Horizontal circular cylinder Boundary layer 1 Boundary layers 1 Brinkman fluid 1 Circular cylinders 1 Convective transport 1 Flow of fluids 1 Free convection 1 Friction 1 Fundamental mechanisms 1 Heat transfer analysis 1 Heat transfer coefficients 1 Horizontal circular cylinders 1 Jeffrey nanofluid 1 Mixed convection 1 Mixed convection flow 1 Numerical solution 1 Similarity transformation 1 Skin friction 1 Temperature profiles 1 Transport properties 1 Visco-elastic parameters 1 Viscoelastic fluid 1 Viscoelasticity 1 Viscous dissipation 1