Accession Number : ADA132173

Title :   Effect of Shroud Geometry on the Effectiveness of a Short Mixing Stack Gas Eductor Model.

Descriptive Note : Master's thesis,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s) : Kavalis,Anastasios Emmanouil

Report Date : JUN 1983

Pagination or Media Count : 196

Abstract : An existing apparatus for testing models of gas educator systems using high temperature primary flow was modified to provide improved control and performance over a wide range of gas temperature and flow rates. Secondary flow pumping, temperature and pressure data were recorded for two gas educator system models. The first, previously tested under hot flow conditions, consists of a primary plate with four tilted-angled nozzles and a slotted, shrouded mixing stack with two diffuser rings (overall L/D = 1.5). The second consisted of the same nozzles and mixing stack, with a modified shroud and three diffuser rings (overall L/D = 1.5). A portable pyrometer with a surface probe was used for the second model in order to identify any hot spots at the external surface of the mixing stack, shroud and diffuser rings. The second model is shown to have almost the same mixing and pumping performance with the first one but to exhibit much lower shroud and diffuser surface temperatures.

Descriptors :   *Exhaust gases, *Temperature measuring instruments, *Nozzle gas flow, *Exhaust diffusers, *Shroud rings, Probes, Secondary flow, Jet mixing flow, Rings, Air flow, High temperature, Exits, Mixing, Pumping, Pyrometers, Flowmeters, Flow rate, Slots, Gas turbines, Marine engines, Hot spots, Surface temperature, Cooling, Theses

Subject Categories : Test Facilities, Equipment and Methods
      Fluid Mechanics
      Jet and Gas Turbine Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE