The results show that the gap size has obvious effect on the wall pressure upstream of the plate flap when it is greater than the height of the flap; and changes the wall pressure at 0≤g/h≤2.0 downstream of the plate flap, which is the recirculation region.
The results showed that the maximum of the turbulent energy in the recirculation region existed hysteresis,and the buoyancy affected the time averaged variables but had little effect on the turbulent ones.
In the paper,the experimental results of LYS 2P 10 liquefied petroleum gas flat flame burner are introduced,the diameter and thiokness of this burner studied,the maximum diameter and length of its backflow region discussed,and the distribution of negative pressue on center line of the backblow region experimented.
介绍了 L YS2 P- 10液化石油气平焰烧嘴的试验结果 ,研究了此烧嘴的平展形流股的直径和厚度 ,讨论了回流区的最大直径和长度 ,试验研究了回流区中心线上的负压分布
The k ε turbulent model, the three gase mixing combustion model and the composite radiosity model are used to simulate numerically the central backflow region of the turbulent diffusion flame in a gas burner with the PHOENICS software.
Abstract In order to improve combustion stability of low grade coal, the threedimensional velocity and turbulence distribution in the back flow region wasmeasured with a three dimensional LDA. Combustion tests were conducted in asingle nozzle test rig and actually applied in a 220t/h boiler firing low gradebituminous coal.
To improve the ability of in depth peak load cycling of a 200 MW boiler,according to the synthetic analysis on the results of investigation ,the technology of direct firing of adjustable coal powder gradation and the technology of adjustable scope of back flow region developed by Zhejiang University are used to modify the burners for stable combustion at low load.
Experimental study has been carried out on a cold model of a gas burner Using the APV system, the flow fields of the burner model have been measured The results show that there are two typical back flow regions in the burner Correlations between the dimensions of the main back flow region and the structure of the flame stabilizer were further studied The obtained correlations provide empirical principle and instruction for the design and evaluation of this type of gas burners
Incorporating the various effects, perpendicular injection shows the maximum mixing efficiency and its large upstream recirculation region has a good flame holding capability.
Based on the axial line velocity distribution, the flow after the disc can be divided into three regions, i.e., recirculation region, transitional region and self-similar region.
Planar laser-induced fluorescence (PLIF) imaging was performed to visualize the fin bow shock, separation shock, viscous shear layer and recirculation region of the flowfield at the junction of a blunt fin and a flat plate.
The results show that the outer secondary co-swirling jet significantly changes the structure of the inner under-expanded swirling jet, such as the shock structures and the recirculation region generated at the jet axis.
The results show that the recirculation region increases as the fuel injection pressure increases.
The experiment shows that after Transitory Detachment Reynolds shear stress is negative in the near-wall backflow region.
Finally, this method was successfully applied to confirm the existence of a small backflow region located in front of the large solitary waves, which were excited on the surface of a liquid film flowing down an inclined stationary plate.
A free molecule pressure probe2 is required to provide a better description of the flow pattern in the backflow region.
However, the absolute levels of the measured mass flux into the backflow region were very low, on the order of 7 x 10-7 g/cm2-sec or less.
However, the presence of a nonpumping surface in the backflow region appears to create a recirculatory flow field just ahead of it.