A Giesl ejector is an exhaust installation for steam locomotives, which works on the jet pump principle.
The ejector - according to the outward appearance often called flat or chimney pejorative Quetschesse - 1951 developed by Dr. Adolph Giesl - Gieslingen. The Giesl ejector causes improved suction and therefore better energy utilization. The former is formed by a blowpipe blowpipe head with a plurality of successive blow pipe nozzles, the cone of rays overlap slightly. Thus, the diffuser gets its flat, elongated shape. A typical design of the ejector form seven standing in series blowpipe nozzle having an approximately square cross-section.
Giesl spoke of 6 to 12% savings in coal by the Giesl ejector, which were in practice more with a maximum of 8 %, and a power increase of up to 20%. It steam locomotives of many trains were rebuilt with Giesl ejectors, including at ÖBB, ČSD and DR, but also in railroads in Africa, China and Japan. Not in all cases, the license fees were paid, of which it was said that they would often almost offset the carbon savings. In the DR, the Giesl ejectors should have paid for itself after a year, which is why there over 500 locomotives were converted; mainly the series 38.10, 50, 52, 65.10 and 78 best-known single piece with Giesl ejector is the fast travel Versuchslok 18,201.
Apparently the German Federal Railroad was far less confident in their time of growth of the evaporation rate and improved cost-effectiveness by the Giesl ejector than the DR The conversion of the exhaust installation can be on typical flat chimney only recognize the 50 1503.