Mechanical Engineering

This paper analytically examines the effects of adding nanoparticles on the exergy destruction of water– Al₂O₃ nanofluid flow through a circular duct under constant wall heat flux for thermally and hydrodynamic laminar regime. The single phase model is employed to simulate the nanofluid convection, taking into account appropriate thermophysical properties. Particles are assumed spherical with a diameter equal to 13 nm and are easily fluidized. In this approach, nanofluid can be treated as a pure fluid. Results show that with increasing the volume concentration of particles, the values of both of exergy transfer and heat transfer rate, decreases, especially for lower values of Reynolds number. These results indicate that along the duct at a fixed volume concentration, exergy destruction, decreases.

This Magnetic Braking Systems (MBS) project summary is written to explain the importance and needs of product development of MBS for vehicle (motorcycle) and MBS Learning tools by utilizing the Project Based Learning (PjBL) via eSOLMS of producing innovative product (automotive). This concept aims to improve the braking system by using magnetic concept. Its focus on 3 aspects; 1) to producing alternative product for vehicle braking system (motocycle brake system), 2) to producing learning tools in advance automotive focus on magnetic braking system, 3) to developt self-regulation of engineering students (automotive) for producing an innovative product (MBS) focus on PjBL:eSOLMS concept. This project was focus on both automotive project development and 21 century e-learning process in nature. The product producing data was analyzed using standard engineeing forms or automotive lab sheet collection data. A total of 2 product; MBS for motocycle and MBS learning tool will intering 18-25 weeks for pilot test. The finding will shows the important and needs of product research and development of MBS in future. On the other hand, the result of lab/workshop measurement and observation on the usage for the MBS on vihacle and using MBS as learning tool hopefully effected on the development of engineering students’ self-regulation. It is hoped that the MBS concept can be further developed and implemented in the engineering advance automotive and Outcome Based Education (OBE) system of Malaysia.

In the present context, the world is confronted with the twin crisis of fossil fuel and environmental degradation. The fuel economy is achieved by efficient combustion inside the cylinder which is possible by uniform mixing of air and fuel in the cylinder. The swirl can be generated in the diesel engine by modifying three parameters in the engine; they are the cylinder head, the piston crown, and the inlet manifold. The objective of the present study is to enhance the swirl effect in the cylinder which causes better performance and reduces the emissions. In this work an attempt is made using fixed curved blade with different inclinations placed before the intake manifold for effective air swirl motion. For this, the experiment is done on Kirloskar AV1 water cooled, natural aspirated direct injection diesel engine with pure diesel.

This paper gives the brief out line about the worldwide production cottonseed & its oil, Cotton Seed Oil (CSO) properties, its comparison with diesel and Jatropha biodiesel. It investigates the performance of a diesel engine using diesel fuel and cottonseed oil (CSO) biodiesel in terms of brake thermal efficiency and indicated thermal efficiency for conventional diesel, cottonseed oil, as well as for Jatropha oil. For this aim, A Single Cylinder, 4-stroke vertical, water-cooled, self-governed diesel engine developing 5 HP at 1500 rpm (Rope brake dynamometer with spring balances and loading screw. Brake drum diameter = 0.400 m.) engine is selected for the testing with diesel fuel and neat bio-diesel, which is cottonseed oil methyl ester, at full load conditions. The evaluation of theoretical data showed that the brake thermal efficiency and indicated thermal efficiency of CSO biodiesel was slightly higher than that of diesel fuel and Jatropha oil. This study reveals that the use of cottonseed oil biodiesel improves the performance parameters of CI engine compared to conventional diesel fuel.

Titanium workpiece has been machined by Electrochemical Machining in 5.0 M NaCl electrolyte. Dependence of material removal rate on current densities has been determined and compared with theoretical values. It is interesting to note that the dissolution valence decreases with increase in current density. The electrochemical reactions occurring at cathode & anode have also studied .The Electrochemical machining parameters are optimized for maximum material removal rate and better surface finish.

Cellular Manufacturing System (CMS) is an application of Group Technology (GT) in which functionally dissimilar machines are grouped together to form a family of parts. This work gives an overview of the Back Propagation Network (BPN) based approaches to form the machine cells and component grouping for minimizing the exceptional elements and bottleneck machines. This method is applied to the known benchmark problems found in literature, and it is found to be equal or best when compared to in terms of minimizing number of exceptional elements.

This is the study to evaluate the performance of new design of biogas unit and to enhance the biogas production by using different parameters. The raw material to be fed in digester will be the food waste which gets generated everyday from restaurant full of crowd in the locality. With this unit, biogas equivalent to two kg of LPG can be generated from the feeding of approximately 15 kg of food waste every day. This is the only design available which allows the user to choose how much biogas pressure he wants. Biogas thus produced can be checked for quality by different inoculums and additives. Thus the cost of disposing the food waste can be saved and the energy can also be recreated and reutilized for restaurant benefits. Hence the atmospheric contamination automatically gets prevented.

An electrochemical pulse technique have been used to make micro holes on conducting stainless steel substrate. The method is based on the application of ultra short nanosecond voltage pulses where electrochemical reactions are locally confined with sub micrometer precision. Due to gentle removal of the material the grain structure of the material is revealed without any chemical and mechanical modifications. Electrochemical micro machining is based on the finite charging time of the electrochemical double layer capacity on the electrode surfaces due to the finite electrolyte resistance. The machining precision depends upon the electrochemical reactions and related to the pulse length. The design and fabrication of a unique electrochemical machining production system capable of micro and nano scale drilling have been presented for conducting stainless surface. Benchmarking prototype tool against existing micro and nano fabrication tool have been designed. The optimization of the process parameters, electrolyte concentration and solution conductivity have been presented.

Transferring heat using conduction and convection requires the presence of a temperature gradient in some form of matter ,while the heat transfer by thermal radiation requires no matter. It is extremely important process, and from physical sense it is perhaps the most interesting form of the heat transfer modes. It is relevant to many industrial heating, cooling, and drying processes, as well as to energy conversion methods that involves fossil fuel combustion and solar radiation. In this paper, our objective is studying the radiation in Circular Finned-tube heat exchanger. Finned-tube heat exchangers are predominantly used in space conditioning systems, as well as other applications requiring heat exchange between two fluids. One important widespread use is in cooling applications. The results show that the heat transfer in the mode of the radiation is just about 2% compared with forced convection , but when there is natural convection in the system the term of radiation is considerable.

A Multi Hole pressure Probes (MHP) with five holes and conically shaped was designed for Air craft data sensors for calibrating the total pressure, static pressure, flow angle and flow speed. The main principle of five-hole probe is based on the notion that Mach number, pressure and directionality of the incoming stream may correlated with the combination of pressure readings. The general aspects of the five-hole conical probe were studied by various research papers and concluded with the final design of conical probe with 600 included angles which is applicable Air craft data sensors and also for both subsonic and supersonic wind tunnel test sections. Numerical calibration using ANSYS FLUENT 14.0 is done.