Fluid Behavior in a Rectangular Cell under a Parabolic Flight Using an Airplane

Abstract

The Convection Diffusion Unit (CDU), which is going to be flown in 1994 aboard the planned IML-2 mission, will use electrolysis and a pH indicator to track diffusion and fluid flow within an experimental container. This paper presents results from a set of preliminary low-gravity experiments used to confirm the effectiveness of this method for tracing fluid motions.Pitch of the airplane as well as acceleration along all three axes were measured together with a video of the fluid, in which movement was clearly indicated by the dye. Large rotations of the fluid were observed not only during the parabolic sections of the flight, but before and after as well. Magnitudes of the rotations were clearly seen to differ according to the pitch of the nose, acceleration of the airplane, and density distribution of the liquid.