Formula of IC Engine

This is a formula of Internal Combustion Engine on Element of Mechanical Engineering Sem 1

1. BHAGWAN MAHAVIR INSTITUTE OF ENGINEERING AND TECHNOLOGY Topic:- Combustion EnginesFormulas of Internal Guided By:- Kailas Sir Branch:- CSE Sem - 1

2. Prepared By:- Darshil Shah Chintan Rajpara Darshan Lathiya

3. Introduction

4. In 1876 four stroke engine based on Otto cycle was developed by a German engineer Nikolous Otto.Which revolutionized the development of Internal Combustion engines and are even used till date.Diesel engine was developed by another German engineer Rudolf Diesel in the year 1892.

5. 1.Indicated power of a Four-stroke Engine I.P.= P m L A N KW 60000×2 P m =Actual Mean Effective pressure,N /m2 L=Length of stroke,m A=Area of cross section of the cylinder,m2 N=RPM of engine crankshaft

6. 2 .Indicated power of a Two-stroke Engine I.P.= P m L A N KW 60000 P m =Actual Mean Effective pressure,N /m2 L=Length of stroke,m A=Area of cross section of the cylinder,m2 N=RPM of engine crankshaft

7. 3. Brake Power B.P.= 2∏NT = P mb LAN KW 60000 60000 P m =Actual Mean Effective pressure,N /m2 P mb = Brake mean effective pressure, N/m2 L=Length of stroke,m A=Area of cross section of the cylinder,m2 N=RPM of engine crankshaft T=W×R N.M [ where, W=Net Load acting on the break drum,N R= Radious of the brake drum,m ]

8. 4. Friction Power F.P.= I.P – B.P. I.P.=Indicated power B.P.=Brake Power

9. 5. Mechanical efficiency:- Ƞ mech = B.P I.P I.P.=Indicated power B.P.=Brake Power

10. 6. Indicated Thermal Efficiency Ƞ it = I.P m f ×C.V m f =Mass of fuel supplied,kg /sec C.v =calorific value of fuel, j/kg I.P.=Indicated power

11. 7. Brake Thermal Ƞ b t = B.P m f ×C.V m f =Mass of fuel supplied,kg /sec C.v =calorific value of fuel, j/kg B.P.=Brake Power

12. 8. Relative efficiency:- Ƞ rel = Ƞ it Ƞ air Ƞ it = Indicated Thermal efficiency Ƞ air= Air Standard efficiency

13. 9. Air Standard efficiency Ƞ air= 1- 1 (r) ϒ -1

14. 10. Volumetric efficiency:- Ƞ vol = Actual volume of charge/air sucked at atm. Condition Swept volume

15. 11. Specific output Specific output = B.P. A B.P.=Brake Power A=Area of cross section of the cylinder,m2

16. 12. Specific fuel consumption:- SFC = m f kg/kWh B.P. m f =Mass of fuel supplied,kg /hr B.P.=Brake Power, kw

17. Thank You