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Aerodynamics Required Worksheets

40598-12

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Tech-Design

Aerodynamics

Beginning Level Required Worksheets

Second Printing

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BEGINNING LEVEL WORKSHEETS

Atmospheric Data Log Record today’s atmospheric data in the blanks below. Today’s date TEMPERATURE The temperature of the room is _______________ degrees Fahrenheit and _______________ degrees Celsius.

NOTE: To convert degrees Fahrenheit to degrees Celsius, use this formula: [(°F - 32) x 5)] ÷ 9.

PRESSURE The barometric pressure in the room is _______________ inches of mercury (Hg). HUMIDITY The relative humidity in the room is _______________ percent.

4

Windspeed Measurement Activity Worksheet NAME __________________________________ DATE ___________________ Record your answers below: Wind Speed Adjuster (1 inch) ________ MPH Wind Speed Adjuster (4 inches) ________ MPH Wind Speed Adjuster (6 inches) ________ MPH

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Lift and Bernoulli’s Principle Worksheet NAME __________________________________ DATE ___________________ Record your results below: AIRFOIL A Wind speed: _____________ MPH Lift meter reading: ____________ grams Due to the shape of airfoil A, it should not generate any significant lift at any given wind speed. AIRFOIL B Wind speed: _____________ MPH Lift meter reading: ____________ grams NOTE: If you measure any positive or negative lift using airfoil B, then the angle of attack adjustment is not zeroed properly. Based on your test results, what can you conclude about the aerodynamics of airfoil A and airfoil B? Which airfoil creates more lift? Record your answer in the space provided. The airfoil that creates more lift is: ____________________.

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Drag Worksheet NAME __________________________________ DATE ___________________ Record your results below: CAR A Wind speed: _____________ MPH Drag meter reading: ____________ grams CAR B Wind speed: _____________ MPH Drag meter reading: ____________ grams The car that has less drag is: ____________________.

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Angle of Attack Worksheet NAME __________________________________ DATE ___________________ Record your results below: ANGLE OF ATTACK = 0 Wind speed: __________ MPH Lift meter reading: _________ grams ANGLE OF ATTACK = +5 Wind speed: __________ MPH Lift meter reading: _________ grams ANGLE OF ATTACK = +7.5 Wind speed: __________ MPH Lift meter reading: _________ grams ANGLE OF ATTACK = +10 Wind speed: __________ MPH Lift meter reading: _________ grams As the angle of attack increases, the lift _____________.

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Atmospheric Data Summary Report Using the information from the daily logs, complete the report: 1. Highest temperature was _______________ °F, _______________ °C recorded on

_______________ (date). 2. Lowest temperature was _______________ °F, _______________ °C recorded on

_______________ (date). 3. Average temperature for the time period covered was _______________ °F,

_______________ °C. (Remember to calculate an average, add all the daily temperature readings and divide by the number of items added.)

4. Highest barometric pressure was _______________ inches of mercury (Hg)

recorded on _______________ (date). 5. Lowest barometric pressure was _______________ inches of mercury (Hg)

recorded on _______________ (date). 6. Average barometric pressure for the time period covered was _______________

inches of mercury (Hg). 7. Highest relative humidity was _______________ percent. 8. Lowest relative humidity was _______________ percent. 9. Average relative humidity for the time period covered was _______________

percent. 10. Was there a wide spread in the various readings or were the readings all within a

small range?

11. Did you see any trends in the log records? If so, what were they?

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12. Is there a relationship between the various readings? If so, what is it?

13. What effect do you think changes in atmospheric conditions might have in

aerodynamic performance? Explain your answer.

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Tech-Design

Aerodynamics

Advanced Level Required Worksheets

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ADVANCED LEVEL WORKSHEETS

Lift and Drag Coefficients Activity Worksheet

LIFT COEFFICIENT

TUNNEL DATA The airspeed for the first part of the experiment is . LIFT METER READINGS

AIRFOIL A Angle

(degrees) Lift

(grams) Lift

(kg) *

0 2.5 5

7.5 10

AIRFOIL B Angle

(degrees) Lift

(grams) Lift

(kg) *

0 2.5 5

7.5 10

* Divide each value by 1000 to get kilograms.

