Improved combustion control for the lean-burn marine gas engine by advanced control of inlet and exhaust valves.

- By theoretical means, simulation and practical tests show the potential and produce a basis for a new engine control system by mean of VVT.

- Define the test set-up and perform tests on the RR K-engine in the MARINTEK engine laboratory for verificatio n of capability.

- Plan for full scale verification in a gas drive skip

All to meet challenges 1 and 2.

Challenges 1:

A fuel efficient high power gas engines is ideally run with a rather small margin to both misfire and knocking.

Challenges 2:

The m arket for gas driven ships will expand driven by fuel economy and environmental aspects. To keep position and even expand it is of vital importance to handle the excessive hydrocarbon slip from the gas engine. For a marine engine fuel from LNG the hydroca rbon slip is close to pure methane, considered as an even more aggressive GHG than CO2.

Especially in marine use when running on medium to low load, the state-of- art lean-burn gas engines still have quite much higher hydrocarbon emission than a diese l engine. It is also foreseen future regulations on THC emission where strict limits are going to be specified.

A reduced methane slip will certainly also have a quite significant effect on efficiency/fuel consumption.