Bypass turbocharging

Bypass turbocharging routes part of the exhaust gas around the turbine through an exhaust gas bypass (EGB), trimming the air supply so the engine stays efficient away from the matched design point. On MAN two-stroke engines the EGB optimizes SFOC across the part-load band, roughly 50 to 85 percent load, and the low-load band of about 25 to 70 percent. The related turbocharger cut-out, used on larger-bore engines with more than one turbocharger, takes a unit offline at low load to hold scavenge pressure. Both methods support Tier III exhaust gas recirculation matching by keeping receiver temperature and pressure in range.