COMPLETE GUIDE FOR DRILLING MUDS FLOW REGIMES & RHEOLOGY MODELS
Chaper I
Drilling Mud Flow Regimes
Flow Regimes are the behavior of the fluid while flowing in a well. The most common regimes are laminar, turbulent, and transitional. Unfortunately, it is impossible to clearly define each type in the well. As an example, mud flow may be predominantly laminar, although the flow near the pipe waIls during pipe rotation may be turbulent.
1) Laminar Flow. 
The most common annular flow regime is laminar.
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