It assumes an understanding of the basic principles of fluid mechanics, thermodynamics, compressible flow, and heat transfer. This version edited to remove itarcontrolled information. The transition of the boundary layer is inspected with tomographic particle image velocimetry tomopiv that is applied for the first time at mach 7. The phenomenon may occur, for example, at the upstreamfacing corner formed by deflected control surface on a hypersonic reentry vehicle, where the length of separation has implications for control effectiveness. Hypersonic boundary layer transition on reusable launch vehicles steven p. Study of effect of a smooth hump on hypersonic boundary layer stability by using pse donghun park1 and seung o park2.
Hypersonic boundarylayer transition on reusable launch vehicles. Hypersonic boundary layer transition measurements using no2. Xiaolin zhong, mahidhar tatineni, highorder nonuniform grid schemes for numerical simulation of hypersonic boundary layer stability and transition, journal of computational physics, v. Boundary layer transition and surface roughness effects in. Theory of reacting and hypersonic boundary layers dover books on engineering dorrance, william h. Boundarylayer transition is a problem that has plagued several generations of. A linear stability analysis is performed on the profiles to determine the amplification rates of naturally occurring disturbances, and this information is used with the e n method to predict the boundary layer transition location. On decoupling ablation effects on boundarylayer stability. Interaction between a shock wave and a boundary layer can produce a region of separated flow. Vehicles that are powered by airbreathing propulsion systems spend most of their atmospheric hypersonic. Verified, maneuverable hypersonic weapons would be formidable. Stabilization of a hypersonic boundary layer using a wavy surface dmitry bountin. Characterization of structural response to hypersonic.
The success of transition prediction relies on a fundamental understanding of the relevant physical mechanisms. The present work is devoted to the study of laminar boundary layer transition. Within the boundary layer, the flow is supersonic in the outer layer and subsonic near the wall, although the sonic line is located very close to the wall at high mach number. Schlieren visualization and processing of the boundary layer.
Aerothermodynamics of hypersonic shock wave boundary layer. Numerical and experimental investigation into hypersonic. When the approaching boundary layer is hypersonic and transitional the problem is particularly challenging and more reliable data is required in order to assess changes in the flow and the surface heat transfer, and to develop simplified models. Compared with full turbulent situation, when the boundary layer transition occurs, the unstart of the inlet is significantly mitigated, the heat transfer rate on the compression ramp decreases, both the total pressure recovery coefficient and mass flow rate increase at both design and offdesign points. Aerothermodynamics of hypersonic shock wave boundary layer interactions n. On decoupling ablation effects on boundary layer stability and transition. Boundary layer transition is a problem that has plagued several generations of aerodynamicists. Theory of reacting and hypersonic boundary layers dover books on engineering.
Turbulent flow is desirable at the entrance to the inlet to mitigate flow separations within the engine. Injectiongascomposition effects on hypersonic boundarylayer. The hypersonic boundary layer transition, or hybolt, experiment, will sit atop atks alv x1 launch vehicle when it launches from the midatlantic regional spaceport at nasa s wallops flight facility at wallops island, va. There are very few things about transition that are known with certainty, other than the fact that it happens if the reynolds number is large enough. A new transitionturbulence model considering the modes of instability and the compressibility effects is established. Hypersonic flow theory presents the fundamentals of fluid mechanics, focusing on the hypersonic flow theory and approaches in theoretical aerodynamics. Modeling flow transition in hypersonic boundary layer. Physics based prediction tools for hypersonic boundary layer transition hblt johnson and candler 2005 chemical and thermal nonequilibrium transition prediction accounting for flow physics undeformed panel deformed rigid wedge induced shocks heating expansion flow 1142015 3 fluid thermal structural interactions ftsi.
Hypersonic boundary layer transition measurements using. Examples for these abound in all applied sciences and to mention a few of these, we have, boundary layer, elasticplastic deformation, and shocks. Hypersonic boundary layer transition laminarturbulent transition of boundary layer is complex and not well understood at hypersonic speeds. Boundary layer transition and surface roughness effects in hypersonic flow. Hypersonic shock wave transitional boundary layer interactions can result in significantly greater peak surface heat transfer than laminar or turbulent interactions. A temperature gradient develops across the boundary layer due to the conversion of kinetic energy to heat as the flow velocity decreases. Aspects of hypersonic boundary layer transition control. The proposed scenario may inspire new strategies for the control of transition in hypersonic boundary layers. On hypersonic boundarylayer interactions and transition jstor. These arise either due to structural or behavioral changes in the medium. Laminarturbulent transition and shock waveboundary layer interaction. The abrupt deflection of flow, in the presence of ramp, leads to generation of shock wave emanating from the compression corner, which interacts with the boundary layer over the wall.
The ability to predict or delay transition and maintain laminar flow can have a significant. Laminarturbulent transition problems in supersonic and hypersonic flows. Hypersonic gas flow over cones is solved using computational fluid dynamics to obtain accurate boundary layer profiles. Abstract attachment line boundary layer transition on swept cylinders is studied in a low enthalpy hypersonic wind tunnel at m. Hence, the boundary layer experiences adverse pressure gradient near the region of flow deceleration or oblique shock. A large frame schlieren image technique is presented in the paper. Hypersonic boundary layer cross flow transition characteristics and control. Stabilization of a hypersonic boundary layer using a wavy surface. Thus the adverse pressure gradient caused by the compression corner can be felt upstream and thereby cause a separation of the flow. Highorder finitedifference schemes for numerical simulation.
