We are interested in the role of fluid forces during locomotion and morphogenesis. One ongoing project is focused on understanding the aerodynamics of flight in the smallest insects. Our work shows that fluid dynamics during flapping flight changes below a Reynolds number of about 40. This regime change corresponds to a change in the behavior of the vortex wake behind the flapping wing which results in a drop in the relative lift forces generated during flight. Many tiny insects use the clap and fling mechanism to compensate for the drop in lift. The consequence of this behavior, however, is that very large drag forces are required to peel the wings apart at the beginning of each downstroke. We are now exploring the role of wing flexibility and wing bristles in reducing drag during clap and fling.
Another current project investigates the role of fluid forces during the development of the embryonic vertebrate heart. Recent work suggests that the early embryonic heart beat does not pump blood for the purpose of convective transport, but rather aids in the shaping and maturation of the developing heart. The focus of this project is to determine whether or not transitions in fluid dynamics could also signal heart chamber morphogenesis through mechanotransduction. This idea is being tested using numerical simulations and physical models to determine the developmental stage(s) at which large scale fluid dynamic transitions occur. We are also exploring the smaller scale fluid dynamics that occur close to the endothelial layer of the developing heart.