1. MT 313 IC ENGINES LECTURE NO: 03 (19 Feb, 2014) Khurram engr014@yahoo.com Yahoo Group Address: ICE14

2. QUESTIONS What is the advantages and Disadvantages of four stock engines? What is the advantages and Disadvantages of two stock engines? What is the advantages and Disadvantages of Petrol engines? What is the advantages and Disadvantages of Diesel engines? What is the advantages and Disadvantages of Wankel stock engines? Compare 4 - stroke & 2 - stroke Engine?

3. QUESTIONS Describe working principles of Wankel engines? Numerate performance parameters of the I.C. engines?

5. Ideal cycles are simplified

6. Ideal Cycles More realistic than Carnot cycle. Internally reversible but not totally. Idealizations: – No friction – Expansions and compressions – quasi-equilibrium – Heat transfer is negligible

7. Different Processes IsobaricIsometric Adiabatic ΔT ≠ 0 but Q = 0 Isothermal ΔT = 0 but Q ≠ 0 Cyclic If clockwise – heat engine If counterclockwise – heat pump

8. Area inside the cycle represents net work out for TS or PV diagrams.

9. Otto Cycle, ideal for spark ignition engines

10. TS plot of the Otto Cycle

11. Efficiency vs Compression Ratio Higher ratios produce autoignition and knocking

12. Efficiency vs ratio of specific heats Air Combustion mixture He

13. The Ideal Otto Cycle