The purpose of the present investigation is to explore the effect of a hybrid nanoparticle on the nanofluidic flow around a heated circular cylinder. The unrestricted flow of Cu-Al2O3/H2O hybrid nanofluid is referred as the working fluid for the Reynolds number range \(20 \le {\text{Re}} \le 40\) . The solid fraction Al2O3 ( \({\varphi }_{1}\) ) and Cu nanoparticle ( \({\varphi }_{2}\) ) vary in the base fluid (H2O) in the range \(0\% \le \varphi \le 7\%\) . Within this range of Reynolds numbers, the base fluid flow remains steady, forming recirculating wakes behind the body. However, with addition of the nanoparticles, the steady flow gradually transforms into unsteady periodic with vortex shedding. We calculate the critical hybrid solid fractions \({\varphi }_{{{\text{cr}}}}\) at which the inherent steady wake transforms into unsteady periodic with vortex shedding. The primary goal of the study is to comprehend the relation that a hybrid nanofluid forms with a nanofluidic flow within a few frames of reference. The hybrid nanofluid exhibits better heat transmission characteristics as compared to nanofluid and provides faster instability while flowing over a bluff body.
