Browsing by Author "Adegun, I.K."

Now showing 1 - 7 of 7
  • Item
    A 3D Finite Element Analysis of Incompressible Fluid Flow and Contaminant Transport through a Porous Landfill
    (Faculty of Engineering, Taylors University, Malaysia, 2014) Adegun, I.K.; Komolafe, D.O.; Ahmed, Kadhim Hussein; OYEKALE, J.O.
    The paper investigated the flow of incompressible fluid and contaminant transport through a Porous Landfill using a numerical technique. A threedimensional finite element analysis technique was adopted for the solution. The problem was based on the Darcy’s Law and the Advection-Dispersion equation. The solutions of the Darcy’s and Advection-Dispersion equations were generated using Finite Element Analysis Software known as COMSOL Multiphysics. This simulation tool tracked the contaminant transport in the Landfill for 360 days at 10 days interval. It first modeled steady-state fluid flow by employing the Darcy’s Law Application Mode and then followed up with a transient solute-transport simulation by employing the Solute-Transport Application Mode from the Earth Science Module of COMSOL. The solution results obtained from this model were found to be in close agreement with reallife data obtained at the 130- million ton Bukit Tagar Mega Sanitary Landfill site, Selangor near Kuala Lumpur, Malaysia. This showed that the model can effectively predict the trends in the distributions of pollutants from a Municipal Solid Waste Landfill into nearby land and water sources. The model is thus applicable to the issues of environmental protection and safety of groundwater.
  • Item
    Effects of Eccentricity of the Ellipse and Type of Fluid flowing on Heat Transfer in Elliptic Pipes
    (Faculty of Engineering, University of Lagos., 2013) Adegun, I.K.; Okoshone, J.O.; Popoola, O. T.
    The paper presents laminar forced convection of pseudo-plastic, Newtonian and dilatants fluids inside elliptic tubes with the intention of eliciting the effects of eccentricity of the geometry and the applicable heat exchanging fluids on flow pattern and heat transfer by the configuration. Power-Law for non-Newtonian fluids in conjunction with continuity, momentum and energy transport equations were adopted for the solution. A thermal boundary condition of uniform wall temperature was considered for the analysis. A computational algorithm was developed from the governing equations using a Finite Difference Method (FDM). A program was written in Quick Basic to generate the results for the influence of the variables considered to be of interest. The results obtained show that pseudo-plastic fluids flowing in elliptic duct transfer more heat and appear to be a better heat exchanging fluid than other fluids. For fluids with flow behavior index n=1/3 , n=1 and n = 3, the mean Nusselt numbers are respectively 4.1734, 3.6906 and 3.2168. These results agree closely with the values obtained by Cotta and Ozisik [Nu =4.1753 for n=1/3 and Nu= 3.4090 for n=3]. It was noted that an eccentricity range of 0.866
  • Item
    Effects of mixing ratios of cow dung, cassava peel and rice husk on the thermodynamic properties and composition of biogas in anaerobic digester
    (Advances in Multidisciplinary & Scientific Research Journal, 2016) Olorunmaiye, J.A.; Adegun, I.K.; Ogunniyi, O.J.; Aweda, J.O.; Ajiboye, T.K.; Abdulkareem, S.
  • Item
    INFLUENCE OF SOME VARIABLE PARAMETERS ON HORIZONTAL ELLIPTIC MICRO-CHANNELS WITH INTERNAL LONGITUDINAL FINS
    (Faculty of Engineering, University of Nigeria, Nsukka, 2013) Adegun, I.K.; Jolayemi, T.S.; Olayemi, O.O.; Popoola, O.T.
    he study investigates the laminar flow and heat transfer characteristics in elliptic microchannels of varying axis ratios and with internal longitudinal fins, operating in a region that is hydrodynamically and thermally fully developed; purposely to determine the effects of some salient fluid and geometry parameters such as Reynolds number, Prandtl number, aspect ratio ( and fin heights on flow pattern and rate of heat transfer. Numerical method using the finite difference technique was adopted for the solution. A code in Quick Basic was developed to generate the results. Results show that fin height of H=0.6 provided the optimum heat transfer enhancement for the configuration of e = 0, e= 0.433 and e=0.714; for e=0.866, fin height of H= 0.4 is tolerable. Result also show that Nusselt number increases with Reynolds number for all axis ratios investigated. However, at Re=200 a slight trough was observed in Nusselt number Versus Reynolds number relationship indicating a critical flow condition. It was also established that at Pr >5, Nusselt number and bulk fluid temperature, are independent of fluid properties.
