Research

Primary research experiences and interests: Fluid dynamics ▪ experimental techniques in fluids (PIV, LDA, hot-wire, pressure) & acoustics ▪ ABL & environmental flows ▪ wall-bounded turbulence (smooth/rough) ▪ real-time flow control ▪ design & optimisation ▪ air breathing and rocket propulsion ▪ skin-friction drag reduction ▪ shock wave boundary layer interaction ▪ jet noise (lab-scale, full-scale) ▪ nonlinear acoustics ▪ acoustic metamaterials ▪ reduced-order modeling ▪ stochastic tools ▪ transient signal processing.

 

Data & Scripts

 

Turbulent boundary layers and high-Reynolds-number turbulence

  • Wall-coherent structure and the kx-1 spectral signature of the streamwise velocity fluctuations in turbulent boundary layers (TBLs).
  • Direct measurements of local wall-drag in smooth- and rough-wall TBLs.
  • Large-scale modulation and large-scale arrangement of small scales in high Reynolds number TBLs.
  • Real-time, active control of large-scale structures in high Reynolds number TBLs.

 

Aeroacoustics of high-speed jets and rocket nozzle flows

  • Aeroacoustic aspects of heated and unheated supersonic jets.
  • Nonlinear acoustic waveform distortion in noise fields of intense exhaust jets.
  • Crackle-noise emitted by supersonic jets.

 

Unsteady aerodynamics within supersonic nozzles

  • Shock wave boundary layer interaction (SWBLI) in overexpanded, large area ratio nozzles.
  • Side-load unsteadiness of thrust-optimized/truncated-ideal-contoured nozzles.
  • Transient unsteadiness during start-up and shut-down.
  • Vibro-acoustic loads during start-up, representative of nozzle ignition.

 

Stochastic tools, reduced-order modeling and system ID

  • Reduced-order models and system identification of complex data (mode decompositions, input-output analysis).
  • Stochastic estimation techniques (linear & higher-order).
  • Signal processing: spectral analysis and joint-time frequency distributions.