Béla Karlovitz

Béla Karlovitz (November 9, 1904 – February 29, 2004) was a Hungarian engineer who pioneered research into the generation of electricity directly from a body of hot moving gas without any mechanical moving parts. This process is known as magnetohydrodynamic generation or MHD generation for short.

He received his M.E. degree from Technical University, Budapest, Hungary and his E.E. degree from the Federal Institute of Technology, Zurich, Switzerland. Besides his publications in MHD, he is the author of many publications on turbulent flames and combustion instabilities. He was the head of the Flame Research Section, Explosives and Physical Science Division, Bureau of Mines, Pittsburgh, PA. Subsequently, he was with Combustion and Explosive Research, Inc. in Pittsburgh, PA. In combustion, Karlovitz is known as the first to introduce the concept of flame stretch. The Karlovitz number is named after him. It is a non-dimensional quantity defined as: ${\displaystyle {\mathit {Ka}}=kt_{c}}$ where ${\displaystyle t_{c}}$ is the characteristic flow time (s) and ${\displaystyle k}$ is the flame stretch rate (1/s): ${\displaystyle k=(dA/dt)/A}$; where ${\displaystyle A}$ is the unit area of the flame and consists of the points that stay on the flame surface.