Session: 04-19 Combustor Design I

Paper Number: 122386

122386 - Improving Micro-Mixing Combustion Stability Using Fuel Preheating and Product Recirculation 

Micro-mixing is a promising combustion approach due to its inherent safety against flashback and autoignition, with multiple studies having demonstrated low NOx levels in the order of premixed combustion. Previous work has extended the operating limits of micro-mixing combustion to the design requirements of highly recuperated gas turbines, demonstrating low NOx performance at inlet temperatures of up to ~1000 K with hydrogen and hydrocarbon-based fuels such as propane, natural gas, and jet fuel. Due to its highly reactive nature, micro-mixing combustion of hydrogen is very stable, but instabilities were observed with hydrocarbon-based fuels when operating near premixed-levels of NOx due to their slower reaction rates, indicating that a trade-off exists between NOx emissions and combustion stability. This paper presents the experimental results of a new micro-mixing injector designed to improve combustion stability by 1) increasing the recirculation of combustion products to the flame zone, and 2) preheating the fuel by heat transfer from the combustion products to the injector. Although this configuration is still susceptible to instabilities, their amplitudes are much lower, with levels of <10 dB compared to ~20 dB for the standard micro-mixing injector. NOx emissions are similar for both injector configurations, indicating a better trade-off between combustion stability and emissions when operating near the levels of perfectly premixed combustion for the new injector configuration.

Presenting Author: Alexandre Landry-Blais Universit&#233; de Sherbrooke

Presenting Author Biography: Alexandre Landry-Blais is a PhD candidate in the Createk Design Lab of the University of Sherbrooke, working on the combustion system for the novel Inside-Out Ceramic Turbine (ICT). Previously, he has worked as a test engineer for Westport in Vancouver, Canada, and as a research engineer at the University of Sherbrooke. His fields of expertise are design, thermodynamics and engine testing.

Authors:

Alexandre Landry-Blais Université de Sherbrooke
Xavier Bellavance Université de Sherbrooke
Mathilde Dehue Université de Sherbrooke
Jean-Sébastien Plante Université de Sherbrooke
Mathieu Picard Université de Sherbrooke