Applied Mechanics and Materials Vol. 612

Abstract: In the present work a new natural fibre i.e. sacred grass botanically called Imperata Cylindrica is introduced and it belongs to vedic grass family. The fibre is extracted by splitting method and is reinforced into the polyester matrix by hand lay-up technique for the fabrication of tensile, flexural, impact, dielectric test specimens as per ASTM procedures. Highest values of tensile strength (50.96 MPa), modulus (990.86 MPa) are observed for sacred grass fibre reinforced polyester composites at maximum volume fraction of chemically treated fibre. At 14.75 %, 35.89 % sacred grass fibre volume fraction the composites exhibited flexural strength, modulus of 43.19 MPa, 4.81 GPa respectively. Impact strength of 92.53 kJ/m² is obtained for the composites reinforced with 34.73 % volume fraction of sacred grass fibres. The dielectric strength of the composites varies from 10 to 6.66 kV/mm for composites reinforced with fibres from minimum (6.26 %) to maximum (32.25 %) fibre content.

Abstract: Helmet protection to vulnerable two wheeler riders presents many challenges including those of weight, ergonomics appearance and convenience. Safety provided to a two wheeler riders head is mainly dependent on the level of shock getting propagated to the brain during the accident situations and therefore the design of the layer of shock absorbing padding assumes great importance. This padding, generally made of expanded polystyrene (EPS) or of state of art materials needs to be optimized. Helmets prototypes using an external hard shell made of Fiber Reinforced Plastic (FRP) were built to the different thicknesses and impact absorption tests on different types of test rigs were conducted

Abstract: Wind energy and solar energy are prominent renewable energy options in the view of growing energy demand. Reliable small wind power produced at compatible price is the need of hour. Cost of the energy generation depends on the cost of the materials used, operating and maintenance cost, cost of the fuel. The material cost directly relates to the cost of the energy. Blade design plays significant role in any wind turbine design. In order to have long expected life of blade material selection is a crucial stage in blade design. Wood, Glass fiber, carbon fiber, natural fiber, sandwich composite materials are different material available for small wind turbine blades. Strength, durability, density, cost, and availability are the important properties to be considered during material selection of blade. The selection of material for wind turbine blade is an important stage in blade design. This paper presents a simple Analytic Hierarchy Process for material selection for the small wind turbine blade. AHP is one of the simplest and cost effective decision making method. In this work AHP is successfully applied for material selection for small wind turbine blade.

Abstract: Aluminium matrix composites (AMCs) play a vital role as advanced engineering materials due to their excellent mechanical properties like light weight, strength, wear resistance, toughness. This work focuses on the fabrication of aluminium (AA6061) matrix composites reinforced with 3%, 6% and 9% B₄C particle of 104μm using stir casting method. The wettability of B₄C particles in the matrix has been improved by adding K₂TiF₆ flux in to the molten metal. The microstructure and mechanical properties of the fabricated AMCs are analyzed. Uniform distribution of B₄C particle in the matrix was confirmed using scanning electron microscope (SEM) images. It was found that the tensile strength and hardness of the fabricated AMCs increases with increased B₄C particle content.

Abstract: Wear behaviour of aluminium matrix composites are characterized by pin on disc wear test using various parameters such as sliding distance, sliding speed and load. MMC consists of aluminium alloy (A356) as the matrix material and particulate alumina of 5% and 10% by weight as the reinforcement was fabricated using stir casting. Wear resistance of composites are improved by the presence of reinforcements. Experiments were conducted based on the plan of experiments generated through Taguchi Technique. L₉ orthogonal array was selected for analysis of data. The objective of this investigation is to study the influence of sliding speed, sliding distance, load and weight percentage reinforcement on wear rate of fabricated metal matrix composites.

Abstract: Fabrication of PAMC by stir casting, at semisolid stage of the matrix results in homogeneous distribution of the reinforcements in the matrix, which leads to better mechanical and tribological property of the composite. In present study aluminum alloy Al6082 was reinforced with 1% Al2O3 and 3% SiC and 0 to 6% graphite particles by weight. We have varied temperature, speed of agitation and kept all other parameters constant. With present stir casting process, we have successfully processed the total reinforcement up to15% by weight. PAMC has shown 23% increase in hardness, 110% increase in tensile strength and 54% increase in the stiffness. With increase in the graphite reinforcement, coefficient of friction and wear rate of PAMC decreases. Coefficient of friction stabilizes between 0.3 to 0.33 and wear rate stabilizes near to 0.00005 mm3/Nm.

Abstract: In this paper, a finite element model of piezolaminated composite shell structure is developed using nine-noded degenerated shell element. The stiffness, mass and thermo-electro-mechanical coupling effect is incorporated in finite element modeling using first order shear deformation theory and linear piezoelectric theory. The sensor voltage is calculated using the same formulation and fuzzy logic controller is used to calculate the actuator voltage. The fuzzy logic controller is designed as double input-single output (DISO) system using 49 If-Then rules. The performance of fuzzy logic controller is compared with convention constant-gain negative feedback controller. The simulation results illustrate the superiority of fuzzy logic controller over constant-gain negative feedback controller.

Abstract: Diethyl Ether (DEE) is a promising oxygenated renewable bio-base resource fuel for CI engines owing to its high ignition quality. DEE has several favourable properties, including exceptional cetane number, very low self-ignition temperature, high oxygen content, broad flammability limits and reasonable energy density for on-board storage. It is a liquid at ambient conditions, which makes it attractive for fuel handling and fuel infrastructure requirements and hence, it is a compatible fuel for use in CI engine. Diethyl ether is the simplest ether expressed by its chemical formula CH₃CH₂-O-CH₂CH₃, consisting of two ethyl groups bonded to a central oxygen atom. It can be mixed in any proportion in diesel fuel as it is completely miscible with diesel fuel. It was observed that density, kinematic viscosity and calorific value of the blends decreases while the oxygen content and cetane number of the blends increases with the concentration of DEE addition. The presence of DEE increases the front end volatility of the blends and decreases boiling point in comparison to baseline diesel fuel. No significant difference was observed in the tail-end volatility of the blends. The blended fuel retains the desirable physical properties of diesel fuel but includes the cleaner burning capability of DEE.

Abstract: The depletion of ozone layer and green house effects are worldwide problem. Refrigerants are part and source of depletion of ozone layer. As we using these Ecofriendly refrigerants then harm to ozone reduces. These are best option for recently running refrigerants. Eco-friendly refrigerant like hydroflurocarbons and hydrocarbons are replacing chlorofluorocarbons application.CFC is the most important member of CFC refrigerants. This paper, gives alternate to refrigerants that are causes ill effect on environment. Their performance with respect to recently used refrigerant compared. By this comparison benefits of Ecofriendly refrigerants discussed.

Abstract: Due to explosive growth of industrial and agricultural activities, there is rise in pollutants in water including heavy metals and toxic elements. In light of increasing pollution load of environment it is imperative to address this problem by different approaches and means.Of the numerous unit processes, evaluated to control pollution, to a degree, adsorption by GAC is one of the best available broad spectrum technologies. Scavenging of a precious metal such as Nickel, present in aqueous systems can be carried out with or without use of carrier such as 8-hydroxyquinoline (Oxine) and its derivatives on various grades of as received activated carbons. The carrier improves uptake of metal ions by GAC. The adsorption process agrees with the Langmuir and Freundlich models and also obeys pseudo-second order kinetics.