Mechanical Engineering

In this paper, some engineering properties of sugar cane stalk are determined. For this purpose, two varieties of sugar cane including L310 and L820 varieties with average moisture contents of 76.4 and 73.8% wet basis, respectively, were used. The experiments were conducted at ten internode positions down from the flower for both varieties. Based on the results obtained, the averages of stalk’s diameter, cross-section area and second moment of area of L310 variety were higher than those of L820 variety, while the average of stalk’s length of L820 variety was higher than that of L310 variety. The internode position had no significant effect on the shearing and bending properties of both varieties. Furthermore, there was significant difference between the two varieties in the case of Young’s modulus, while there was not any difference in the case of shear strength, specific shearing energy and bending strength. The average of Young’s modulus of L820 variety was significantly higher than that of L310 variety. The mean values of shear strength, specific shearing energy, bending strength, and Young’s modulus of L310 and L820 varieties were obtained as 4.92 and 5.25 MPa, 53.36 and 57.35 mJ mm^-2,  9.58 and 9.20 MPa, and 18.81 and 24.50 MPa, respectively.

Efficient energy conversion devices are the most important need of the hour looking at the global energy scenario. Catering to this need, better and more efficient designs are been put forward regularly. New and better methods of energy conversion are also been proposed. The use of Turbocharger in an engine is an example of the same. But the critical examination and of these devices is of utmost importance. Simulation is a tool that can reduce the efforts that need to be put in physically and can carry out virtual calculations and can respond the results too. There are various pre-programmed software that contain a variety of models that can be employed to study the parametric variation and carry out the simulation. This paper deals with study of three such turbulence models namely the k-epsilon, k-omega and the Shear Stress Transport model. A number of parameters will be considered and simulations will be carried out on all the three models with the view of determining the most suitable model among the three with the ability to provide optimum results for the study of a turbocharger turbine stator optimized for producer gas. The results will be obtained in the form of graphs and contour images which will be studied to determine the most suitable model for further use. Based on the results, suitable conclusion will be drawn and stated towards the end.

A four stroke spark ignition engine is a mechanical engine in which its operation completes by four strokes or movements of piston in the engine cylinder. This engine can also be called gasoline or petrol engine because its basic fuel is gasoline but nowadays, alternative fuels are being considered as the engine operating fuel. The alternative can be mixture of gasoline with other hydrocarbon products like ethanol or singly be another hydrocarbon product that can offer a better performance and lesser consumption when compared with gasoline. Though, the alternative fuels offer lesser consumption but it can also be intensified by considering the engine design specification for better performance which led to the birth of this work. Compression ratio of the engine determines the engine performance, the higher the compression ratio, the greater the efficiency of a spark ignition engine. In ordinary gasoline fuel, higher compression ratio can infer another engine problem like knocking and emission of toxic combustion product but the alternative fuels have been developed to lessen all these effects. The aim of this work was to simulate the influence of compression ratio on an alternative fueled four-stroke spark ignition engine using C# computer program. The simulation model was carried out under assumed varying compression ratio; 4.63, 5.10, 6.00, 6.88, 7.40, 8.28, 9.16, 9.94, 10.45, 10.98 and 11.44, from this, the volume relationship was determined. The mathematical engine simulation model was carried out using thermodynamics-based models. The result of the simulation showed that higher compression gives higher efficiency and the numerical values are in close agreement with experimental values. The percentage error is not more that 2% during combustion duration and efficiency as compared with experimental values. From the numerical results, it was observed that if the compression ratio is high, the crank angle will also be high and this will make the ignition delay period to be diminished. This also goes for the engine performance, power output or the efficiency, the higher the compression ratio the greater the efficiency. Therefore, an alternative fueled engine with compression ratio of 9.16 and above will have a greater efficiency.

Bicycle is recognized as a transportation solution helping to improve various environmental, economical and social aspects. A variety of bicycle design and setups for utility are used to carry personal belongings, groceries, children and much more. One particular utility bicycle is the folding bicycle. Its design allows users to easily transport the bicycle using less space when the bicycle is “folded” in to a compact size. When using a folding bicycle with a bicycle-transit journey, it allows individuals ability to board transit vehicles. The versatility of a folding bicycle is also appropriate for air travel and for when inadequate parking and bicycle theft is a significant concern.

