{HEAD ~ The upper portion} of {TAIL ~ housing} 4 contains the aforementioned impeller 6 immersed in a viscous fluid 18, the fluid completely fills the upper portion of housing 4 
of
{ HEAD ~ The upper portion } of { TAIL ~ housing } 4 contains the aforementioned impeller 6 immersed in a viscous fluid 18 , the fluid completely fills the upper portion of housing 4
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL 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 OTH OTH OTH