ECLIPSE (reservoir simulator)

ECLIPSE is an oil and gas reservoir simulator originally developed by ECL (Exploration Consultants Limited) and currently owned, developed, marketed and maintained by SIS (formerly known as GeoQuest), a division of Schlumberger.

ECLIPSE uses finite differences to solve material and energy balance equations modelling a subsurface petroleum reservoir. ECLIPSE 100 (a version of ECLIPSE) solves the Black oil equations (a fluid model).