AE303 – Lab 5: DC-6B Fredy Gomez Cruz, 821602191 San Diego State University, San Diego, CA, 92115 The purpose of this lab was to measure the aerodynamic forces on an Model airplane DC-6B using wind tunnel force measurements. Measuring the force values from the model we are able to find the forces of lift, drag and the aerodynamic pitching and yawing moments. Using the wind tunnel, we are able to determine aerodynamic force. Most importantly the purpose of this experiment was the variation of this data when the tail of the model was on and off. We first set up the experiment by placing the model DC-6B into the wind tunnel and measuring the drag, lift and moment forces at 10 distinctive angles. Using the SDSU wind tunnel at a constant velocity and dynamic pressure we were able to gather data from this experiment. This experiment was highly beneficial when understanding the relation of angle of attack versus lift and drag and the relation between moments and the yawing and pitch angles. I learned from this experiment that the coefficient of drag increased with the increased angle of attack. This seemed to increase further when the tail was attached to the model. Interesting enough the lift coefficient also increased when the tail was attached. This makes sense as the tail serves to increase stability and increase efficiency. The vital information extracted from this lab was the forces on the model and how the angle of attack changed the performance of the model. Results presented and increase in the lift coefficient with the tail attached, an increase in stability presented through an increase pitching moment coefficient. Also an increase in yaw moment coefficients when the angle of yaw increase. However, when the tail was attached the stability of the airfoil grew. While the airfoil seemed to be more aerodynamic without the tail, ultimately the tail serves to be a stabilizer of the model to produce a more aerodynamic model overall. Nomenclature π S b π πΆπ πΆπ πΆπΏ πΆπ· e AR π₯ π¦ π£ π πΌ = chord length = Area of Airfoil = wing span = Dynamic Pressure = Pitching Moment Coefficient = Yaw Moment Coefficient = Lift = Drag = Oswald Efficiency = Aspect Ratio = Distance Along the Chord Line = Coordinate Perpendicular to Chord Line = Velocity of the Air Flow Upstream of the Airfoil = Density = Angle of Attack ᡦ = Angle of Yaw πΉπ₯ πΉπ¦ πΉπ§ ππ₯ ππ¦ ππ§ = Drag Force = Side Force = Lift Force = Rolling Moment =Pitching Moment =Yawing Moment 1 American Institute of Aeronautics and Astronautics Introduction The goal of this experiment was to measure the aerodynamic forces of a model using the wind tunnel force measurements. The wind tunnel aerodynamic forces allows the investigation of aerodynamic forces, the change in them when the angle of attack changes and then the effect of these changes when the airfoil has a tail and when it doesn’t. This experiment was performed in the SDSU wind tunnel with the proper lab safety technique. First the airfoil is placed at a -6-degree angle of attack and a velocity is set. At this point the wind tunnel will begin to measure forces on a model placed inside the wind tunnel. Having multiple angles of attack will allow for the analysis of the most accurate data. The data collected from the experiment will allow us to find the relationship of the change in angle of attack and yaw angle on the coefficients of lift, drag and moments. Using two data group, one where the model has a tail and more where the model does not, we will also be able to analyze which setting is the most effective at reducing drag while increasing lift. The data will then be compared and