Unsteady axisymmetric radiative Cu-Al2O3/H2O flow over a radially stretching/shrinking surface

• Main Authors: Khashi’ie, Najiyah Safwa, Md Arifin, Norihan, Pop, Ioan
• Format: Article
• Published: Elsevier B.V. 2022
• Online Access: http://psasir.upm.edu.my/id/eprint/102544/; https://www.sciencedirect.com/science/article/pii/S0577907322001551

The unsteady stagnation point flow of hybrid nanofluid past an impermeable disk is investigated with the presence of thermal radiation. The pair of aluminium oxide and copper with 2% of φhnf are numerically analyzed using the existing correlations of hybrid nanofluid. The governing model is simplified into a set of differential (similarity) equations and then, numerically solved by employing the bvp4c solver in the Matlab software. The dual solutions are presented while the stability analysis certifies the physical/real solution. The availability of dual solutions is detected when the range of control parameters are 1.5 ≤ B ≤ 1 (unsteadiness decelerating parameter), 0 ≤ R ≤ 0.1 (radiation parameter) and λc ≤ λ ≤ 0.5 (velocity ratio parameter). The accession of radiation parameter and the use of different nanofluids (Cu-H2O, Al2O3-H2O and Cu-Al2O3/H2O) are not prolonging the boundary layer separation. However, the addition of R, B and the use of Cu-Al2O3/H2O hybrid nanofluid enhance the thermal performance of the working fluid.