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Dynamic viscosity converter




Poiseuille (Pa·s)


Poise (dyne·s/cm2 = g/cm·s)








Calculate with this converting program the units to US/UK units or SI units.

You can see viscosity as the resistance. When the resistance gets higher, the viscosity get greater with it. The unit of dynamic viscosity is the Poiseuille (=Pa·s). When you know the viscosity, you can amongst others calculate the number of Reynolds. With that you know whether the stream is turbulent or not. A turbulent stream is a stream where the velocity of the particles have random directions. When the stream is not turbulent (laminar), the velocity and direction of the particles is always the same. If you know the number of Reynolds, you can calculate the pressure in a pipe line.

Calculation of Reynolds:

Re = r. v.D/h.

r = density (kg/m3) =
v = speed (m/s) =
D = diameter (m) =
h = dynamic viscosity (Pa·s) =

The Reynolds number is: This is

Now you can calculate the pressure. You need to know the length (in meters) of the pipe. This is m. You also need the friction e:.

The pressure is about: Pa. This is with a pipe that is straight.

Lenntech BV is not responsible for programming or calculation errors on this sheet. Feel free to contact us for any feedback.

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