Development of a conceptual design tool to predict performance and pollutant and GHG emissions of high-speed vehicles using liquid hydrogen

At present day, it is easily noticeable how the interest for environmental impact of human activities is becoming more and more important. Space utilization is not exempt from this, thus new ways of estimating pollutant and greenhouse gases emissions of launchers are needed, especially in a conceptual design phase, during which the consequences of different design choices must be compared. Meanwhile, many new propulsion concepts are currently under design and, in particular, one promising category is that of precooled air-breathing rocket engines, represented by SABRE, from Reaction Engines Limited. This work aims at anticipating propulsive performance and emission estimations of such systems at conceptual design level. In particular, after a brief description of SABRE and Skylon, the vehicle which it is installed on, different models of increasing complexity are presented and their results compared with performance predictions of Reaction Engines Limited in order to validate them. After this, a method for using such results to predict emissions is presented. Finally, the tool is integrated in a Matlab Graphical User Interface previously created at Politecnico di Torino, to be then added to ASTRID-H, a conceptual design tool currently under development to evaluate performance of different high-speed air breathing propulsive systems architectures.