Modeling of supercritical fluid flow through a yarn package

Steady-state supercritical fluid flow through both isotropic and anisotropi c cylindrical yam packages is modeled as 2-D, axisymmetric flow through por ous media. A numerical flow model using a finite-difference method predicts pressure and velocity profiles based on user-defined package geometry, per meability profile, and fluid properties. The use of variable permeability i n the model allows simulation of typical package heterogeneities that resul t from radial variations and relatively denser edges usually associated wit h package winding. The numerical model is compared with results obtained fr om analytical expressions for radial flow, axial flow, and 2-D flow in an a nnulus of isotropic, porous material. The model is then verified using expe rimental pressure drop measurements for a range of supercritical CO, flows through polyester yam packages. Model predictions show very good agreement with experimental data. (C) 2000 Elsevier Science B.V. All rights reserved.