## 1 Introduction
The authors found that an augmentation in the dimensions of the cyclone inlets resulted in an attenuation in its performance. Additionally, the literature portrays research referring to the effects that the conical section has on the performance of the cyclone separator. To that effect, [PERSON] et al. [16] simulated the performance of three cyclones using CFD, each cyclone with different diameters in the bottom of the cone. The simulations revealed that a decrease of size to the lower diameter of the conical section resulted in an increase in the separation efficiency and the pressure drop. Interestingly, the aforementioned study could contradict the work presented by [PERSON] and [PERSON] [20], who researched the effect that the diameter of the bottom of the cone has on the performance of three cyclone separators. The authors concluded that the diameter of the tip of the cone has an insignificant effect on the performance of the cyclone. However, [PERSON] et al. [21] determined that the size of the cone has a significant effect on the performance of the cyclone if its opening is greater compared to the diameter of the vortex finder. In terms of the vortex finder, the literature exposes certain differences that have had effects on the geometry of the exit duct. Regarding this aspect, [PERSON] [22] conducted an experiment using cyclones with smaller diameters in their vortex finder. The author found that the cyclones with less small diameter in their vortex finder conveyed a cutback in the cyclone's central vortex, as well as a boost in the separation efficiency. Additionally, the research objective of [PERSON] [23] was to optimize the dimensions of the vortex finder. Five models of cyclone separators were tested in the study; each model had a unique geometrical configuration in its vortex finder. Results established that an increase in the diameter of the exit duct causes reductions in efficiency and in the pressure drop. Moreover, [PERSON] and [PERSON] [24] and [PERSON] et al. [14] have validated the impact of the diameter of the vortex finder. The authors found the relationship between the diameter of the vortex finder and the efficiency parameters of the cyclone. If this is the case, a reduction in the diameter of the exit duct leads to increments in the efficiency of separation and pressure drop of the cyclone concurrently. In reference to the background previously stated, it is possible to conceive part of the progress developed during the last few years in order to continually improve the characteristics of the equipment. However, despite all this progress, there are many avenues of improvement that can be applied to these devices that have not been examined as of today. One of these possibilities is the use of passive flow control techniques, like the ones proposed in [25; 26; 27; 28; 29; 30; 31; 32; 33; 34; 35]. The contribution of this research is framed in the use of Computational Fluid Dynamics (CFD) to describe a new cyclone separator model with geometrical changes based on passive flow control techniques. To do so, three geometrical models were built, for which, their separation efficiency and pressure drop will be determined and evaluated to establish the new cyclone model.