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

 

1 A) What are the units of the following physical quantities? ما وحدات الكميات الفيزيائية التالية

Engine Weight	Engine FC	Engine mechanical efficiency	Engine Net Power	Brake mean effective pressure

 

1 B) What are the relationships between the following ما العلاقة بين التالي؟ - أجب عن 2 فقط

a- Force (F) & Torque (T)

 

b- Indicated power (P_i) & Brake power (P_b)

 

c- Mechanical efficiency (h_m) & Friction Power (P_f)

 

 

1 C) What are the differences between the following? - ما الفروق بين التالي أجب عن 2 فقط

a- SI engines & CI engines

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b- Fuel consumption & Specific fuel consumption 

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c- Morse test & motoring test methods

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2 A)- Write down the equation of the following, and identify each term اكتب معادلات المتطلبات التالية وعرف كل حد بالمعادلة-  أجب عن 2 فقط

a- Engine compression ratio (r)

 

 

 

where:

 

 

 

b- Engine volumetric efficiency (h_v)

 

 

 

where:

 

 

 

c- Brake Power (P_b)

 

 

 

where

 

 

 

 

2 B)  Place the following on the chart:  وضح على الشكل المطلوبات التالية

a- Ignition spark location

b- Power stroke

c- TDC and BDC locations

d- Clearance volume

e- Cylinder volume

 

 

 

3 A) Complete the following table showing the difference between the following اكمل الجدول التالي مبين الفرق بين التالي:

Air/fuel mixture	Rich	Poor
Air/fuel ratio
Exhaust gases components
Advantages

 

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

	Detonation	Pre-ignition
What is
Causes
Effects

 

3 C) Which engine hase less fuel consumption? and why?

i- Engine A has brake power of 120 kW, and SFC is 0.3 kg/(kW h)

ii- Engine B consumes fuel as (32 L/h) if fuel density ρ = 0.7 kg/L

 

 

 

 

 

 

 

4) 4-stroke engine has a swept volume (V_e) of 1.6 L and a compression ratio (r) of 8. The number of cylinder (n) is 4 and the bore diameter (D) is 8.5 cm. The imep is 1120 kPa, at 3000 rpm

 

a- Find the cylinder swept volume (V_s).

 

 

 

 

 

 

 

b- Find the clearance volume (V_c).

 

 

 

 

 

 

 

 

c- Find the engine stroke (L).

 

 

 

 

 

 

 

 

d- Find the engine indicated power (P_i)