highest transmission gain and anti-glare effect. The optimized hexagonal array structured surface could improve the average transmission by ∼5% relative to planar surface for AOIs of 0°–80°. In addition, the reflection times is doubled, which helps to diminish the reflection and glare intensity. [ABSTRACT FROM AUTHOR]

Building integrated photovoltaic modules, applied to industrial and commercial buildings, generally used metal as the backsheet. In summer, the operating temperature of modules is as high as 70°C, resulting in instability of output power and service life. Therefore, it is very important to reduce the operating temperature of photovoltaic modules. In this work, Al2O3/graphene/poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) composite radiative cooling coatings were prepared and utilized for reinforcing heat dissipation of photovoltaic modules. The results indicate that 0.75 wt%Al2O3/1wt%graphene/PVDF‐HFP composite coating exhibited a thermal diffusivity of 3.24 μm2/s and an average emissivity of 0.94. The maximum temperature drop of the coating in the outer door reached 5.8°C. In addition, a mini photovoltaic module coated with the composite coating achieved the cooling effect of 2.4°C, and the output power and conversion efficiency were increased by 5.8% and 7%, respectively. This demonstrates that the heat conduction radiative cooling coating possesses potential applications for improving the reliability of photovoltaic modules. [ABSTRACT FROM AUTHOR]

TC4 particles reinforced AZ31 composite was successfully prepared by innovatively using simultaneous feeding method of powder and wire in wire-arc directed energy deposition (WA-DED). The results indicated that TC4 particles are expected to be evenly distributed in the AZ31 matrix and the introduced TC4 particle content of 9%−33.43 wt% can be acquired by adjusting the turret speed (TS) of powder feeder. The coarse columnar grains in the AZ31 transforms into the equiaxed grains after adding TC4 particles. A large number of acicular/flake Mg-Al phase and partial granular Al-Mn phase are formed around TC4 particles. The excellent tensile properties with yield strength of 85.6 MPa, ultimate tensile strength of 195 MPa and tensile elongation of 7.1% are obtained at the TS of 5 rpm, the corresponding maximum improvement efficiency reaches up to 42.6%. The improved strength mainly derives from grain refinement strengthening and thermal mismatch strengthening. [ABSTRACT FROM AUTHOR]

In this paper, two analytic methods are presented to predict the geometry of resin pockets formed around rigid fiber inclusions at the interlayer of unidirectional prepregs. The bending strain energy is calculated on fiber scale in one method, while it is calculated on layer scale in the other method. For the fiber scale method, several fibers in thickness direction are tied together to account for the bending stiffness increase caused by the interaction between fibers. And for the layer scale method, a single ply is divided into several sublayers to account for the bending stiffness decrease caused by the sliding between adjacent fibers. Both analytic methods can provide the closed-form solution for the resin pocket width, and the analytic results agree well with experimental results. The physical consistency of two methods is proved. It is found that the resin pocket size depends mainly on ply angles of the plies close to the inclusion, and the stacking sequence has some effect. [ABSTRACT FROM AUTHOR]

In this work, gram‐scale branched‐VO2 (B‐VO2) was synthesized via a mild one‐step hydrothermal route, and the corresponding phase transition, optical and electrical performances of B‐VO2 were investigated. The differential scanning calorimeter (DSC) results revealed the defect mediated phase transition behavior of B‐VO2. The optical studies demonstrated an analogous negative thermochromic performance of B‐VO2, which was ascribed to the intense Mie scattering effect. While, ball milling treatment was an effective way to restore the regular thermochromic property, and the ball‐milled VO2 (BM‐VO2) displayed a 6.3 % increasement of the solar modulation ability. The BM‐VO2 films on flexible PET and PI substrates demonstrated both energy‐saving and UV‐shielding functions. The temperature dependent resistivity displayed about two orders of magnitude change during the phase transition of VO2. [ABSTRACT FROM AUTHOR]

Experimental and numerical study are carried out to investigate hygrothermal effects on the mechanical behavior and damage propagation of scarf repaired carbon fiber reinforced plastic (CFRP) laminates. Experimental tests were carried out under four environment conditions: room temperature/dry, room temperature/wet, elevated temperature (95°C)/dry and elevated temperature (95°C)/wet. Results showed no decrease in compression strength after moisture absorption, whereas the reduction under elevated temperature were 15.5% and 17.2% for dry and wet specimens, respectively. Furthermore, a finite element model was developed to simulate the failure process and predict structural strength, in which moisture diffusion, hygrothermal stress analysis and progressive damage model were considered. Good agreement was achieved between the predicted compression strength and experimental results. It is revealed that the damage in the adhesive initiates adjacent to 0° plies and propagates in circumferential direction. Water absorption causes initial damage in the edge of the adhesive layer, while it does not reduce the compression strength. And elevated temperature leads to earlier damage in adhesive. After large part of the adhesive layer damaged, damages in parent laminate occur and propagate transversely to the free edge sides until the final structural collapse, which is similar with the experimental phenomenon. POLYM. COMPOS., 39:904–914, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]