| Title |
Numerical Study on the Turbulent Flow in the 180° Bends Decreasing Cross-sectional Aspect Ratio |
| Keywords |
Duct flow ; 덕트유동 ; Reynolds stress ; 레이놀즈 응력 ; Turbulence model ; 난류모형 ; Covariant velocity component ; 반변속도성분 |
| Abstract |
This paper reports the characteristics of the three dimensional turbulent flow in the 180 degree bends with decreasing cross-sectional area by numerical method. Calculated pressure and velocity, Reynolds stress distributions are compared to the experimental data. Turbulence model employed are low Reynolds number k-epsilon model and algebraic stress model. The results show that the main vortex generated from the inlet part of the bend maintained to outlet of the bend because of the contraction of cross-sectional area. The rate of increase of turbulent kinetic energy through the bend are lower than that of mean flow. Secondary flow strength of the flow is lower about 60% than that of square duct flow. |