1. Experiment #4 IC Engine

4. Indicator Diagram
expansion
ignition
compression
intake
exhaust
The indicated work per cycle is computed from the area under the p-v diagram
Indicated power =
Brake power = indicated power -friction power Pb = Pi-Pf

5. Experimental Apparatus
Controls:
Throttle setting
Load valve
Instrumentation:
Engine rpm
Dynamometer pressure
Fuel flow rate
Cylinder head
temperature
Oil temperature
Throttle
Engine rpm

6. 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

7. 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

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

9. Engine Parameters (continued)
where

10. Report PLEASE REPORT YOUR ANSWERS IN SI UNITS
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