the relationship between the coefficient of lift versus angle of attack will be analyzed when the tail is on and off to determine which is more efficient. The same analysis will be applied with the yaw moment and the yaw angle. Theory First the lift, drag, pitching moment and yaw moment are measured by the wind tunnel. For each force and moment, F, are provided a equation that allows for the forces of just the model to be presented: F(model) = [F(model on, wind on) – F(model on, wind off)] – [F(model off, wind on) – F(model off, wind off)] The equation provides the ability to remove the influence of the shafts on the overall performance of the model. Using the several measurements of the forces of lift, drag, pitching moment and yaw moment. These forces are then used to find the coefficients of lift and drag. The forces measured by the wind tunnel also calculate the pitching moment coefficient and the yaw moment coefficient. πΏ ππ = ππ (1) π· (2) πΆπ· = ππ πΆπ = πππΜ πΆπ = πππ ππ¦ (3) : π (4) Finally, the Oswald Coefficient was also discovered using the aspect ration of the airfoil. The aspect ratio is plugged into the equation and is able to account into the Oswald efficiency factor. The Oswald efficiency is important because it helps calculate the efficiency factor for the straight wing aircraft with data such as the span, area of the wing and chordline. The Oswald efficiency is used to interpret the change in drag with lift for a airfoil area. β = 1.78(1 − .045π΄π .68 ) − 0.64 (6) Procedure This procedure dictates the steps necessary to perform this experiment correctly. This experiment was not performed by a different group and data was presented for students to analyze. General Experiment Procedure ο· ο· ο· Read Barometer and Temperature Zero the balance system such that yaw angle and Angle of Attack are at 0 degrees respectively. Assure that the model is on and the wind is off 2 American Institute of Aeronautics and Astronautics ο· ο· Record dynamic pressure, temperature and forces and moment for the angles of attack: o πΌ =[ -6 -4 -2 0 2 4 6 8 10 15] o ᡦ = [0 5 10] Complete 6 run with the following 5 iteration and repeat the steps above o Model On, Tail On, Wind Off o Model On, Tail On, Wind On o Model On, Tail Off, Wind On o Model Off, Tail Off, Wind On o Model Off, Tail Off, Wind Off Equipment ο· ο· ο· ο· San Diego State University Subsonic Wind Tunnel o Constructed 1963 o Range: 0-180 mph o TF : 1.27 o 150 Hp o 6-Load Cell Strain Gauge Balance System 2.2 Full Model Airplane: DC-6B o Model reference area S = 93.81 in. 2 o Model reference length c = 3.466 in. o Model reference wing span b = 27.066 in. 2.3 Wind tunnel test setting o Free stream dynamic pressure q = 7 in H2O Computer Results and Discussion The results presented below are the result of the coefficients of lift, coefficients of drag and the pitching and yaw moment. This data was gathered separate from the student body and all results presented are the analysis component of measured data. Results presented showcase a similar shape in curve when comparing figure (1) and figure (2) data. This result is important because it showcases that both models have similar behaviors. However, even though the model with the tail on presents a higher ration of lift to drag meaning that it creates more drag, that it also manages to create more lift. Figure 2 showcases similar behaviors when the angle of attack increases. The model with and without the tail follow the same behavior and after the critical angle of attack, lift decreases. Both lines showcase this behavior. The model with the tail, has a higher coefficient of lift