PhD Thesis Proposal Announcement

By

Henderson Johnson, II

(Advisor: Professor Tim C. Lieuwen)

Wednesday, November 14, 2018

Food Processing Building Auditorim

Turbulent Flame Speed Measurements of H2-Doped Methane Flames

Hydrogen is increasingly being incorporated into energy infrastructure as a means to allow for cleaner power generation. One particular example of this increased hydrogen addition can be seen in natural gas-fired gas turbines. Addition of hydrogen to natural gas increases its reactivity, and allows for increased flame stability at leaner conditions. Furthermore, in the development and design of gas turbines able to handle these hydrogen-doped natural gas fuel blends, it is important to consider how these fuel blends at relevant temperatures and pressures will impact gas turbine performance metrics, such as emissions and efficiency, and operability considerations, such as flame stability, thermal loadings and combustion instability limits. In attempting to capture these sensitivities, the turbulent flame speed, ST, is often studied to get a better understanding of these metrics.

The literature is rich with studies of the ST. However, the significant degree of interdependency of a variety of chemical and fluid mechanic parameters, have made it challenging to understand their impact on ST. This has made it increasingly challenging to develop robust computational models able to accurately predict flame location and propagation characteristics. Furthermore, this interdependency issue manifests in the literature where there are often times conflicting conclusions on the impact of key parameters on ST.

This study focuses on further clarifying the impact and interaction of pressure, temperature and fuel effects at gas turbine relevant conditions with the goal of developing a physics-based model able to capture the essential physics of ST.

            This proposal begins with a general overview of some of the turbulent flame speed work completed to date and details the challenges that have arisen in attempting to develop turbulent flame speed correlations. Next, I present a detailed look at the entirety of the Georgia Tech database and compare results between two different datasets.  These results include fuel blends containing various combinations of H2, CO­­, CH4 and N2 which can be used to simulate coal-derived fuels from various feedstocks. The results are then analyzed and set in the greater context of turbulent flame speed literature. Following the analysis is an overview of the proposed work which will focus on isolating impacts of various parameters and measurement methodologies on the turbulent flame speed. These results will then be used to develop physics-based correlations that capture the essential physics that drive the turbulent flame speed.

Professor Tim C. Lieuwen

Professor Jerry Seitzman

Professor Adam Steinberg