OBSERVING THERMOMIGRATION OF AIR BUBBLES IN A FLUID UNDER GRAVITY AT AN UNDERGRADUATE RESEARCH LABORATORY

摘要

An educational experimental project in fluid mechanics for space science or physics honors undergraduates is presented. The motion of air bubbles in a viscous silicone oil in response to buoyancy and Marangoni convection is studied with an experimental setup adapted to the undergraduate laboratory. The Marangoni effect or thermocapillary convection occurs when a temperature gradient is present in the oil which generates a surface tension differential over the bubbles. Results of measured radii and temperature gradients necessary to balance the buoyancy and Marangoni forces, along with computed Marangoni velocities are in good agreement with previous terrestrial and space experiments. (C) 1995 American Association of Physics Teachers. [References: 9]