1. The thermal boundary layer will be thicker than the velocity boundary layer if Pr>1. 2. For laminar flow in a tube subjected to a uniform heat flux, the fluid temperature decreases linearly along the tube. 3. Gravity force rather than buoyancy force plays a more important role in free convection. 4. Reynolds number is the ratio of the buoyancy force and viscous force. 5. The hydraulic diameter of annulus is D2-D1.

1. The thermal boundary layer will be thicker than the velocity boundary layer if Pr>1. 2. For laminar flow in a tube subjected to a uniform heat flux, the fluid temperature decreases linearly along the tube. 3. Gravity force rather than buoyancy force plays a more important role in free convection. 4. Reynolds number is the ratio of the buoyancy force and viscous force. 5. The hydraulic diameter of annulus is D2-D1.

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.2DP

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