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 