Day 9 Progress Check

Question 1

Approximately 40-45% of heat is lost through exhaust.

Answer 1

T

Question 2

Which factors can enhance volumetric efficiency in a reciprocating engine?

Answer 2

long intake pipes with small diameters
high carburetor and cylinder-head temperatures
part-throttle operation

Correct: all the above

Question 3

Propulsive efficiency is a ratio of?

Answer 3

thp to bhp

Question 4

Approximately how much heat is used for power output in a reciprocating engine?

Answer 4

Approximately 25-30% of heat is used for power output in a reciprocating engine.

Question 5

Which of these is NOT a factor that enhances thermal efficiency?

Answer 5

using thicker oil.

Question 6

Volumetric Efficiency is expressed as?

Answer 6

%.

Question 7

On average reciprocating aircraft engines reach mechanical efficiency of around?

Answer 7

90%

Question 8

An engine operates lower than 100% volumetric efficiency when?

Answer 8

it draws in less volume than its piston displacement.

Question 9

Extremely high compression ratios aid reciprocating engines with thermal efficiency?

Answer 9

f

Question 10

How much heat is Heat Lost Overcoming Friction in a reciprocating engine?

Answer 10

Around 5-10% of heat is lost in overcoming friction in a reciprocating engine.