The complex interfacial phenomena involved in two-phase gas-liquid flow have defied mathematical simplification and modeling. However, the systems are used in heat exchangers, condensers, chemical processing plants, and nuclear reactor systems. The present work considers a 1 mm square minichannel and adiabatic flows corresponding to practical PEM fuel cell conditions. Pressure drop data is collected in experimentation covering mass fluxes of 4.0-33.6 kg/m2s, which correspond to superficial gas and liquid velocities of 3.4-10 m/s and 0.001-0.02 m/s respectively. The experiments are repeated with water of reduced surface tension, caused by the addition of surfactant, in order to quantify the surface tension effects, as it is recognized that surface tension is an important parameter for two-phase flow in minichannels. The published models are evaluated for correct consideration of the surface tension effects and accurate prediction of pressure drop. The addition of surfactant is shown to have no discemable influence on pressure drop. Two models by Chen et al. are found to acceptably predict the experimental data within 20-25%, however a new model is proposed that matches the experimental data with deviations of less than 5%.

Library of Congress Subject Headings

Two-phase flow; Fluid-structure interaction; Pipe--Hydrodynamics; Surface active agents

Publication Date


Document Type


Student Type


Degree Name

Mechanical Engineering (MS)

Department, Program, or Center

Mechanical Engineering (KGCOE)


Satish Kandlikar

Advisor/Committee Member

Abhijit Mukherjee

Advisor/Committee Member

Jeffrey Kozak


Physical copy available from RIT's Wallace Library at TA357.5.M84 E64 2005


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