Study of the aerodynamic sealing of a cold store – Experimental and numerical approaches

An experimental study was conducted in a laboratory scale model in order to characterize the airflow generated by an air curtain device (ACD) on the aerodynamic sealing of refrigerated spaces. The laboratory scale model consists of two similar adjacent rooms connected by a door over which the ACD device was installed. The tracer gas technique was used to calculate the sealing effect achieved with the air curtain at different jet velocities.A three-dimensional numerical model was also developed to simulate the heat and mass transfer phenomena, as well as the aerodynamic sealing performance of an ACD. The numerical study was carried out using a commercial CFD code (ANSYS-CFX®) and the turbulence effects were approached by two different turbulence models (k–ɛ and k–ω SST).The experimental and numerical results show a good agreement for validation purposes. No significant differences were found in the results obtained with the two turbulence models, although the k–ω SST model seems to be more appropriate for the simulations. The existence of an optimum discharge air jet velocity was confirmed. The results also indicate that the air curtain is more efficient in reducing the mass transfer than the energy flow rate across the doorway.

► The importance of identifying the uncertainties in the experiments was demonstrated.
► The CFD predictions show a good agreement with the experimental results.
► The k–ω SST turbulence model provided slightly better predictions than the k–ɛ model.
► The results show that the sealing efficiency can reach values above 75%.
► The ACD is more efficient in reducing mass flow than energy flow across the doorway.