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 (Pi) & Brake power (Pb)


c- Mechanical efficiency (hm) & Friction Power (Pf)



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

a- SI engines & CI engines



b- Fuel consumption & Specific fuel consumption 



c- Morse test & motoring test methods





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)








b- Engine volumetric efficiency (hv)








c- Brake Power (Pb)









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



Air/fuel ratio





Exhaust gases components











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




What is
















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 (Ve) 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 (Vs).








b- Find the clearance volume (Vc).









c- Find the engine stroke (L).









d- Find the engine indicated power (Pi)