heat mass transfer another promising methodology large eddy simulation les especially guise detached eddy simulation des combination rans turbulence modelling large eddy simulation approximations large number possible approximations fluid dynamic problems commonly used listed ''boussinesq approximation'' neglects variations density except calculate buoyancy forces often used free convection problems density changes small ''lubrication theory'' ''hele shaw flow'' exploits large aspect ratio domain show certain terms
Natural science Physics Fluid dynamics