Dependence of Pressure Field in Vortex Tube on Cold Orifice Plate Diameter: A Simulation Study

The pressure field of pure CO₂ in vortex tube was mathematically formulated with Standard k-ε turbulence model, theoretically analyzed and numerically simulated with CFD software. The influence of the cold orifice-plate diameter on the pressure field was investigated. The simulated results show that the diameter has a major impact. For example, at a cold flow-rate of 0. 1, as the diameter increases from 1. 5 to 3. 5 mm, the axial pressure profile changes in a decrease-increase mode, accompanied by an increasing radial pressure distribution at Z=0.In0. 5~1. 0 mm range of R, as Z (axial-distance) increases, the axial pressure increases, but at R=1. 5 mm, the axial pressure changes in an increase-decrease manner with an increasing Z; in 2. 0~2. 5 mm range, the axial pressure decreases with an increasing Z. As Z increases from 0 to 100 mm, the radial pressure profile, at all Zs and increasing with an increasing R, changes in an increase-constant way.