Combustion and Emissions Analysis of Alternatives

NASA’s Aeronautics Research Mission Directorate requested an analysis of alternatives (AoA) study on the following three competencies in 2020: subsonic transport acoustics, combustion and emissions, and aircraft icing. This presentation will address details specific to the combustion and emissions analysis of alternatives study. The basic process used for during the AoA study in shown in Figure 1. Figure 1. Flow chart of the Analysis of Alternative process used in this study. The combustion study team was multidisciplinary, including a wide range perspectives and areas of expertise. Inputs were collected from within NASA and a wide range of external stakeholders, including aircraft engine companies, aircraft airframe companies and other government agencies. Eight future realities for aviation were developed in preparation for the applying the AoA process, such as future realities with increased or decrease airline traffic, greater emissions stringency, or a revolution in energy infrastructure (such as hydrogen usage). Based on the inputs collected, over seventy technical elements applicable to combustion and emissions research were developed. To rank the importance of these technical elements for each future reality, a set of evaluation criterion were developed that can be generally characterized as environmental impacts, technologies enabling reduced fuel burn, and elements requiring significant NASA involvement or having significant industry pull. Using in-house codes to apply the TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) methodology, as well performing consistency checks and other analysis by the study team, a ranked set of technical elements was generated. Several research needs were identified and analyzed to determine the highest priorities for potential research by NASA in the combustion and emissions area. Results from the study will be presented.