DEPARTMENT OF MECHANICAL ENGINEERING
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Item A technical and economic evaluation of the electricity generation and distribution system in Nigeria(2002) Diji, C. J.Electricity is one form of energy . It occupies a special place in our civilization, because it is easier to use than many other types. It is clean, versatile and can be transported over long distances almost instantly. These factors account for why electricity has grown faster than other forms of energy and why this growth is' expected to continue. Electricity generation and distribution in Nigeria is a business of government and government vested that sole responsibility to the National Electric Power Authority (NEPA). Almost 30yrs of its existence, NEPA has not been able to meet the electricity needs for residential, commercial and industrial use. This paper is an exploratory appraisal of the economic and technical factors that has been responsible for the inability of NEPA to fulfil its statutory responsibility. The paper ,asserts that if the issues of electricity demand' and supply, electricity tariffs, choice of technology for power generation and the efficiency of the electricity distribution networks are not addressed, the adequate supply of electricity in Nigeria will continue to be a mirage.Item Energy-Exergy analysis and carbon emission of Nigerian cement manufacturing industry(2009-04) Diji, C. J.; Fagbenle, L.Two of the largest cement manufacturing plants in Nigeria, named Plants A and B, were studied and the data collected for the 10 year period 1995- 2005 from them enabled an analysis of their energy consumption, energy cost per tonne, efficiency of energy use from exergy analysis, and carbon dioxide emission rates. The two plants account for over 70% of total local cement production in Nigeria. Both plants utilize thermal and electrical energy. With both plants having thermal to electrical energy utilization ratio of 90:10 compared to the 70:30 recommended best global practice. The Input-Output Analysis methodology was used to evaluate the embodied energy intensity which was found to increase over the period in both plants, with Plant A having the highest increase from 7.1 to 9.4 GJ/tonne. The embodied energy intensity for both plants was 50% higher than the recommended best global practice of between 2.9 and 3.2 GJ/tonne. The energy cost per tonne for both plants increased by about 1000%over the period despite a 33% reduction in total energy consumption. Efficiency of energy use evaluated from an exergy analysis in Plant A increased from 50% to 59% while in Plant B the increase was from 33%to 45% over the period, compared to the recommended global best practice of 50%. Carbon dioxide emission in both plants declined over the period, for Plant A from 765903 Tg to 548310 Tg (40%) and for Plant B from 604255 Tg to 543658 Tg (16%) over the period.Item Electricity demand and consumption in a manufacturing industry(2002-02) Diji, C. J.; Okiwelu, A. A.Industrialization the world over owes its growth to the discovery of electricity. Most machines and plants are driven by electric motors; residential and industrial lighting is predominantly electrical; and the communication and entertainment industry are largely dependent 011 electricity. This paper is an analysis of the demand and consumption pattern of electricity in a manufacturing industry in Ibadan. Based on the supply pattern of the electricity to meet the needs of the organization; the paper concludes that there is a need to improve electricity supply to tile manufacturing industry to cut down its production cost which has been on the increase due to energy as one of its prime causes.Item Ceramic engines: material properties for higher performance(1998) Simolowo, O. E.The four-stroke reciprocating internal combustion engine has been used as a case study, being that commonly utilized in most automobiles. General properties of ceramics were discussed while exposure was given to some high-performance ceramics. Theoretical deduction and analysis were then carried out to show improved engine performance using ceramic component. the engine performance parameter considered are:(i)power output (ii) mean effective pressure(iii) speed of engine rotation and (iv) mechanical efficiency. analysis based on ceramic properties showed that ceramics such as silicon carbide (SiC), silicon nitride(Si3N4), zirconia (ZrO2) and , titanium oxide (TiO2) proved to have more favourable properties for most engine parts when subjected to engine conditions where they are located as compared to their metallic, steel and alloy counterparts. Though much work has been done in the production of ceramic engines, predictions as to developing (i) adiabatic ceremic engines and (ii) turbo compounded engine show the extent to work that still needs to be done in this area of developing ceramic engines.Item The effect of tribological processes on productivity: a case study of industries in Ibadan metropolis of Nigeria(2009-05) Simolowo, O. E.; Adeniji, O. O.This study analyzed the connection between tribological and other forms of processes in manufacturing industries to productivity in such outfits. Results from the study showed that 54% of the visited industries recorded the highest hours of downtime due to tribological processes, while,15% and 31% of the industries had the highest downtimes hours resulting from electrical and other processes respectively. Also 