# اختبار بسيط فى المحركات التربينية



## احمد 25 (22 مارس 2009)

اخوانى الأعزاء هذا اختبار بسيط مكون من 25 سؤال فاختبر معلوماتك عن المحركات التربينية ويارب تنال هذه الفكرة اعجابكم

*GAS TURBINE ENGINE EXAM*​
1) One function of the nozzle diaphragm in a turbine engine is to? 
A. Decrease the velocity of exhaust gases. 
B. Center the fuel spray in the combustion chamber. 
C. Direct the flow of gases to strike the turbine blades at the desired angle. 

2) What is the profile of a turbine engine compressor blade? 
A. The curvature of the blade root. 
B. The leading edge of the blade. 
C. A cutout that reduces blade tip thickness.

3) In a gas turbine engine, combustion occurs at a constant 
A. volume. 
B. density. 
C. pressure. 

4) Which statement is true regarding jet engines? 
A. At the lower engine speeds, thrust increases rapidly with small increases in RPM. 
B. The thrust delivered per pound of air consumed is less at high altitude than at low altitude. 
C. At the higher engine speeds, thrust increases rapidly with small increases in RPM. 

5) When starting a turbine engine, a hung start is indicated if the engine 
A. RPM exceeds specified operating speed. 
B. exhaust gas temperature exceeds specified limits. 
C. fails to reach idle RPM.

6) When starting a turbine engine, 
A. release the starter switch as soon as indication of light off occurs. 
B. an excessively lean mixture is likely to cause a hot start. 
C. a hot start is indicated if the exhaust gas temperature exceeds specified limits. 

7) Main bearing oil seals used with turbine engines are usually what type(s)? 
A. Labyrinth and/or carbon rubbing. 
B. Teflon and synthetic rubber. 
C. Labyrinth and/or silicone rubber.

8) When the leading edge of a first stage turbine blade is found to have stress rupture cracks, which of the following should be suspected? 
A. Overtemperature condition. 
B. Faulty cooling shield. 
C. Overspeed condition. 

9) A weak fuel to air mixture along with normal airflow through a turbine engine may result in 
A. high EGT. 
B. a lean die-out. 
C. a rich flameout.

10) What is the proper starting sequence for a turbojet engine? 
A. Ignition, starter, fuel. 
B. Starter, ignition, fuel. 
C. Starter, fuel, ignition. 

11) Jet engine turbine blades removed for detailed inspection must be reinstalled in 
A. a specified slot 180° away. 
B. the same slot. 
C. a specified slot 90° away in the direction of rotation.

12) Standard sea level pressure is 
A. 29.92" Hg. 
B. 29.00" Hg. 
C. 29.29" Hg. 

13) Using standard atmospheric conditions, the standard sea level temperature is 
A. 59 °F. 
B. 29 °C. 
C. 59 °C. 

14) The velocity of subsonic air as it flows through a convergent nozzle 
A. increases. 
B. decreases. 
C. remains constant. 

15) The velocity of supersonic air as it flows through a divergent nozzle 
A. is inversely proportional to the temperature. 
B. decreases. 
C. increases.

16) The pressure of subsonic air as it flows through a convergent nozzle 
A. remains constant. 
B. increases. 
C. decreases.
17) The pressure of supersonic air as it flows through a divergent nozzle 
A. increases. 
B. decreases. 
C. is inversely proportional to the temperature. 

18) What is the primary factor which controls the pressure ratio of an axial flow compressor? 
A. Compressor inlet pressure. 
B. Compressor inlet temperature. 
C. Number of stages in compressor. 

19) Severe rubbing of turbine engine compressor blades will usually cause 
A. galling. 
B. bowing. 
C. cracking. 

20) Compressor stall is caused by 
A. a low angle of attack airflow through the first stages of compression. 
B. rapid engine deceleration. 
C. a high angle of attack airflow through the first stages of compression.

21) Continued and/or excessive heat and centrifugal force on turbine engine rotor blades is likely to cause 
A. galling. 
B. creep. 
C. profile. 

22) A cool-off period prior to shutdown of a turbine engine is accomplished in order to 
A. prevent seizure of the engine bearings. 
B. prevent vapor lock in the fuel control and/or fuel lines. 
C. allow the turbine wheel to cool before the case contracts around it.

23) The compression ratio of an axial flow compressor is a function of the 
A. number of compressor stages. 
B. rotor diameter. 
C. air inlet velocity. 

24) If the RPM of an axial flow compressor remains constant, the angle of attack of the rotor blades can be changed by 
A. changing the compressor diameter. 
B. changing the velocity of the airflow. 
C. increasing the pressure ratio. 

25) A turbine engine hot section is particularly susceptible to which kind of damage? 
A. Cracking. 
B. Scoring. 
C. Galling.​ملحوظة هذا الإختبار وضعته من قبل فى منتديات اخرى ولكى تعم الفائدة وضعته فى هذا المنتدى  ​​​


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## شفق الصباح (22 مارس 2009)

حقيقةً أخي أسألة جمياة وموضوعية ومفيدة وتعمل رفرش لزاكرة كل فني او مهندس
بارك الله فيك
وفي أنتظار المزيد


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## مهندس أيمن حسن (24 مارس 2009)

بارك الله فيك

بس لو فية اجابات تنزلها يبقى تمام اويي


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## احمد 25 (3 أبريل 2009)

شكرا على اهتمامكم ومروركم الكريم على هذا الموضوع
ولمن يريد الإجابة فهى كالتالى:
1-(c)
2-(c)
3-(c)
4-(c)
5-(c)
6-(c)
7-(a)
8-(a)
9-(b)
10-(b)
11-(b)
12-(a)
13-(a)
14-(a)
15-(c)
16-(c)
17-(b)
18-(c)
19-(a)
20-(c)
21-(b)
22-(c)
23-(a)
24-(b)
25-(a)

تمت الإجابة بحمد الله واتمنى ان ينتفع بها الجميع


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## مهندس أيمن حسن (3 أبريل 2009)

شكرا جزيلا على الاجابات كدة الموضوع كمل


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## saman ali (5 يناير 2011)

*المضخات العمودية والافقية للسوائل الغازية*

:85::81::81:ارجو مساعدتي في موضوعي وهو(فرق بين المضخات العمودية والافقية للسوائل الغازية من بروبان الى ديكان في شركة الغاز )ارجو الرد بالسرعة الممكنة وشكرا:75::75:


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## Omar Sawalha (11 يناير 2011)

*مشكووووووور جدا*​


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