This proposal is about understanding the mechanism by which insects breath. This is a project at the interface of microfluidics and bio-inspired fluid dynamics that could lead to the development of pumps for microfluidic networks, like those utilized when one places a miniature laboratory on a computer chip. Both theory and sophisticated experiments are proposed.
The goal is to investigate the bioflow environment around dragonfly nymphs that live underwater and seem to breath by generating a propagating wave through their body and by controlling the flow around their body with motion of their anal valve. The goals are to (1) elucidate the role of the wave in respiratory flow generation, and (2) study how the tri-leafleted anal valve controls the exhalatory and inhalatory flow. It is proposed to simultaneously measure four parameters: the kinematics of the hindgut chamber wall, the kinematics of the anal valve, and the flow inside and outside the chamber. Theory will be developed to describe this process, centered on the movement of internal waves between the tail and the midsection of the dragonfly. Sophisticated experiments involving Synchrotron X-Ray imaging at Argonne National Labs to visualize the internal flow in dragonfly larvae will be performed, while Particle Image Velocimetry (PIV) experiments will be conducted to examine the external flow. The nymph's pump can be viewed as a biological zero net mass flux (ZNMF) pump and results from the proposed work could lead to the design of ZNMF pumps with better flow generation and flow control. There are activities designed to reach out to the UCLA Community School, whose students are mostly underprivileged, first-generation college students. The PI will continue the production of research related spots that appear as YouTube videos reaching out to hundreds of thousands of people.