  • Item
    Numerical Simulation of Forced Convective Heat Transfer in Inclined Elliptic Ducts with Multiple Internal Longitudinal Fins
    (Elsevier, 2018) Adegun, I.K.; Jolayemi, T.S.; Olayemi, O.A.; Adebisi, A.M.
    The paper presents numerical study of forced convective heat transfer in internally finned elliptic geometry to determine the effect of parameters such as Reynolds number, Prandtl number, aspect ratio, fin heights, number of fins and orientations of the duct on the heat transfer coefficient, temperature history and velocity profiles. The walls were assumed to be subjected to a thermal boundary condition of constant heat flux and the effect of slip boundary is assumed negligible. Finite difference technique was adopted for the solution and results were generated using a code written in Qb-64. The study indicated that number of fins (F ¼ 8) provided the optimum heat transfer augmentation. For all the geometries investigated, Nusselt number, average velocity and bulk fluid temperature were enhanced by the inclinations in the range 0 6 h 6 75 . For a flow regime of 50 6 Re 6 200, the effect of inclination on heat transfer is negligible, but it worth noting the existence of a critical Reynolds number, Re ¼ 200, above which the effect of inclination on fluid flow becomes noticeable. Also, at Pr P 5, Nusselt number and bulk fluid temperature were independent of fluid properties. The results obtained could be applied in the prediction of parameters for the design of compact heat exchangers for industrial applications
  • Item
    Numerical Analysis of the Effect of Selected Geometrical Parameters and Fluid Properties on MHD Natural Convection Flow in an Inclined Elliptic Porus Enclosure with Localized Heating
    (Willey Periodicals, 2017) Adekeye, T; Adegun, I.K.; Okekunle, P.O.; Hussein, A.K.; Oyedepo, S.O.; Adetiba, E; Fayomi, O.S.I
    Magnetohydrodynamic (MHD) natural convection flow and associated heat convection in an oriented elliptic enclosure has been investigated with numerical simulations. A magnetic field was applied to the cylindrical wall of the configuration, the top and bottom walls of the enclosure were circumferentially cooled and heated, respectively, while the extreme ends along the cross-section of the elliptic duct were considered adiabatic. The full governing equations in terms of continuity, momentum, and energy transport were transformed into nondimensional form and solved numerically using finite difference method adopting Gauss–Seidel iteration technique. The selected geometrical parameters and flow properties considered for the study were eccentricity (0, 0.2, 0.4, 0.6, and 0.8), angle of inclination (0°, 30°, 60°, and 90°), Hartmann number (0, 25, and 50), Grashof number (104, 105, and 106), and Darcy number (10−3, 10−4, and 10−5). The Prandtl number was held constant at 0.7. Numerical results were presented by velocity distributions as well as heat transfer characteristics in terms of local and average Nusselt numbers (i.e., rate of heat transfer). The optimum heat transfer rate was attained at e value of 0.8. Also, the heat transfer rate increased significantly between the angles of inclination 58° and 90°. In addition, Hartmann number increased with decreased heat transfer rate and flow circulation. A strong flow circulation (in terms of velocity distribution) was observed with increased Grashof and Darcy numbers. The combination of the geometric and fluid properties therefore can be used to regulate the circulation and heat transfer characteristics of the flow in the enclosure.
  • Item
    Parametric study of natural convection heat transfer from an inclined rectangular cylinder embedded in a square enclosure
    (Taylor & Francis, 2021) Olayemi, O.A.; Khaled, Al-Farhany; Temitope, O.J.; Victor, O.O.; Odetunde, C.B.; Adegun, I.K.
    This paper presents the effects of aspect ratio (0.1 < AR < 0.7), Rayleigh number (102 < Ra < 106) and inclination angle (0o< γ <90o) of the heated rectangular cylinder on heat transfer and fluid flow characteristics due to natural convection in air around heated rectangular cylinders of different sizes inside a cold square enclosure. Galerkin finite element method was adopted for the solution of the developed model. The walls of the enclosure were maintained at an isothermal cold temperature while the boundaries of the rectangular cylinder were kept at a constant hot temperature. The results are presented in the form of isothermal contours, stream functions, local and average Nusselt numbers. It has been found that for the range of aspect ratio and Rayleigh number considered, the rate of heat transfer increases with increasing aspect ratio and Rayleigh number. Furthermore, the orientation angle of the rectangular cylinder was found to generally augment heat transfer rate except at AR value of 0:1, where the average Nusselt number declines beyond γ = 45o for all the range of Rayleigh numbers considered. Results from the present study could be applied to nuclear reactor technology and cooling of electronic chips system optimisation.