Using appropriately labelled diagrams and figures, describe and discuss in detail what do you understand by the RCCI mode/concept of the engine combustion (Approx. 850 - 900 words)
Task 2
Using WAVE engine modelling, build a 1.6L direct injection (DI) engine with the specifications and model initial conditions as shown below.
Table 1 – Engine specifications
Parameter Value
Type / Fuel Inline, 4-stroke / Indolene
Number of Cylinders 4
Bore 78 mm
Stroke 83.6 mm
Connecting rod length 134.7 mm
Displacement 1.6 L
Compression ratio 10.4
Diameter of the intake valve/Max lift 32/9 mm
Diameter of the exhaust valve/Max lift 26.8/9 mm
Number of Intake Valves/Exhaust valves 2/2
Table 2 – Model initial conditions
Parameter Value
Ambient Temperature 293 K
Ambient Pressure 1.01325 Bar
Piston Top Temperature 550 K
Cylinder Head Temperature 495 K
Cylinder Liner Temperature 450 K
You may assume the default physical parameters and sub-models for the DI engine model. Run the model for engine speeds starting from 1500 rpm and up to 5500 rpm. Activate the emissions sub-model to find the engine emissions.
Task 3
Produce comparison plots for the following engine performance parameters and emissions:-
a) Engine power output
b) Torque
c) Brake specific fuel consumption (BSFC)
d) Mean effective pressure (mep)
e) Thermal efficiency
f) Peak cylinder temperature and pressure
g) Pressure rise rate (PRR)
h) Emissions (NOx, CO and hydrocarbons (HC)
Task 4
For the above engine model, simulate RCCI engine combustion by using the following two fuel combinations (associated fuel files will be provided on the Blackboard).
i. Gasoline, diesel
ii. Diesel, hydrogen
Choose an appropriate WAVE combustion model to model the RCCI combustion. Compare your results for these two cases with that of the engine model built in the Task 2 above by plotting comparison engine performance and emissions curves. Discuss your modelling results for all the three scenarios and elaborate on your findings.