Experimental investigation of ramp-induced shock–boundary-layer interactions in the presence of a sinusoidal roughness strip

Experimental investigation of ramp-induced shock–boundary-layer interactions in the presence of a sinusoidal roughness strip

Mc Carthy, Robert (TU Delft Aerospace Engineering)

Schrijer, F.F.J. (mentor)
van Oudheusden, B.W. (graduation committee)

Delft University of Technology

Aerospace Engineering

2020-12-17

Of the many challenges involved in developing reliable and sustainable spaceflight, perhaps none are so dangerous and difficult to study as the aerothermodynamic conditions involved when re-entering the atmosphere. These dangerous conditions typically occur due to a variety of flow phenomena, one of which is shock—boundary-layer interactions (SBLIs), which commonly occur in the vicinity of a vehicle’s control flaps and involve the dynamic coupling of the adverse pressure of a shock and the subsonic nature of a viscous boundary layer. To properly understand SBLIs, it is important to understand how they amplify or decay upstream disturbances, which may offer deeper insight into how they operate. To this aim, the goal of this work is to observe and quantify how sinusoidal roughness strips introduce perturbations into a compression ramp SBLI system. This is achieved through experiments of various ramps and roughness strips on a flat plate with the Hypersonic Test Facility Delft (HTFD), wherein the Reynolds number, compression ramp angle, and sinusoidal strip wavelength (distance between peaks) are modified to directly observe the influence each has on the SBLI system. This work employs three measurement techniques: schlieren visualization, quantitative infrared thermography (QIRT), and oil flow visualization. This thesis quantifies and evaluates relationships between Reynolds number, ramp angle, and sinusoidal strip wavelength to surface heat flux and shear layer behavior, in addition to comparing how laminar, transitional, and turbulent flow conditions influence SBLI behavior.

Hypersonics
SWBLI
SBLI
shock--boundary-layer interactions
compression ramp
sinusoidal
high-speed
Schlieren
QIRT
Oil flow

http://resolver.tudelft.nl/uuid:16a17232-82eb-49fc-a0e6-0dcdedf73963

Student theses

master thesis

© 2020 Robert Mc Carthy