#history of the #steam-engine and #Drebbel, Bacon, Kaspar Kalthoff, water pumping, etc.
on 02022-10-14countercurrent #heat-exchangers called recuperators are commonly used to recover 70-80% of the exhaust heat to preheat incoming air and fuel in metallurgical furnaces, heat engines including microturbines, and also in #Gelbart’s uniflow #steam-engine. #mecheng
on 02015-08-14A #refractory #ceramic (1850° or so), typically sintered with spark plasma sintering. Gelbart’s #steam-engine uses it for the intake valve because it's more resistant to being pitted by the steam than steel is. #materials
on 02015-08-13Dan #Gelbart’s description of his 2010 #steam-engine. (Or maybe it's Tom Kimmel’s.) Includes a sort of zero-#TCE construction to keep the inside diameter of the cylinder constant: when the 440C stainless-steel cylinder expands, the graphite-filled #polyimide (Vespel) liner tries to expand even more, but can only do so toward the inside of the cylinder, thus counteracting the cylinder’s expansion. The piston itself is made of electroless-nickel-plated #Invar, which really seems like overkill, but whatever. The tabletop model reaches 10% efficiency.
on 02015-08-13#Video of Dan #Gelbart's uniflow #steam-engine #engineering #hardware
on 02015-08-13