Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN Print: 978-1-56700-474-8

ISBN Online: 978-1-56700-473-1

International Heat Transfer Conference 16
August, 10-15, 2018, Beijing, China

NUMERICAL ANALYSIS OF DUAL TWO-PHASE DISCHARGE FROM A HEADER

Get access (open in a dialog) DOI: 10.1615/IHTC16.mpf.022818
pages 6739-3746

Abstrakt

The main objective of this study was to assess the capability of a commercial CFD code in modelling two-phase flow from a header through two branches. The geometry considered in this study consists of a header with two horizontal outlet branches of the same diameter i>d = 6.35 mm, separated by a distance L center to center (L/d = 1.5) with their centerlines falling in a plane inclined an angle θ from the horizontal. Two values of θ were considered; θ = 30° and 90°. For each value of θ, the flow domain was divided into a large number of control volumes using a block-structured, hexahedral mesh. The inhomogeneous, free surface model of ANSYS CFX was used to model the flow throughout the flow domain. Mesh-independence tests were conducted and the solutions of the discretized equations were progressed in time using small time steps (≈1 × 10-4 s). Results were obtained for the critical heights of the interface at the onsets of gas and liquid entrainment at both branches, as well as the outlet mass flow rate and quality during two-phase discharge. For θ = 30°, good agreement was found between the numerical results and the available experimental data and correlations. For θ = 90° , the numerical model was able to predict results when there was two-phase flow in one branch and single-phase flow in the other branch; however, it did not converge with two-phase flow in both branches.