Study on the mixing characteristics of circular transverse jet in crossflow

2021 ◽  
Vol 112 ◽  
pp. 106599
Author(s):  
Ziwan Li ◽  
Yixiang Yuan ◽  
V.L. Varsegov ◽  
Baoting Guo ◽  
Bo Xiao ◽  
...  
2018 ◽  
Vol 55 (3) ◽  
pp. 733-751 ◽  
Author(s):  
Dickson Bwana Mosiria ◽  
Rong Fung Huang ◽  
Ching Min Hsu

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3224
Author(s):  
Ziwan Li ◽  
Yixiang Yuan ◽  
Baoting Guo ◽  
V. L. Varsegov ◽  
Jun Yao

Transverse jets in crossflow are widely used in energy systems, especially as dilution air jets, fuel/air mixers, and combustion equipment, and have received extensive attention and plenty of research. However, the studies of the circular transverse jet issued from a circular gap at the circumferential direction of a tube in crossflow are very limited. This paper studies a relatively new jet: the circular transverse jet. Firstly, numerical calculations are conducted under different turbulence models but with the same boundary conditions. By comparing the numerical results of different turbulence models with the existing experimental data, the turbulence model which is most suitable for the numerical calculation of the circular transverse jet is selected. Then, this turbulence model is used to calculate and analyze the flow field structure and its characteristics. It is found that due to the aerodynamic barrier effect of the high-velocity jet, a negative pressure zone is formed behind the jet trajectory; the existence of the negative pressure zone causes the formation of a vortex structure and a recirculation zone downstream the circular transverse jet; and the length/width ratio of the recirculation zone does not change with the changes of the crossflow and the jet parameters. It means that the recirculation zone is a fixed shape for a definite device. This would be fundamental references for the studying of fuel/air mixing characteristics and combustion efficiency when the circular transverse jet is used as a fuel/air mixer and stable combustion system.


2021 ◽  
Author(s):  
Ruben Bruno Diaz ◽  
Fabiola Paula Costa ◽  
Pedro M. Milani ◽  
Jesuino Takachi Tomita ◽  
Cleverson Bringhenti

2013 ◽  
Vol 30 (1) ◽  
pp. 87-96 ◽  
Author(s):  
C. M. Hsu ◽  
R. F. Huang

ABSTRACTThe influences of acoustic excitation on the velocity field and mixing characteristic of a jet in cross-flow were investigated in a wind tunnel. The acoustic excitation waves at resonance Strouhal number were generated by a loudspeaker. The time-averaged velocity field and streamlines of the excited elevated transverse jet in the symmetry plane were measured by a high-speed particle image velocimetry. The visual penetration height and spread width were obtained by using an image processing technique. The dispersion characteristics were obtained from the tracer-gas concentration measurement. The results showed that the streamline pattern of the non-excited transverse jet was significantly modified by the acoustic excitation—the bent streamlines evolved from the jet exit escalated and the vortex rings in the jet and tube wakes and the recirculation bubble in the jet wake disappeared. The time-averaged velocity distributions revealed that the excited transverse jet produces large momentum in the up-shooting direction so that the velocity trajectories were located at levels higher than those of the non-excited one. The mixing characteristics, which include the visual penetration height, spread width, and dispersion, were drastically improved by the acoustic excitation due to the changes in the flow structures. The excited transverse jet characterized at larger jet-to-crossflow momentum flux ratios presented larger improvement in the mixing characteristics than at lower jet-to-crossflow momentum flux ratios.


2013 ◽  
Vol 5 ◽  
pp. 762595 ◽  
Author(s):  
Jinshui Wu ◽  
Hongbo Wang ◽  
Mingbo Sun ◽  
Shunpin Zhang ◽  
Zhenguo Wang

Sign in / Sign up

Export Citation Format

Share Document