Test on Reciprocating Engine Induction and Cooling

Question 1: The sodium within an exhaust valve carries heat from the valve stem to the valve head.

A. Ano

B. Ne

Explanation: The study materials state that the sodium picks up heat from the valve head and carries it into the stem, not the other way around.

Question 2: Which of the following best describes the role of molten sodium in an exhaust valve for heat transfer?

A. It remains static to absorb heat from the valve stem and transfer it to the cylinder head.

B. It sloshes up and down, picking up heat from the valve head and carrying it into the stem.

C. It solidifies at high temperatures to create a thermal barrier between the valve head and stem.

D. It vaporizes to cool the cylinder head directly before dissipating into the air.

Explanation: The study material states that the sodium melts when the engine is running and sloshes up and down as the valve operates. It picks up heat from the valve head and carries it into the stem for transfer to the cylinder head.

Question 3: The side of an air-cooled engine cylinder where the exhaust valve is located has the greatest amount of cooling fins.

A. Ano

B. Ne

Explanation: The study materials state that the side of the cylinder in which the exhaust valve is located has the greatest amount of cooling fins.

Question 4: Cowl flaps on a reciprocating engine should be in the closed position when the engine is run on the ground.

A. Ano

B. Ne

Explanation: Cowl flaps should be wide open when operating a reciprocating engine on the ground.

Question 5: What is used in a helicopter to increase the amount of cooling air that flows over the engine cylinders?

A. A turbocharger

B. A belt-driven fan

C. Cowl flaps

D. Blast tubes

Explanation: The study materials indicate that a belt-driven fan is used in a helicopter to increase the amount of cooling air that flows over the engine cylinders.