Stephen A. Lawrence <sa...@pobox.com> wrote: If by "steam engine" you mean "steam locomotive engine", then they actually > incorporated steam driers specifically to dry the steam after it left the > boiler and, IIRC, before it entered the superheater. That's what at least > some of those funny domes on the tops of the old locomotives had inside > them. >
They did indeed! But the steam was reasonably dry without them. Steam locomotives worked without those superheaters. In some applications, especially slow-moving yard engines that stopped and started often, the super heaters would malfunction and explode. So they did not use them with small switching engines or mining engines. Those engines were less efficient because of this. On mainline engines there were two domes, by the way. The larger one was filled with sand, which they sometimes had to drop on wet or icy tracks to improve traction. Locomotives still use sand. The point of the discussion is that engineers (railroad and HVAC) know from steam -- to put it in Yiddish syntax. - Jed