Advances in Diesel-LNG Internal Combustion Engines

Abstract

Diesel-LNG internal combustion engines (ICEs) are the most promising light and heavy-duty truck (HDT) powering solution for a transition towards a mixed electric-hydrogen renewable energy economy. The diesel-liquid CH4 ICEs have indeed many commonalities with diesel-liquid H2 ICEs, in the infrastructure, on-board fuel storage, and injection technology, despite the fact H2 needs a much lower temperature. The paper outlines the advantages of dual fuel (2F) diesel-LNG ICEs developed adopting two high-pressure (HP) injectors per cylinder, one for the diesel and one for the LNG, plus super-turbocharging. The diesel-LNG ICEs provide high fuel energy conversion efficiencies, and reduced CO2, PM, and NOx emissions. Super-turbocharging permits the shaping of the torque curve while improving acceleration transients. Diesel-LNG ICEs may also clean up the air of background pollution in many polluted areas in the world. Computational results prove the steady-state advantages of the proposed novel design. While the baseline diesel model is a validated model, the 2F LNG model is not. The perfect alignment of the diesel and diesel-LNG ICE performances proven by Westport makes however the proposed results trustworthy.