Exam 1-B

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 Clearance Volume

Specific fuel consumption

Thermal efficiency

Engine Compression ratio

Engine angular speed

 

 

 

 

 

 

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

 

a- Force (F) & Pressure (p)

 

b- Engine Torque (Te) & Engine Capacity (Ve)

 

c- Indicated power (Pi) & Brake power (Pb)

 

 

1- C) What are the differences between the following? ما الفرق بين التالي  أجب عن 2 فقط -
a- 4-Stroke Engines & 2-Stroke Engines

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b- Engine gross power & Engine net power

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c- Engine brake dynamometer Method & Morse test Method

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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- Indicated Power (Pi)

 

 

 

where:

 

 

 

b- Engine mechanical efficiency (hm)

 

 

where:

 

 

c- engine torque (Te)

 

 

where

 

 

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

 

a- Ignition spark location &

b- Ignition advance

c- TDC and BDC locations

d- Valves overlapping

e- Atmospheric pressure

 

 

 

 

 

 

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

 

CI engines

SI engines

Common features
صفات مشتركة

 

 

 

Different features
صفات مختلفة

 

 

 

Advantages
المميزات

 

 

 

 

 

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

 

Dieseling (run-on) 

Diesel-knock

What is

 

 

 

 

Causes

 

 

 

 

Effects

 

 

 

 

 

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

i- Engine A consumes fuel as (21 kg/h) or

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

 

 

 

 

 

 

 

4) SI 4-strok engine, has the following specifications:

- Number of cylinder (n) is 4

- Engine swept volume (Ve) is 1600 cc

- Engine maximum brake power (Pb) is 100 kW at 5000 rpm

- Engine maximum Torque (T) is 120 Nm at 3000 rpm

- Engine compression ratio (r) is 10

- Engine Bore to stroke ratio (D/L) is 1.2

Find:
a) engine clearance volume (Vc),

 

 

 

 

 

 


b) engine brake mean effective pressure (bmep),

 

 

 

 

 

 


c) engine torque at maximum power (T),

 

 

 

 

 

 

 

d) engine stroke (L).