EFFECT OF INFLOW CONDITIONS ON UNDER-EXPANDED SUPERSONIC JETS

Yıl 2012, Cilt: 4 Sayı: 1, 17 - 30, 01.03.2012

M.M. Ashraful Alam Toshiaki Setoguchi

Öz

The present work involves numerical simulations to investigate the effect of inflow
condition on aerodynamic and shock characteristics of under-expanded turbulent jets
from sonic nozzle. The TVD finite volume method was carried out and two equation k-ε
turbulence model was used to model the turbulent stresses of the compressible flows in
the present simulations. The jet pressure ratio was settled from 1.893 to 6.0 for
generating perfectly expanded to moderately high under-expanded jets. The pressure and
Mach number distributions on jet axis, and the flowfield structure was visualized by
density distributions. The potential core and supersonic flow lengths were also
measured to make a quantitative investigation on the jet structure. The effect of inflow
condition at nozzle inlet was found to be pronounced resulting in the sonic line moved
upstream of the nozzle throat. Moreover, numerically predicted results were compared
with the experimental data to validate the present numerical code.

Anahtar Kelimeler

Compressible flow, numerical analysis, potential core, shock wave, supersonic flow lengths

Kaynakça

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