MJ2485 Introduction to Unsteady aerodynamics 7.5 credits

Introduktionskurs instationär aerodynamik

Please note

The information on this page is based on a course syllabus that is not yet valid.

  • Education cycle

    Second cycle
  • Main field of study

    Mechanical Engineering
  • Grading scale

    A, B, C, D, E, FX, F

Course offerings

Autumn 19 for programme students

Autumn 18 for programme students

Intended learning outcomes

The course aims at providing students with the fundamental theory of aerodynamics and to introduce students to the unsteady aerodynamics and aeroelasticity.

After completing the course the student will be able to:

- Compute the aerodynamic forces and moments on a profile from a velocity or pressure distribution

- Differentiate between the sources of drag, their cause and characteristics

- Simplify important equations using dimensional analysis

- Calculate the potential flow around a profile using the method of singularities and conformal mapping

- Calculate the aerodynamic forces on a airfoil profile using the thin airfoil theory -

- Understand the link between singularities and panel methods

- Calculate the inviscid aerodynamic forces on a three-dimensional wing from its two-dimensional characteristics

- Calculate the boundary layer from the potential flow solution

- Determine the best approach to compute the boundary layer (self-similar profile, integral method, ...)

- Compare experimental measurements, with theoretical and/or numerical results

- Differentiate between the physics of laminar and turbulent flows

- Determine the characteristics of transition to turbulence and flow separation from the pressure distribution and Reynolds number

- Average important equations using Reynolds approach

- Estimate the aerodynamic forces in the supersonic and transsonic regimes for thin airfoils

- Develop structural equations of motion for linear and nonlinear elastic structures using Hamilton's Principle and Lagrange's equations including the effects of external forces.

-Using simplied representations of the aerodynamic forces on an elastic structure, develp the aeroelastic (coupled fluid-structural) equations of motion.

-Master methods for solving the aeroelastic equations of motion including the concepts of transfer function for simple harmonic motion in time, Fourier series for periodic motion, Fourier transforms for aperiodic motion and power spectra for random motion.

- Explain physical phenomena of divergence, control surface reversal, flutter and gust response and how they can be described by solutions to computational aeroelastic models and also can be observed in wind tunnel experiments.

- Develop a fundamental understanding of the classical potential flow theory of unsteady aerodynamics.

Course main content

Aerodynamics is the study of fluid flows around or within solid bodies. One of the major objectives of aerodynamics is to predict the forces and moments that are exerted by the fluid on the body, or to predict the heat transfers between the fluid and the body.

The first part of the course  presents the most fundamental aspects of aerodynamics. Following topics are covered:

- Aerodynamic forces and moments: lift and drag, pitching moment, airfoil polar, aerodynamic center, center of pressure

- Incompressible potential flows, singularities (vortex, source, doublet), d'Alembert principle, circulation

- Superposition of fundamental solutions, Rankine oval, lifting cylinder, Kutta-Joukowski theorem, conformal mapping, complex formalism, Joukowsky airfoil

- Thin airfoil theory: line distribution of singularities, effect of thickness and camber, Kutta condition

- Panel methods: potential-based, vortex-based, source-based, equivalence between source, doublet and vortex-based methods

- 3D wings: vortex sheet, Prandtl lifting line theory for large aspect ratio wings, distribution of circulation, induced drag, downwash velocity, elliptic lift distribution, optimal wing, general lift distribution

- Boundary layers: concepts and definitions, boundary conditions, thickness, von Karman integral equation, flow separation and airfoil stall, transition to turbulence

- Laminar boundary layer: self-similar solution (Blasius, Falkner-Skan), Pohlhaussen method, Thwaites method

- Turbulent boundary layer: transition, characteristics, Reynolds-averaging, Head method, log law

- Compressible aerodynamics: compressible potential flow, Prandtl-Glauert equation, flow past a thin airfoil (subsonic, transonic, supersonic)

The second part of the course focuses on the basics of aeroelasticity or the dynamics of fluid-structure interaction. Following topics are covered:

- Coupled equeation of motion

- Solution to aeroelastic equation of motion

- Static aeroelasticity (divergence, control surface reversal)

- Dynamic aeroelasticity (flutter, gust, forced response)

- Nonsteady aerodynamics of lifting and non-lifting surfaces   

Disposition

The course runs over three periods, P1, P2 and P3.

TEND exam after P2 (4.5ECTS), grade A-F

TENA exam after P3 (3ECTS), grade A-F

Eligibility

Engineering mathematics, BSc level

Turbomachinery MJ2429

Only for TAETM

Literature

"Fundamentals of Aerodynamics", John Anderson Jr., 5th edition, McGraw and Hill, ISBN 978-0-07-339810-5

"A Modern Course in Aeroelasticity ", Earl H. Dowell,  Springer, Fifth Edition, 2015,ISBN 978-3-319-09453-3

Föreläsningsanteckningar distribueras via Canvas plattformen

"Fundamentals of Aerodynamics", John Anderson Jr., 5th edition, McGraw and Hill, ISBN 978-0-07-339810-5

"A Modern Course in Aeroelasticity ", Earl H. Dowell,  Springer, Fifth Edition, 2015,ISBN 978-3-319-09453-3

Föreläsningsanteckningar distribueras via Canvas plattformen

Examination

  • INL1 - Hand in exercise, 3.0, grading scale: A, B, C, D, E, FX, F
  • TEND - Examination, 4.5, grading scale: A, B, C, D, E, FX, F

TEN A, 3 ECTS, A-F

TEN B, 1,5 ECTS, A-F

TEN C, 3 ECTS, A-F

Offered by

ITM/Energy Technology

Examiner

Andrew Martin <andrew.martin@energy.kth.se>

Version

Course syllabus valid from: Autumn 2019.
Examination information valid from: Autumn 2019.