Recently, the issue of machine condition monitoring became global due to the potential advantages to be obtained from decreased maintenance costs, improved productivity and increased machine availability. Vibration technique in a machine condition monitoring provides useful reliable information, bringing significant cost benefits to industry. By comparing the signals of a machine running in normal and faulty conditions, detection of fault like journal-bearing defect is possible. This paper deal a new method of engine journal-bearing fault diagnosis based on Power Spectral Density (PSD) of vibration signals in combination with Support Vector Machine (SVM). The frequency domain vibration signals of an internal combustion engine (IC engine) with three main journal-bearing conditions were gained, corresponding to, (i) normal, (ii) corrosion and (iii) excessive wear. The features of PSD values of vibration signals were extracted using statistical and vibration parameters. The extracted features were used as inputs to the SVM for three-class identification. The roles of PSD technique and SVM classifier were investigated. Results showed that the accuracy rate of fault diagnosis of the IC engine main journal-bearing was 100%. The results demonstrate that the proposed method has the potential for fault diagnosis of main journal-bearing of IC engine.

Carburizing, though a widely used industrial thermo chemical diffusion process, it is associated with the problem of shape and size distortion in the carburized parts.  These distortions are troublesome as they adversely affect the performance of the parts in terms of life, and trouble free operation. The main objective of our present work is to optimize the distortion level, optimum case depth, and surface hardness value of the carburized parts made of EN 353 material. Taguchi’s mixed level series Design of Experiment was selected for optimization.  The significance of our study was that all the three stages of carburizing (Pre carburizing, Carburizing and Post carburizing) were considered for optimization.  An orthogonal array and ANOVA were employed to investigate the influence of major parameters on the three response variables namely Distortion level, Surface hardness and Case depth and optimum conditions were arrived at by applying high penetration depth, high hardness and low distortion are better as the strategies.

Groundwater resources are essential to maintain a stable water supply to growing cities for the efficient farming region and for domestic purpose. Due to simplicity of the techniques, the Vertical Electrical Sounding (VES) has proved very popular with groundwater prospecting and engineering investigations. The main objective of the investigation is to delineate the subsurface lithology and to assess the groundwater resources of the study area. It also aims to focus on the identification of fracture zone and its thickness by using VES method. The life of a button bit in bore well drilling depends mainly on hardness of rock. As the hardness varies at different locations, the reliability of the button bit also varies accordingly. In order to arrive at the reliability, the life of the button bit in terms of depth of drilling has to be obtained. This can be converted in terms of time from the known velocity of drilling. It is proposed to arrive at the drill bit reliability from the obtained failure rate.

Evaluation of 20 min. shot peening surface treatment on fatigue strength of 6063-T6 Al allay is presented under 3.5% NaCl solution from one day, one week and one month under room temperature and stress ratio R= -1. The results show that the shot peening has strong effect on the fatigue strength at 107 cycles for corroded specimens. In case of shot peening ,only 17.5% loss in fatigue strength even after submerging for one week compared with 60% of the fatigue strength was reduced in case of un shotted specimen . But for one month pre – corroded specimens, the fatigue strength was reduced by 64% in corrosion environment while shot peening improved the above reduction to be about 44%.

In the present work, cost of the weld is minimized by considering the qualities of weld (strength parameters). Welded joints are prepared with Mild Steel plates and M.S electrodes. Strength properties of welded joints like tensile stress, shear stress are found by conducting experiments with Universal Testing Machine (UTM). An objective function is formulated for minimization cost in terms of geometric properties of weld, where as constraints are formulated in terms of strength properties. The optimization procedure involves the selection of the major geometric parameters such as length of weld, height of weld, depth of weld, width of weld and minimization of cost is considered as the design target. In the present work Mat Lab programs of SA and PSO are developed and executed using weld and test data and the results are compared.

A data acquisition system is a device designed to measure various parameters. The purpose of the data acquisition system is generally the analysis of the data and the improvement in accuracy of measurements. The data acquisition system is normally electronics based, and it is made of hardware and software. The hardware part is made of sensors, signal conditioners & data acquisition card and computer. The data acquisition system increases efficiency of measurement and lowers the cost for test, through easy to integrate software like Visual Basic. With this system, Engineers can use graphical representation to meet their specific needs – very different from the conventional and traditional measurements. Additionally, data acquisition system capitalized on the ever-increasing performance of personal computers. In test, measurement, and control, the system experiences up to a 10 times increase in efficiency at a fraction of the cost, in a fraction of time, of traditional measurement system. This Dissertation work involves testing of internal combustion engine using data acquisition system . For this the data is acquired from internal combustion engine and send to computer after required conditioning. The parameters of internal combustion engine which can be measured are speed, load, temperature and vibrations . The graphical display on the computer screen can be made by using any software like Visual Basic . This is an attempt to develop a Computerized Test Rig for measurements of Speed , Load & Temperature, Vibrations using Software like Visual Basic , Hardware PCI 1050 Card with Signal Conditioning using INA128 IC and Sensors like Proximity Sensor, Load Cell and RTD .