The effect of pongamia bio diesel blending ratio, compression ratio and injection pressure on emission characteristics of a Variable Ratio Compression ignition engine was investigated. Emission characteristics were studied when the engine was operated using the different blends (B10, B20) and normal diesel fuel (B0). The investigation was carried out to optimize the levels of parameters by Taguchi method. The tests have been designed using an L27orthogonal array with four factors and three levels each. According to the results, compression ratio and bio fuel blend play the significant role on the exhaust emission. Furthermore, the estimated optimum values of the process factors for obtaining lower CO and HC are compression ratio of 21, injection pressure of 180 bar, bio diesel blend of 20%. The result shows that the compression ratio and biodiesel blend % are the most significant factors influencing exhaust emission followed by injection pressure. The results showed that lower CO and HC emission were observed at increased compression ratio. An increase in compression ratio results in decrease in nitrogen oxide emissions.
Keywords: Pongamia bio diesel, Variable Ratio Compression ignition engine, emission, Taguchi method, L27orthogonal array, Analysis of Variance
Concrete is a composite material made from cement, water, fine aggregate and coarse aggregate. But present researchers are interested in finding new cementing materials by waste materials or waste products produced from industries. Metakaolin is a cementitious material used as an admixture to produce high strength and it is used for maintaining the consistency of concrete. The use of plastics is increasing day by day although steps were taken to reduce its consumption. This creates substantial garbage every day which is unhealthy. The cement is partially replaced by metakaolin (2.5%, 5%, 7.5% and 10% by weight) to improve the strength, durability and reduces the porosity of concrete and it is the best way of environmental friendly disposal of plastic. The properties of materials (Physical & Chemical) were studied meanwhile the strength characteristics (M20) such as compressive strength, split tensile strength and flexural strength test results were found by the companion specimens like cubes, cylinders, prisms and beams.
Keywords: Cement, compressive strength Metakaolin, shredded plastic waste, partial replacement, split tensile strength and flexural strength
Better sliding lubricating effect of graphite in aluminum/graphite composites makes them to be used as self-lubricating materials in industrial and automobile areas. Sliding contacts such as piston, bearings, sheaves, cylinder liners etc. uses such composites in order to reduce the external lubricant consumption and to achieve better sliding lubricant effect. This also helps to minimise the use of external toxic petroleum based lubricants in sliding contacts for better environment and decrease wastage of energy in automobile and industrial components. But due to the graphite content, deterioration in mechanical properties of Al/Gr composites occurs. This problem can be avoided by adding hard reinforcement particles to Al/Gr composites and thus making the composite hybrid. Due to excellent properties, boron carbide particles with varying wt % of 3, 5 and 7 are used for preparation of hybrid composite. LM13 aluminium alloy is the matrix material used. Stir casting technique is employed for the preparation of Al/Gr 2% and Al/B4C/Gr 2% composites. Using CREO a 3D piston model was created and Static structural analysis of unreinforced aluminium alloy, Al/Gr self lubricating composite and Al/B4C/Gr hybrid aluminium composites are performed using ANSYS 14.5 workbench software. Better static structural properties were observed for Al/B4C/Gr composites compared to the self lubricating composite.
Keywords: Boron carbide, Graphite, Hybrid aluminium matrix composite, LM13
Composite sections are more extensively used in foreign countries to attain more structural efficiency, Cold-formed sheets are used to decrease the dead load and thereby adding additional tension reinforcement it can take heavy loads and improve the structural efficiency. Therefore cold formed fabricated sections with concrete acts as an effecting lateral restraint and further increasing load carrying capacity of beam by using self-compacting concrete of grade M30. The bar surface acts as a cover for the web and improves as fire resistance to the section to a certain extract. They ensure a better yield strength and also against shear buckling much liberation shows the effecting coverage of thin composite sections.
Keywords: Composites Sections, Cold formed sheets, self-compacting concrete, fire resistance, yield strength
Self-compacting concrete (SCC) compromises over the Normally Compacted concrete (NCC) with diverse uses, predominantly the annihilation of vibration and unity in placement. It also confirms to be active in closely arrayed reinforcement bars and in zones where it is incomparably uncertain to compact by using vibrators. SCC is cast by decreasing the ratio of the volume of coarse aggregates to powder content (Cementitious materials), thereby improving the volume of paste by adding various viscosity modifying and water reducing admixtures. It is noted that the performance of the design concrete mix is significantly influenced by the difference in moisture and temperature both in the fresh and hardened state. Curing techniques and curing span significantly influence “curing performance”. Procedures used in concrete curing are principally classified into two groups particularly, Water adding techniques and Water- retraining techniques. In the current research, the influence of few chosen curing methods on the mechanical characteristics of self-compacting concrete (SCC) of grade M30 and M50 have been investigated. In the first stage, numerous investigations are conducted with 0.01 m3 of concrete with the application of locally obtainable materials and checked the fresh characteristic analyses according to the standards of European Guidelines and concluded the mix proportion of M30 and M50 grades of SCC, given as a reference SCC mix. In the second stage, the mechanical characteristics including compressive, tensile and flexural strengths affected by several curing methods such as normal water immersion, hot water, ice, seawater and wet covering, will be examined.
Keywords: SCC, admixtures, Water- retraining, mechanical characteristics
Friction Stir Welding (FSW) is the solid state green welding Technique. In which the materials are welded not by melting and recasting. To decide the joint characteristics the major welding parameters of the rotational speed, welding speed and the axial load are taken in to account. In this experimental study the central Composite Circumscribed (CCC) design technique and the mathematical model was developed by using the Response Surface Methodology (RSM). In this experimental analysis 3 major parameters and 5 levels with 20 FSW weld runs are used for the development of the relationship between the FSW parameters of the tool rotational speed, the welding speed and the axial load and the responses of the tensile strength, yield strength, Percentage of elongation and the hardness are established.
Keywords: Friction stir welding, welding parameters, mechanical properties, Mathematical model, Response Surface Methodology
Aluminium based metal matrix composites are used as an unconventional material in the transport, defense, aerospace, automobile, marine applications because of their improved high hardness, stiffness, wear resistance and better temperature resistance. With their combined mechanical and wear characteristics, composites are replacing the conventional materials in the manufacturing industries. Particle reinforced composites have better forming capacity than the fiber or whisker reinforcement. Ceramic materials like SiC and alumina are widely used as reinforcements. Among the different processing techniques, stir casting method seems to be the easier and cost efficient. In this paper the effect of reinforcement and its particle size on the mechanical and tribological properties of aluminium matrix composites are reviewed. The results of the researchers indicate that the addition of reinforcement increases the mechanical and tribological properties of the composites. Fine particle reinforcement exhibits superior mechanical properties whereas the coarse particle reinforcement exhibits maximum wear resistance.
Keywords: Metal matrix composites, Particle size, Stir casting, Reinforcement, Wear resistance