Delft-Jet-in-Hot-Coflow (DJHC) burner

Application Area 2: Combustion

Application Challenge AC2-11

Abstract

The Delft Jet-in-Hot-Coflow (DJHC) burner is a laboratory scale burner designed to mimic conditions found in relatively high-temperature combustion with low oxygen concentration oxidizers. The conditions are relevant to the study of the flameless combustion regime.

The DJHC was developed to investigate conditions usually associated with Flameless Combustion (term often replaced by or that shares similarities with MILD Combustion and Colourless-Distributed Combustion). The intention was to provide insights into the influence of operational conditions on the flame structure and to have experimental data that enables CFD validation.

The measurements performed at the Delft University of Technology included velocity field assessments with LDA (Laser Doppler Anemometry) and PIV (Particle Image Velocimetry) and temperature with CARS (Coherent Anti-Stokes Raman Spectroscopy), as well as OH concentration with LIF (Laser Induced Fluorescence). Experiments were run for a variety of operational conditions in relation to fuel jet Reynolds numbers, fuel composition, coflow composition and temperature.

This contribution to the Ercoftac Wiki makes available the measured inflow conditions and the LDA and CARS experimental data of local conditions in important regions of the flame for all studied cases. It also includes a detailed description and analysis of Computational Fluid Dynamics simulations for one of the flames (DJHC-I-Re4K5) with a variety of modelling approaches. In the CFD Simulations section, simulations performed with both RANS and LES methods are discussed, as well as three different turbulence-chemistry interaction models: Conditional Source-term Estimation (CSE), Eddy Dissipation Concept (EDC) and Flamelet Generated Manifolds (FGM). Best practice advice and recommendations for further investigations are given.

Contributed by: André Perpignan, Dirk Roekaerts, E. Oldenhof, E.H. van Veen, M.J. Tummers, Hesheng Bao, Xu Huang — TU Delft

Contributed by: Jeffrey W. Labahn — Stanford University