Sample Exam 1	Internal Combustion Engines	2nd semester 1428-1429
Student Name:		Student Number:

 

1- What are the units of the following physical quantities? ما وحدات الكميات الفيزيائية

 

Density	Engine swept volume	Volumetric Efficiency	Power	Brake mean effective pressure

 

 

2-What are the relationships between the following ما العلاقة بين التالي؟

 a- Force (F) & Work (W)

 

 

b- Engine Power (P) & Engine Angular velocity (w)

 

 

c- Fuel Consumption (FC) & Specific Fuel Consumption (SFC)

 

 

 

3- What are the differences between the following? ما الفروق بين التالي

a- Otto cycle & Diesel cycle

-

-

b- Lean mixture &  Rich mixture 

-

-

c) Engine Brake Dynamometer & Motoring Test Methods

-

-

 

 

4- B) Write down the equation of the following, and identify each term أكتب معادلات المتطلبات التالية وعرف كل حد بها:

a) Engine swept volume:

 

Where:

 

 

 

b) Engine specific fuel consumption

 

 

where:

 

 

 

c) Engine thermal efficiency

 

 

where:

 

 

 

5) Write down the differences between the following (أكتب الفروق بين التالي):

	Detonation	Diesel-knock
What is
Causes
Effects

 

 

 

6) Write down the factors affecting combustion of SI engines(اكتب العوامل التي تؤثر على الاحتراق للبنزين) :

The factor	How it affects the combustion

 

 

 

7- Place the following on the chart:

a- Valves opening and closing locations

b- Ignition spark location

c- Crank shaft angles

d- The engine strokes

e- Cam shaft angles

f- Maximum pressure

 

 

 

 

8) Which car has less fuel consumption? and why?

i- Car A consumes fuel as (8 L/100 km) or

ii- Car B consumes fuel as (12 km/L)

 

9) An engine has four cylinders, the cylinder bore is 100 mm and the bore/stroke ratio is 1.2, maximum pressure is 5400 kPa. When the engine is tested with and electric swinging field dynamometer it gives the following readings: brake power reading was 92 kW at 5400 rev/min, and when it is motoring tested at the same engine speed the reading was 8.5 kW. Find:
a) engine swept volume,
b) engine friction power,
c) engine mechanical efficiency,

d) engine torque at 5400 rev/min,

e) the maximum force on the piston head.
f) the quantity of air entering the engine if the volumetric efficiency is 85%