ISSN Online: 2377-424X
ISBN Print: 0-85295-345-3
International Heat Transfer Conference 10
Application of the Multiple-Time-Scale Turbulence Model to the Prediction of 2-D Film Cooling Effectiveness
要約
The paper presents a 2-D computation of film
cooling effectiveness using the multiple-time-scale
(M-T-S) turbulence model. The objective of
the present study is to improve the prediction of
the effectiveness at high mass flow ratios when
the inequilibrium of the turbulence is
significant. The M-T-S turbulence model by Kim
and Chen (1989) is used to model the turbulence
and the governing equations are solved by an
elliptic solver with multi-grid enhancement. The
near-wall turbulence is modelled using a low-Re
k model with a refined grid. Computations are
carried out at mass flow ratios of RM = 0.2, O. 4, O. 6. Comparison between computations and measurements shows that the M-T-S model gives overall better prediction of effectiveness than the k-ε model especially in the
recovery region downstream of the separation
bubble. Comparison between the computed and
measured velocity profiles also shows good
agreement. However, the results suggest that the
treatment of near-wall turbulence in the
separation bubble fails to account for the
increased mixing in the region of separation and
reattachment.