Experimental study on cold flow characteristics of biomass hot water hot blast stove
The biomass hot water hot blast stove has the characteristics of stable and clean combustion, and has a simple structure and good load adaptability. The biomass granule furnace gas swirl burner is divided into two types: intake air and circumferential intake air, and the fuel is generally a single gas. . With the advancement of swirling combustion, gas swirl burners are developing in a direction suitable for mixed combustion of a plurality of combustible gases. In order to study the airflow characteristics of the new gas swirl burner, a test bench for a double swirl gas swirl burner was established. In this paper, the cold flow field is measured by two-dimensional hot wire anemometer, and the distribution law of aerodynamic field is obtained when different flares are installed in the burner exit, and the load on the burner is measured when the scale is expanded. Adaptability, in order to further understand the burner's stable burning characteristics when installing the scaling flare, providing detailed experimental data for the design of multi-component gas burners.
The effect of different flared structures on the turbulence intensity under the rated load of the biomass hot water hot blast stove is shown in Fig. 7. After the flaring is removed, the turbulence intensity is higher than the case where the scaled flare is installed, but in the recirculation zone, the attenuation is severe. After the installation of the tapered flaring, the turbulence intensity is lower near the outlet of the biomass burner, and at a farther distance from the outlet (Y>2.5), the overall level is higher than that of the installation of the scaled flaring. Mainly due to the fact that in the vicinity of the exit, the tangential velocity is relatively large. Although there is also fading/J but away from the exit, the tangential velocity still has a relatively high axial velocity, which makes the turbulence intensity larger, which is conducive to the mixing between the airflows. And the burning of fuel. After the tapered flaring is installed, the value of the turbulent intensity of the exit flow field of the biomass burner does not appear in the recirculation zone, but increases suddenly after the gas is far from the recirculation zone. This is mainly because the recirculation zone is small and the reflux velocity value is also low.