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Experiment #4 IC Engine. Indicator Diagram. The indicated work per cycle is computed from the area under the p-v diagram Indicated power =. expansion. ignition. compression. intake. exhaust. Brake power = indicated power -friction power P b = P i -P f. Experimental Apparatus.
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Indicator Diagram The indicated work per cycle is computed from the area under the p-v diagram Indicated power = expansion ignition compression intake exhaust Brake power = indicated power -friction power Pb = Pi-Pf
Experimental Apparatus • Controls: • Throttle setting • Load valve • Instrumentation: • Engine rpm • Dynamometer pressure • Fuel flow rate • Cylinder head • temperature • Oil temperature Throttle Engine rpm
Objectives • Using a single cylinder four stroke engine • Mea sure engine power, rpm and fuel consumption at difference throttle settings • Plot relevant engine parameters as a function of engine rpm and discuss the results
Engine Parameters • Measured Brake power (W): • Brake specific fuel consumption (kg/Nm): • Brake mean effective pressure (N/m2): • Brake Torque (Nm): • Fuel/Air mass ratio Use hp = 0.8
Engine Parameters (continued) Volumetric Efficiency = Effects of: air friction chocking backflow, etc hv Engine rpm Conversion Efficiency: Mechanical Efficiency Use HHV = 44 MJ/kg, and
Report • For each throttle setting (1/4,1/2,3/4,full) • Compute power, torque,sfc,mep, conversion efficiency • Plot these computed quantities against engine rpm • Discuss the results using references, and the relationships in the notes • Determine the most desirable engine speed for power,torque and efficiency • Compare the efficiencies with that of an idea Otto cycle • Answer the question on connecting rod stress PLEASE REPORT YOUR ANSWERS IN SI UNITS