单项选择题
A.Increased turbulence
B.increased mechanical efficiency
C.Increased brake mean effective pressure
D.All of the above
单项选择题 Late fuel injection in a diesel engine is indicated by low firing pressure with（）
单项选择题 In a diesel engine jacket water cooler, with seawater cooling the fresh water, the（）
单项选择题 In a medium speed diesel engine, a trunk type piston may be cooled by（） Ⅰ.oil circulation though passages in the piston crown Ⅱ.heat transfer through piston rings and liner wall