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The weeping phenomenon was investigated using some experimental tests and a numerical model. The tests were performed within a 1.22‐m‐diameter pilot‐scale column including two chimney trays and two Nye test trays with an air‐water system. The rates of weeping were measured in the Nye trays with two heights of the weir and a hole area of 5 %. Moreover, the weeping rates in the outlet and inlet halves of the Nye tray and the total weeping rate were calculated. In the next step, an Eulerian‐Eulerian computational fluid dynamics (CFD) technique was used. The results show good agreement between the attained CFD findings and the experimental data.

Nye and sieve trays were hydrodynamically simulated and compared. The simulations were performed in a Eulerian-Eulerian framework under unsteady (transient) conditions at industrial scale. Conducted on an air-water system, the simulations included three dimensions and two phases. The velocity distribution across the tray, the height of clear liquid, the froth height, and the pressure drop were investigated and compared with experimental data. Péclet number was calculated using hydrodynamic and geometric parameters. The tray efficiencies were also predicted to further compare the two trays. The results showed that the liquid flow was steadier on the Nye tray rather than the sieve tray, possibly because of the special structure of the liquid and gas inlets for the Nye tray.

The hydrodynamic parameters of a Nye tray were investigated by performing experiments in a tower with a diameter of 1.22 m. Air was used as the gas phase and water was used as the liquid phase. A number of parameters such as the dry pressure drop, the total pressure drop, the clear liquid height, the froth height, and the entrainment were measured. A tray stability factor was obtained using the amount of weeping, the clear liquid height, the dry pressure drop, and the Froude number. All experiments were repeated for the matching sieve tray under the same conditions. Ultimately, advantages and disadvantages were compared, and the results demonstrated that the Nye tray has a couple of advantages over the sieve tray, except that the sieve tray is slightly more stable.

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