MODELING OF NONSTATIONARY CONVECTIVE FLOW IN A BUILDING MODEL UNDER DIFFERENT BOUNDARY CONDITIONS FOR TEMPERATURE
Keywords:
Mathematical modeling, natural convection, Rayleigh-Benard vortices, Prandtl number, OpenFOAM, buoyantPimpleFoamAbstract
Non-stationary convective heat transfer in an air-filled shallow room is studied numerically. When solving the equation for pressure, taking into account external body forces, for example, gravitational forces, using the usual zero gradient condition zeroGradient can lead to a non-zero flow through the boundary of the computational domain. And the use of the fixedFluxPressure boundary condition guarantees a zero mass flow through the boundary. Mathematical modeling of natural convection in a rectangular cavity with an aspect ratio of 0.5 was carried out within the framework of the OpenFOAM package using the buoyantPimpleFoam solver. Under different boundary conditions for temperature, the temperature field is different. In other words, the average temperature field is not self-similar - the temperature field depends on the temperature boundary conditions.
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