Introduction to Transport Phenomena
- Random walk, Binomial distributions, and diffusion
- Transport coefficients, mean-free-paths, collision times
- Scattering and absorption, line escape formalism
- Langevin and Fokker-Planck equations; applications
Introduction to Radiative Transfer
- Definitions (specific intensity, mean intensity, flux moments)
- Equation of transfer limits (pure emission, absorption)
- Source function and formal solution
- Gaussian quadratures, Eddington & two-stream approx.
- Grey atmosphere (Milne solution) and emergent intensity
- Radiative equilibrium; effects of absorption and scattering
- Line formation; redistribution function; escape probability,
diffusion approximation
- Mean opacities (flux-weighted, Rosseland, Planck, Absorption means)
Boltzmann Equation and Applications
- Boltzmann Equation and Intro to Kinetic Theory
- Boltzmann H-Theorem, Entropy, Collision Integral
- Applications of the Boltzmann Equation
- Conservation Laws (moments of Boltzmann Equation)
Introduction to Fluid Dynamics
- The continuum model and requirements for a fluid
- Conservation laws, fluid kinematics (Eulerian, Lagrangian)
- Advective Derivative, Vector Fields, Vector Calculus
- Mass and Momentum Equations (Euler and Bernoulli)
- Vorticity, Vorticity Freezing, Vorticity Equation
- Bernoulli Theorem, Kelvin Circulation Theorem, applications
Strain Rate and Viscous Stresses
- Kinematics of Fluid Motion (strain, stress, relative motion)
- Stress-Strain Relations (Stress Tensor and Strain-Rate Tensors)
- Newtonian fluids (compressibility, viscosity coefficients, pressure)
- Derivation of Navier-Stokes Equation
- Reynolds Number and non-dimensional equations of motion
- Mechanical Viscosity (Classic Shear flows, Couette flow, pipe flow)
- Energy Equations (First Law, Reynolds transport theorem, dissipation)
- Heat Equation (conduction, diffusion, entropy, Bernoulli function)
Applications to Accretion Flows
- Spherical Accretion, Outflows, Gravitational Collapse
- Wind Equation (de Laval Nozzle, sonic point, topology)
- Bondi-Hoyle Accretion, Solar Wind critical solutions
- Accretion Disk Theory (Keplerian disks, viscous couples)
- Conservation laws (mass, angular momentum flux)
- Accretion rates, angular momentum distribution, viscosity
Magnetohydrodynamics (MHD)
- Basic assumptions for magnetized fluid
- Conservation laws, Ideal MHD equations
- Magnetic diffusion equation (finite conductivity)
- Hydromagnetic equilibria (pressure, tension)
- Examples (force-free fields, magnetic flux tubes, etc)
- Waves (Alfven waves, Magnetosonic waves)
Shock Waves
- Sound Waves and "signal speeds"
- Steepening to shock waves (PDEs and characteristics)
- Adiabatic (Rankine-Hugoniot) Jump Conditions
- Post-shock conditions, entropy generation
- Oblique shocks
- Similarity solutions (Sedov-Taylor, Wind-driven bubbles)
Fluid Waves and Instabilities
- Surface and Interface waves
- Role of surface and dynamic boundary conditions
- Gravity waves (shallow and deep-water limits)
- Dispersion relations, Stability and instability
- Rayleigh-Taylor and Kelvin-Helmholtz Inatbilities
- Gravitational (Jeans) Instability (perturbation analysis)
- Convective Instability (Schwarzschild criterion, entropy)
- Stable atmospheres (Brunt-Vaisala frequency, buoyancy)
Intro to Turbulence
- Characteristics of turbulent flows
- Chaotic, nonlinear, diffusivity, vorticity cascades. dissipation
- Kolmogoroff spectrum, eddy cascade, scaling relations
- Molecular vs Eddy Viscosities
- Taylor and Kolmogorov microscales
- Introduction to numerical simulations of turbulence