<human>:  What is the Reynolds number?
<bot>: The Reynolds number is a measure of the ratio of the fluid’s viscous and inertial velocities. A Reynolds number of 1,000 means that the fluid’s velocity is 1000 times greater than the fluid’s velocity due to its viscosity. In a turbulent flow, the fluid’s velocity is high, and the fluid’s viscosity is low, which means the Reynolds number is very large.