ab 0.75 Ratio a/b
ac 0.4[mm] Orifice center radius
tp 1[mm] Plate thickness
delta ac*(1-ab)/(1+ab) Radius shift
a ac-delta Orifice bottom radius
b ac+delta Orifice top radius
Lpml 0.5[mm] PML thickness
N0 50 Fillet fraction of radius
r0 ac/N0 Fillet radius
NH 25 Height geometry factor
NR 6 Radial geometry factor