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This calculator computes the Reynolds Number given the flow characteristics asked for below. It outputs the flow type you can expect (laminar, transitional, or turbulent) based on the Reynolds Number result.

Think of the Characteristic Distance as the distance from the leading edge (where the fluid first makes contact) for flow over a plate, or as the pipe diameter for flow inside a pipe.

  Free-stream fluid velocity, V:    
  Characteristic distance (or pipe diameter), D:    
  Fluid density, r:    
  Fluid viscosity (dynamic), m:    
  Reynolds Number, R:  1.00 × 105  
Plate flow is transitioning to turbulent at a distance D from the leading edge.
Pipe flow is fully turbulent in a pipe of diameter D.
Equation Behind the Calculator
The Reynolds Number is found from the equation,