Research

Natural convection under the presence of external magnetic field in a square cavity with a square annulus at the center filled with Al2O3- water nanofluid is the topic of interest in this investigation. We showed that the magnetic field has an negative effect on the strength of the flow field. The effect of change in Ra and Ha on streamlines, isotherms and Nusselt number (Na) has been investigated. Effect of solid volume fraction on Na has also been analyzed.

Publication: R. H. Kabir et al., International Conference on Mechanical Engineering and Renewable Energy 2015 (ICMERE2015), CUET, Chittagong, Bangladesh

Mixed convection analysis using non-Newtonian ferrofluid in lid-driven cavity with rotating cylinder at the center has been analyzed. Dilatant fluid (n > 1) shows more strong flow and thermal field at higher rotational speed of cylinder. Power law index, rotational speed, Richardson number and solid volume fraction has a significant impact on velocity profile. More than 46% better heat transfer has been recorded at higher rotational speed (Ω = 15) in case of dilatant ferrofluid. Non-Newtonian ferrofluid exhibits better heat transfer (more than 15%) than non-Newtonian fluid. Further investigation can be made to develop a critical range of different pertinent parameters in this regard.

Publication: K. M. Rabbi,M. Shuvo, R. H. Kabir et al., AIP Conf. Proc. 1754, 040016 (2016).

• Heat Transfer Enhancement Using Nano-particles

Heat transfer analysis in an diamond shaped cavity has been performed in this study.Carbon nanotube (CNT)-H2O nanofluid has been compared with pure water as working fluid. For Unsteady Natural Convection phenomenon Higher Rayleigh Number and High percentage of Nanoparticles ensured better heat transfer while at lower Rayleigh Numbers the effect of Nanoparticles have no significant impact on the heat transfer compared to the base fluid (pure water).

Authors: M.M. Rahman, Moinuddin Shuvo, Rabiul Hasan Kabir, Khan Md. Rabbi