Department of Mechanical Engineering

Permanent URI for this community

https://kwasuspace.kwasu.edu.ng/handle/123456789/92

Browse

Now showing 1 - 20 of 105

2D Flow around a Rectangular Cylinder: A Computational Study
(AFRREV STECH: An International Journal of Science and Technology, 2013-01-01) A.S., Olawore; I.F., Odesola
The unsteady flow around a rectangular cylinder is an area of great research for scientist for several years. A two-dimensional unsteady flow past a rectangular cylinder has been investigated numerically for the low Reynolds numbers (flow is laminar). Gambit has been used throughout this work to generate the geometry and meshes and the computational fluid dynamics analysis is done using fluent software. The influence of vortical structure and pressure distribution around the section of rectangular cylinders are examined and reported. The integral aerodynamic parameters are also reported. Strouhal numbers for Reynolds numbers of 55, 75, 100, 150, 250 and 400 are 0.102, 0.122, 0.129, 0.136, 0.139 and 0.158 respectively. The magnitudes of the coefficient of drag for the Reynolds numbers are 1.565, 1.524, 1.432, 1.423, 1.526 and 1.545. The lift coefficient for flow around a rectangular cylinder with a chord-to-depth ratio equal to 5 of low Reynolds numbers of 55, 75, 100, 150, 250 and 400 are 0.067, 0.101, 0.157, 0.212, 0.404 and 0.537 respectively. The pressure drags obtained in the simulations at zero angle of incidence are 1.446, 1.455, 1.439, 1.412, 1.579 and 1.602 for Reynolds numbers 55, 75, 100, 150, 225, and 250. The velocity across the rectangular cylinders varies from 0.089 to 1.02m/s. The forces caused by vortex shedding phenomenon must be taken into account when designing buildings for safe, effective and economical engineering designs.
3D Flow around a Rectangular Cylinder: a review
(AFRREV STECH, Vol. 1 (2) April-July, 2012, 2012-04-01) Odesola, Isaac F.; Olawore, Ayodeji
Turbulent flows around three-dimensional obstacles are common in nature and occur in many applications including flow around tall buildings, vehicles and computer chips. Understanding and predicting the properties of these flows are necessary for safe, effective and economical engineering designs. This paper presents the review of 3D flow around a rectangular cylinder using large eddy simulation as the turbulence model and the computational study is developed in the frame of the Benchmark on the Aerodynamics of a Rectangular Cylinder (BARC). Different simulations around bluff bodies were reviewed and the results obtained through different methodologies are presented. The effect of change by vortex shedding on the magnitude of fluid forces of rectangular cylinders are examined and reported. The aerodynamic integral parameters obtained from different papers are compared.
A BRIEF REVIEW OF CHARACTERISTICS AND APPLICATIONS OF SHAPE MEMORY ALLOYS IN ENGINEERING AND RELATED FIELDS
(International Journal of Mechanical Engineering and Technology (IJMET), 2021-09) Issa, W. A.; Camur, H.; Savas, M.
Shape Memory Alloys shortened as SMA’s are examples of smart materials. They sense and respond to changes in environmental conditions or stimuli, such as chemical, electrical, mechanical among others. This review, discusses the concept of SMA’s, including their engineering effects and innovations in SMA’s research. Similarly, the uses and applications of SMA’s in engineering and related fields such aerospace, biomedical, chemical, civil, electrical, and mechanical engineering are reviewed briefly including the merits and demerits of using SMA’s
A GIS – based method for assessment and mapping of noise pollution in Ota metropolis, Nigeria
(Method Article, 2019) S.O. Oyedepo; G.A. Adeyemi; O.C. Olawole; O.I. Ohijeagbon; O.K. Fagbem; R. Solomon; S.O. Ongbali; O.P. Babalola; J.O. Dirisua; U.K. Efemwenkiekie; T. Adekeye; C.N. Nwaokocha
A review of solar air heater for drying of agricultural products
(Advanced Materials Research, 2014-02-27) Kareem, M.W.