12

CALCULATING THE LIFT COEFFICIENT Calculate the lift coefficient for each meter reading by dividing each value by the dynamic pressure and the surface area. Dynamic pressure: Calculate the dynamic pressure using ρ = 1.225 kg/m3.

The dynamic pressure is 12

12

2ρV = ( )( )2 = .

Where: ρ = density of air in kilograms per cubic meter. V = velocity of air in meters per second.

NOTE: V must be in meters

sec. To convert

mileshr

to meters

sec

multiply by 0.447. Surface area: Calculate the surface area of each airfoil. Be sure to calculate your

answer in square meters or convert your answer to square meters.

The surface area of Airfoil A is (length x width x 2) sq. meters. The surface area of Airfoil B is (length x width x 2) sq. meters.

LIFT COEFFICIENT Calculate the lift coefficient for each airfoil at the specified angle of attack. Each reading is multiplied by a drag factor to eliminate the drag force from the balance.

AIRFOIL A ANGLE

OF ATTACK

LIFT READING

(KG)

DIVIDED BY DYNAMIC PRESSURE

DIVIDED BY SURFACE

AREA

EQUALS LIFT

COEFFICIENT 0

2.5

5

7.5

10

13

AIRFOIL B

ANGLE OF

ATTACK

LIFT READING

(KG)

DIVIDED BY DYNAMIC PRESSURE

DIVIDED BY SURFACE

AREA

EQUALS LIFT

COEFFICIENT 0

2.5

5

7.5

10

On a single sheet of graph paper, graph your results. Use the x axis (along the bottom) for angle of attack. Use the y axis (the vertical axis on the left) for coefficient of lift. Use a different color pen or pencil for each model tested in the wind tunnel. Don’t forget to put a key on your graph which tells which color represents what model. DRAG COEFFICIENT Calculate the drag coefficient of each of the two cars using the table provided.

DRAG METER

READING

DIVIDED BY DYNAMIC

PRESSURE

DIVIDED BY SURFACE AREA

EQUALS DRAGCOEFFICIENT

CAR 1

.00204 m2

CAR 2

.00169 m2

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Sample Data – Lift and Drag Coefficient Activity LIFT METER READINGS (Wind Speed 35 mph)

Airfoil A Airfoil B Angle

(degrees) Lift

(grams) Lift (kg)

Angle (degrees)

Lift (grams)

Lift (kg)

0 0 0 0 27 .027 2.5 22 .022 2.5 46 .046 5.0 44 .044 5.0 67 .067 7.5 65 .065 7.5 90 .090

10.0 81 .081 10.0 112 .112

Dynamic Pressure: ½ ρV2 = 0.5 (1.225)(15.645)2 = 150 kg

m s2•

SURFACE AREA Airfoil A Airfoil B L x W x 2 L x W x 2 (.127) (.0762) (2) = 0.0194 m2 (.127) (.0825) (2) = 0.0210 m2 COEFFICIENTS OF LIFT (calc)

Airfoil A Airfoil B Angle (degrees) CL Angle (degrees) CL

0 0 0 0.00857 2.0 0.00756 2.5 0.01460 5.0 0.01512 5.0 0.02127 7.5 0.02234 7.5 0.02857 10.0 0.02784 10.0 0.03556

CONVERSION OF MILES PER HOUR TO METERS PER SECOND 1 mi

hr x

5280 ftmi

x 12 in.

ft x

1 meter39.37 in.

x 1 hr

3600 s = 0.447

meterss

mihr

x 0.447 = meters

ondsec

NOTE: Student data will vary.

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Zero Lift Angle of Attack Worksheet NAME __________________________________ DATE ___________________ Record your results below: ANGLE OF ATTACK: ______ degrees LIFT METER READING: ______ grams ANGLE OF ATTACK: ______ degrees LIFT METER READING: ______ grams ANGLE OF ATTACK: ______ degrees LIFT METER READING: ______ grams ANGLE OF ATTACK: ______ degrees LIFT METER READING: ______ grams ANGLE OF ATTACK: ______ degrees LIFT METER READING: ______ grams ANGLE OF ATTACK: ______ degrees LIFT METER READING: ______ grams ANGLE OF ATTACK: ______ degrees LIFT METER READING: ______ grams ANGLE OF ATTACK: ______ degrees LIFT METER READING: ______ grams ANGLE OF ATTACK: ______ degrees LIFT METER READING: ______ grams ANGLE OF ATTACK: ______ degrees LIFT METER READING: ______ grams The zero lift angle of attack is ________.

