For cross flow over a long cylinder, what is the appropriate length parameter to beused in Reynolds or Nusselt number?Length.Diameter.Radius. The critical Reynolds number for external flow (which started as a laminar flow) overthin flat plate is|1700500,0002300Depends on fluid properties.

For cross flow over a long cylinder, diameter is the appropriate length parameter to be used in…

Answered: The critical Reynolds number for…

The critical Reynolds number for external flow (which started as a laminar flow) over thin flat plate is |1700 500,000 2300 Depends on fluid properties.

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.35P

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Concept explainers

Properties of Fluids

The term fluid represents a type of substance that can easily change its shape under any external pressure/force and can flow. Fluids can acquire any shape in which it is stored and can resist normal stresses but cannot resist shear stress in rest condition. Whenever external shear stress is applied to fluids, it starts to flow. The fluids may be liquid or gas. Example- water, air, etc.

Question

For cross flow over a long cylinder, what is the appropriate length parameter to be
used in Reynolds or Nusselt number?
Length.
Diameter.
Radius.

The critical Reynolds number for external flow (which started as a laminar flow) over
thin flat plate is
|1700
500,000
2300
Depends on fluid properties.

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