A5009484235- Computational Fluid Dynamics and Aerodynamics
- Fluid Dynamics and Turbulent Flows
- Plasma and Flow Control in Aerodynamics
- Laser-Plasma Interactions and Diagnostics
- Aerodynamics and Acoustics in Jet Flows
- Laser-induced spectroscopy and plasma
- Combustion and flame dynamics
- Laser-Matter Interactions and Applications
- Rocket and propulsion systems research
- Gas Dynamics and Kinetic Theory
Seoul National University
2018-2023
Transient behaviors of unstarting and unstarted flows have been experimentally investigated in a Mach 6 freestream flow with without boundary-layer suction scramjet isolator. The test model has rectangular cross section simulates the full flowpath engine. control is activated by fast-acting solenoid valve while an unsteady evolves scramjet. A nonreacting jet injected into combustor to mimic choking scramjets. choked then initiates unstart shock wave that reaches inlet induces downstream...
A numerically accurate method for solving quasi-one-dimensional transonic flow with a system of ordinary differential equations (ODEs) has been developed to estimate the performance high-speed propulsion system. Specifically, ramjet engines are thermally choked in combustor region. which solution processes undergo mathematical singularity problem. This incurs various numerical difficulties because derivatives indeterminate at sonic condition and cannot march streamwise direction, requiring...
The boundary-layer suction control of unstarting flows in an ethylene-fueled dual-mode scramjet was experimentally investigated the present study. A model with a rectangular cross-section tested Mach 4.5 high-enthalpy freestreams, and ethylene jet injected into to trigger inlet unstart. Wall-pressure measurements electronically excited CH (CH*) chemiluminescence imaging were performed characterize behavior flows. overall equivalence ratio engine increased induce unstart, which detected based...
This research delves into liquid fuel injection in scramjet combustors, with a focus on the effects of injector length-to-diameter ([Formula: see text]) ratios and temperatures, spanning from ambient to superheated states. Efficient atomization within short residence times liquid-fueled supersonic combustors is crucial for maximizing combustion efficiency. Initial investigations quiescent environment aimed isolate impact geometry temperature, utilizing quantitative analysis diffused backlit...
View Video Presentation: https://doi.org/10.2514/6.2022-0202.vid Unsteady fluid-combustion interactions in optical axisymmetric scramjet models are experimentally investigated Mach 4.5 flows. The reveals generic fluid and combustion dynamics without the corner boundary-layer effects that can distort flame propagation rectangular geometries. Fluid characterized by pressure measurement on combustor wall along entire flowpath. High-speed chemiluminescence luminosity imaging used to visualize...
A novel two-component seedless velocimetry is devised using shockwaves from laser-induced plasmas (LIP) generated by focused nanosecond laser pulses (532 nm). This utilizes two pairs of continuous-wave (CW) beams traversing the region adjacent to LIP in parallel with horizontal path pulse. Two probe a pair (633 nm) are above and below, other (780 on sides LIP. Each diode emitting beam travelling back forth between right-angle prism mirror hollow-roof retroreflector be terminated fast...