Split-cycle combustion system could reduce vehicle emissions

UK engineering company Ricardo is researching a split-cycle combustion system aimed at reducing the carbon emissions of heavy-duty vehicles.

The CoolR project — a joint effort with Brighton University — will examine a new split-cycle combustion concept instead of focusing on refining existing four-stroke engine technology.

Ricardo first demonstrated a split-cycle isothermal compression engine for power generation in the 1990s, using water injection to achieve high thermal efficiencies. Now the company wants to use cryogenic liquid injection to do the same in a vehicle.

Allowing for the energy costs of cryogen production, the company hopes to improve the thermal efficiency of the engine by around 40 per cent, which it claims is significantly better than other technologies researched such as exhaust heat recovery concepts.

‘We believe that the CoolR split-cycle cryogenic injection combustion concept offers the prospect of very significant improvements in thermal efficiency and hence reduced carbon-dioxide emissions in the heavy vehicle sector,’ said project director Nick Owen.

The one-year feasibility project, which is part funded by the Technology Strategy Board, will address the key issues that industry would face if such technology were to be adopted and will also develop a roadmap for creating a prototype engine.