Mechanical Engineering

The rapidly depleting fossil fuels have simulated the worldwide search for the renewable alternative fuels. Our country is an agriculture based one and the production of sugar cane is more. In the production of sugar from sugar cane, alcohol will be produced as a byproduct. This made alcohol as a perfect replacement because these are derived from indigenous sources and are renewable. But with the low cetane number and high self ignition temperatures, the burning of alcohols in the existing diesel engines is difficult because for the vaporization it absorbs more heat from the engine and makes the engine cool and further more ignition delays. This made the ignition of alcohol in the high temperature combustion chambers. So in our work an insulated diesel engine is developed which retains higher temperatures in the combustion chambers and aids for the combustion. This reduces the ignition delays and leads for the complete combustion and further improves the thermal efficiency and reduces the emissions. The complete experimentation has done on a single cylinder 4-stroke water cooled 3.68 KW Kirloskar diesel engine with alcohol as a fuel. Due to lower viscosity of alcohol the fuel injection pressure is reduced to165 bar for the experimentation. In the experimentation it is observed that maximum heat lost through the piston. So three different piston crowns made up of Nimonic alloy, Copper and Brass are tried on the test engine with an objective to find the best one in terms of performance and emissions with alcohol as fuel and the same is compared with aluminum piston. Among all the pistons the brass piston performed well. Further the efficiency of the engine can be improved by providing turbulence in the combustion chamber. So for the experimentation maximum number of nine grooves is made on the brass piston and is tested. For the comparison the engine is also operated with aluminum piston. Out of all these pistons tested, brass Piston with nine grooves is found to be the best in terms of efficiency and emissions.

Two phase closed thermosyphon are often used in heat exchanger equipments because of their high heat transfer capabilities without external power requirements. In the current study, the heat transfer characteristics of two phase closed thermosyphon is analysed experimentally for various angle of inclinations and heat inputs. To carry out the experiment, two copper thermosyphons of length 1000 mm, inner diameter 17 mm and outer diameter 19 mm are taken and charged with 60 ml of working fluid with an evaporator length of 400 mm and condenser length of 450 mm. One of the thermosyphon is charged with de-ionized water (DI) whereas the other is charged with aqueous solution of n-hexanol. The heat transfer coefficient of thermosyphon filled with aqueous solution of n-hexanol shows a better result when compared to thermosyphon filled with de-ionized water.

The Finite Elements Method (FEM) analysis is very helpful in solving a wide variety of engineering problems. An application of finite elements method ranges across many different fields of modern science and of the manufacturing industry. The various applications in aircraft, space, ship building, the electrical and computer industry as well as in the field of science such as material engineering, mechatronics, biochemistry and even medicine must be emphasized. FEA of simulation gives better, more accurate and wider results than experimental methods. One of the examples of FEA application is strain analysis of joints and assembly structures of vehicles of machineries. It allows the kind of stresses occurring in the vehicles and the location their occurrence to be determined. In this study, a methodology of sequentially simulating each step in the manufacturing process of an assembly is proposed. Each step of the proposed methodology is described, and a validation of the prediction capabilities is performed by making a comparison with a physically manufactured assembly. The work presented here demonstrates that by using virtual prototyping it is possible to predict the final shape of an assembled structure. The trial and error development process may be shortened by replacing most of the physical try out with finite element simulation of the manufacturing process. The automotive industry is constantly looking at ways and means of reducing costs and staying profitable while delivering on time. The common denominator in all these challenges is design. Companies investing in developing indigenous design and manufacturing technologies emerge successful in the world market and are able to sustain and innovate at a faster pace than the rest of the competition. This is possible on account of the following capabilities such as delivering products faster with up-front engineering design validation as a part of the product development process while compressing the cycle time, lean design by incorporating value engineering as a part of the design process ensuring evaluation of least cost alternatives before even the first prototype is developed and increasing reliability by design – an initiative that will eliminate hidden costs associated with product recall, re-design and/ or replacement of parts. Increasing functional complexity, predatory pricing, compulsive cost reduction commitments, aggressive deadlines, field failures, warranty costs and product recalls are all too familiar situations in the automotive sector. This leads to greater innovation, process automation, shorter development cycles, design for durability, reduced physical prototypes, improved quality and innovation.