than the model without the tail. This means that the tail is able to create more stability while also being able to assist in the increase of the coefficient of lift. Figure 1: Coefficient of Lift v Coefficient of Drag 3 American Institute of Aeronautics and Astronautics Figure 2: Coefficient of Lift v AoA The results below showcase the Yawing moment coefficient versus the yaw angle, and the pitching moment coefficient versus the angle of attack. In Figure 1, a positive slope indicates that the model is stable. In the graph the yawing moment coefficient is reaching a positive slope as opposed to the negative slope that is presented with the tail off results, this means that the yawing moment is more stable when the tail is attached to the model. When the tail is not attached to the model there is less stability in the model. Furthermore, there is the pitching moment coefficient versus the angle of attack. The pitch coefficient is what prevents pitch moment when the model experiences a high clockwise moment. When the pitching moment increases a positive slope means that the model increasingly becomes more unstable. This instability is not noticeable when it comes to the tail on because the pitching moment coefficient decreases when the angle of attack increases. This decrease in the pitching moment coefficient means that as the angle of attack increases that the pitching momement decreases. This creates a more stable aircraft. Having a lower pitching coefficient when angle of attack increases creates a more stable aircraft at higher angles of attack. The opposite behavior is seen with the tail off. This means that as the angle of attack increases that instead of decreasing pitching moment, it also increases further increase destabilization. Figure 3: Yawing Moment Coefficient v Yaw Angle Figure 4: Pitching Moment Coeff v AoA The results presented above showcase the behaviors of a model with and without its tail and the effects that is has on the lift, drag, pitch and yaw moments. The results supported the idea that the tail serves as both an stabilizer and increases the lift to drag ratio The results clearly support the idea that the tail increases the overall efficiency of the airfoil Furthermore, as seen by the last two figures, the tail serves to increase the performance of stabilization when the aircraft experiences yaw and pitching moments. Results undeniably support the model performance increases when the tail is attached. Lab 5: Full Model Aircraft Performance TITLE Oswald Efficiency TITLE Maximum Lift-to-Drag Ratio Zero-lift Angle of Attack Lift-Curve Slope Maximum Lift Coefficient VAR π VAR (πͺπ³ /πͺπ« )πππ (πͺπ³ /πͺπ« )πππ πΆπ³=π πΆπ³=π π πͺπ³ /π πΆ π πͺπ³ /π πΆ (πͺπ³ )πππ (πͺπ³ )πππ Tail Config. On Off On Off On Off On Off 4 American Institute of Aeronautics and Astronautics VALUE .81596 VALUE 12.384 13.134 3.75 3.9 .075 .062 .932 .832 UNITS UNITS π πππππ π πππππ π πππππ−π π πππππ−π - Critical Angle of Attack Pitching Moment-Curve Slope Yawing Moment-Curve Slope TITLE VAR UNITS VALUE TITLE VAR UNITS VALUE Angle of Attack πΆ −6 -4 -2 0 2 4 6 8 10 15 Coeff. of Lift πͺπ³ -0.23818 -0.06064 0.11797 0.30554 0.49023 0.68005 0.82162 0.93212 0.83309 0.77552 Sideslip Angle π· 0 5 10 πΆππππππππ πΆππππππππ π πͺπ΄ /π πΆ π πͺπ΄ /π πΆ π πͺπ΅ /π π· π πͺπ΅ /π π· On Off On Off On Off Tail ON Coeff. of Pitching Moment πͺπ΄ 0.19291 0.12505 0.07557 0.0300 -0.01345 -0.06913 -0.12113 -0.16732 -0.39494 -0.53298 Coeff. of Drag 8 8 -.0322 .0169 .0022 -8.6305E-4 Coeff. of Lift πͺπ« 0.06724 0.05332 0.04755 0.04797 0.04781 0.05632 0.06256 0.07527 0.16388 0.31825 Tail ON Yawing Moment Coefficient (πͺπ΅ )ππππ ππ 0.00287 0.00429 0.02477 πͺπ³ -0.17100 -0.01638 0.14308 0.28554 0.46555 0.62891 0.74434 0.83202 0.66823 0.58263 Tail OFF Coeff. of Pitching Moment πͺπ΄ -0.10679 -0.04159 0.00121 0.05377 0.09936 0.14172 0.17762 0.21223 0.16165 0.16689 π πππππ π πππππ π πππππ−π π πππππ−π π πππππ−π π πππππ−π Coeff. of Drag πͺπ« 0.05784 0.04837 0.04327 0.04077 0.03939 0.04506 0.05028 0.06324 0.15150 0.27136 Tail OFF Yawing Moment Coefficient (πͺπ΅ )ππππ πππ -0.00131 -.00541 -.00809 Conclusion The purpose of this lab experiment was to compare the forces on an on the model DC-6B from a wind tunnel when the tail is attached and when there is no tail. Most importantly the aerodynamic force on the model provided information of the coefficient of lift drag and yawing and pitching moment. These aerodynamic forces were compared when testing the behavior of the model with and without its tail. The results showcased the relationship between a coefficient of lift and the angle of attack , the ratio of lift and drag and the yaw and pitching moments versus the yaw and pitch angles respectively. The results presented the difference in these changes with the model when it had a tail attached and no tail. The results showcase that there was an increase in stability, lift, drag and overall efficiency when a tail was on. In conclusion, the data supported the idea that the tail improves the overall efficiency of the performance of the model. The wind tunnel first measured the aerodynamic forces of the model. Using the data gathered from the force measurements, the calculations for the coefficients of lift, drag yaw and pitching moment were derived in order to determine the behavior of a model in a wind tunnel at different angles of attack and yaw angles with the tail on and the tail off. We obtained a better understanding of airplane aerodynamic performance through the analysis of these forces with respect to the change in angle of attack. The theories presented in previous classes supported the behaviors of the model as the tail served to provide stability and increase effectiveness. The theories state that the tail is used for stability and even though it may increase drag that it is also a factor in increasing lift. Figure 1 strongly supported this claim because the lift to drag was greater with the tail on than 5 American Institute of Aeronautics and Astronautics the tail. This figure displayed that the lift and the drag was greater in the test with the tail on. Theories also explained the tail helped with yaw stability. These results were supported through Figure 3 as the tail increased the Yaw Moment coefficient as the angle of yaw increased. This means that the tail is actively preventing a yaw moment that would destabilize the airplane. Overall, the results supported the theories presented our courses. Some ways that this experiment could be improved is to be able to find shafts that will provide even less effects on our results, The fact that the struts may be affecting the experiment can create some artificial drag that may not be created by the airplane. A big factor of error in the experiment is also the fact that no students were able to participate and perform the lab. This means we are at the mercy of the data and factors such as debris inside of the wind tunnel or an incorrect dynamic pressure may affect the results. This data as far as we know is the most correct or can also be full of errors. Finally the results may have suffered from skewed answers if the balance was not properly zeroed out. This may increase drag and yaw moment without the testers of the experiment ever noticing. Sample