Consider incompressible laminar flow of a constant property Newtonian fluid in an isothermal circular tube. The flow is steady with fully-developed temperature and velocity profiles. The Nusselt number for this flow depends on

Answer :

Solution :

• Nusselt no. for convection with uniform temperature circular tubes.  Nu_D = 3.66
• Convection with uniform heat flux for circular tubes. Nu_D = 4.36
• Dittus-Boelter equation is an explicit function for calculating the nusselt number for rough tubes

               Nu_D = 0.023Re_D^4/5 Prⁿ

• Flat plate in laminar flow

      N_ux = 0.332Re_x^1/2Pr^1/3 (Pr > 0.6)