Møtran (signifying "multi-phase transient") is a package of software for simulating flows in two-phase (gas/liquid) fluid systems like networks of such components as pipes, T junctions, pumps, evaporators, and condensers. The software is based on a two-fluid formulation that can accommodate unequal velocities and temperatures for the two phases. Møtran provides for single-phase, bubbly, slug, stratified, and annular flow regimes. Mechanistic models are used for establishing the boundaries between flow regimes and for constitutive relations that represent wall shear, interfacial shear, wall heat transfer, interfacial heat transfer, and phase change. Constitutive models are provided for each of the flow regimes, and all are selected and calculated dynamically during solution for each grid point in the network. The software is applicable at all levels of gravitation, whether steady or time varying. Møtran includes a state-of-the-art graphical user interface (GUI) and an integrated fluid-property database. The user assembles the representation of the fluid system (which can be of arbitrary topology) through drag-and-drop operations on the GUI. The software predicts pressures, volume fractions, temperatures, and velocities of the phases throughout the system.

This program was developed under the direction of James J. Barry and Christopher J. Crowley of Creare Inc. for Glenn Research Center. For further information, please contact James J. Barry at (603) 643-3800.

Inquiries concerning rights for the commercial use of this invention should be addressed to

NASA Glenn Research Center
Commercial Technology Office
Attn: Steve Fedor
Mail Stop 4–8
21000 Brookpark Road
Ohio 44135.

Refer to LEW-16937.