Principles of CFD | OpenFOAM Training | Course Modules
Part 1 — 2 days
Summary
- Flow, momentum and conservation
- Pressure, friction and forces
- Unsteady flow and turbulence
Velocity, Flow Rate and Conservation
- Velocity: no-slip boundary condition (BC), Poiseuille’s Law, inlet profiles, plotting profiles
- Flow through a surface: face areas, face zones, flow rates, discharge coefficient
- Conservation of mass: derivation, incompressibility, fluxes, intensive and extensive properties
- Mathematics: vectors, inner product, Gauss’s theorem, gradient, divergence
Forces
- Pressure: Bernouilli’s equation, relative and kinematic, gradients, probing pressure data
- Stress: Cauchy stress tensor, shear stress, pressure and identity tensor
- Newtonian fluid: fluid shear and rotation, rate of deformation tensor, viscosity
- Force calculation: force at a surface, force coefficients, particle drag modelling
Momentum
- Conservation of momentum: derivation, material derivative, advection, body forces
- Tensors: identity tensor, symmetric, skew, transpose, deviatoric, spherical
- Coding: mathematical constants, Reynolds number, drag
Internal flows
- Wall friction: Darcy-Weisbach friction factor, Reynolds number dependence
- Transition: laminar region (friction factor = 64/Re), transition region, turbulence
- Velocity profile: viscous sub-layer, log-law region, 1/7th power law
- Wall functions: underlying purpose, standard models, alternative wall models, roughness
- Coding: plotting the Moody chart
External flows
- Boundary layers: thickness estimate, Blasius solution, laminar and turbulent boundary layers, atmospheric boundary layer
- Flow regimes: separation, vortex shedding, transition in wake, shear layers
- Turbulence: power flux, deformation power, turbulent kinetic energy, turbulent pressure, cost of simulation, Reynolds-averaged modelling
- Shedding: frequency, Strouhal number (vs Reynolds number)
- Boundary conditions: total pressure, freestream, entrainment
- Mixing: Lagrangian particle tracking, scalar transport
- Diagnostics: lift coefficient, RMS period of shedding
Finite Volume Method
- Polyhedral mesh: cells, faces, boundary, patches
- Finite volume mesh: volumes, cell centres, face areas
- Matrix equations: matrix construction, sparse matrices
- Advection: advective derivative, linear, upwind, linear-upwind, limited-linear interpolation
- Time derivative: Euler, backward, Crank-Nicolson schemes, Courant number, time step
- Coding: area calculation
Part 2 — 2 days
Summary
- Heat, thermal physics, thermodynamics, heat transfer/CHT
- Buoyancy, dispersion and particles
- Waves, discontinuities and boundedness
Heat and thermal physics
- Conservation of energy: derivation, total energy, internal energy, mechanical kinetic energy, enthalpy, dissipation
- Temperature: thermodynamic scale, heat flux, Fourier’s Law, thermal conductivity
- Equation of state: ideal gas, the Boussinesq approximation, compressibility factor
- Fluid species: molar mass, Avogradro’s number, gas constant
- Heat capacity: at constant volume and pressure, thermal expansion and compressibility
- Transport properties: viscosity and thermal conductivity as a function of temperature, Prandtl number
- Coding: physical constants
Heat Transfer
- Convective heat transfer: Newton’s Law of Cooling, heat transfer coefficient, Nusselt number
- Lumped mass temperature: heat balance, Biot number, semi-implicit solution
- Conjugate heat transfer: multiple mesh regions, region coupling,
coupledTemperature
BC - Other: external temperature boundaries, heat sources, thermal boundary layers
- Coding: thermophysical transport, heat flux, object registry, weighted averages, global sum
Natural convection
- Buoyancy: gravitational body force, densimetric Froude number
- Boussinesq approximation: linearised temperature equation of state, limitations of linearisation
- Pressure: redefinition (p_rgh), boundary fluxes,
fixedFluxPressure
BC, relative / absolute pressure - Flow: estimating flow speed, turbulence generation, hot plumes, cross-flow, heating time, turnover time
Open channel flow
- Solution method: volume of fluid, boundedness, MULES, interface compression
- Flow regimes: subcritical, supercritical, Froude number, hydraulic jump, surface wave speed, inlet boundary condition, outlet pressure
- Diagnosis: water depth, flow rate, Froude number
- Coding: pointer list, flip map, ternary operator, writing files in parallel, sliced field, splice function
High-speed flows
- Flow regimes: subsonic, supersonic, Mach number, shock and expansion waves, boundary conditions, Mach number-area relationship
- Solution method: flux-splitting, explicit solution, Courant number limit
- Coding: skin friction coefficient, total pressure, retained total pressure, patch average
Finite Volume Method
- Diffusion: surface normal gradient, Laplacian
- Source terms: body force, boundedness
Why attend Principles of CFD?
The knowledge gap in CFD
- Computational fluid dynamics (CFD) principally involves fluid dynamics, heat and thermodynamics.
- These subjects are traditionally taught to be conveniently examined, with emphasis of pen and paper solutions.
- The science (especially thermodynamics) is often described for fluid systems rather than the fluid itself.
- Practitioners of CFD therefore have little useful knowledge from their studies to transfer to their work in CFD.
- The gap in knowledge — between what a CFD user knows and what they need to know — is widespread and growing.
Teaching fluid dynamics for CFD
- This course teaches fluid dynamics, heat and thermodynamics, numerical methods and algorithms for CFD.
- We use canonical (study) cases which provide a strong foundation for “real-world” engineering problems.
- Solutions are built upon the governing equations of mass, momentum and energy conservation in 3-dimensions.
- We demonstrate control volume analysis, which transfers easily to CFD with the finite volume method.
- Important empirical and analytical solutions are carefully chosen to demonstrate trends and help validate results.
Preliminary, diagnostic and objective calculations
- We encourage the use of quick calculations to prepare and monitor a simulation, and produce key results
- Dimensionless numbers are calculated to establish flow and heat transfer regimes prior to simulation.
- During the simulation itself, we calculate data which can be monitored and quality checked.
- We describe how to extract useful data from the simulation, e.g. to characterise a design.
- We teach OpenFOAM’s
coded
frameworks (code in input files) extensively, for one-time, quick calculations.
Top quality CFD training
The course was created and is delivered by Chris Greenshields and Aidan Wimshurst. It draws on the experience of Chris’s 16 years of OpenFOAM training, involving 800+ days with over 3500 participants. Aidan brings further experience from his Fluid Mechanics 101 channel on YouTube and the ensuing interaction with subscribers. The course builds upon the topics in Notes on Computational Fluid Dynamics: General Principles by Chris and Henry Weller (the creator of OpenFOAM).
Who Should Attend
Target Audience
- New users of OpenFOAM and/or new to CFD
- Postgraduates working in CFD with OpenFOAM
- Existing users with limited transferable knowledge in CFD
- CFD practitioners wishing to broaden their knowledge
Pre-requisites
- A science/engineering/mathematics background is beneficial
- Familiarity with Linux is an advantage
- Working through the OpenFOAM Linux Guide is strongly encouraged