A trip time model for traffic flow on a semi-closed loop

A whole link model of traffic flow in which the link trip time varies linearly with link volume is investigated in the case where a fraction of the flow exiting the link is ‘re-injected’ as inflow, thus forming the link into a looped link. Scenarios are considered where the fraction of flow re-injected is held constant, and where it varies as a function of link volume. The model is solved completely in the case of a constant inflow, with constant fractional re-injection, and an algorithm for dealing with general inflows is stated. Numerical solutions for a selection of inflow profiles are presented and discussed.