Assistant Professor Jeffrey Allen (MEEM) has received $147,286, the first year of a five-year $400,588 National Science Foundation CAREER Award.

His proposal, "Gas-liquid Interface Dynamics and Dissipation Mechanisms in Capillary-scale Two-phase Flow," continues his investigations in capillary flow, or how and why gases and liquids move (or fail to move) through tiny channels, such as those found in hydrogen fuel cells.

Two-phase flow, a branch of fluid mechanics, examines systems such as boilers, in which a gas and a liquid are present. Allen investigates two-phase flow through very narrow tubes, which has applications in microelectrical-mechanical systems, microscale heat exchangers, and space-based processing and thermal control technologies, as well as fuel cells. Two-phase flow at this very small scale is not well understood. With his CAREER award, Allen aims to develop design tools that will improve the engineering of these systems. Ultimately, he expects to develop advanced technologies that will improve water management in fuel cells.

Fuel cells generate water vapor as a byproduct, and as a result, they can literally freeze in winter or flood if the water is not drawn away. Managing water has been a major obstacle to the commercialization of fuel-cell-powered vehicles.

Undergraduate and graduate students will all be involved in the project, creating a stream of student talent in the growing field of microscale devices and fuel cells.