The aim of this work is to develop applicable methods to model wall inlets in numerical simulations of airflow in livestock buildings. Simulations were compared with measurements in an 8.5 m long, 3 m high and 10.14 m wide test room. A prefabricated wall inlet was centred 0.50 m beneath the ceiling and 5.87 m from one side wall of the room. The inlet was adjusted to supply 0.1 m 3 /s at a pressure difference of 10 Pa. Close to the inlet, air speed was significantly below the one predicted with a coarse orthogonal grid. Grid refinement in high velocity areas improved the agreement with measurements close to the inlet. But repeating refinements increased the number of cells so much, that the computer capacity limited the use of this technique. The construction of grids with cells orientated parallel to the inlet direction was more time consuming, but made it possible to obtain a fairly good agreement with measurements using relatively few cells. A complete geometric modelling of the inlet was even more time consuming, but increased the agreement with measurements and eliminated the need of measuring data to specify the inlet direction. Including the volume in front of the inlet gave small changes in the airflow pattern inside the room even though calm air flow conditions were assumed in front of the inlet.
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