TE LAB-MORSE TEST ON A MULTI-CYLINDER PETROL ENGINE

Ex.No:                                                                                                                                                             Date:

 

MORSE TEST ON A MULTI-CYLINDER PETROL ENGINE

 

Aim: To conduct Morse test on a multi-cylinder petrol engine and determine the frictional power for the engine.

 

Specification of engine:

  Four stroke 4 – cylinder ZEN petrol engine, 1294 CC capacity, water cooled variable speed.

 

Rated speed              : 2000 to 2500 rpm

 

Starting by                 : battery start by ignition method

 

Loading                     : by eddy current dynamometer 10HP at 3000 rpm,

 

Spring balance          : 0 to 50 Kg

 

Procedure:

 

1.      The Morse test is adopted to find out IP of each cylinder. First calculate the brake power of the engine when all the cylinders are in operation at constant speed and load. i.e load up to 15 to 20 kgs.

 

2.      One of the cylinder (say cylinder no 1) is cut off so that it does not develop any power. This is done by operating knife switch provided at front panel near the engine. The speed of the engine decreases,

 

3.      Take down the spring balance reading and speed of the engine.

 

4.      The brake power is now measured in these new conditions which gives the brake of the remaining cylinders.

 

5.      Repeat the procedure for other two cylinders and measure the brake power each time keeping the speed constant.

 

Tabular column:

S.No.	Condition	Dynamometer load, W (kg)	Power output, BP (kW)
1.	All cylinders firing		BP     =
2.	Cylinder 1 cut-off		BP234 =
3.	Cylinder 2 cut-off		BP134 =
4.	Cylinder 3 cut-off		BP124 =
5.	Cylinder 4 cut-off		BP123 =

 

Formulae:

 

Let      IP₁, IP₂, IP₃ and IP₄ are indicated power of each cylinder,

           FP₁, FP₂, FP₃ and FP₄ are frictional power of each cylinder,

 

We know the brake power of engine when all cylinders are working

BP = Indicated power of all cylinder – Frictional power of all cylinder

BP = (IP1 + IP2 + IP3 + IP4) – (FP 1 + FP2 + FP3+ FP4)

- (1)

When the cylinder no.1 is cutoff, brake power of remaining cylinder is

BP1 = (0 + IP2 + IP3+ IP4) - (FP1 + FP2 + FP3+ FP4)

- (2)

 

 

Then subtract equation (2) from (1) we get IP of cylinder (1)

 

Therefore,               Indicated power of 1^st cylinder IP₁ = BP – BP₁

 

                  Similarly,               Indicated power of 2^nd cylinder IP₂ = BP – BP₂

 

                        Indicated power of 3^rd cylinder IP₃ = BP – BP₃

 

      Indicated power of 4^th cylinder IP₄ = BP – BP₄

 

Total indicated power of the engine, IP = IP₁ + IP₂ + IP₃+ IP₄

 

Pre Lab Questions:

1.         What are the 4strokes of SI engines?

2.         What is the working cycle of SI Engine?

3.         List out the performance parameters?

4.         Indicate the different types of loads?

5.         Differentiate SFC and TFC?

6.         What are the different methods to find frictional power?

Post Lab Questions:

1.         Differentiate brake power and indicated power?

2.         Define brake thermal efficiency?

3.         Indicate mechanical efficiency in terms of BP and IP?

4.         Explain the procedure for finding frictional power using Morse test?

5.         What is the type of dynamometer used for measuring the motor output? 

6.         Give firing order for a four and six cylinder engines.

 

 

Conclusion: 

 

 

PO Attainment:

Composed By:      

 R.Satheesh, M.E., Asso.Prof.,