Lernkarten

Karten 90 Karten 1 Lernende English Andere 08.12.2016 / 08.12.2016 Keine Angabe
0 Exakte Antworten 90 Text Antworten 0 Multiple Choice Antworten

When speed increases in straight and level flight on a positively cambered aerofoil, what happens to the:

I. centre of pressure

II. magnitude of the total lift?

I.    C.P moves aft

II.   remains constant

Assuming no flow effect and no compressibility effects the location of centre of pressure of a positively cambered aerofoil section:

Centre of pressure moves backwards when AoA decreases.

Centre of pressure moves backwards when AoA decreases.

Assuming no flow seperation and no compressibility effects the location of the aerodynamic centre of an aerofoil section:

is independent of angle of attack.

aerodynamic centre is independent of AoA.

Assuming no flow seperation and no compressibility effects the location of the centre of pressure of a symmetrical aerofoil section:

is at approximately 25% chord irrespective* of angle of attack.

*rücksichtslos

centre of pressure of a symmetrical = 25% chord irrespective of AoA.

Assuming no flow seperation and no compressibility effects the location of the
centre of pressure of a symmetrical aerofoil section:

is independent of angle of attack.

centre of pressure of a symmetrical aerofoil section :
is either at approximately 25% chord irrespective of AoA or is independent of AoA!

The lift force acting on aerofoil:
(no flow seperation)

is mainly caused by suction* on the upperside of the aerofoil.

*Absaugung

The lift force acts upperside of the aerofoil because of suction.

Lift is generated when:

the flow dircetion of a certrain mass of air is changed.

see above.

correct statement about the CI and angle of attack:

for a symmetric aerofoil, if angle of attack = 0, CI = 0!

symmetric aerofoil: AoA = 0,    CI = 0.