Accumulator Tank: a sealed air chamber combined with a water reservoir provides expansion volume to reduce pump cycling from minor pressure changes and give a steady flow.

If the flame is propagating at steady speed in static and homogeneous clouds, flow field just behind the pressure waves is self-similar.

In steady flow rig the pressure drop and the mass flow rate of the DPF were measured, and the measured data are used in the estimation of DPF permeability.