ic engine power engg

IC -ENGINE

BY PROF. AVINASH 5 TH S E M M E C H A N I C A L MECH_INT CLASSES

CONTENTS 1.

2.

3.

4.

5.

6.

7.

8.

Nomenclature of ICE Engine testing Types of power Power measurement tests ICE efficiencies BSFC Heat balance sheet Pollution control

NOMENCLATURE  Cylinder bore(D)  Stroke(L)  Dead centre  Swept volume

 Clearance volume  Cylinder volume  Compression ratio

ENGINE TESTING  To get information that cannot be calculated  To confirm the design data  To meet customer specifications of power and fuel

consumption  Two types of tests: 1. Commercial tests 2. Thermodynamics tests

Commercial tests  Rated power with guaranteed fuel consumption in    

kg/ Kw-hr The quantity of lubricating oil consumed on brake power per Kw-hr Quantity of cooling water in kg/ kw-hr Steadiness of engine under varied load conditions Overload carrying capacity of engine

Thermodynamic tests  Used to measure various losses due to different

causes  To measure mechanical and thermal efficiencies of engine  Draw heat balance account  Required data 1. IP, BP, FC &CV 2. Heat carried away by cooling water 3. Heat carried by exhaust gas

TYPES OF POWER A. INDICATED POWER IP = P L A N B. BRAKE POWER BP= (W-S)R * 2 π N

CONTD. C. FRICTIONAL POWER FP = IP - BP

Morse test  Used for calculating FP in a 4S-engine  Procedure:  First engine is run at constant speed and Brake

power of the engine is measured when all the cylinders are working (I1+ I2+I3+I4) = (BP) ENGINE + (F1+F2+F3+F4)  The first cylinder is cut off, so

(I2+I3+I4) = (BP) 2,3,4 + (F1+F2+F3+F4)

Contd.  Now only cylinder 2 is cut-off

(I1 +I3+I4) = (BP) 1, 3, 4 + (F1+F2+F3+F4)  Cylinder 3 is cut off (I1+ I2 +I4) = (BP) 1,2,4 + (F1+F2+F3+F4)  Cylinder 4 is cut-off (I1+ I2+I3) = (BP) 1,2,3 + (F1+F2+F3+F4)  Hence, I1 = (BP) ENGINE – (BP)2,3,4 I2 = (BP) ENGINE – (BP)1,3,4

Contd.

I3 = (BP) ENGINE – (BP)1,2,4 I4 = (BP) ENGINE – (BP)1,2,3  Thus IP of engine is IP = (I1+ I2+I3+I4)  And FP = IP - (BP) ENGINE  And

Efficiencies in ICE

Contd.

BSFC:

Heat balance Sheet Heat supplied

kJ/min

%

Heat distributi on

kJ/min

1. Heat supplied by the fuel

100

1.Heat eq. ` of BP 2. Heat in cooling water 3. Heat in exhaust gases 4.

Unaccounte d heat

Total

100

Total

%

100

Pollution control  Pollutants in Exhaust of petrol and diesel engine(SS)  Effect of pollution in Environment(SS)  Exhaust gas analysis  Pollution control norms

Thank you