Evaluation of a flamelet/progress variable approach for pulverized coal combustion in a turbulent mixing layer |
| |
Authors: | Martin Rieth Andreas M. Kempf Oliver T. Stein Andreas Kronenburg Christian Hasse Michele Vascellari |
| |
Affiliation: | 1. Institute for Combustion and Gasdynamics (IVG), Chair for Fluid Dynamics, University of Duisburg-Essen, Carl-Benz-Str. 199, Duisburg 47057, Germany;2. Institut für Technische Verbrennung, Universität Stuttgart, Herdweg 51, Stuttgart 70174, Germany;3. Simulation of Reactive Thermo-Fluid Systems, TU Darmstadt, Otto-Berndt-Straße 2, Darmstadt 64827, Germany;4. Numerical Thermo-Fluid Dynamics, TU Bergakademie Freiberg, Fuchsmühlenweg 9, Freiberg 09599, Germany |
| |
Abstract: | A steady flamelet/progress variable (FPV) approach for pulverized coal flames is employed to simulate coal particle burning in a turbulent shear and mixing layer. The configuration consists of a carrier-gas stream of air laden with coal particles that mixes with an oxidizer stream of hot products from lean combustion. Carrier-phase DNS (CP-DNS) are performed, where the turbulent flow field is fully resolved, whereas the coal is represented by Lagrangian point particles. CP-DNS with direct chemistry integration is performed first and provides state-of-the-art validation data for FPV modeling. In a second step the control variables for FPV are extracted from the CP-DNS and used to test if the tabulated manifold can correctly describe the reacting flow (a priorianalysis). Finally a fully coupled a posteriori FPV simulation is performed, where only the FPV control variables are transported, and the chemical state is retrieved from the table and fed back to the flow solver. The a priori results show that the FPV approach is suitable for modeling the complex reacting multiphase flow considered here. The a posteriori data is similarly in good agreement with the reference CP-DNS, although stronger deviations than a priori can be observed. These discrepancies mainly appear in the upper flame (of the present DNS), where premixing and highly unsteady extinction and re-ignition effects play a role, which are difficult to capture by steady non-premixed FPV modeling. However, the present FPV model accurately captures the lower, more stable flame that burns in non-premixed mode. |
| |
Keywords: | Flamelet Carrier-phase DNS FPV Turbulent mixing layer Pulverized coal combustion |
本文献已被 ScienceDirect 等数据库收录! |
|