Ignition and Flame Speed Characteristics of H2/Air/Exhaust Gas Mixtures

Michigan State University, East Lansing MI

Investigators

Abstract

Growing concerns over global warming have led to an increased focus on carbon-free power cycles. Hydrogen is a promising alternative to conventional ground-based power gas turbine fuels, such as natural gas, due to its high calorific value and it is also carbon neutral and can be generated from renewable energy sources. Therefore, the gas turbine industry has committed to achieve a carbon neutral energy system using 100% hydrogen firing by 2030. However, hydrogen is very reactive relative to natural gas resulting in high flame speeds which can lead to an increased risk of the flame moving upstream and causing instabilities, such as flashback, within the burner. Consequently, it is important to understand the flame reactivity, flame stability, and combustion stability of hydrogen flames. The overall goal of this project is to advance the understanding of hydrogen combustion and flame characteristics in order to achieve safe, stable, carbon free, and efficient combustion. Successful completion of the project will benefit society by increasing our understanding of dilute hydrogen combustion in gas turbine combustors and other hydrogen combustion applications, such as internal combustion engines, and their potential for integration into our energy infrastructure. The project will further benefit society by introducing the next generation of engineers to engineering research concepts in the areas of energy and combustion through Michigan State University (MSU)’s K-12 outreach programs, including MSU Girl’s STEM Day and MSU engineering summer camps for under-represented groups in science and engineering. Major initiatives are underway in the United States to improve combustion efficiency and reduce emissions. These initiatives are primarily focused on the energy and transportation sectors, and often seek to replace conventional fuels with alternative carbon neutral or carbon free fuels. Current research is focused on advanced gas turbine combustors and engines that operate highly diluted on hydrogen/air/exhaust gas mixtures as this provides a means to reduce oxide of nitrogen and carbon monoxide emissions while maintaining fuel efficiency. This project will investigate the ignition and combustion chemical kinetics of hydrogen/air/exhaust gas mixtures in a rapid compression machine. In addition, laminar flame speeds and Markstein lengths of the mixtures will be measured in a constant volume combustion vessel. The autoignition and laminar flame speed experiments will enable an increased understanding of hydrogen/air/exhaust gas combustion that will contribute to safe, carbon free, and efficient hydrogen fuel operation for a cleaner environment. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.