Study of the Possibility of Achieving the Same Per-Port Outflow in a Dividing Manifold

Abstract

There have been several attempts to optimise fluid flow manifolds; these, however, have shown are limited and further investigation into the efficiency of these systems is needed. This work focuses on improving the distribution manifolds efficacy in outflow division, i.e. attaining the same flow rate per each exit port of the manifold. Water has been selected to be the working fluid. A numerical investigation utilising CFD (by ANSYS Fluent R16.2) analysis into two-dimensional, incompressible, and turbulent flow has been carried out to resolve the flow manifold problem using two turbulence modelling, Standard k-ε and RNG k-ε, approaches. Four values of flow rate have been considered, which are specified by the Reynolds numbers 101×103, 202×103, 303×103, and 404×103. These values correspond to the fluid inlet velocities 0.5, 1.0, 1.5, and 2.0 m/s, respectively. The manifold configuration is defined by the given area ratio (total cross-sectional area for laterals /header cross-sectional area). Three values of area ratio are considered; these are 0.703125, 0.84375, and 0.984375. The results indicate that the flow uniformity has a reverse proportional relationship with the fluid flow rate and area ratio for all manifold arrangements. However, there is no significant effect of the flow rate increase on flow mal-distribution. Also, the use of RNG k-ε model has shown higher values of the non-uniformity coefficient than those obtained by the Standard k-ε model. The outcomes of this analysis have been compared with experimental data and a good agreement among them has been found.