Numerical simulation of pressure-driven startup laminar flows through a planar T-junction channel

A start-up flow of a viscous incompressible fluid in a T-junction channel is studied numerically. The flow starting from rest is driven by a constant pressure drops suddenly applied between the entries and exits of a planar T-junction channel. The Navier–Stokes equations in primitive variables are solved numerically using finite-volume techniques. Predicted variations with time of the volume flow rates and the flow patterns are presented for several values of pressure drops. It has been shown that a start-up flow can pass through different regimes (or different flow direction) before asymptotically reaching steady state distribution.

► Start-up flow in a planar T-junction channel is studied.
► Flow starting from rest and driving by pressure drops between the entries and exits.
► Volume flow rates are unknown a priori and are an outcome of numerical solution.
► Start-up flow can pass through different regimes before reaching steady state.