Ignition and Flame Speed Characteristics of Hydrotreated Vegetable Oil/Air/Exhaust Gas Mixtures

Growing concerns over global warming have necessitated a reduction in greenhouse gas emissions and have led to an increased focus on biofuels. One promising second-generation biofuel that overcomes many of the hurdles associated with first-generation biofuels (cost, food competition, environmental impact, etc.) is hydrotreated vegetable oil. Hydrotreated vegetable oil can be produced from many plant-based oils such as soybean, sunflower, palm and even waste cooking oil and can be used directly as a drop-in replacement for diesel in engine applications. Drop-in hydrotreated vegetable oil can enable particulate, hydrocarbon and carbon monoxide emission reductions of near 50%. A more thorough understanding of fundamental combustion properties will enable improved numerical simulations of hydrotreated vegetable oil combustion in the engine design and optimization stage. It is important to understand the flame reactivity, flame stability, and combustion stability for hydrotreated vegetable oil/air flames. This project will also benefit society by introducing the next generation of engineers to engineering research concepts in the areas of energy and combustion through Michigan State University’s K-12 outreach programs, including Girl’s STEM Day and engineering summer camps for under-represented groups in science and engineering. The overall goal of this project is to advance the understanding of combustion and flame characteristics of hydrotreated vegetable oil/air/exhaust gas flames with an emphasis on conditions that occur in diesel engines. The proposed research will investigate the ignition and combustion chemical kinetics of hydrotreated vegetable oil/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 proposed autoignition and laminar flame speed experiments will enable an increased understanding of hydrotreated vegetable oil combustion that will contribute to safe and efficient hydrotreated vegetable oil operation for a cleaner environment. The educational plan will have broad impacts on teaching the next generation of engineers through three main activities including (1) the introduction of engineering research concepts in the areas of energy and combustion to the general public through K-12 outreach programs (2) the integration of research and education into an undergraduate and graduate combustion course through a combination of lectures, laboratory sessions and chemical kinetic simulations, and (3) providing training and research experiences for graduate and undergraduate students in the area of combustion and energy studies. 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.