Effects of Second-Order Slip Flow and Variable Viscosity on Natural Convection Flow of <math xmlns="http://www.w3.org/1998/Math/MathML" id="M1"> <mfenced open="(" close=")" separators="|"> <mrow> <msub> <mrow> <mtext>CNTs</mtext> <mo>−</mo> <mtext>Fe</mtext> </mrow> <mrow> <mn>3</mn> </mrow> </msub> <msub> <mrow> <mtext>O</mtext> </mrow> <mrow> <mn>4</mn> </mrow> </msub> </mrow> </mfenced> </math>/Water Hybrid Nanofluids due to Stretching Surface

This study deals with natural convection unsteady flow of CNTs − Fe 3 O 4 /water hybrid nanofluids due to stretching surface embedded in a porous medium. Both nanoparticles id="M3"> SWCNTs and id="M4"> MWCNTs are used water as base fluid. Effects volume friction, second-order velocity slip condition, temperature-dependent viscosity investigated. The governing problem is solved numerically employing spectral quasilinearization method (SQLM). results presented discussed via parameters using graphs tables. disclose that the thermal conductivity id="M5"> / H 2 higher than id="M6"> value nanoparticle fraction. Also, show momentum boundary layer reduces while gros values parameters. skin friction coefficient improves, local heat transfer rate decreases fraction, viscosity, Furthermore, more coefficients lower reported id="M7"> nanofluid id="M8"> nanofluid. Thus, obtained promising for application nanotechnology biomedicine sectors.