We acoustically modulated the localized surface plasmon resonances (LSPRs) of metal nanostructures integrated within microfluidic systems. An acoustically driven micromixing device based on bubble microstreaming quickly and homogeneously mixes multiple laminar flows of different refractive indices. The altered refractive index of the mixed fluids enables rapid modulation of the LSPRs of gold na...

Thin aerofoils are prone to localized flow separation at their leading edge if subjected to moderate angles of attack α. Although 'laminar separation bubbles' at first do not significantly alter the aerofoil performance, they tend to 'burst' if α is increased further or if perturbations acting upon the flow reach a certain intensity. This then either leads to global flow separation (stall) or t...

Accurate and efficient numerical predictions of flutter is essential for the turbomachinery industry. The decoupled method has been main workhorse industry decades thanks to its low computational resources required. However, there arises need an innovative propulsion architecture a lightweight material, which hinders accuracy effectiveness method. Hence, use fully-coupled methods steadily incre...

This study investigates a mechanism for controlling separated flows around an airfoil using synthetic jet (SJ). A large-eddy simulation (LES) was performed leading-edge separation flow at the chord Reynolds number of 63 000 and angle attack 12°. The present LES resolves turbulent structure inside deforming SJ cavity with grid. An optimal actuation-frequency band is identified between normalized...

A high-fidelity computational analysis carefully validated against concurrently obtained experimental results is employed to examine self-noise radiation of airfoils at transitional flow regimes, with a focus on elucidating the connection between unsteady behavior laminar separation bubble (LSB) and acoustic feedback-loop (AFL) resonant interactions observed in airfoil boundary layers. The para...

We present and analyse a model for the spherical pulsations and translational motions of a pair of interacting gas bubbles in an incompressible liquid. The model is derived rigorously in the context of potential flow theory and contains all terms up to and including fourth order in the inverse separation distance between the bubbles. We use this model to study the cases of both weak and moderat...

On applying large eddy simulation (LES) to engineering interest, one of the keys is to obtain two-order low-dissipation shock-capturing schemes adapted to LES. Therefore, the preconditioning method for all speed flows is adopted. However, the accuracy of preconditioned schemes is not satisfactory because of the poor performance of stability of preconditioning techniques especially in viscous fl...

This thesis presents a high-order Implicit Large-Eddy Simulation (ILES) approach for simulating transitional aerodynamic flows. The approach consists of a hybridized Discontinuous Galerkin (DG) method for the discretization of the Navier-Stokes (NS) equations and a parallel preconditioned Newton-GMRES solver for the resulting nonlinear system of equations. The combination of hybridized DG metho...

A symmetrical NACA 0018 airfoil is often used in such applications as small-to-medium scale vertical-axis wind turbines and aerial vehicles. review of the literature indicates a large gap experimental studies this at low moderate Reynolds numbers previous century. This has limited potential development classical turbulence models, which range predict lift coefficients with insufficiently accura...

Flow separation limits the efficiency of low-pressure turbines (LPTs) in aircraft engines. Experiments with vortex generator jets (VGJs), conducted in AFRL's low-speed cascade at Wright-Patterson AFB, have demonstrated dramatic reductions in separation losses. The critical science that will enable this design innovation to reach its potential is a comprehensive understanding of the effect of VG...