Table 1.
Breathing | Speaking | |
Peak flow rates | 0.7 L/s (22) | L/s |
Or velocities | 0.5 m/s (23) | (22, 24–28) |
Peak Reynolds numbers | to | to |
We assume a typical length scale for the orifice or mouth of diameter for calculating the Reynolds numbers, , where is the average speed at the mouth or orifice exit and the kinematic viscosity of air m2/s.