Author Contributions
Conceptualization, J.L. and H.L.; methodology, H.L.; software, H.L.; validation, Y.Z. and J.Y.; formal analysis, J.L.; investigation, Y.Z.; resources, J.Y.; data curation, J.L. and H.L.; writing—original draft preparation, J.L. and H.L.; writing—review and editing, H.L.; visualization, H.L.; supervision, J.L.; project administration, J.L.; funding acquisition, J.L. All authors have read and agreed to the published version of the manuscript.
Figure 1.
Schematic of the combustor geometry.
Figure 1.
Schematic of the combustor geometry.
Figure 2.
(a) Schematic diagram of the three-dimensional structure of the two-stage swirler; (b) the two-stage swirler used in the present experiments.
Figure 2.
(a) Schematic diagram of the three-dimensional structure of the two-stage swirler; (b) the two-stage swirler used in the present experiments.
Figure 3.
The flame of the burner in the furnace during the experiment.
Figure 3.
The flame of the burner in the furnace during the experiment.
Figure 4.
Overall grid diagram of burner numerical simulation area.
Figure 4.
Overall grid diagram of burner numerical simulation area.
Figure 5.
Three-dimensional structure of (a) D65-30 and (b) CD65-30.
Figure 5.
Three-dimensional structure of (a) D65-30 and (b) CD65-30.
Figure 6.
Axial velocity of D65-30 and CD65-30 at different axial positions.
Figure 6.
Axial velocity of D65-30 and CD65-30 at different axial positions.
Figure 7.
Tangential velocity of D65-30 and CD65-30 at different axial positions.
Figure 7.
Tangential velocity of D65-30 and CD65-30 at different axial positions.
Figure 8.
Temperature distribution of D65-30 and CD65-30 on the center cross section.
Figure 8.
Temperature distribution of D65-30 and CD65-30 on the center cross section.
Figure 9.
Temperature distribution of D65-30 and CD65-30 near the furnace wall.
Figure 9.
Temperature distribution of D65-30 and CD65-30 near the furnace wall.
Figure 10.
Local distribution of NOx concentration (ppm) of D65-30 and CD65-30 on the central cross section.
Figure 10.
Local distribution of NOx concentration (ppm) of D65-30 and CD65-30 on the central cross section.
Figure 11.
Three-dimensional diagram of different secondary-stage swirl blade angles.
Figure 11.
Three-dimensional diagram of different secondary-stage swirl blade angles.
Figure 12.
Axial velocity of CD65-30, CD55-30, and CD45-30 at different axial positions.
Figure 12.
Axial velocity of CD65-30, CD55-30, and CD45-30 at different axial positions.
Figure 13.
Tangential velocity of CD65-30, CD55-30, and CD45-30 at different axial positions.
Figure 13.
Tangential velocity of CD65-30, CD55-30, and CD45-30 at different axial positions.
Figure 14.
Temperature distribution of CD65-30, CD55-30, and CD45-30 in the center cross section.
Figure 14.
Temperature distribution of CD65-30, CD55-30, and CD45-30 in the center cross section.
Figure 15.
Temperature distribution of CD65-30, CD55-30, and CD45-30 near the furnace wall.
Figure 15.
Temperature distribution of CD65-30, CD55-30, and CD45-30 near the furnace wall.
Figure 16.
NOx local distribution of CD65-30, CD55-30, and CD45-30 on the central cross section.
Figure 16.
NOx local distribution of CD65-30, CD55-30, and CD45-30 on the central cross section.
Figure 17.
Three-dimensional structure of swirler with bluff structure.
Figure 17.
Three-dimensional structure of swirler with bluff structure.
Figure 18.
Axial velocity distribution of D65-C45, D65-C35, and D65-C25 at different axial positions.
Figure 18.
Axial velocity distribution of D65-C45, D65-C35, and D65-C25 at different axial positions.
Figure 19.
Tangential velocity distribution of D65-C45, D65-C35, and D65-C25 at different axial positions.
Figure 19.
Tangential velocity distribution of D65-C45, D65-C35, and D65-C25 at different axial positions.
Figure 20.
Temperature distribution of D65-C45, D65-C35, and D65-C25 in the center section.
Figure 20.
Temperature distribution of D65-C45, D65-C35, and D65-C25 in the center section.
Figure 21.
Temperature distribution of D65-C45, D65-C35, and D65-C25 near the furnace wall.
Figure 21.
Temperature distribution of D65-C45, D65-C35, and D65-C25 near the furnace wall.
Figure 22.
NOx local distribution of D65-C45, D65-35, and D65-C25 on the central cross section.
Figure 22.
NOx local distribution of D65-C45, D65-35, and D65-C25 on the central cross section.
Table 1.
Parameters for the combustor.
Table 1.
Parameters for the combustor.
Parameters | Values |
---|
Diameter of combustor exit (mm) | 830 |
Blade number of first stage blade | 28 |
Blade number of secondary stage blade | 30 |
Install angel of first stage blade (°) | 60 |
Install angel of secondary stage blade (°) | 65 |
Vane thickness (mm) | 1 |
Table 2.
Parameters for the experiments.
Table 2.
Parameters for the experiments.
Parameters | Values |
---|
Velocity of air inlet (m/s) | 18.92 |
Diameter of air inlet (m) | 0.35 |
Velocity of gas inlet (m/s) | 28 |
Diameter of gas inlet (m) | 0.141 |
Atmospheric temperature (K) | 298 |
Air inlet temperature (K) | 298 |
Excess air coefficient | 1.18 |
Outlet pressure (Pa) | −70 |
Table 3.
Comparison of experimental and numerical simulation results.
Table 3.
Comparison of experimental and numerical simulation results.
Thermocouple Number | Experiment | Simulation | Error |
---|
T1 | 798 °C | 827 °C | 3.6% |
T2 | 1092 °C | 998 °C | 8.6% |
T3 | 985 °C | 956 °C | 2.9% |
T4 | 967 °C | 1008 °C | 4.2% |
Table 4.
Average NOx concentration at the furnace exit for D65-30, CD65-30.
Table 4.
Average NOx concentration at the furnace exit for D65-30, CD65-30.
Name | NOx Concentration (ppm) |
---|
D65-30 | 70.8 |
CD65-30 | 57.3 |
Table 5.
Average NOx concentration at the furnace exit for CD65-30, CD55-30, and CD45-30.
Table 5.
Average NOx concentration at the furnace exit for CD65-30, CD55-30, and CD45-30.
Name | NOx Concentration (ppm) |
---|
CD65-30 | 57.3 |
CD55-30 | 76.2 |
CD45-30 | 84.6 |
Table 6.
Average NOx concentration at the furnace exit for D65-C45, D65-C35, and D65-C35.
Table 6.
Average NOx concentration at the furnace exit for D65-C45, D65-C35, and D65-C35.
Name | NOx Concentration (ppm) |
---|
D65-C45 | 64.9 |
D65-C35 | 58.4 |
D65-C25 | 57.9 |