Movement of Planing Surfaces on Highly Compressible Soft Porous Media

Cuny City College, New York NY

Investigators

Abstract

PROPOSAL NO.: CTS-0432229 PRINCIPAL INVESTIGATOR: SHELDON WEINBAUM INSTITUTION: CUNY CITY COLLEGE MOVEMENT OF PLANING SURFACES ON HIGHLY COMPRESSIBLE SOFT POROUS MEDIA This grant is for a combined experimental and theoretical investigation on enhancing the lubricating pressures on planar lifting surfaces by having them glide over highly compressible soft porous media. Using concepts illustrated by the motion of a red cell moving through a tightly fitting capillary, it was shown by the PI that the drag force due to sliding friction can also be dramatically reduced if the elastic restoring force of the solid phase is small compared to the lift force generated by the transiently trapped fluid. Employing these insights, this grant explores a new concept for a future generation train which rides on a track with mechanical properties akin to goose down. Two different designs for the top porous surface of the track and the underside of the train car will be examined to determine which provides a superior sliding interface. The laboratory scale train-track model will be fully instrumented to measure the transient pressures developed in the soft porous track bed, the slope of the underside of the train car (the planing surface) as a function of its velocity and the forces and accelerations on the moving train car. A simplified theoretical model is also developed to predict the performance characteristics of the laboratory model and its full scale design. The research has exceptional potential for broad impact by integrating research and education into the curriculum. It has already piqued the interest of graduate and undergraduate students in both the mechanical and biomedical engineering departments. A 2004 paper published by the PI in Physical Evaluation Letters has also been covered by Science, Nature and nearly 60 other publications world-wide. The Discovery Channel has contacted the PIs for a demonstration of the concept and may produce a segment for the general public. The program and the novel experimental facility that is to be constructed will also be used as part of a summer enrichment program for high school students interested in science and engineering. The proposed research will also provide opportunities to outstanding undergraduates, particularly women and minorities.