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In this study, a suitable CFD (computational lfuid dynamics) model has been developed to investigate the inlfu-ence of liquid height on the discharge coefifcient of the oriifce-type liquid distributors. The oriifce lfow in different diam-eters and liquid heights has been realized using the shear stress transport (SST) turbulence model and the Gamma Theta transition (GTT) model. In the ANSYS CFX software, two models are used in conjunction with an automatic wall treatment which allows for a smooth shift from a wall function (WF) to a low turbulent-Re near wall formulation (LTRW). The results of the models coupled with LTRW are closer to the experimental results compared with the models with WF, indicating that LTRW is more appropriate for the prediction of boundary layer characteristics of oriifce lfow. Simulation results show that the lfow conditions of oriifces change with the variation of liquid height. With respect to the turbulence in oriifce, the SST model coupled with LTRW is recommended. However, with respect to the transition to turbulence in oriifce with an increase in liquid height, the predictions of GTT model coupled with LTRW are superior to those obtained using other models.