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Airfoil Design Worksheet NAME __________________________________ DATE ___________________ Record the important facts about your airfoil in the spaces provided. What will your airfoil be used for? ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ Will the leading edge be blunt or sharp? ________________________________________________________________ Will your airfoil be symmetrical or asymmetrical? ________________________________________________________________ If it is cambered, will the camber be positive or negative? ________________________________________________________________ How long will the chord be? ________________________________________________________________ What will the maximum thickness be and where will it occur? ________________________________________________________________

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Viscosity Worksheet NAME __________________________________ DATE ___________________ Record your results below: The water took _______ seconds to drain out of the tube. The oil took _________ seconds to drain out of the tube. Which fluid has the higher viscosity? ______________________ .

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Tech-Design

Aerodynamics

Comprehensive Level Required Worksheets

19

COMPREHENSIVE LEVEL WORKSHEETS

Atmospheric Data Log Record today’s atmospheric data in the blanks below. Today’s date TEMPERATURE The temperature of the room is _______________ degrees Fahrenheit and _______________ degrees Celsius.

NOTE: To convert degrees Fahrenheit to degrees Celsius, use this formula: [(°F - 32) x 5)] ÷ 9.

PRESSURE The barometric pressure in the room is _______________ inches of mercury (Hg). HUMIDITY The relative humidity in the room is _______________ percent.

20

Windspeed Measurement Activity Worksheet NAME __________________________________ DATE ___________________ Record your answers below: Wind Speed Adjuster (1 inch) ________ MPH Wind Speed Adjuster (4 inches) ________ MPH Wind Speed Adjuster (6 inches) ________ MPH

21

Lift and Bernoulli’s Principle Worksheet NAME __________________________________ DATE ___________________ Record your results below: AIRFOIL A Wind speed: _____________ MPH Lift meter reading: ____________ grams Due to the shape of airfoil A, it should not generate any significant lift at any given wind speed. AIRFOIL B Wind speed: _____________ MPH Lift meter reading: ____________ grams NOTE: If you measure any positive or negative lift using airfoil B, then the angle of attack adjustment is not zeroed properly. Based on your test results, what can you conclude about the aerodynamics of airfoil A and airfoil B? Which airfoil creates more lift? Record your answer in the space provided. The airfoil that creates more lift is: ____________________.

22

Drag Worksheet NAME __________________________________ DATE ___________________ Record your results below: CAR 1 Wind speed: _____________ MPH Drag meter reading: ____________ grams CAR 2 Wind speed: _____________ MPH Drag meter reading: ____________ grams The car that has less drag is: ____________________.

23

Angle of Attack Worksheet NAME __________________________________ DATE ___________________ Record your results below: ANGLE OF ATTACK = 0 Wind speed: __________ MPH Lift meter reading: _________ grams ANGLE OF ATTACK = +5 Wind speed: __________ MPH Lift meter reading: _________ grams ANGLE OF ATTACK = +7.5 Wind speed: __________ MPH Lift meter reading: _________ grams ANGLE OF ATTACK = +10 Wind speed: __________ MPH Lift meter reading: _________ grams As the angle of attack increases, the lift _____________.

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Atmospheric Data Summary Report Using the information from the daily logs, complete the report: 14. Highest temperature was _______________ °F, _______________ °C recorded on

_______________ (date). 15. Lowest temperature was _______________ °F, _______________ °C recorded on

_______________ (date). 16. Average temperature for the time period covered was _______________ °F,

_______________ °C. (Remember to calculate an average, add all the daily temperature readings and divide by the number of items added.)

17. Highest barometric pressure was _______________ inches of mercury (Hg)

recorded on _______________ (date). 18. Lowest barometric pressure was _______________ inches of mercury (Hg)

recorded on _______________ (date).

19. Average barometric pressure for the time period covered was _______________ inches of mercury (Hg).

20. Highest relative humidity was _______________ percent. 21. Lowest relative humidity was _______________ percent. 22. Average relative humidity for the time period covered was _______________

percent. 23. Was there a wide spread in the various readings or were the readings all within a

small range?

