LIQUID HYDROGEN-CRYOFUEL IN GROUND TRANSPORTATION.

Abstract

Hydrogen fueled internal combustion engines show promise in reducing polluting exhaust emissions. Internal cryogenic mixture formation especially enables exhaust emissions below the limits of existing regulations. Injection pressure requirements for internal mixture formation still require high pressure liquid hydrogen fuel pumps. LH//2 can be handled and stored onboard a vehicle similar to other fuels such as liquefied petroleum gases and liquefied natural gas. LH//2 fuel tanks suitable for automotive application are now state-of-the-art. Tank refilling can be made safely by automatically operated refilling stations. Two research activities have been started between DFVLR and two major automobile manufacturers in Germany. Different types of mixture formation and engine conversion for LH//2 fueled automotive vehicles are the subject of this R&D. By adjoining the heat sinking capability of LH//2 by cryogenic mixture formation to the internal combustion engine, performance can be improved considerably. This seems to be the most efficient measure in the development of optimized hydrogen fueled internal combustion engines.