A Multi-Fidelity Computational Framework for Analyzing Flapping Flight

Understanding the unsteady fluid structure interactions in flapping flight is challenging and requires a multi-disciplinary approach involving synergistic experiments (Brown University, U. of Maryland), theory (Brown University/MIT/Oregon State University) and computations(MIT/Oregon State University). In this Multidisciplinary University Research Initiative (MURI) between Brown University, MIT, U. of Maryland, and Oregon State U., the research focus is to develop a deeper understanding of bat flight (and more generally mammalian flight). Bat flight presents significant challenges in all aspects of the project ranging from low Reynolds number flight, experimental data collection in unpredictable flight conditions to highly unsteady, large deformation (highly anisotropic materials), fluid-structure interactions.

To achieve the computational goals we are implementing and using a multi-fidelity computational toolbox to model the fluid dynamics and structural interactions in flapping flight. Due to the multi-fidelity nature of the approach, the research questions and objectives can be addressed using the appropriate tool(s) at the appropriate level(s) of refinement. The effective and efficient analysis of the research questions is strongly related to the ability to answer the necessary questions at lower fidelity levels, prior to increasing the cost of the computation through higher fidelity analysis. For example, when simple trend based trade-off analysis is desired, the use of a high fidelity Navier Stokes fluid dynamics solver (3DG) is overkill compared with a lower fidelity unsteady potential flow analysis (FastAero, ASWING, or HallOpt); however, to examine the near wing flow structures the high fidel