Multi-Dimensional Flamelet Modelling for the LES of Pulverised Coal Flames
Final Report Abstract
This project was targeted at the development, validation and application of flamelet models for the accurate and efficient modeling of pulverized coal combustion (PCC) for large eddy simulation (LES). The focus of project phase 1 was the demonstration of the general suitability of the flamelet method for modeling PCC. Phase 2 targeted the subjects of flue gas recirculation (FGR) and pollutant formation from PCC in the flamelet context. The project was a collaborative effort of TU Darmstadt (DA), the University of Stuttgart (ST) and the University of Duisburg-Essen (DE). The major project achievements from phase 2 are summarized as follows. The DA group accomplished the (i) consideration of strong heat losses and multi-mode combustion in flamelet models for PCC, (ii) evaluation of progress variable definitions suitable for PCC, (iii) development and validation of flamelet models for detailed NOx/SOx predictions and (iv) development and analysis of flamelet models for PCC with FGR. The major achievements of the ST group were (i) fully-resolved DNS analyses and characterizations of single particle and particle group combustion, (ii) high-fidelity fully-resolved and Euler-Lagrange DNS approaches using the generalized, fuel-flexible PoliMi approach, (iii) detailed CP-DNS analyses of the complete NOx formation pathways from fuel-bound nitrogen and (iv) CP-DNS predictions and analyses of PCC in FGR environments. The DE group achieved the (i) development of a suitable model representation for experimental suction probes in PCC experiments, (ii) development and validation of reliable homogeneous chemistry for coal/ammonia co-firing, (iii) highly-resolved LES of coal, ammonia and coal/ammonia co-firing with detailed NOx predictions and (iv) flamelet-LES predictions of PCC with FGR and pollutant formation in a highly-turbulent realistic swirl burner configuration. The joint achievements by all three groups were (i) the establishment of multistream flamelet/progress variable (FPV) modeling as a suitable approach for detailed pollutant predictions from PCC, (ii) archival confirmation that multi-stream FPV can be used to reliably predict PCC flames with FGR and (iii) the continued regular operation of the CBC Workshop as an international forum on measurement and simulation of solid fuel combustion.
Publications
- “A comprehensive study of flamelet tabulation methods for pulverized coal combustion in a turbulent mixing layer - Part II: strong heat losses and multi-mode combustion”, Combust. Flame 216:453-467 (2020)
X. Wen, M. Rieth, A. Scholtissek, O.T. Stein, H. Wang, K. Luo, A.M. Kempf, A. Kronenburg, J. Fan, C. Hasse
(See online at https://doi.org/10.1016/j.combustflame.2019.12.028) - “Carrier-phase DNS of detailed NOx formation in early-stage pulverized coal combustion with fuel-bound nitrogen”, Fuel 291:119998 (2021)
A. Shamooni, P. Debiagi, B. Wang, T.D. Luu, O.T. Stein, A. Kronenburg, G. Bagheri, A. Stagni, A. Frassoldati, T. Faravelli, A.M. Kempf, X. Wen, C. Hasse
(See online at https://doi.org/10.1016/j.fuel.2020.119998) - “Detailed analysis of early-stage NO formation in turbulent pulverized coal combustion with fuelbound nitrogen”, Proc. Combust. Inst. 38:4111-4119 (2021)
X. Wen, A. Shamooni, O.T. Stein, A. Kronenburg, L. Cai, H. Pitsch, A.M. Kempf, C. Hasse
(See online at https://doi.org/10.1016/j.proci.2020.06.317) - „Numerical analysis of a turbulent pulverized coal flame using a flamelet/progress variable approach and modeling experimental artifacts”, Energy & Fuels 35:7133-7143 (2021)
D. Meller, T. Lipkowicz, M. Rieth, O.T. Stein, A. Kronenburg, C. Hasse, A.M. Kempf
(See online at https://doi.org/10.1021/acs.energyfuels.0c03477)
