Lift and Drag Ratio Relation

Task 1: (P3)

Safety Precaution:

• At first need to be sure that fire extinguisher is available.

• Then Should be ensured that Proper plug in

• Then should be safe of electrical connection.

• Now have clean the wing tunnel.

• Then Bonding and joining of aerofoil should be tightening.

• Should be Wear safety clothis such as insulating shoes, apron and hand gloves.

• Initial lift and drag should be carefully set with the aerofoil.

• Ensure that any obstructions such as human or object is not presented infront of the exhaust of the wing tunnel.

Working procedure:

• At first I have to Change the AOA of the aerofoil.

• Then I have to measure the AOA of the aerofoil.

• Now plug in the wind tunnel and switch is on position.

• Then I have to measure the lift and drag from the scale.

Result and curves:

Test no- 1

Measurement of AOA:

The length of perpendicular is 2.9”

The length of hypotenuse is 11.3”

We know, sin θ = perpendicular/ hypotenuse

= 2.9”/ 11.3”

= 0.2566

So, θ = sin-¹ (0.2566)

= 14.86°

Lift

Upper scale lift: 2 .6kg

Lower scale lift: 9.5 kg

Total lift: 6.9kg.

Drag

Initial drag: 0.6 kg

Final drag: 1.5 kg

Total drag: 0.9 kg

L/D ratio: 6.9/0.9= 7.666

Test no- 2:

AOA: 11.32°

Lift

Upper scale lift: 2.3 kg

Lower scale lift: 8 kg

Total lift: 5.7 kg.

Drag

Initial drag: 0.5 kg

Final drag: 1.5 kg

Total drag: 1 kg

L/D ratio: 5.7 /1= 5.7

There is error on scaling and improper weight balancing. So that graph is not accurate.

Task 2: (M1)

Velocity Vs Lift curves:

At low velocity

Velocity mph – 56.78

Lift- 503 lbs

[pic]

Figure- Velocity mph

At medium velocity

Speed mph – 140.20

Lift- 3072 lbs

[pic]

Figure-Velocity mph

At high velocity...