Predictions of swirling flow in sudden‐expansion dump combustor with flameholder side‐inlet using two‐step combustion model

The swirling flow of sudden‐expansion dump combustor with central V‐gutter flameholder and six side‐inlets is studied by employing the SIMPLE‐C algorithm and Jones‐Launder k‐ε two‐equation turbulent model. Both combustion models of one‐step with infinite chemical reaction rate and two‐step with finite chemical reaction rate of eddy‐breakup (EBU) model are used to solve the present problem. The results agreed well with available prediction data in terms of axial‐velocity and total pressure coefficient along combustor centerline. The flowfield structure of combustor considered is strongly affected by swirling, flameholder and side‐inlet flow. For the fixed strength of swirling, the length of central recirculation zone is decreased when the angle of V‐gutter is increased. The outlet velocity of combustor in reacting flow is higher than that in cold flow because the released heat of combustion causes the decrease of density throughout the combustor flowfield. The distribution of mass fraction of various species in reacting process depends on the mixing effect, chemical kinetic and the geometric configuration of combustor.