Internal Combustion Engines

Sample Exam 2 2nd semester 1428-29

Student Name:

Student Number: - - ( )

1) A- A low speed diesel engine operating on the constant pressure cycle has a compression ratio of 12:1. Air temperature and pressure before compression are 27oC and 130 kN/m2 respectively. The temperature after combustion was 1027oC, g = 1.4. The volume at the beginning of the compression was 480 cm3.

 

Process 1-2 ( )

V1 / V2 = r = 12

T1 = 27 + 273 = 300 K

 

P (kN/m2)

V (cm3)

T (K)

Point 1

130

480

 

Point 2

*

*

*

 

 

 

 

 

 

 

 

 

 

Process 2-3 ( )

T3 = 1027 + 273 = 1300 K

 

P (kN/m2)

V (cm3)

T (K)

Point 2

*

*

*

Point 3

#

#

# 1300

 

 

 

 

 

 

 

 

 

 

 

 

Process 3-4 ( )

 

P (kN/m2)

V (cm3)

T (K)

Point 3

#

#

# 1300

Point 4

480

 

 

 

 

 

 

 

 

 

 

Process 4-1 ( )

 

P (kN/m2)

V (cm3)

T (K)

Point 4

480

Point 1

* 130

* 480

*

 

 

 

 

 

 

 

 

 

 

 

1) B- Sketch a pV diagram of the cycle and show the Win , Wout , Qin , and Qout.

 

C- Find the volume of the cylinder Vs.

 


D- Write down the equation for the engine efficiency.

 

 

 

 

 

 

 

 

1) C- Complete the table below:

 

 

Process name

1-2

 

 

 

2-3

 

 

 

3-4

 

 

 

4-1

 

 

 

 

 

2- What is meant by the following:

 

PPM

 

SMOG

 

DOHC

 

SIE

 

3) A- Complete the following table (types of engines)

 

Engine type

1

2

Engine cooling

Water cooled engines

Air cooled engines

 

 

 

 

 

 

 

 

 

 

 

 

 

B-   complete the table

 

Advantages

Disadvantages

Water cooled engines

-

-

-

-

Air cooled engines

-

-

-

-

 

 

4- What are the car pollutants?

 

Pollutants

Car Sources

Effects