Reducing air consumption has become the direction of improvement for vortex spinning technology which is most suitable for producing fasciated viscose yarns at high speed. In this article, computational fluid dynamics (CFD) models are established to study the effects of some injector parameters of the nozzle on the air consumption and yarn properties of vortex spinning for producing viscose yarns. Based on the model, the airflow pattern, including the static pressure and velocity characteristics as well as the mechanical energy distribution of the airflow in the nozzle are analyzed, while the air consumption and fiber motional characteristics during the yarn formation process are predicted. The experimental measurements of the air flow rate and yarn tenacity are also conducted to verify the numerical results. The results show that the air consumption increases monotonically as the diameter of injectors (d) increases from 0.4 to 0.6 mm, while it decreases as the radial distance from the injector axis to the nozzle axis ( R ¯ ) varies from 0 to 1. The yarn tenacity first increases as d increases from 0.4 to 0.5 mm, and then exhibits a decreasing trend as d further increases from 0.5 to 0.6 mm. Moreover, the yarn tenacity generally exhibits insignificant differences as R ¯ increases from 0 to 0.5, while it decreases more obviously as R ¯ increases from 0.5 to 1. This work can provide a reference for the design of the energy-efficient nozzle of vortex spinning for producing viscose yarns.