Session: 04-21 Combustor Design III

Paper Number: 127693

127693 - Experimental Evaluation of Combustor Configuration's Impact on a Swirl-Assisted Jet-Stabilized Combustor Performance 

A major challenge for gas turbine combustor technology is the emission of NOx and CO. Achieving an optimal premixed, pre-vaporized, dry low-NOx condition is a critical issue for liquid fuel combustors. To accomplish this, the relationship between combustor configuration and the performance of a newly developed swirl-assisted jet-stabilized combustor is investigated in an atmospheric combustion facility. The combustor consists of a pressure-swirl fuel atomizer, a prefilmer/mixing channel, an axial moderate swirler (swirl number = 0.6), and a jet nozzle. The jet nozzle allowed for bulk velocities of 50-130 m/s. The influence of each combustor component on combustion performance and fuel evaporation behavior is evaluated independently using optical and laser combustion diagnostics. In addition to air and flame temperatures, the liquid fuel temperature was varied to allow for enhanced fuel evaporation through superheated injection. Jet A-1 was injected coaxially into the air stream under both liquid and superheated conditions. During the experiments, five critical combustor components were varied to understand their individual effect on fuel vaporization and thus combustion performance. Exhaust gas emissions of NOx, CO and UHC as well as OH* chemiluminescence images were used to evaluate combustor performance and were measured for all configuration variations. Mie scattering technique was used to analyze the degree of liquid fuel evaporation for different test cases. It was found that the combustion performance indicators CO, height above burner and flame length were well controlled by the degree of fuel evaporation, while NOx emissions showed little change with different combustor configurations. While the main factor influencing the level of NOx emissions was the temperature of the flame, the quality of fuel evaporation played a minor role. It was found that the operating range of the combustor and the geometric shape of the flame are significantly influenced by the components of the combustor.

Presenting Author: Peter Kutne German Aerospace Center (DLR), Institute of Combustion Technology

Presenting Author Biography: Peter Kutne holds a PhD in physical chemistry from the University of Göttingen (Germany), and started his career at the Max-Planck Institute for Biophysical Chemistry. In 2004 he joined the DLR Institute of Combustion Technology in Stuttgart, where he investigated pressurized combustion and developed combustion systems for different gas turbine applications. Since 2017 he became head of the Department “Gas Turbines” of the Institute, focusing on the optimization and development of micro gas turbine systems. He is member of the biomass panel of the European Technology an Innovation Platform “Renewable heating and cooling”. In the European Turbine Network he is chairperson of the hydrogen working group and member of the project board.

Authors:

Saeed Izadi German Aerospace Center (DLR), Institute of Combustion Technology
Jan Zanger German Aerospace Center (DLR), Institute of Combustion Technology
Hannah Seliger-Ost German Aerospace Center (DLR), Institute of Combustion Technology
Peter Kutne German Aerospace Center (DLR), Institute of Combustion Technology
Manfred Aigner German Aerospace Center (DLR), Institute of Combustion Technology