Learn · Fluid Dynamics for Astrophysics
Lecture 26 of 65Week 5
Propagation of sonic information, shock tube problem and piston problem
Prof. Prasad Subramanian · IISER Pune
Credits and licence
- From
- Fluid Dynamics for Astrophysics, IISER Pune (at NPTEL)
- Licence
- CC BY-NC-SA, as NPTEL states it. Non-commercial use only.
- Attribution
- NPTEL states: "Distributed under Creative Commons Attribution-ShareAlike / CC BY - NC - SA", beside a BY-NC-SA badge. Coordinated by IIT Madras.
- Who can watch
- Teens profiles and older. How courses are placed
All the lectures
- Introduction to the course
- Continuum hypothesis, distribution function and stress-viscosity relation
- Continuum hypothesis, distribution function and stress-viscosity relation - Recap
- Fluid Kinematics
- Fluid Kinematics - Recap
- Conservation laws: Mass conservation and incomprehensibility
- Conservation laws: Momentum conservation and Euler equation
- Conservation laws - Recap
- Potential flows
- Bernoulli constant, its applications and voracity equation
- Recap - Potential flows, Bernoulli constant and its applications
- Voracity dynamics -- Kelvin's voracity theorem and Magus effect
- Navier-Stokes equation
- Navier-Stokes equation (contd.) and energy equation
- Energy equation in a conservative form
- Boundary conditions in Navier-Stokes equation, d'Alembert's paradox
- Poiseuille flow, deriving viscosity from microscopics
- Dimensionless numbers -- Mach number, Reynolds number
- DimDimensionless numbers contd -- plasma beta, magnetic Reynolds number, Alfven Mach number, Prandl numberensionless numbers -- Mach number, Reynolds number
- Reynolds number and dynamic similarity
- Reynolds number recap, Low Re flows, and drag on a sphere (Stokes law)
- High Re flows -- turbulent drag law, vortex shedding and drag crisis
- Lift on a body, introduction to compressible flows
- Compressible flows -- derivation of sound speed and dispersion relation
- Subsonic and supersonic flows
- Propagation of sonic information, shock tube problem and piston problem
- Criterion for neglect of compressibility, method of characteristics
- Shock thickness
- Shock thickness recap, shock jump conditions
- Shock jump conditions (contd), transonic 1D flows, converging/diverging channels
- Coverging/diverging channels, de Laval nozzle and its application to astrophysical jets
- Spherically symmetric transonic flows
- Spherically symmetric transonic flows (contd)
- Solar wind : Parker's solution
- Solar wind : Modifications in Parker's solution
- Spherical accretion onto a compact object : Eddington luminosity and accretion rate
- Spherical accretion onto a compact object : Solutions for flow properties
- Spherical accretion (contd), disk accretion--Roche lobe overflow
- Disk accretion : Mass conservation and vertical hydrostatic equilibrium
- Disk accretion : Removal of angular momentum, Shakura-Sunyaev viscosity parameter
- Disk accretion : Viscous dissipation and the energy equation, two-temperature criterion
- Particle acceleration in astrophysical settings : Shocks and non-thermal energy distribution
- Particle acceleration in astrophysical settings : Diffusive shock acceleration
- Spherical blast waves : Bomb explosion and supernova explosion
- Spherical blast waves : Sedov-Taylor solution
- Spherical blast waves : Sedov-Taylor solution (contd.)
- Magnetohydrodynamics (MHD) : Introduction
- Magnetohydrodynamics (MHD) : The induction equation
- Magnetohydrodynamics (MHD) : Currents in MHD, momentum equation and magnetic stress tensor
- Magnetohydrodynamics (MHD) : Magnetic stresses and magnetic buoyancy
- Magnetohydrodynamics (MHD) : Plasma beta, force-free fields and potential configurations
- Magnetohydrodynamics (MHD) : Magnetic flux-freezing
- Magnetohydrodynamics (MHD) : Magnetic flux-freezing (contd.), magnetic dynamos
- Magnetohydrodynamics (MHD) : Dynamo theory
- Magnetohydrodynamics (MHD) : Waves in MHD - Alfven waves
- Magnetohydrodynamics (MHD) : Waves in MHD - Alfven waves and magnetosonic waves
- Magnetohydrodynamics (MHD) : Waves in MHD - Magnetosonic waves
- Magnetohydrodynamics (MHD) : Shocks in MHD
- Magnetohydrodynamics (MHD) : Shocks in MHD - Shock jump conditions
- Non-ideal MHD : Introduction to magnetic reconnection
- Non-ideal MHD : Magnetic reconnection - The Sweet-Parker model
- Non-ideal MHD : Magnetic reconnection - The Petscheck model
- Sun's atmosphere : Solar corona and the coronal heating problem
- Solar eruptions : Coronal Mass Ejections (CMEs) and solar flares
- Live Session 26-02-2021