AbstractUnsteady natural convection heat transfer of nanofluid within cavities with local heaters occurs in several engineering applications. Therefore, investigation of nanofluid flow and heat transfer processes in such systems has a considerable value for evolution of industry. In the current investigation, unsteady MHD natural convection flow of Cu-water nanofluid and heat transfer behavior in square cavity containing a centered adiabatic square block. The mathematical formulation part for present problem is presented in succeeding section. It has been found the size of the adiabatic obstacle influences the behavior of the nanofluid and conduction becomes dominant when size aspect ratio increases to 0.5. It is also noticed that angle of the applied magnetic field can maximize(minimum)the rate of heat transfer if applied in the stream-wise (normal) direction. The novelty of the present work is to consider cavity containing a centered adiabatic square block as well as unsteady effects in the natural convection of nanofluids.
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