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