High Momentum Jet Flames at Elevated Pressure: A — Experimental and Numerical Investigation for Different Fuels

Abstract

In this work, results of comprehensive high-pressure tests and numerical simulations of high momentum jet flames in an optically accessible combustion chamber are presented. A generic single nozzle burner was designed as a full-scale representation of one duct of a high temperature FLOX® gas turbine combustor with a model pilot burner supporting the main nozzle. As an advanced step of the FLOX® gas turbine combustor development process, tests and simulations of the entire burner system (consisting of a multi nozzle main stage plus a pilot stage) are complemented with this work on an unscaled single nozzle combustor, thus supporting the development and testing of sub concepts and components like the mixing section and dual-fuel injectors. These injectors incorporate a gaseous fuel stage and a spray atomizer for liquid fuels, both separately exchangeable for testing of different fuel placement concepts. The combustor was successfully operated at gas turbine relevant conditions with natural gas including a variation of the Wobbe index, and with light heating oil with and without water admixture. The presented work is the first of two contributions and covers the description of the experimental setup, an overview of the numerical methods, high-pressure test results for different fuels and variations of the operating conditions including exhaust gas measurements and basic optical diagnostic methods, together with CFD results for several cases. The other part will present detailed and focused investigations of few conditions by complex and extensive optical and laser combustion diagnostics.

High Momentum Jet Flames at Elevated Pressure: B — Detailed Investigation of Flame Stabilization With Simultaneous PIV and OH-LIF

“…A key feature of the test rig is a large optical access from all four sides, which allows for the extensive application of laser based and other optical diagnostic measurements. A detailed description of this test rig is given in the preceding paper [14] and in previous publications [8].…”

“…The flame could be monitored via several surveillance cameras and chemiluminescence cameras. With these basic measurements, the model burner was characterized in its whole operational range, and reference operation points could be identified [14] for more detailed measurements, which is the scope of this contribution.…”

“…At the beginning of the duct, the fuel (natural gas) is added to the air flow by the exchangeable fuel injector GAS1, 400 mm upstream of the burner base plate. This air guidance and mixing section is not shown here, but can be found in detail in Figure 1 of the preceding paper [14].…”

“…This setup of main and pilot burner is designed to recreate a sector of a full-scale gas turbine FLOX ® combustor (c.f. [14]).…”

“…These features are necessary for real scale chemistry. The motivation, design and characterization of this model burner, as well as the analysis of its load-and fuel-flexibility have been shown in the preceding ASME paper GT2017-64615 [14]. For the present study, two reference operation points for one injector/mixing configuration (CJ02GAS1) have been extracted from this basic characterization and investigated in detail with laser diagnostics, to gain insight into flame stabilization mechanisms.…”