Calculations Temperature Correction: Y1=72 Y=76.5 Y2=76 ππππ = = X1=29 0.114 Latitude Correction: X=29.75 X2=30 0.118 Y1=32 Y=32.7157 Y2=34 P1 0.124 0.128 X1=29 0.035 X X2=30 0.036 P2 0.030 0.031 (π₯2 − π₯)(π¦2 − π¦) (π₯ − π₯1 )(π¦2 − π¦) (π₯2 − π₯)(π¦ − π¦1 ) (π₯ − π₯1 )(π¦ − π¦1 ) π + π + π + π (π₯2 − π₯1 )(π¦2 − π¦1 ) 11 (π₯2 − π₯1 )(π¦2 − π¦1 ) 21 (π₯2 − π₯1 )(π¦2 − π¦1 ) 12 (π₯2 − π₯1 )(π¦2 − π¦1 ) 22 (π₯2 − π₯)(π¦2 − π¦) (π₯ − π₯1 )(π¦2 − π¦) (π₯2 − π₯)(π¦ − π¦1 ) (π₯ − π₯1 )(π¦ − π¦1 ) π11 + π21 + π12 + π = (π₯2 − π₯1 )(π¦2 − π¦1 ) (π₯2 − π₯1 )(π¦2 − π¦1 ) (π₯2 − π₯1 )(π¦2 − π¦1 ) (π₯2 − π₯1 )(π¦2 − π¦1 ) 22 ππππ = 29.567 πππ»π Corrected Pressure in (psi) Scanivalve: ππππ = 29.567 πππ»π ∗ 0.491154ππ π = 14.522ππ π 1 πππ»π Density: ππππ π= = π π 29.567πππ»π ∗ 3386.39 ππ 1 πππ»π 5 287 ∗ (76.5β + 459.17 ∗ ( )) 9 = 1.057 ππ π3 Velocity: 248.84 ππ 2 (( 7πππ»2π) × ) 1πππ»2π 2π √ π π=√ = = 57.40 ππ π π 1.057 3 π Sutherland Equation: Dynamic Viscosity 6 American Institute of Aeronautics and Astronautics π= ππ 1β2 π π (1+ ) = 1.458×106 πΎπ π⋅π ⋅πΎ1β2 5 9 (76.5β+459.17∗( )) 1β2 = 1.835 × 10−5 110.4πΎ ) 5 (76.5β+459.17∗(9)) (1+ Reynold’s Number: ππ π ππ£π 1.057 π3 × 57.40 π × 0.0880364π π β = = = 2.91 × 105 π 1.835 π₯10−5 Coefficient of Lift: πΆπΏ = πΏ −5.6448 = = −.23818 ππ 7πππ»2π × 93.81ππ2 Coefficient of Drag: πΆπ· = π· 1.5936 = = .06724 ππ 7πππ»2π × 93.81ππ2 Pitching Moment Coefficient : πΆπ = ππ¦ 15.8464 = = .19291 πππΜ 7πππ»2π × 93.81ππ2 × 3.466ππ Yaw Moment Coefficient: πΆπ = π 1.0675 = = .00166 πππ 7πππ»2π × 93.81ππ2 × 27.066ππ Aspect Ratio: π΄π = π 2 27.066ππ2 = = 7.8091 π 93.81ππ2 Oswald Efficiency: β = 1.78(1 − .045π΄π .68 ) − 0.64 = 1.78(1 − .045(7.8091.68 ) − 0.64 = .81596 Lift Slope: ππΆπΏ π¦2 − π¦1 . 49023 − .30554 = = = .0923 ππΌ π₯2 − π₯1 2−0 Acknowledgments This lab was under the supervision of Dr. Xiaofeng Liu and laboratory teaching assistant Nate Abrenilla. A lecture was prepared and delivered by Dr. Liu who guided the class towards producing the statistical results of this lab. Lab technician Nate Abrenilla overlooked the data readings. This lab was performed at SDSU facilities and results were produced through numerical analysis at home. References [1] Figliola and Beasley, 6th Ed., 2015 [2] Latitude Correction, (n.d.). [online] Available at: https://blackboard.sdsu.edu/bbcswebdav/pid-5431224-dtcontent-rid108216837_1/courses/A_E303-01-Spring2020/LattitudeCorrectionForBarometerHeightReading.pdf [3] Temperature Correction, (n.d.). [online] Available at: https://blackboard.sdsu.edu/bbcswebdav/pid-5431224-dtcontent-rid108216837_1/courses/A_E303-01-Spring2020/TemperatureCorrectionForBarometerHeightReading.pdf [4] Liu, X. (n.d.). AE 303 Experimental Aerodynamics: Lecture 2. 7 American Institute of Aeronautics and Astronautics Appendix A Proof: F(model) = [F(model on, wind on) – F(model on, wind off)] – [F(model off, wind on) – F(model off, wind off)] F(model) = [F(model) + F(struts)] – [F(struts)] F(model) = F(model) Given the following equations, we are asked to prove that the Aerodynamic forces on the model equate to the difference of two forces. The forces on a model with a wind tunnel on minus the forces of on a model with the wind tunnel off and the forces on two support shafts with the wind tunnel on minus the forces on two shafts minus with the wind tunnel off. Both parts of the equation present the aerodynamic forces on the model being experimented on. The results of the first array will present the aerodynamic forces on a model as well in addition to the aerodynamic forces on the shafts that are holding the model in place. The results on the second array part of the equation will be the aerodynamic forces on two supporting shafts. When subtracting these arrays, it is proved that the only forces being calculated will be the aerodynamic forces of the model which are the complete aerodynamic forces being measured. 