This article investigates and presents the upshots observed in the brook of hybrid composites especially, the current investigation focuses on the impact of fiber composition, sequence, and stacking pattern on composite mechanical Features. Five varied stacking sequences of hybrid composites encompassing laminates are used to create four classes of fiber with jute/bamboo/glass by utilizing a conscientious hand lay‐up process with glass fiber‐laced mats as their peripheral layer. For examination, fiber sequences are arranged in the combination of GJBJG, GBJBG, GJGJG, and GBGBG, where G, J, and B refer to glass fiber, jute fiber, and bamboo fiber, respectively. The position of fiber in the core layer is kept in a perpendicular direction with respect to adjacent piles which might be jute or bamboo fiber and the best position of fiber is considered due to the stacking order. Stress and strain were linear in the load versus deflection curves, and all of the samples failed quickly, it is observed that the sample containing a higher or considerable number of bamboo fiber layers exhibited increased strain and toughness. In comparison to other samples, embolism of glass fiber as the main and covering layer expressed a higher impact on the mechanical properties of the composites is observed in this investigation. The shattered sample morphology demonstrated that the matrix and reinforcements were compatible.
In the automobile sector, pistons are anodized on the crown, on ring grooves, and also on skirts to improve its wear resistance and corrosion resistance properties. In this work, we have carried out crown anodizing along with skirt anodizing simultaneously to study the wear resistance of anodized samples. The surfaces are anodized with three different processes such as soft anodizing, hard anodizing, and microarc oxidation (MAO) or well known as plasma arc oxidation (PAO). All the three processes differ in their respective procedures. The hardness value and microstructure of all the samples were tested to find wear resistance values and the effect of coatings on the samples. In wear testing, piston samples are rubbed on cast iron to denote its wear resistance based on weight loss per unit time. Reciprocating wear testing is also carried out on every sample for testing their wear resistance value.
The present research work aimed to investigate the melting and solidification characteristics of NPCM. The NPCM was prepared using paraffin as the PCM and high conductive MWCNT as the nanomaterial without using any dispersant. The NPCM was prepared by dispersing MWCNTs with volume fractions of 0.3%, 0.6% and 0.9% in PCM as the base PCM. SEM morphology showed the uniform dispersion of MWCNTs in the paraffin wax. The MWCNT nano-additives PCMs showed two peaks in the heating curve by DSC measurement. Lessening in melting and solidification time of 30% and 43% was attained in the case of NPCM with 0.3% and 0.9%, respectively. It is observed from the DSC analysis that the latent heat of pure paraffin during freezing and melting cycle was 139.2 J/g (at 56.61 °C) and 131.8 J/g (at 57.55 °C), respectively. Whereas, the latent heat of NPCM with 0.9% of nanofluid was 150.7 J/g (at 56.36 °C) and 148.3 J/g (58.35 °C). It is construed that a maximum change in latent heat of 7.6% and 11% was observed between pure PCM and NPCM during freezing and melting cycle. For the lesser nanoparticle concentration (0.3% and 0.6%), the percentage change in latent heat was lesser than 0.9%.
Nickel‐based super composites are widely applied in the industry. These alloys withstand high thermal debility conditions and give better strength to machine parts in aviation, biomechanical, marine, and vehicle commerce. Nickel‐based alloys have high quality, corrosion resistance, and high heat refusal. Inconel 718 is one such composite extensively utilized in these loading circumstances because of chemical stability, mechanical friction, high thermal corrosion, and high stability. During the cutting procedure, these qualities will bring a lot of processing issues, for example, surface roughness, machining efficiency, and wear of tool. Plasma arc cutting (PAC) is an upsetting metal‐cutting process to perform slicing of hard to cut materials even for complex profiles. The present work analyzes the impact of PAC process factors, for instance, gas pressure (GP), arc current (AC), cutting speed (CS), and stand-off distance (SOD) on assessing the kerf width (KW), kerf taper (KT), and heat-affected zone (HAZ) of Inconel 718 superalloy. This work deliberates about the cutting parameters required for the machining of Inconel 718 to provide least surface roughness and low instrument wear. The experiments conducted to validate the ingenuity of the process are in accordance with the optimal parameter settings necessary for machining purposes. The divergence from actuality has been extremely minimal with a relative error of 4.45% for kerf width and 4.36% for the extent of heat-affected zone postmachining.
The main aim of this present work is to explore the influence of dispersion of MWCNTs in a mixture of water-solar glycol (70:30) on its electrical conductivity and thermophysical properties such as density, rheology and thermal conductivity. The MWCNTs were seeded with a various weight percentage of 0.15, 0.3 and 0.45 via a common two-stage synthesis technique. The homogeneous stability of MWCNTs based nanofluids was confirmed by high-resolution scanning electron microscopy and ultraviolet-visible spectroscopy. The density of solar glycol and H2O mixture based MWCNTs nanofluids were measured with standard borosil volumetric flask via weighing balance mechanism and the experimental findings displayed a good agreement with the well-known correlation of Pak and Cho owing to the natural packing of H2O inside the nanomaterial in a limited quantity. The thermal conductivity of 0.45 wt. % MWCNTs seeding got augmented by 19.12% at ambient temperature while the electrical conductivity got augmented by 93.54% at 50 °C. Therefore, the augmentation in the thermal conductivity of water/solar glycol mixture with 0.45 wt. % MWCNTs seeding is because of the kinetics of nanomaterial accumulation and fluid layering. In addition, mathematical correlations were recommended for estimating the ratio of the thermal conductivity and viscosity of the nanofluid at different weight fractions.
29 May 2018 in International Journal of Ambient Energy
This paper analyses and compares the effects on outlet water temperature, heat transfer rate and its thermal efficiency of three different types of tubes such as twisted tape inserted tube, louvered strip inserted tube and a surface treated (laser peened) tube are dealt with different operating parameters, viz., solar insolation, water temperature at the inlet and ambient temperature. Non-concentrate collector (flat plate) is used. A plain or normal tube (non-surface treated) was also tested for comparison. Polystyrene and acrylic glasses were used for reduced heat loss. It is observed that the heat transfer rate and its thermal efficiency tend to increase with the increased ambient temperature and solar insolation with the louvered strip inserts had given the best thermal performance in comparison with the other types.