A) Among the nondimensional numbers, in free convection, average Nusselt number depends on only Grashof and Prandtl numbers. only Grashof number. Rayleigh number. Reynolds number. B) For ideal gases, the specific heat capacity at constant pressure, thermal conductivity, dynamic viscosity, and Prandtl number are independent of pressure. How will the ratio of thicknesses of velocity boundary layer and thermal boundary layer change if pressure is increased from 1 atm to 5 atm for the flow of an ideal gas over a flat plate? We need to know the actual fluid properties to tell It will remain the same. It will decrease by a factor of 5. It will increase by a factor of 5.

A) Among the nondimensional numbers, in free convection, average Nusselt number depends on only Grashof and Prandtl numbers. only Grashof number. Rayleigh number. Reynolds number. B) For ideal gases, the specific heat capacity at constant pressure, thermal conductivity, dynamic viscosity, and Prandtl number are independent of pressure. How will the ratio of thicknesses of velocity boundary layer and thermal boundary layer change if pressure is increased from 1 atm to 5 atm for the flow of an ideal gas over a flat plate? We need to know the actual fluid properties to tell It will remain the same. It will decrease by a factor of 5. It will increase by a factor of 5.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.13P

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