The revolutionary R6 Cycle

The R6-H2 engine is predicted to be the definitive hydrogen engine for the 21st Century because its revolutionary rotary architecture and 6-phase thermodynamic cycle (patent EP3765711, 2022) eliminates the problem of engine knock (detonation) and enables high load homogenous charge compression ignition (HCCI) H2 combustion with >50% brake thermal efficiency and <0.2g/kWh NOx emissions without aftertreatment. Its 6-phase thermodynamic cycle completes in three pairs of phases in each rotation of the shaft: (1) power/ 1st compression, (2) exhaust/ scavenge-EGR, (3) 2nd compression/ intake. The illustration below shows the key stages in the 6-phase cycle.

R6 6 Phase Cycle

R6 6 Phase Cycle

R6-H2 Cycle

The graph below illustrates the R6 cycle chamber volumes across 360o of rotation.

Libralato cycle volumes with valve timings

The graph below show a comparison between the R6 cycle and the Otto and Diesel cycles.

R6 cycle comparison with Otto and Diesel

The graph below shows the mechanical advantage of R6-H2 rotary architecture in terms of the torque generated from the same pressure at top dead centre.

    R6 Mechanical Advantage

The illustration below shows how R6-H2 engine can utilise HCCI combustion in a way that conventional engines cannot.

    R6-H2 HCCI crop

The charts below show the modelling methodology and assumptions made based on the engine architecture and 6-phase cycle.

    R6-H2 models & assumptions