Published Papers
     Search Papers (Springer,
   After 2008)
     Search Papers (Dbpia,
   Until 2007)
     Search Papers (JMST
   own data base)
       - Classification By Year   
       - Classification By Topic
     Special Issues
   
           
   
 
 
Subject Keyword Abstract Author
 
 
Numerically analyzed supersonic flow structure behind the exit of a two-dimensional micro nozzle

Sungcho Kim
The Journal of Mechanical Science and Technology, vol. 22, no. 6, pp.1174-1180, 2008

Abstract : The compressible flow field is numerically analyzed in a two-dimensional converging-diverging nozzle of which the area ratio, exit to throat, is 1.8. The solver is FLUENT and the embedded RNG k −¥å model is adopted to simulate turbulent flow. The plume characteristics such as shock-cell structure are discussed when nozzle pressure ratio and stagnation temperature at the nozzle entrance are varied. The downstream flow field can be classified into two types based on the shock shapes generated near the nozzle exit. First, a reiterative pattern in the plume is not formed between the slip streams in case that a strong lambda-type shock wave exists. Second, when oblique shock waves are crossing each other on the nozzle centerline, a shock cell structure appears in the plume field. Even when the flow field is changed due to stagnation temperature, the upstream of the shock wave is little affected. Especially, the pressure distributions on the nozzle centerline behind the shock wave are rarely influenced by the stagnation temperature, that is, the product of density and temperature is nearly constant provided that the working fluid is a perfect gas. Therefore, the pressure field shows quasi-isobaric behavior far downstream.

Keyword : Nozzle pressure ratio (NPR); Plume structure; RNG k −¥å turbulence model; Shock cell; Mach reflection, Regular reflection

 
 
 
JMST Editorial Office: #702 KSTC New Bldg, 22 7-gil, Teheran-ro, Gangnam-gu, Seoul 06130, Korea
TEL: +82-2-501-3605, E-mail: editorial@j-mst.org
JMST Production Office: #702 KSTC New Bldg, 22 7-gil, Teheran-ro, Gangnam-gu, Seoul 06130, Korea
TEL: +82-2-501-6056, FAX: +82-2-501-3649, E-mail: editorial@j-mst.org