# Viscosity of a Mixture

Written by Jerry Ratzlaff on . Posted in Fluid Dynamics

This calculates the effective viscosity of gasses.

## formula

$$\mu = \frac {\sum ({\mu_i y_i \sqrt{M_i}})} {\sum ({y_i \sqrt{M_i}})}$$

Where:

$$\mu$$ (Greek symbol mu) = dynamic viscosity of the gas mixture

$$\mu_i$$ (Greek symbol mu) = dynamic viscosity of a gas component

$$y_i$$ = mole fraction or percent of gas component

$$M_i$$ = molecular weight of gas component