Effect Of Temperature On Fly Lab Report

ME2135E Lab Report Flow Past an Aerofoil by LIN SHAODUN
Lab Group Date

A0066078X
2B 10th Feb 2011

TABLE OF CONTENTS

EXPERIMENTAL DATA – TABLE 1, 2, 3

2

GRAPH –

⁄

4

GRAPH –

⁄

5

GRAPH –

6

SAMPLE CALCULATION

7

DISCUSSION

8

1

EXPERIMENTAL DATA

Table 1: Coordinate of Pressure Tapping Tapping No. 1 2 3 4 5 6 7 8 9 10 11 Note: Table 2: Pressure Readings Manometer inclination: Pressure Readings Pitot Pressure Static Pressure Atmospheric Pressure Atmospheric Temperature Stall angle: At the end of the experiment
474 mm 497 mm 500 mm 29°C

(mm)
0.0 2.5 5.0 10 20 30 40 50 60 70 80

(mm)
0.000 3.268 4.443 5.853 7.172 7.502 7.254 6.617 5.704 4.580 3.279 0 0.025 0.049 0.098 0.197 0.295
Tapping 1 2 3 4 5 6 7 8 9 10 11
478 489 494 501 505 506 506 505 502 501 500 496 478 484 492 498 500 502 502 500 499 499 495 475 478 486 494 497 499 500 498 498 498 493 476 475 480 488 493 495 498 496 496 498 486 540 532 528 522 518 516 514 507 503 502 509 562 550 546 526 522 518 514 508 504 502 495 523 520 520 518 517 516 516 515 515 515 498 516 514 515 516 515 514 514 512 513 514

Table 3: Pressure Coefficients

(

)

Free Stream Velocity
√ √ √ ( )

Reynolds Number

3

Coefficients at various

Tapping 1 2 3 4 5 6 7 8 9 10 11
-0.956 -0.478 -0.261 0.043 0.217 0.261 0.261 0.217 0.087 0.043 0.000 -0.174 -0.956 -0.696 -0.348 -0.087 0.000 0.087 0.087 0.000 -0.043 -0.043 0.783 -1.087 -0.956 -0.609 -0.261 -0.130 -0.043 0.000 -0.087 -0.087 -0.087 2.174 -1.043 -1.087 -0.869 -0.522 -0.304 -0.217 -0.087 -0.174 -0.174 -0.087 -0.609 1.739 1.391 1.217 0.956 0.783 0.696 0.609 0.304 0.130 0.087 0.391 2.695 2.174 2.000 1.130 0.956 0.783 0.609 0.348 0.174 0.087 -0.217 1.000 0.869 0.869 0.783 0.739 0.696 0.696 0.652 0.652 0.652 -0.087 0.696 0.609 0.652 0.696 0.652 0.609 0.609 0.522 0.565 0.609

GRAPH

⁄

3.0 2.5 2.0 1.5

CPL , CPU against X/C @ 4°
Cpl

3.0 2.5

CPL , CPU against X/C @ 8°
Cpl Cpu

2.0
1.5
Compare the experimentally measured CL with the Thin Aerofoil Theory prediction of . Discuss the similarity and discrepancy observed. The graph shows at small attack angle (4° and 8°), the measured Lift coefficient is quite close to theoretical predicted value , this is because at small attack angle, air stream flows along the aerofoil surface smoothly without flow separation, which fulfills the basic assumption of Thin Aerofoil Theory, hence the experimental result matches with theoretical value well. When further increase attack angle, the streamline become highly curved, until at certain angle the streamline is no longer attached to the aerofoil surface and flow separation is occurred, massive turbulence wake appears on aerofoil upper surface, which greatly reduce the lift. At this moment aerofoil is actually “blocking” the air flow, hence the Lift coefficient is significantly reduced after reach Stall angle, and can no long follow the theoretical predicted value . 3. What would you expect the lift and drag force to be when At , since the 0015 aerofoil is symmetrical, the pressure on upper and