Understanding the Relationship between Turbulence and the Reynold Number

AI Thread Summary
The discussion centers on the relationship between turbulence and the Reynolds number, specifically addressing why complete turbulence is considered independent of the Reynolds number. It is clarified that in the fully turbulent flow region, as indicated on the Moody diagram, the friction factor remains constant regardless of changes in the Reynolds number. Instead, the friction factor is influenced solely by the relative roughness of the pipe. Participants express confusion over this concept, seeking further explanation of the phenomenon. Understanding this relationship is crucial for accurately analyzing fluid flow in engineering applications.
werson tan
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Homework Statement


why the author gave that the complete turbulenece is indpendent on the Reynold number ?

Homework Equations

The Attempt at a Solution


For the turbulence to occur , the Reynold number must be higher than certain value , am i right . So , IMO , turbulenet is dependent on the Reynold number
 

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werson tan said:

Homework Statement


why the author gave that the complete turbulenece is indpendent on the Reynold number ?

Homework Equations

The Attempt at a Solution


For the turbulence to occur , the Reynold number must be higher than certain value , am i right . So , IMO , turbulenet is dependent on the Reynold number
You're not correctly comprehending what this slide is saying.

First, it's discussing the friction factor f as it's plotted on the Moody diagram:

6837190_f520.jpg

​

In the zone where the flow is completely turbulent, i.e. to the right of the dashed line, the friction factor is constant w.r.t. the Reynolds number. In this region, the friction factor f depends on the relative pipe roughness only.
 
SteamKing said:
You're not correctly comprehending what this slide is saying.

First, it's discussing the friction factor f as it's plotted on the Moody diagram:

6837190_f520.jpg

​

In the zone where the flow is completely turbulent, i.e. to the right of the dashed line, the friction factor is constant w.r.t. the Reynolds number. In this region, the friction factor f depends on the relative pipe roughness only.

SteamKing said:
You're not correctly comprehending what this slide is saying.

First, it's discussing the friction factor f as it's plotted on the Moody diagram:

6837190_f520.jpg

​

In the zone where the flow is completely turbulent, i.e. to the right of the dashed line, the friction factor is constant w.r.t. the Reynolds number. In this region, the friction factor f depends on the relative pipe roughness only.
Can you explain this phenomenon?
 
werson tan said:
Can you explain this phenomenon?
You can read a more detailed explanation here:

https://www.uio.no/studier/emner/matnat/math/MEK4450/h11/undervisningsmateriale/modul-5/Pipeflow_intro.pdf
 
SteamKing said:
You can read a more detailed explanation here:

https://www.uio.no/studier/emner/matnat/math/MEK4450/h11/undervisningsmateriale/modul-5/Pipeflow_intro.pdf
this is the book that i use . can you expalin why during the complete turbulent , it is independent of reynold number ?
 

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