1. Internal Combustion Engine (ICE) Performance ME 252 Thermal Fluid Systems G. Kallio

2. ICE Performance Measures Indicated work & power – work based upon the recorded cylinder P vs. V diagram (Otto  ideal work) –where: W cycle,net = net work per cylinder per complete cycle n = number of cylinders  = crankshaft rotational speed (rev/s) N = number of crankshaft revolutions per complete cycle (= 2 for 4-stroke, = 1 for 2-stroke)

3. ICE Performance Measures, cont. Mean effective pressure (mep) – the average pressure, if acted upon by the piston during the entire power stroke, that would produce the actual net work Brake work & power – output of engine under load, usually measured at flywheel by a dynamometer; it is less than indicated power due to friction and parasitic loads

4. ICE Performance Measures, cont. Mechanical efficiency (  m ) Volumetric efficiency (  v )

5. ICE Performance Measures, cont. Specific fuel consumption (sfc)