Fluid and Fluid Structural Dynamics
This research area in the School encompasses the behaviour of fluids (liquids and gases), and the two-way interactions between fluids and embedded structures known as Fluid-Structure Interaction (FSI) where the motion of a structure or boundary influences the flow, which in turn moves or deforms the structure. FSI is crucial to a full understanding of many problems in design and Nature alike. For high speed (supersonic or hypersonic) flows there may be additional coupling with temperature effects known as Fluid-Thermal-Structure Interaction (FTSI), where frictional heating of the fluid and structure can create additional stresses and deformations in structures as well as alter fluid properties. Fluids may be almost incompressible (e.g. water) or compressible (e.g. air), laminar or turbulent, Newtonian (stress and strain linearly related as in most pure fluids) or non-Newtonian (non-linear stress-strain relationships such as shear thickening or shear thinning, common in many fluids with embedded particles such as blood).
Researchers in the School are examining a wide variety of fluid regimes and application areas, in both fundamental and applied studies. These include:
- FSI and fatigue in subsonic and supersonic flow in gas turbines; and hypersonic flows in scramjets;
- Blast and cavitation effects on deformable structures;
- Fluidic thrust vectoring using shocks to turn the flow rather than using actuators;
- Shock structure interactions for projectiles in close proximity to walls;
- FSI of insect wings, learning from Nature in the optimization of flapping kinematics and structural stiffness distributions for maximum lift and power economy;
- Stability and control of flapping-wing based drones;
- Vortex dynamics for power generation from flapping foils and deformable structures such as flags and filaments;
- Machine learning in fish swimming for schooling and robust adaptation to changing flow environments;
- Cell transport and deformation in blood flows, aimed at drug delivery mechanisms;
- Particulate separation in Newtonian and non-Newtonian flows.
Tools include experimental facilities such as a supersonic blowdown wind tunnel and a hypersonic shock tunnel, and expertise in the development of in-house numerical codes based on Navier-Stokes and Lattice Boltzmann flow solver approaches, with immersed boundary methods for robust treatment of large boundary motions and deformations.
Hypersonic flow over a deformable plate.
Simulation of vortex behavior for a tandem flapping foil turbine.
Trans-sonic projectiles in ground effect.
Flow around a flexible insect wing model