24. Did you see any trends in the log records? If so, what were they?

25

25. Is there a relationship between the various readings? If so, what is it?

26. What effect do you think changes in atmospheric conditions might have in

aerodynamic performance? Explain your answer.

26

Lift and Drag Coefficients Activity Worksheet

LIFT COEFFICIENT TUNNEL DATA The airspeed for the first part of the experiment is . LIFT METER READINGS

AIRFOIL A Angle

(degrees) Lift

(grams) Lift

(kg) *

0 2.5 5

7.5 10

AIRFOIL B Angle

(degrees) Lift

(grams) Lift

(kg) *

0 2.5 5

7.5 10

* Divide each value by 1000 to get kilograms.

27

CALCULATING THE LIFT COEFFICIENT Calculate the lift coefficient for each meter reading by dividing each value by the dynamic pressure and the surface area. Dynamic pressure: Calculate the dynamic pressure using ρ = 1.225 kg/m3.

The dynamic pressure is 12

12

2ρV = ( )( )2 = .

Where: ρ = density of air in kilograms per cubic meter. V = velocity of air in meters per second.

NOTE: V must be in meters

sec. To convert

mileshr

to

meterssec

multiply by 0.447.

Surface area: Calculate the surface area of each airfoil. Be sure to calculate your answer in square meters or convert your answer to square meters.

The surface area of Airfoil A is (length x width x 2) sq. meters.

The surface area of Airfoil B is (length x width x 2) sq. meters. LIFT COEFFICIENT Calculate the lift coefficient for each airfoil at the specified angle of attack. Each reading is multiplied by a drag factor to eliminate the drag force from the balance.

IRFOIL A ANGLE

OF ATTACK

LIFT READING

(KG)

DIVIDED BY DYNAMIC PRESSURE

DIVIDED BY SURFACE

AREA

EQUALS LIFT

COEFFICIENT 0

2.5

5

7.5

10

28

AIRFOIL B ANGLE

OF ATTACK

LIFT READING

(KG)

DIVIDED BY DYNAMIC PRESSURE

DIVIDED BY SURFACE

AREA

EQUALS LIFT

COEFFICIENT 0

2.5

5

7.5

10

On a single sheet of graph paper, graph your results. Use the x axis (along the bottom) for angle of attack. Use the y axis (the vertical axis on the left) for coefficient of lift. Use a different color pen or pencil for each model tested in the wind tunnel. Don’t forget to put a key on your graph which tells which color represents what model. DRAG COEFFICIENT Calculate the drag coefficient of each of the two cars using the table provided.

DRAG METER

READING

DIVIDED BY DYNAMIC

PRESSURE

DIVIDED BY SURFACE AREA

EQUALS DRAGCOEFFICIENT

CAR 1

.00204 m2

CAR 2

.00169 m2

29

Sample Data – Lift and Drag Coefficient Activity LIFT METER READINGS (Wind Speed 35 mph)

Airfoil A Airfoil B Angle

(degrees) Lift

(grams) Lift (kg)

Angle (degrees)

Lift (grams)

Lift (kg)

0 0 0 0 27 .027 2.5 22 .022 2.5 46 .046 5.0 44 .044 5.0 67 .067 7.5 65 .065 7.5 90 .090

10.0 81 .081 10.0 112 .112

Dynamic Pressure: ½ ρV2 = 0.5 (1.225)(15.645)2 = 150 kg

m s2•

SURFACE AREA Airfoil A Airfoil B L x W x 2 L x W x 2 (.127) (.0762) (2) = 0.0194 m2 (.127) (.0825) (2) = 0.0210 m2 COEFFICIENTS OF LIFT (calc)

Airfoil A Airfoil B Angle (degrees) CL Angle (degrees) CL

0 0 0 0.00857 2.0 0.00756 2.5 0.01460 5.0 0.01512 5.0 0.02127 7.5 0.02234 7.5 0.02857 10.0 0.02784 10.0 0.03556

CONVERSION OF MILES PER HOUR TO METERS PER SECOND 1 mi

hr x

5280 ftmi

x 12 in.

ft x

1 meter39.37 in.

x 1 hr

3600 s = 0.447

meterss

mihr

x 0.447 = meters

ondsec

NOTE: Student data will vary.