Bulk of farm products need to be preserved because of their perishable nature. The cheapest and environmental friendly means is indirect usage of solar irradiance to reduce the moisture content of these products to a level that cannot sustain the activities of micro-organisms. The research on solar collector has gained its popularity over the years due to man’s quest for green energy which has led to increase in demand for the utilization of solar energy. Harnessing of solar energy by man for drying purposes was predominantly by direct method which reduces the quality and quantity of the dried products. This work presents the most recent contributions on solar air heater of flat plate absorber category. Various models, material of component parts and performance efficiency of these air heaters were discussed and there is need for collector optimization. The study was concluded with a focus on multiple pass approach of solar harvesting.
A Review on MHD Mixed Convection with Nanofluids in Regular and Irregular Geometries
(Journal of Thermal Energy Systems, 2023) Adekeye T; Okekunle P. O; Adegun I. K
A Study on Energy Demand and Consumption in Covenant University, Ota, Nigeria
(Covenant University, 2015) Oyedepo, S. 0; Adekeye T; Lerarno, R.O; Kilanko, 0; Babalola, O.P; Balogun A. 0; Akhibi M. 0
Analysis of Two Dimensional Heat Transfer Problem Using Spreadsheet Approach
(Energy Technology and Management conference, 2012) A.A Oladosu; I.F Odesola; A.S Olawore
The storage of thermal energy in the form of sensible and latent heat has become an important aspect of energy management with the emphasis on efficient use and conservation of the waste heat and solar energy in industry and buildings. Heat storage materials absorb heat through standard heat transfer mechanisms, e.g., radiation, conduction, and convection. The need for developing software for solving these problems become imperative because it has necessary functions for solving a large class of engineering problems. The aim of this project is to demonstrate how Spreadsheet can be used for solving heat transfer problems in an arbitrary geometry. Survey was carried out on various geometries. An example considered was a chimney. The symmetry of the geometry was considered. Energy balances were obtained and finite difference formulations were made. Finite difference equations for various nodes were determined. Spreadsheet was set up for the problem. Various temperature distributions were obtained. Temperatures are highest at the inner wall (but less than 300oC) and the lowest at the outer wall (but more than 260 k), as expected. The average temperature at the outer surface of the chimney was 352.65k. The rate of heat loss through the 1m long section of the chimney was determined both manually and numerically.
Application of Response Surface Methodology (RSM) for the optimization of energy generation from Jebba hydro-power plant, Nigeria
(2020-08-16) A.O. Onokwai, H.I. Owamah, M.O.Ibiwoye, G.C. Ayuba and O.A. Olayemi
This research was performed to optimize the performance characteristics of the Nigerian Jebba Hydropower Plant in order to enhance its generation of electricity. Pertinent hydropower data were hourly collected from the plant from 8:00 am to 5:00 pm between 2016 and 2018. The coefficient of determination obtained from the response surface methodology (RSM) showed that discharge, pressure drop, stator temperature and water pressure strongly influenced the generation of estimated power. Also, the contour and surface plots suggested that the discharge (D) 8200.00–8600.00 m3/s and pressure drop (Pd) ranging from 27.50–28.50 m gave the optimal power generation indicating that both factors must be kept high when the hydropower plant is in operation. The instability of power generation was attributed to the reduction in the net available head as turbine inlet decreased. The study, therefore, showed that net power output, speed of the turbine, and efficiency of the hydropower plant could be optimized with increase discharge and gross head. Predicted optimal values for discharge, pressure drop, stator temperature, and water pressure were 8783.3667 m3, 28.59 m, 58.00°C, and 31.00 N/m2 respectively.
Assessment of Energy Saving Potentials in Covenant University, Nigeria
(Energy Engineering, 2016) Oyedepo, S.O; Adekeye, T; Leramo, R.O; Kilanko, O; Babalola, O.P; Balogun, A.O; Akhibi, M.O
Bioconvection analysis for convectively heated radiative flow of Sutterby fluid involving efficacy of ferromagnetic nanoparticles
(Elsevier, 2024-08-16) Muhammad Tabrez; Amjad Ali Pasha; Waqar Azeem Khan; Iftikhar Hussain; Salem Algarni; Talal Alqahtani; Kareem, M.W.; Mehboob Ali
