Browsing by Author "Popoola, O.T."

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    Cooling potential of formulated bio-quenchant oils on cast Aluminium alloy material.
    (University of Chemical Technology and Metallurgy (UCTM), Sofia, Bulgaria, 2020) Adekunle, A.S.; Adeleke, A.A.; Gbadamosi, T.A.; Nwosu, F.O.; Odusote, J.K.; Omoniyi, P.O.; Popoola, O.T.; Adebiyi, K.A.
    The biodegradable vegetable oil based quenchants can serve as cooling media alternative to that of the toxic non-biodegradable petroleum based mineral oil in a heat treatment of aluminium and its alloy. 70 vol. % of edible vegetable oil are blended with 30 vol. % of Jatropha oil to form bio-quenchant oils for Aluminium (Al)-alloy probe treated at 500oC and soaked for 15 min in a muffle furnace. The cooling potential properties such as the cooling rate, the heat transfer coefficient, the Grossman quench severity and the biot number are investigated. The results obtained show that the blended bleached (BB) melon oil provides the highest cooling rate of 49.30oC s-1, while the blended raw (BR) palm oil ensures the lowest cooling rate of 18.45oCs-1. Heat transfer coefficients of 704.6 Wm-2K-1, 432.3 Wm-2K-1, and 394.4 Wm-2K-1 are exhibited by the blended bleached melon oil, the blended raw melon oil and the blended bleached groundnut oil, respectively. They are found higher than that of a petroleum based mineral oil, which amounts to 68.7 Wm-2K-1. The lowest heat transfer coefficient of 272.11 Wm-2K-1 is obtained in case of using a blended raw palm oil. The quench severity of the blended bleached melon oil, the blended raw melon oil and the blended raw groundnut oil refers to a Grossman H-factor of 1.01 m-1, 0.78 m-1, and 0.67 m-1, respectively. The latter values are higher than that obtained in case of a blended raw palm oil, which is equal to 0.37 m-1. However, the heat flow parameters obtained reveal that the blended bleached and the blended raw melon and groundnut oil can be characterized as fast quenching oils, while the blended bleached and the blended raw palm oil can be characterized as medium quenching oils of results comparable to and even better than those of the industrial petroleum based mineral oil
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    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.
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    Melting of Aluminium in Pulsed Combustor fired Furnace
    (Nigerian Society of Engineers, 2011) Olorunmaiye, J.A.; Popoola, O.T.; Ibrahim, R.