The course will build up the students’ understanding and knowledge of hypersonic flows, both in terms of theoretical physics aspects as well as the prediction methods available for design and analysis. More specifically, on completion of the course students will be able to: Understand the complex physics of hypersonic flow, the importance of Mach number, temperature and density, and how this drastically differs from non-hypersonic flows; Assess whether a particular application involves aspects of hypersonic flow; Understand the design challenges for hypersonic flight, especially the thermal and loading constraints to hypersonic flight trajectories; Understand and predict the effects of hypersonic boundary layers and associated frictional heating, as well as the physics of interactional effects on realistic configurations that can limit severely vehicle performance; Understand the physics of how energy is stored within gases; Appreciate the role of radiation in hypersonic heating problems; Appreciate the methods of non-continuum molecular dynamics as well as the revisions needed to continuum CFD models to account for real gas effects.
teacher profile teaching materials
II. Inviscid hypersonic flows. Hypersonic limit relations for shock waves. Newtonian theory. Newton-Busemann centrifugal corrections. The role of the density ratio in hypersonics. The combined limit of high Mach numbers and large density ratios. The Taylor-Maccoll theory for supersonic flows over cones. Mach-number independence principle. Van Dyke’s small-disturbance equations for slender bodies. Tsien’s hypersonic similarity parameter. The shock standoff distance from blunted bodies. Shock layer and entropy layer.
III. Viscous hypersonic flows. The role of flight altitude. Boundary-layer transition phenomenology. Endo-atmospheric and trans-atmospheric hypersonic vehicles. Non-continuum effects. Compressible laminar boundary layers. Recovery factor. Basic self-similar formulations for flat plates and forebody stagnation-point flows. The Fay-Riddell correlation. Aerodynamic heating.
IV. High-speed thermo-chemical effects. Non-calorically and non-thermally perfect effects at high flight speeds. Air dissociation, ionization, and vibrational excitation. Chemical and vibrational non-equilibrium effects.
V. Re-entry aeromechanics. Particle mechanics of re-entering spacecrafts. The role of the ballistic coefficient, the nose curvature, and the atmospheric density gradient. Deceleration, heating, and downrange precision landing.
VI. Computational methods for hypersonic flows
Programme
I. The hypersonic gas environment. Historical aspects. Engineering applications: Re-entry spacecrafts, hypersonic cruise aircrafts. Distinguished flight conditions leading to hypersonic flow phenomena.II. Inviscid hypersonic flows. Hypersonic limit relations for shock waves. Newtonian theory. Newton-Busemann centrifugal corrections. The role of the density ratio in hypersonics. The combined limit of high Mach numbers and large density ratios. The Taylor-Maccoll theory for supersonic flows over cones. Mach-number independence principle. Van Dyke’s small-disturbance equations for slender bodies. Tsien’s hypersonic similarity parameter. The shock standoff distance from blunted bodies. Shock layer and entropy layer.
III. Viscous hypersonic flows. The role of flight altitude. Boundary-layer transition phenomenology. Endo-atmospheric and trans-atmospheric hypersonic vehicles. Non-continuum effects. Compressible laminar boundary layers. Recovery factor. Basic self-similar formulations for flat plates and forebody stagnation-point flows. The Fay-Riddell correlation. Aerodynamic heating.
IV. High-speed thermo-chemical effects. Non-calorically and non-thermally perfect effects at high flight speeds. Air dissociation, ionization, and vibrational excitation. Chemical and vibrational non-equilibrium effects.
V. Re-entry aeromechanics. Particle mechanics of re-entering spacecrafts. The role of the ballistic coefficient, the nose curvature, and the atmospheric density gradient. Deceleration, heating, and downrange precision landing.
VI. Computational methods for hypersonic flows
Core Documentation
Notes distributed by the teacher.Reference Bibliography
Anderson, J.D.Jr, “Computational Fluid Dynamics – The Basics with Applications”, McGraw-Hill, 1995 Anderson, J.D.Jr "Hypersonic and High-Temperature Gas Dynamics" - AIAA EducationAttendance
Attending the course is not mandatory but highly recomended.Type of evaluation
Evaluation of the level of learning achieved by the student will be verified by oral exam with a possible discussion on the laboratory experience and theoretical exercises. All the reports on practical applications are due by one week from the end of the course and they should be redacted in English.