Airflow in a slot-ventilated enclosure partially filled with porous boxes: Part II – Measurements and simulations within porous boxes

Abstract The present study will give rise to better understanding of the airflow behaviour in a ceiling-slot ventilated enclosure partially filled with slotted porous boxes under isothermal conditions. Boxes were filled randomly with spheres of the same diameter. Laser Doppler velocimetry (LDV) measurements and computational fluid dynamics (CFD) predictions were carried out to characterize air velocity inside packed vented boxes. An original approach was also developed to evaluate the internal macroscopic velocities within the boxes by means of thermal sphere-shaped probes. LDV measurements and CFD predictions related to the main turbulent flow developed by the jet above the boxes were presented in the part I. Special attention was paid to the strong aerodynamic interactions observed on the top faces of the slotted boxes, between the external main flow and the return flow which predominate inside the boxes. Numerical and experimental data make it possible to evaluate the air ventilation levels and their heterogeneity for the different boxes. The RSM turbulence model gives reasonable agreement with experiments.

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