A decomposition approximation for finite-buffered flow lines of exponential queues

Tandem queueing networks may be used as an alternative to simulation in evaluating the performance of proposed flow lines with finite work-in-process buffers. A new approximation is proposed for estimating the throughput rate and work-in-process inventory of finite-buffered exponential queues in series. The approximation is applied to several sets of previously published test problems and is shown to consistently perform well relative to existing models. In addition, a large simulation experiment is conducted to examine the robustness of the approximation under a wide range of parameter settings.