Choose the right answer 1. The mean Nusselt number for fully developed laminar flow in a circular tube under a constant heat flux a. depends on Reynolds number b. depends on Prandtl number c. is constant 2. The Prandtl number for a flowing fluid greater than unity indicates that the hydrodynamic boundary layer thickness is a. less than the thermal boundary layer thickness b. equal to the thermal boundary layer thickness c. greater than the thermal boundary layer thickness 3. In natural convection heat transfer, the Nusselt number is a function of a. Re and Pr b. Re and Gr c. Gr and Pr 4. A fluid is flowing coefficient along the length a. decreases long a plate ng a uniform heat flux. The local transfer b. remain constant c. increases 5. For fully developed laminar flow and heat transfer in a heated long circular tube, if the flow velocity is doubled and the tube diameter is halved, the heat transfer coefficient will be b. half of the original value a. four times of the original value before c. same as d. double of the original value

Choose the right answer 1. The mean Nusselt number for fully developed laminar flow in a circular tube under a constant heat flux a. depends on Reynolds number b. depends on Prandtl number c. is constant 2. The Prandtl number for a flowing fluid greater than unity indicates that the hydrodynamic boundary layer thickness is a. less than the thermal boundary layer thickness b. equal to the thermal boundary layer thickness c. greater than the thermal boundary layer thickness 3. In natural convection heat transfer, the Nusselt number is a function of a. Re and Pr b. Re and Gr c. Gr and Pr 4. A fluid is flowing coefficient along the length a. decreases long a plate ng a uniform heat flux. The local transfer b. remain constant c. increases 5. For fully developed laminar flow and heat transfer in a heated long circular tube, if the flow velocity is doubled and the tube diameter is halved, the heat transfer coefficient will be b. half of the original value a. four times of the original value before c. same as d. double of the original value

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.16P

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Choose the right answer 1. The mean Nusselt number for fully developed laminar flow in a circular tube under a constant heat flux a. depends on Reynolds number b. depends on Prandtl number c. is constant 2. The value of Prandtl number for air is about а. О.1 b. 0.3 с. 0.7 3. In natural convection heat transfer, the Nusselt number is a function of a. Re and Pr b. Re and Gr c. Grand Pr 4. A fluid is flowing along a plate having a high uniform wall temperature. The heat transfer along the length a. decreases b. remain constant c. increases 5. For fully developed laminar flow and heat transfer in a heated long circular tube, if the flow velocity is doubled and the tube diameter is halved, the heat transfer coefficient will be a. four times of the original value before b. half of the original value с. same as d. double of the original value
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