In this article explained about the study 2-D Sutterby fluid model with suspension of microorganisms in ferrofluid, while radiation aspect is also considered here. Basic purpose of using microorganism is to obtain more stability in suspension. Here the important characteristics of thermophoresis parameter, viscous dissipation, magnetic interaction parameter and Brownian motion parameter are examined. Now, the system of non-linear P. D.Es is changed into set of O.D.Es then we solved these equations by using famous mathematical scheme bvp4c. Graphical results showed that temperature of Sutterby ferrofluid intensifies with increase in the estimations of thermal Biot number as well as radiation effects whereas results in reduction of Prandtl number. The density of microorganism reduces for greater values of Peclet number.
Biodegradable zinc alloys and Composites for Biomedical Application: an overview of Processing Routes and Possible future work.
(Faculty of Materials Science and Engineering "Gheorghe Asachi” Technical University of Iasi, Romani, 2020-12-23) Kolawole, M. Y, Aweda J. O., Abdulkareem S. and Bello S.A.,
Biodegradable metallic implants are revolutionized alternative materials currently being considered for orthopaedic and stents applications for the restoration and remodeling of defected or fractured hard tissues. Examples of biodegradable metals include magnesium, iron and zinc. Findings had revealed that magnesium and iron show high tendencies of being used as biodegradable metallic implant. However, premature loss of mechanical integrity, high hydrogen gas evolution of magnesium metal as well as slow degradation rate of iron below the clinical benchmark had hindered their applications. On the other hand, Zinc metal with near to ideal degradation rate suitable for orthopaedic application but poor mechanical properties compared to magnesium and iron metals has recently attracted research interest as potential candidate salvager of biodegradable metallic implants. This paper therefore, presents brief review of the current research progress on biodegradable zinc alloys and composites in relation to their processing routes for biomedical application. In addition, key existing and emerging strategies for mechanical properties improvement are highlighted. Processing technique, types and or proportion of alloying elements had been identified as center-hub control for improving mechanical properties of zinc metals. Deductions were made and strategies for further research work on biodegradable zinc alloys were suggested.
Bioenergy technology development in Nigeria – pathway to sustainable energy development
(Int. J. Environment and Sustainable Development, 2019) Sunday O. Oyedepo; Israel S. Dunmade; Tunde Adekeye; Ahme A. Attabo; Olukunle C. Olawole; Philip O. Babalola; Joseph A. Oyebanji
In Nigeria, high and outrageous energy cost constitutes a serious challenge to all aspects of the economy. And this has been a subject of concern in the country over a period of time. A dependable and renewable energy source is of utmost desire to strengthen the nation’s economy and this urgent need cannot be overlooked. As a result of the erratic and expensive power supply to the national grid, it has become ultimately necessary to search for other inexpensive sources of energy to meet the ever increasing energy needs for rural and urban dwellers. In view of the above energy situation in Nigeria, this paper aimed at carrying out a comprehensive review on bioenergy technology option as a pathway to achieving sustainable energy development in the country. The potential, current progressive stages, and prospects of bioenergy conversion techniques, in the Nigeria context, are discussed. The barriers to bioenergy technology development in Nigeria with possible solutions are also presented.
Biphenyl monolayer construction with single transition metal doping as electrocatalysts for conversion CO2 to fuel
(Elsevier, 2024-08-14) Rahadian Zainul; Ali B.M. Ali; Dheyaa J. Jasim; Alaa Dhari Jawad Al- Bayati; Irwanjot Kaur; Abhishek Kumar; Ibrahim Mahariq; Mohd Abul Hasan; Saiful Islam; Kareem, M.W.
