Research

TBLs over aerodynamic surfaces commonly experience pressure gradients that vary in space and in time. The response of a boundary layer under these situations depends both on the local pressure gradient and the history of pressure gradients it encountered earlier in space or time. An understanding of the history effects, therefore, is critical in accurately predicting phenomena like flow separation. In this theme of research, we systematically subject TBLs to complex spatial and temporal pressure gradient histories, capture the response using pressure measurements and velocimetry techniques, and study the data using traditional and novel data analyses tools. 

The dynamics of turbulent boundary layers are driven by different cycles and nonlinear interactions between space and time-coherent structures. These structures interact and modulate each other such that properties such as skin friction are affected by them and they also serve as a catalyst for the development of reduced-order modeling of turbulent boundary layers. Our work proposes also a height variation interaction between large-scale structures and small-scale structures. We seek to understand and leverage this relationship to describe turbulence more efficiently. To probe mechanisms of interaction, we study the interaction of a cylinder wake with a turbulent boundary layer.

Improvement in aerodynamic performance is possible thanks to flow control techniques. Aspects such as flow stabilization, separation and reattachment, drag reduction, etc. have been leveraged to optimize the performance of different transportation methods and energy-generating machinery. In our group, we look at different scenarios and study the physics of different scenarios for turbulent flows.