MODULE 15 CHAPTER 2 QUIZ 6

NOTE

TO CHECK YOUR PREPARATION ,PLZ WRITE DOWN YOUR SELECTED OPTIONS (A,B,C) ON ROUGH PAGE AND  AT THE END OF QUIZ , VERIFY YOUR SELECTED OPTIONS WITH THE CORRECT OPTIONS GIVEN BELOW

51. Full reverse power is approximately.

A. 95% of forward thrust.

B. 75% of forward thrust.

C. 50% of forward thrust.

52. The efficiency of a gas turbine would be greatest at.

A. cold temperatures.

B. low pressure.

C. hot temperatures

53. In a gas turbine engine, turbine section.

A. temperature decreases along with pressure and velocity.

B. velocity decreases and pressure increases.

C. velocity increases and pressure decreases.

54. As air density changes the RPM of a gas turbine engine will change. How is RPM kept at a constant speed?.

A. It is not.

B. Automatically by a simple engine device.

C. Manually by the pilot.

55. With fixed throttle and increasing altitude, the fan on a high by-pass engine will.

A. decrease RPM.

B. increase RPM.

C. stay the same RPM.

56. Through turbine rotor blades, the pressure.

A. increases, temperature increases, velocity decreases.

B. decreases, temperature and velocity decreases.

C. remains constant, temperature increases.

57. Temperature of the mass airflow through a Gas Turbine Engine.

A. increases from the inlet, through the compressor and the diffuser into the burner, and decreases through the turbine into the exhaust.

B. increases from the inlet, through the compressor and remains constant through the diffuser and increases at the burner, and decreases through the turbine into the exhaust.

C. remains constant at the inlet, increases from the compressor and the diffuser into the burner, and decreases through the turbine into the exhaust.

ABOVE QUESTIONS WITH ANSWERS 

51. Full reverse power is approximately.

A. 95% of forward thrust.

B. 75% of forward thrust.

C. 50% of forward thrust.

Ans : 50% of forward thrust.

52. The efficiency of a gas turbine would be greatest at.

A. cold temperatures.

B. low pressure.

C. hot temperatures

Ans : cold temperatures

Explanation: Maximum thermal efficiency is achieved at the tropopause due to that being the coldest ambient temperature achievable.

53. In a gas turbine engine, turbine section.

A. temperature decreases along with pressure and velocity.

B. velocity decreases and pressure increases.

C. velocity increases and pressure decreases.

Ans : velocity increases and pressure decreases.

Explanation: Pressure and temperature always go down in the turbine as velocity goes up.

54. As air density changes the RPM of a gas turbine engine will change. How is RPM kept at a constant speed?.

A. It is not.

B. Automatically by a simple engine device.

C. Manually by the pilot.

Ans : It is not.

Explanation: Whilst maximum RPM's are limited by various devices RPM is free to wander with changing density. eg As you climb higher minimum idle will increase.

55. With fixed throttle and increasing altitude, the fan on a high by-pass engine will.

A. decrease RPM.

B. increase RPM.

C. stay the same RPM.

Ans : increase RPM.

Explanation: NIL.

56. Through turbine rotor blades, the pressure.

A. increases, temperature increases, velocity decreases.

B. decreases, temperature and velocity decreases.

C. remains constant, temperature increases.

Ans : decreases, temperature and velocity decreases.

Explanation: RR The Jet Engine (4th edition) fig 2-5-1 page 15 (working cycle and airflow).

57. Temperature of the mass airflow through a Gas Turbine Engine.

A. increases from the inlet, through the compressor and the diffuser into the burner, and decreases through the turbine into the exhaust.

B. increases from the inlet, through the compressor and remains constant through the diffuser and increases at the burner, and decreases through the turbine into the exhaust.

C. remains constant at the inlet, increases from the compressor and the diffuser into the burner, and decreases through the turbine into the exhaust.

Ans : increases from the inlet, through the compressor and the diffuser into the burner, and decreases through the turbine into the exhaust.

Explanation: NIL.