This work has been done in two phases. In the first phase, the controllable parameters (cutting speeds, feed rates, type of drill tool, cutting fluids) which influence the responses (torque, cutting force, surface roughness, material removal rate, power) in drilling of En8 steel are identified and an Artificial Neural Network (ANN) model has been developed to predict the responses. The developed ANN model has been trained and tested with experimental data of drilling process which is conducted under Minimum Quantity Lubrication (MQL) condition. ANN tested results are closely matched with experimental results. In the second phase, the ANN predicted results are analyzed by performing Taguchi’s S/N ratio analysis and optimum combinations of input parameters are determined. Further, the analysis of variance (ANOVA) is employed to find the contribution of input parameters on output parameters. This work is useful in predicting the multi responses while cutting different materials in different processes.

The present research paper examines the factors which a company must consider while implementing Green Supply Chain Management (GSCM) practices. Three companies from Indian “Food and Beverage” (F&B) sector are examined in their approach to be more sustainable. The research method employed is comparative case study analysis. Semi-structured interviews are held with two relevant managers from each company. Top-management support is crucial for effectively working GSCM practices. Employee involvement is recognized as crucial element of GSCM. An environmental friendly company culture is beneficial and should be derived from the companies’ environmental vision and mission. Collaborations with suppliers are perceived to be productive and essential to develop innovative products.

Harvesting solar energy has been the keen focus of study among researchers all over the globe. In the current scenario of fast depleting non-renewable resources, efforts have to be made for maximum utilization of available solar radiations. The present review studies NEILS as one of the front runner as suitable HTF for solar collectors due to their impeccable thermal properties and the various possible reasons for enhancement in heat transfer properties of NEILS.

Supply of power for an implantable medical device through a thermoelectric generator shows potential way for a biological system. The direct utilization of the temperature difference existing whole biological body is the unique feature. This paper attempts to review the energy generation of an implanted thermoelectric generator for various physiological or environmental thermal surroundings. Also several technical approaches included to enhance the energy generation from an implanted thermoelectric generator, to shows its long-term potential energy supplier for such medical practices.

The purpose of this paper is to develop a plan for reducing a lead time in a small scale furniture manufacturing industry by using Value Stream Mapping Technique with Value Engineering. In this paper VSM technique is applied in furniture manufacturing small scale industry to identify the ways of reducing waste while at the same time increasing the proportion of the processes that add value to the product. The wastes in this furniture industry is mostly in the form of over production, transportation and delay. The reasons observed are inadequate coordination among the operators, improper planning, non effective use of machine, improper flow etc. Here the flow process chart is constructed to calculate the number of operation, transportation, delay, inspection and storage with distance travelled by the product for existing and proposed methods in which considerable saving is achieved. Also the Current and Future VSM is created for small scale furniture industry which manufactures office tables. In this the lead time can be reduced considerably with the reduction in NVA time and the process time. There is a considerable rise in VA time of 10.41% with the value addition by modification of the table with less process time.

In recent days, the Fiber Reinforced Composites have replaced many of the engineering components and the composite material manufacturing area is experiencing substantial growth. FRC’s also have replaced materials used in the civil construction area, sporting goods, automobile and aircraft parts, and boat and ship hulls. The composites in general, offer many advantages over homogenous materials like high strength to weight ratio, less weight, flexibility in design, structural and dimensional stability, corrosion and wear resistance along with low tooling cost. Because of the anisotropy in nature, machining composite materials is a complex process especially operations involved in in drilling and milling. Therefore, dry drilling operation on composite materials affects the performance of the drill tool. Hence the present investigation focusses on the study of effect of the machining parameters such as spindle speed (1200, 1500 and 1800 rpm), feed rate (0.1, 0.2 and 0.3 mm/rev), drill diameter (6, 8 and 10mm) on HSS drill tool wear in the drilling of Glass Fiber Reinforced Polyester (GFRP) composites. The present work also aims to optimize the machining parameters in drilling to get minimum flank tool wear. The experiment is designed using full factorial design of experiments. Measure of land width was used to assess the Flank wear of HSS drill. The process parameters are optimized to reduce the tool wear using Response Surface Methodology (RSM). Mathematical model was generated by through regression analysis by developing a Regression equation for flank wear of HSS drill.

Access to energy has been found to affect attainment of sustainable development of a country. Poverty, unemployment, and other developmental problems facing Nigeria have been traced to unavailability of energy for both domestic and industrial purposes. In recent times, government has been active in developing the renewable energy sector to meet the country’s energy need. But this has been hampered by many problems. This paper identify some of these problems, which include absence of policy, legal and regulatory framework, non-existence of framework for Power Purchase Agreements (PPA), weak institutional framework, high initial capital costs, lack of technical or commercial skills and information, public awareness, subsidies for competing fuels , and corruption, and ways of turning the situation around were suggested. The paper however concludes that if the government, private investors, research institutions, various agent of government and the general public can join hands together, these barriers would be overcome and adequate energy provided for the Nigeria citizen.