The two primary factors driving this boundary layer growth are an increase in viscosity of the fluid and a decrease in density. The schlieren pictures obtained from wind tunnel test are processed and measured by a microdensitometer and a digital image processor. With pretreated computational grid and total enthalpy h0h0. The technique has been applied to visualization of the boundary layer transition on the surface of the cone in the hypersonic flow. Within the boundary layer in the first part of the model flat plate, it is possible to find a subsonic region. Hypersonic boundarylayer transition on reusable launch vehicles steven p. The increase in internal energy is realized as an increase in temperature. However, on a subscale vehicle such as the hyperx, the shorter forebody length is less likely to naturally transition prior to the. Transitional shockwaveboundarylayer interactions in. Graduate thesis or dissertation boundary layer transition. Transition and turbulence production in a hypersonic boundary layer is investigated in the mach 6 wind tunnel at peking university, using rayleigh scattering. Simulation of boundary layer transition on elliptic cones in.
A control surface of a hypersonic vehicle can be simulated with a ramp as shown in figure 1. Interaction between boundary layer and shock in hypersonic. Sweep angles of 60 and 70 are used and transition is detected by means of heat flux measurements. The simulation results showed that the flow transition is dominated by the instability of both the horseshoe vortex and the shear layer around the roughness. For velocity measurements in a hypersonic boundary layer flow undergoing laminartoturbulent transition, molecular tagging velocimetry mtv is a particularly attractive technique, as it. Since the pressure gradient normal to the flow within a boundary layer is approximately zero for low to moderate hypersonic mach numbers, the increase of temperature through the boundary layer coincides with a decrease in density. Influence of roughness on attachment line boundary layer. When the approaching boundary layer is hypersonic and transitional the problem is. The nonlinear coupling of dilatation waves and vortical waves inside the boundary layer and their linear coupling at the wall enable the highly localized strong peak of vortical wave which enhance the production of turbulence. Numerical study of hypersonic reacting boundary layer.
Direct numerical simulation on the receptivity, instability. The simulation of laminarturbulent tran sition in boundarylayer flows for entry scenarios can deliver estimates of flightrelevant physical properties such as drag. Because of this, the importance of understanding and predicting transition will be critical to the. Prediction and control of laminarturbulent transition in high. Hypersonic boundary layer transition significantly increases surface thermal heating and aerodynamic drag. Transitional shockwaveboundarylayer interactions in hypersonic. This book discusses the assumptions underlying hypersonic flow theory, unified supersonic hypersonic similitude, twodimensional and axisymmetric bodies, and circular cylinder. Hypersonic boundarylayer transition on reusable launch. Study of effect of a smooth hump on hypersonic boundary layer.
Hypersonic boundarylayer transition on blunt bodies with roughness. Simulation of boundary layer transition on elliptic cones in hypersonic flow. The maccormack technique is the technique utilized in this paper because of its simplicity and accuracy. Hypersonic boundarylayer transition on blunt bodies with. Me and recf criteria in conjunction with an intermittency function. Transition and turbulence production in a hypersonic boundary layer is investigated in a mach 6 wind tunnel using rayleighscattering visualization, fastresponse pressure measurements, and. Tomographic piv investigation of roughnessinduced transition. Finally, an example of a known unknown is boundarylayer transition. Boundary layer control for hypersonic airbreathing vehicles. Transitional shockwaveboundarylayer interactions in hypersonic flow volume 752. Detailed analysis of the experimental observations is provided. Consequently, the understanding of the flowfield structure of hypersonic shock wave transitional boundary layer interactions is im. Laminarturbulent transition correlations in supersonic.
Schneidery school of aeronautics and astronautics purdue university west lafayette, in 479071282 abstract laminarturbulent transition on the crew exploration vehicle cev, or orion is likely to be dominated by the e. We note that in proving the principle of impossibility of disturbance localization in the flows with nonweak interaction between the boundary layer and the outer hypersonic flow neiland, 1970b the flow pattern in a thin wall layer, in which velocity disturbances induced by a small pressure difference are of the same order as the velocity. Combined effect of overshoot and material temperature dependence on the flutter boundary characterization of structural response to hypersonic boundary layer transition. Transition and turbulence production in a hypersonic boundary layer is investigated in the mach 6 wind tunnel at peking university, using rayleighscattering visualization, fastresponse pressure measurements, and particle image velocimetry. It is found that, although the second mode is primarily an acoustic wave, it causes the. Laminarturbulent transition of hypersonic boundary layer. In 48th aiaa aerospace sciences meeting including the new horizons forum and aerospace exposition 20101064 48th aiaa aerospace sciences meeting including the new horizons forum and aerospace exposition. For compressible flow or flow at high speeds, however, increasing flow temperature due to friction heat near the body surface causes the boundary layer to become thicker as speed increases. Shock wave boundary layer interactions in hypersonic flows. Numerical and experimental investigation into hypersonic boundary. Flatplate boundarylayer transition in hypersonic flows stanford. Hypersonic boundary layer stability in the presence of thermo.