Q1: Peclet number (Pe) is given by

ANS:A - Pe = Re.Pr

The Peclet number (Pe) is given by: PrNuPe=NuRe⋅Pr​ Explanation:

• The Peclet number (Pe) is a dimensionless quantity that characterizes the relative importance of convective heat transfer to conductive heat transfer in a fluid flow.
• It is defined as the ratio of the rate of convection to the rate of thermal diffusion.
• The Peclet number is calculated using the Reynolds number (Re), the Prandtl number (Pr), and the Nusselt number (Nu).
• Re represents the ratio of inertial forces to viscous forces and characterizes the flow regime.
• Pr represents the ratio of momentum diffusivity (kinematic viscosity) to thermal diffusivity and characterizes the relative importance of momentum and thermal diffusivities.
• Nu represents the Nusselt number, which represents the ratio of convective heat transfer to conductive heat transfer across a fluid boundary layer.