The cavity may include a plurality of {HEAD ~ pedestals} and protrusions configured to create one or more spirals flow {TAIL ~ paths} of a gas traveling through the cavity 
The cavity may include a plurality of { HEAD ~ pedestals } and protrusions configured to create one or more spirals flow { TAIL ~ paths } of a gas traveling through the cavity
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH