A
set of five non-dimen
sional parameter
s wa
s developed to
scale the pre
ssure pul
se inten
sity in te
st rig
s for flat-
sheet
surface filter media. Four of the
se parameter
s link geometrical proportion
s of the clean ga
s section of the device, the media permeability, the ambient pre
ssure and the tank pre
ssure. The fifth parameter, related to valve opening time, i
s shown to be in
significant during practical operation. Experiment
s show that the
scaling law
s for the pre
ssure pul
se
signal are reflected accurately by thi
s set of non-dimen
sional parameter
s. The mea
surement
s were performed on a VDI type te
sting unit in variou
s combination
s of geometrical and operating parameter
s and with three media permeabilitie
s.
The results imply that differences in regeneration pulse intensity between filter testers which differ substantially in any one or more geometric proportions, such as those according to the VDI and JIS norms, cannot be reconciled by adjusting the tank pressure to a definite value.