8 American Institute of Aeronautics and Astronautics Appendix B Raw Data: Model on Tail on Wind off VAR UNITS a (deg) -6 -4 -2 0 2 4 6 8 10 15 0 0 b (deg) 0 0 0 0 0 0 0 0 0 0 5 10 T (deg F) 72.3 72.3 72.3 72.3 72.3 72.3 72.3 72.3 72.3 72.3 72.3 72.3 Fx Fy Fz Mx My Mz (lbs) -0.005908 0.017053 -0.004624 -0.015708 0.001453 -0.027536 -0.022835 -0.018871 -0.008925 -0.028839 -0.165008 -0.01854 (lbs) 0.018442 0.01273 0.032428 0.01016 0.018352 0.004237 0.02523 0.014524 -0.005993 -0.025351 -0.36162 -0.059068 (lbs) 0.088777 0.00262 0.056704 -0.000327 0.034289 0.070536 -0.068748 -0.080231 0.036908 0.064041 -0.006624 0.112114 (lbs-in) 0.244822 0.501834 0.786183 0.891143 0.829477 0.967714 0.228854 0.939119 1.110047 0.342711 -21.97348 -32.66918 (lbs-in) -2.022044 -0.113281 -0.353426 0.182135 -0.209594 0.419119 0.996239 1.732817 1.466205 2.223806 7.012855 8.128888 (lbs-in) -0.184967 -0.47868 -0.28054 -0.36136 -0.402864 -0.477849 -0.090122 0.220062 0.046479 0.819693 6.294042 2.020689 Model on Tail on Wind on VAR UNITS WIND OFF a (deg) 0 -6 -4 -2 0 2 4 6 8 10 15 0 0 b (deg) 0 0 0 0 0 0 0 0 0 0 0 5 10 T (deg F) 80.4 84.6 85.4 86 86.6 87.2 87.7 88.5 89 89.7 90.1 91.1 91.3 Fx Fy Fz Mx My Mz (lbs) 0.026864 7.194787 6.872995 6.70594 6.720269 6.738783 6.922296 7.088431 7.382709 9.485697 13.18478 6.876539 7.396124 (lbs) -0.044216 -0.727597 -0.682756 -0.776686 -0.809907 -0.8867 -0.929877 -0.866889 -0.904505 -0.67123 -0.560931 -4.703029 -10.19293 (lbs) 0.126754 -4.404358 -0.277936 4.027154 8.362796 12.72379 17.34721 20.57334 23.20206 20.92874 19.49249 8.462686 8.582788 (lbs-in) -0.657393 1.024059 2.924975 2.127815 1.409047 -0.099865 0.673774 0.622432 0.021775 -6.206694 -18.03564 -30.55221 -67.04751 (lbs-in) 0.280259 -37.0396 -41.57501 -45.48488 -49.73383 -53.56722 -57.82892 -61.61265 -64.92059 -83.36735 -95.43278 -44.14704 -39.30335 (lbs-in) -0.416469 -0.253064 -0.145788 -0.204641 -0.009391 0.312847 0.090355 0.205982 0.104649 0.571622 0.740256 12.63188 13.97878 Model on Tail off Wind on VAR UNITS WIND OFF a (deg) 0 -6 -4 -2 0 2 4 6 8 10 15 0 0 b (deg) 0 0 0 0 0 0 0 0 0 0 0 5 10 T (deg F) 73.6 80.5 82 82.9 83.7 84.3 85.1 85.9 86.8 87.3 88 89.1 89.5 Fx Fy Fz Mx My Mz (lbs) 0.010781 6.988701 6.749577 6.619873 6.576237 6.548442 6.693852 6.831214 7.127326 9.212098 12.11298 6.672617 6.916518 (lbs) -0.012032 -0.431059 -0.489058 -0.614657 -0.52314 -0.525255 -0.682469 -0.563192 -0.433677 -0.537551 -0.460777 -3.585717 -8.235045 (lbs) -0.028225 -2.929299 0.740092 4.537245 7.86108 12.07634 16.03649 18.78229 20.88168 16.95631 14.82893 8.375125 8.65658 (lbs-in) 0.600087 1.959986 2.579629 2.285295 1.453093 0.307181 0.522041 0.586327 2.351817 -7.763657 -16.60592 -34.65988 -72.47628 (lbs-in) -0.092476 -59.72863 -55.24239 -51.33245 -48.05553 -44.18394 -41.02078 -38.16047 -35.56841 -39.2055 -40.25858 -41.54384 -39.36234 (lbs-in) -0.289459 -2.805113 -2.725257 -1.759101 -2.615784 -2.747644 -2.055718 -3.400231 -4.553399 0.051615 -1.63751 -0.169411 -9.403744 Model off Tail off Wind on VAR UNITS a (deg) 0 0 0 b (deg) 0 5 10 T (deg F) 78.1 80.1 82.5 Fx Fy Fz Mx My Mz (lbs) (lbs) (lbs) (lbs-in) (lbs-in) (lbs-in) 5.635527 -0.31733 1.091942 -1.04235 -51.22485 -1.646912 5.587263 -3.091032 1.1648 -44.88395 -44.69973 4.779194 5.850228 -7.145455 1.467987 -88.16304 -45.84466 -2.486216 Model off Tail off Wind off VAR UNITS a (deg) -6 -4 -2 0 2 4 6 8 10 15 0 0 b (deg) 0 0 0 0 0 0 0 0 0 0 