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Internal Combustion Engines |
Sample Exam 2 (1427-1428) 2nd semester |
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Student Name: |
Student Number: - - ( ) |
1- A) What are the differences between the following ? (ما الفروق بين التالي؟)
i- Gasoline engine & Diesel engine
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ii- Lean mixture& Rich mixture
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iii- Isothermal process & Adiabatic process
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B) What is the relationship between the following- and units? (ما العلاقة بين التالي والوحدات؟)
- Heat (Q) & temperature (T)
- Work (W) & cylinder pressure (p)
C) Write down the differences between the following(أذكر الفروق بين التالي) :
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Gasoline fuel |
Alcohol fuel |
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Source |
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Advantages |
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Engine modifications |
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D) Write down the gasoline engine combustion problems(اذكر مشاكل الاحتراق) :
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Name of the problem |
Explain the problem |
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E) Identify the following thermal process shown in the cycle (تعرف على الإجراءات الحرارية)
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Process Name |
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A-B B-C C-A |
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- Is the net work (+) or (-)?
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2) A low speed diesel engine operating on the constant pressure cycle has a compression ratio of 14:1. Air temperature and pressure before compression are 27oC and 130 kN/m2 respectively. The temperature after combustion was 1227oC, γ = 1.4. The volume at the beginning of the compression was 70 cc.
A) complete the following table (أكمل الجدول)
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Point No. |
Volume |
Pressure |
Temperature |
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1 |
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2 |
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3 |
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4 |
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B) Sketch a p-V diagram of the cycle and show Win, Wout, Qin, and Qout (أرسم الدورة ووضح التالي)
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C) Write down the equation for the cycle heat efficiency |
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