23% of the total industries were observed to have more electrical faults, 31% recorded highest tribological issues, while 46% had more of non-tribological non-electrical faults.Item Profile simulation software for trigonometric and polynomial cams design(2007) Simolowo, O. E.; Bamiro, O. A.This paper discusses the development of unique software for the design of various cam profiles for the plate cam operating a flat face follower. The method employed in this work is that of generating geometrical cam coordinates using standard cam motions, thereby avoiding the problem of undercutting resulting from graphical layout methds for similar cam and follower types. Determination of critical design output parameters were carried out by the developed software computational algorigthm. The software was validated by using it to simulate a number of standard cases. For the standard case having the follower profile Dwell(200o)-Rise (280o)-Dwell(300o)-Return(360o)and performing cycloid rise and return motion, the prime circle radius for the cam profile and face width of the follower were calculated as 55.72mm and 33.76mm while the maximum and minimum follower velocities were 13.70mm/rad and -10.27mm/rad respectively. These values, as well as those obtained for other standard cases simulated, were found to be in agreement with earlier works done in this area of researchItem Roller-cam systems design: development of a profile analysis software(2009-05) Simolowo, O. E.; Bamiro, O. E.The different options involved in cam systems design such as types of cams and followers, number of applicable standard cam functions, divisions of follower motion-segments, and possible combinations of follower displacement profiles, among others, were critically studied to determine the structure and capabilities of a software package suited for extensive design analyses. The software was applied in the design of cam profiles with selected follower and cam functions and the results obtained were found comparable with those obtained from numerical methods and existing software packages.Item The development of an analyses-intensive software for improved cams systems design(2008-04) Simolowo, O. E.; Bamiro, O. A.The computer-aided software developed in this research work is used in designing cam systems by generating various follower motions and cam profiles. It is highly suited for extensive dynamics, kinematics and geometric design analysis based on some inherent features that are unique. The plate cam with either flat-face or roller followers can be designed. Most of the standard and acceptable cam functions are included such as double harmonic, modified trapezoidal, cycloid, 4-5-6 polynomial and others. Various prime circle radii and follower face widths are calculated for flat-face follower design option for any user selected cam angle, follower profile and cam function. Other parameters such as minimum and maximum values of radii of curvature, pressure angle, are also calculated for roller follower design option. In every design the follower motion and cam profiles are calculated and coordinate files can be exported in Cartesian format and automatically imported into a spreadsheet package thereby using all its features for better analysis of results. All dynamic, kinematics and geometric parameters can be plotted and all data may be printed to the screen, to a printer, or to a file.Item Design and simulation algorithm for cam system analysis(2004-12) Simolowo, O. E; Olaniyi, M.Computational algorithm and various computer aided methods are now routinely being used in the design of numerous kinds of engineering systems, sybsystems and components. In particular some of these computational methods perform dynamic and kinematic analysis of mechanisms. In this work an algorithm for the design and profile simulation of plate cam with flat-face followes using standard cam motions has been developed. The developed algorithm computers the two critical design output parameters among others namely; the prime circle radius and follewer face width, and finally generates the cam coordinates for the cam profile being designed. The design algorithm developed in this work makes the design of cam systems less tedious, thereby, making various extensive studies o the comparative design analysis of such systems possible.Item Effect of desing parameters on CAM profiles(2003) Simolowo, O. E.; Udoh, E. A."In the process of generating a cam profile, input parameters such as lift maximum allowable pressure angle, eccentricity and roller radius are subjected to variations. These variations are done in order to arrive at optimum output design parameters, cam profiles and ultimately optimum cam design. A computer aided analysis of cam profiles with eight - order - polynomial motion using a roller follower and having a Dwell- Rise - Return. displacement profile has therefore being carried out in this work. The analysis, in a similar procedure, is also applicable to cam profiles with different standard cam motions, followers, displacement profiles and cam angles. The followers lift, maximum allowable pressure angle, eccentricity and roller radius were varied within and outside design limits and their effects ana lysed on the generated cam profiles and other design parameters. Optimum values for the parameters considered were obtained from the result of the variation analysis, while characteristic changes were also observed from the generated cam profiles. "