5 10 T (deg F) 72.3 72.3 72.3 72.3 72.3 72.3 72.3 72.3 72.3 72.3 72.3 72.3 Fx Fy Fz Mx My Mz (lbs) 0.028441 0.043177 0.05192 0.036337 0.031385 0.02045 0.00682 0.017846 0.024835 -0.03553 0.00777 0.040518 (lbs) -0.012549 -0.010251 -0.034881 -0.011717 -0.008431 -0.001672 -0.015034 -0.044704 -0.01952 0.003813 -0.082482 -0.11664 (lbs) -0.059705 -0.064655 -0.082625 -0.029994 0.020906 -0.067541 -0.077728 -0.099026 -0.055599 0.043188 -0.043057 -0.060447 (lbs-in) 0.082251 0.631329 0.719338 0.438986 -0.061458 0.286625 0.64602 -0.260985 0.161507 0.4527 -16.26275 -32.34356 (lbs-in) -0.360937 0.508962 0.114283 1.155168 1.028247 1.344672 1.433802 1.684247 1.166787 2.650371 5.272538 8.832101 (lbs-in) -0.511322 -0.265324 -0.142598 -0.159895 -0.24703 -0.279926 0.062034 0.26886 0.189853 0.025815 1.191334 1.441786 9 American Institute of Aeronautics and Astronautics Tamb Pamb 74 29.67 Tamb Pamb 76.5 29.73 Tamb Pamb 74 29.74 Tamb Pamb 74.3 29.73 Tamb Pamb 74 29.67 Appendix C: MATLAB Code Cd_tailon Cl_tailon Cm_tailon Cn_tailon Cd_tailoff Cl_tailoff Cm_tailoff Cn_tailoff = = = = xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AF22:AF33'); xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AH22:AH33'); xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AJ22:AJ33'); xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AK22:AK33'); = = = = xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AF41:AF52'); xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AH41:AH52'); xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AJ41:AJ52'); xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AK41:AK52'); figure (1) x= xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'E20:E29'); y= xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AH22:AH31'); y1= xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AH41:AH50'); plot(x,y) hold on plot(x,y1) title('Cl v {\alpha}') xlabel('{\alpha}') ylabel('Cl') legend("tail on", "tail off") legend('Location',"best") grid on hold off figure (2) x= xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'E20:E29'); y= xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AJ22:AJ31'); y1= xlsread("LIU_AE303_Lab-5-Data.xlsx","Sheet1",'AJ41:AJ50'); plot(x,y) hold on plot(x,y1) title('Cm v {\alpha}') xlabel('{\alpha}') ylabel('Cm') legend("tail on", "tail off") legend('Location',"best") 10 American Institute of Aeronautics and Astronautics grid on hold off figure (3) beta= Cm_tailoff([4 11 12]); y= Cn_tailon([4 11 12]); y1= Cn_tailoff([4 11 12]); plot(beta,y) hold on plot(beta,y1) title('Cm v {\beta}') xlabel('{\beta}') ylabel('Cm') legend("tail on", "tail off") legend('Location',"best") grid on hold off figure (4) Cdoff= Cd_tailoff([1:10]); y1= Cl_tailoff([1:10]); Cdon= Cd_tailon([1:10]); y= Cl_tailon([1:10]); plot(Cdoff,y1) hold on plot(Cdon,y) title('C_l v C_d') xlabel('C_d') ylabel('C_l') legend("tail on", "tail off") legend('Location',"best") grid on hold off %7 Cl_Cd_Max_tailon = .932124/.0752701 Cl_Cd_Max_tailoff = .821622/.0625553 %8 y = Cl_tailon([1:10]); x = transpose([-6 -4 -2 0 2 4 6 8 10 15]); 11 American Institute of Aeronautics and Astronautics dCl_dalfaon= x\y y1 = Cl_tailoff([1:10]); x1 = transpose([-6 -4 -2 0 2 4 6 8 10 15]); dCl_dalfaoff= x1\y1 %10 dCm/dalfa y2 = Cm_tailon([1:10]); x2 = transpose([-6 -4 -2 0 2 4 6 8 10 15]); dCm_dalfaon= x2\y2 y3 = Cm_tailoff([1:10]); x3 = transpose([-6 -4 -2 0 2 4 6 8 10 15]); dCm_dalfaoff= x3\y3 %11 dCn/dBeta y4 = Cn_tailon([4 11 12]); x4 = transpose([0 5 10]); dCm_dbetaon= x4\y4 y5 = Cn_tailoff([4 11 12]); x5 = transpose([0 5 10]); dCm_dbetaoff= x5\y5 12 American Institute of Aeronautics and Astronautics