Developing sophisticated electrocatalysts is crucial in capturing chemically unreactive CO2 and transforming it into valuable products like fuel. This is essential for effectively tackling the issues of energy crisis and greenhouse gas emissions while maintaining considerable sustainability standards. Nevertheless, effectively managing the selectivity of products while maintaining a small overpotential remains a challenging task. Present work utilized density functional theory (DFT) for studying electrocatalytic potential of various single transition metals (TMs), such as cobalt, iron, and manganese, in process of carbon dioxide reduction reaction (CO2RR). Effectiveness of CO2RR was evaluated for each TM by analyzing their interaction with reaction intermediates (CHO, CO, and COOH) when incorporated into biphenyl monolayer (BPM) systems. Based on the analysis of ΔE values and barriers, it was determined that incorporating Fe into the biphenyl monolayer system is the most efficacious approach for the CO2RR to generate methane. This configuration achieves an exceptionally low overpotential potential (UL) of 􀀀 0.36 V. In hydrogen evolution reaction (HER), it was observed that CO2 exhibits a higher affinity for occupying the activation site on Fe-BPM compared to H2. This difference in adsorption energy (Ead) (􀀀 0.94 eV for CO2 vs. 􀀀 0.43 eV for H2) highlights their distinct behaviors. Additionally, Fe-BPM effectively suppresses the HER during the CO2RR process, as indicated by the HER’s UL of 􀀀 0.43 V. Findings of present study are anticipated to provide a novel direction in the advancement of electrocatalysts with low potential, while simultaneously exhibiting remarkable selectivity and activity for CO2RR.
Characteristics of Al-Alloy/Seashell (SESB) Composites in Acidic and Alkaline Environments
(Covenant Journal of Engineering Technology, 2020-06-28) [3] Abdulkareem, S., Aweda, J. O., Kolawole, M. Y., Ibitoye, S. E., Akintunde, T. S., & Mohammed, M. O.
The corrosion behaviour of Al-alloy/Seashell (SeSh) composites in the acidic and alkaline environment was investigated in this study. Fifteen Aluminum alloy composites samples were produced usingstir casting technology by varying the amount of reinforcement (1.5, 3.0, 4.5, 6.0, 7.5 wt%) and particle size (100, 150, 200 μm) of milled SeShin the Aluminium alloy matrix. The corrosion rate was determined using a weight loss technique after 18 days of immersion at an interval of 72 hours. It was observed that 6.0 wt% of the 100 μm reinforced Aluminium alloy had the best corrosion resistance in acidic and alkaline environments. In general, the reinforced Al-alloy had better corrosion resistance when compared with the unreinforced samples. Analyses of the results show that aluminum alloy seashell composites exhibited better resistance to corrosion in the alkaline environment than the acidic environment
Combustion characteristics of Torrefied corncob and African birch wood residues at higher heating rate
(2025) H.A. Ajimotokan; N.S. Saidu; M.A. Aladodo; K.O. Oladosu; O.D. Samuel; K.O. Abdulrahman; A. El-Suleiman; Y.S. Salihu; K.R. Ajao
The torrefaction of biomass generated from by-products of post-harvest agricultural activities such as corncob or woody residues from saw milling, pruning, and furniture production such as African birch wood, are renewable energy sources whose pyrolytic and combustion properties are crucial during process heating in various applications. This study investigated the combustion characteristics of corncob and African birch wood residues at a higher heating rate and their comparative energy qualities. Samples of corncob and African birch wood residues were collected, sorted, pulverised into particles, and torrefied independently. The raw and torrefied corncob and African birch wood particles were screened into 0.3, 0.5, and 1.0 mm sizes, and their thermogravimetric, proximate, ultimate, heating values, and energy quality analyses were carried out. The torrefied biomass showed better pyrolytic and combustion characteristics relative to the raw samples. However, African birch wood residues appear to be better than corncob residues. The higher heating values (HHVs) ranged from 21.46 to 21.63 MJ/kg and 23.1 to 25.6 MJ/kg for the torrefied samples of corncob and African birch wood residues, respectively. The torrefied sample of African birch wood residues exhibited the highest HHV (25.6 MJ/kg), which compared favourably with the value from a low-rank coal, such as lignite or brown coal. Torrefied African birch wood residues, with their high HHV, can be densified to replace low-rank coal and firewood in a variety of applications.
Combustion characteristics of Torrefied corncob and African birch wood residues at higher heating rate
(2024-12-01) H.A. Ajimotokan; N.S. Saidu; M.A. Aladodo; K.O. Oladosu; O.D. Samuel; K.O. Abdulrahman; A. El-Suleiman; Y.S. Salihu; K.R. Ajao
Comparative study of single pass collector and double pass solar collector filled with porous media
