# Courant Number

on . Posted in Dimensionless Numbers

Courant number, abbreviated as Co, a dimensionless number, is the measure of how much information traverses a computational grid cell in a given time interval.

## Courant Number formula

$$\large{ Co = \frac{ \Delta t \; U}{ \Delta x } }$$
Symbol English Metric
$$\large{ Co }$$ = Courant number $$\large{dimensionless}$$
$$\large{ U }$$ = magnitude of the velocity (whose dimension is length/time) $$\large{\frac{ft}{sec}}$$ $$\large{\frac{m}{s}}$$
$$\large{ \Delta x }$$ = distance between any two consecative points $$\large{ ft }$$ $$\large{ m}$$
$$\large{ \Delta t }$$ = time interval $$\large{ sec}$$ $$\large{ s}$$