Prandtl numbers are named after a pioneer in what applied science?
Prandtl number The Prandtl number (Pr) or Prandtl group is a dimensionless number, named after the German physicist Ludwig Prandtl, defined as the ratio of momentum diffusivity to thermal diffusivity. That is, the Prandtl number is given as:
Nikolay Umov Nikolay Alekseevich Umov (Russian: Никола́й Алексе́евич У́мов ; January 23, 1846 – January 15, 1915) was a Russian physicist and mathematician known for discovering the concept of Umov-Poynting vector and Umov effect.