Fluids Seminar – February 10, 2020 – Dr. Vaibhav Joshi

Modeling and Physics of Bat Flight

Dr. Vaibhav Joshi

When: February 10, 2019 | 4 PM
Where: CEME 2202 | 6250 Applied Science Lane

Abstract: Flexible multibody systems consisting of joints are found in applications ranging from biological, such as the musculoskeletal system of animals (bones connected by ligaments), to industrial applications in marine/offshore, rotor dynamics and automobile/aerospace engineering. Of particular interest is the anatomical wing of a natural flyer (bird, insect or bat) which consists of bones (Humerus, Radius and Metacarpals) connected to each other by joints, with feathers (birds, insects) or membranes (bats) attached to the bones. Considering the dramatic advantages of biological wings, there is a growing trend in aeronautical engineering applications on the exploration of the design approaches of novel micro air vehicles (MAVs) and unmanned aerial vehicles (UAVs) by incorporating the understanding of flapping flight dynamics of birds and bats. A particular emphasis is to make these next-generation air vehicles more efficient, cleaner and intelligent in complex environments by means of bio-inspiration and bio-mimetic designs. There are numerous research questions related to animal flight mechanisms and biomechanics of the natural flyers, which could be crucial in such designs.

In contrast to birds and insects, bats utilize adaptive wing flexibility, wing span morphing and articulated wing kinematics for maneuverability and agility during flight. The present study focuses on the development of a flexible multibody variational fluid-structure interaction computational framework to model such complex flapping dynamics. We investigate the flapping dynamics of a full-scale bat using wing geometry and physical properties similar to the Pallas’ long-tongued bat Glossophaga soricina. We find that the flexible wings generate more unsteady lift compared to the rigid counterpart owing to the high wing-tip velocity due to the elastic deformation of the wings. Insights gained from the present study will be beneficial to develop novel designs for enhancing the maneuverability and flight agility of next-generation engineered flying vehicles (e.g., drones and micro-air vehicles) at low Reynolds number.

Biography: Vaibhav Joshi is a postdoctoral research fellow at the Computational Multiphysics Laboratory at UBC. He completed his Ph.D. in Computational Mechanics at the National University of Singapore where he worked on multiphase fluid-structure interaction problems. Currently, he is working on developing a flexible multibody numerical framework for bio-inspired flying vehicles.