(Asian Journal of Scientific Research, 2013-01-15) Kareem, M.W.
This research reports a comparative study of the convectional single pass flat plate collector and the double pass solar collector filled with porous media such as gravel and metal chips at the lower channel of the absorbing unit. The component materials, design, performance efficiencies, capabilities and the application of the solar collectors are presented to show various disparities that exist between the collectors. Emphasis was laid on the multi-pass approach as a gate way to future development on solar collectors.
Compressive deformation and failure of trabecular structures in a turtle shell.
(Elsevier, 2019-10-01T00:00:00Z) Ampaw, Edward; Owoseni, Tunji Adetayo; Du, Fen; Pinilla, Nelson; Obayemi, John; Hu, Jingjie; Nigay, Pierre-Marie; Nzihou, Ange; Uzonwanne, Vanessa; Zebaze-Kana, Martiale Gaetan; Dewoolkar, Mandar; Tan, Ting; Soboyejo, Winston
Turtle shells comprising of cortical and trabecular bones exhibit intriguing mechanical properties. In this work, compression tests were performed using specimens made from the carapace of Kinixys erosa turtle. A combination of imaging techniques and mechanical testing were employed to examine the responses of hierarchical microstructures of turtle shell under compression. Finite element models produced from microCT-scanned microstructures and analytical foam structure models were then used to elucidate local responses of trabecular bones deformed under compression. The results reveal the contributions from micro-strut bending and stress concentrations to the fractural mechanisms of trabecular bone structures. The porous structures of turtle shells could be an excellent prototype for the bioinspired design of deformation-resistant structures. STATEMENT OF SIGNIFICANCE: In this study, a combination of analytical, computational models and experiments is used to study the underlying mechanisms that contribute to the compressive deformation of a Kinixys erosa turtle shell between the nano-, micro- and macro-scales. The proposed work shows that the turtle shell structures can be analyzed as sandwich structures that have the capacity to concentrate deformation and stresses within the trabecular bones, which enables significant energy absorption during compressive deformation. Then, the trends in the deformation characteristics and the strengths of the trabecular bone segments are well predicted by the four-strut model, which captures the effects of variations in strut length, thickness and orientation that are related to microstructural uncertainties of the turtle shells. The above results also suggest that the model may be used to guide the bioinspired design of sandwich porous structures that mimic the properties of the cortical and trabecular bone segments of turtle shells under a range of loading conditions.
Computer Aided Design and Drafting of Helical Gears
(2012) Akinnuli B. O; Ogedengbe T. I; Oladosu K. O
An interactive user friendly low cost software called “CADDgear” was developed in this study to facilitate the design and drafting of helical and spur gears thereby generating reliable data for use in manufacturing process. The software was developed, using JAVA programming language, as a tool for determining the design parameters and producing accurate and efficient 3D (three dimensional) and 2D (two dimensional) detail working drawings of helical gears. The study considered the existing approaches in use for the design of helical gears and then established a design analysis procedure for helical gear design. The established procedure was implemented through the developed software so that a substantial saving in term of time and cost of production of the design is obtained. The outcome of this research would enhance the designer’s productivity by reducing the time required to synthesis, analyze and document helical gear design. This would permit a thorough analysis of a large number of design alternatives. Results generated by the software shows very good agreement with that obtained through manual calculation using the established procedure. It was observed that the developed software successfully increase productivity over manual gear design and drafting by approximately thirty-four times in term of the time required for the design

Browse

Browsing Department of Mechanical Engineering by Title

Results Per Page

Sort Options