Recently, IMO has been strengthening its regulations on CO2 emission from marine vessels. One of the effective solutions to comply with these regulations targeting marine engines is to increase the thermal efficiency with higher compression ratios. However, the optimum compression ratio depends on engine output power. Given this, we have developed a variable compression ratio (VCR) system for two stroke crosshead engines for marine applications that can change compression ratios seamlessly during engine operations.
The newly developed VCR system demonstrated that it can change compression ratios at its will while the engine is running. In addition, the authors found that the VCR system can also decrease fuel consumption and CO2 emissions with a higher compression ratio. In consideration of these points, the VCR system was awarded the 2018 Marine Engineering of the Year (Dokou’s Memorial Award).
