History[edit]
The project was conceived around 1988. At first it was intended to be a companion to a chemical reactor design course. Real development was started by John W. Eaton in 1992. The first alpha release dates back to January 4, 1993 and on February 17, 1994 version 1.0 was released. Version 4.0.0 was released on May 29, 2015.
The program is named after Octave Levenspiel, a former professor of the principal author. Levenspiel is known for his ability to perform quick back-of-the-envelope calculations.[10]