WATER BOTTLE ROCKET Team 9: Darren Combs, Lauren Darling, Andrew Moorman, Esteben Rodriguez, Amanda Olguin Introduction Static Testing OVERVIEW Methods Baseline Rocket MATLAB Rocket Design Sensitivity Adjustments Modified Rocket Predictions Results Lessons Conclusions Team 9 2 INTRODUCTION model

manufacture Goal Fly analyze Proces s Team 9 Apply previous aerodynamic and thermodynamic knowledge to build a bottle rocket trajectory code 3 OVERALL CONCEPTS 3 (4) Phases of flight Depends on model used

Drag, thrust and weight The rocket fins will align themselves parallel to free stream Assumption: rocket will point into the wind Team 9 4 GOVERNING EQUATIONS =0 = = 2 +( ) Phase 3 Phase 2 +( ) = Phase 1 Team 9

5 STATIC TESTING Allows measurement of the total force that is exerted throughout firing Load Cells push against a stationary structure with a load cable attached that measure force Long string of data is cut down and then adjusted in order to correctly approximate Isp ) Team 9 6 WIND TUNNEL The wind tunnel allows us to come up with a coefficient of drag for our rocket. Spinning vs. non-spinning rocket: making a rocket spin provides stability.

1 2 = 2 Solve for Cd =2 Team 9 2 7 BASELINE ROCKET 4 fins triangular in shape 3.25 inch base by 3 inch height Set parallel to the airflow close to the nozzle Payload consist of an altimeter and packing

peanuts (27 grams) Weight of rocket: 160 grams Payload hub is at the nose of the rocket encapsulated by extra casing (bottom of a 2 liter bottle) Payload nose of rocket included holes for accurate pressure readings Team 9 8 THERMO MODEL Pros: Takes into account most variables Cons: So many inputs to keep track Most are variable throughout Team 9 9 THERMODYNAMIC MATLAB MODELING Input Values

Wind conditions Wind tunnel data Initial conditions ODE 45 Results & Plots Team 9 10 ISP MODEL Pros: Easiest to model Ballistic for majority of launch Cons: Initial V gives rocket initial V gives rocket initial momentum propelling it to go further. Team 9

11 Input Values Upload Wind Tunnel Data/ Compute Drag Set Conditions Upload Static Test Data / Compute V Isp MATLAB Modeling Adjust Wind Data ODE 45 Plots/ Angle Computation

Outputs Team 9 12 INTERPOLATION MODEL Pros: Pulling real thrust values Cons: Interpolation/finding values gets tricky Data collection is very sensitive Team 9 13 Input Values Upload Wind Tunnel Data/ Compute Drag Set

Conditions Adjust Wind Data Interpolation MATLAB Modeling Upload Static Test Data / Compute Thrust ODE 45 Plots/ Angle Computation Outputs Team 9 14 SENSITIVITY ADJUSTMENTS Exit Area Drag Coefficient Water Mass Water Density

Pressure Team 9 20.7 ft increase per 1 in decrease of diameter exit 15.5 ft increase per 0.1 decrease in Cd 48.5 ft increase per 1 kg decrease in water mass 0.011 ft increase per 1 kg/m^3 decrease of water density 3.38 ft increase per 1 psi increase of pressure 15 MODIFIED ROCKET DESIGN How did you choose your design? Changing water fraction yielded the highest range change The final design became the base TA rocket with an adjusted water mass of 600 grams.

Team 9 16 UNCERTAINTIES Random Wind Wind Angle Temperature Air Density Team 9 Gaussian Water 2 grams Pressure 1 psi Cd 0.2 Thrust (Interp model) 10 lbf Launch Stand 1 degree Initial Velocity (ISP model) 10 mps Angle Finder 5 degrees Time of Flight 1 sec 17 THERMODYNAMIC FLIGHT

PREDICTION Semi major Axis: 271 ft Semi minor Axis: 127 ft Data scatter represents 100 runs Team 9 18 ISP FLIGHT PREDICTION Semi major Axis: 389 ft Semi minor Axis: 130 ft Data scatter represents 100 runs Team 9 19 INTERPOLATION FLIGHT PREDICTIONS Semi major Axis: 34.4 ft Semi minor Axis: 31.4 ft Data scatter represents 100 runs Team 9

20 RESULTS FROM LAUNCHES 4/16 Actual Isp Max Height NA 18910 728 447 Interp Thermo Altimeter 4/16 Max Height Actual NA Isp 1953 Interp

956 Thermo 641 Altimete Team 9 Distanc e 2338 3232 Deflectio n 4 Left 4.1 Right Duratio S1 S2 n 4.7 sec 31 36 5.3 sec 56.7 30.2 1997 165

6.9 Right 3.9 sec 58 Right 3.1 sec 62.9 16.8 50.9 10.5 11.2 6.8 Distanc e 2066 32310 222 157 Deflectio n 0 6.0 Right 9.9 Right 39.2Righ t S1

S2 S3 32 33.8 24.1 18.3 40 33.8 24.2 18.4 31 27.6 16.6 11.6 Duratio n 4.54 sec 5.3 sec 4.3 sec 3.6 sec

S3 28 23.7 Launch Angle: 45 Pressure: 40 PSI Water: 600g Wind speed: 5 mph from ENE Launch Angle: 45 Pressure: 40 PSI Water: 530g Wind speed: 7 mph from NNE 21 RESULTS FROM LAUNCHES 4/21 Max Distanc Deflectio Durati Heigh e n on

t Actual NA 211 0 4.24 sec Isp 1863 310 0.8 Right 5.2 sec Interp 297 744 3.5 Right 2.6 sec Thermo 778 14010 sec 4/21 Max Distanc 18.3Righ Deflectio 3.9 Duratio tn Height e n

Altimete 84 4.64 Actual NA 221 4 Left 4.83 sec rIsp 19210 3289 .3 Right sec 5.4 sec Interp 1345 2689 4.8 Right 4.9 sec Thermo 60 1628 3.3 Right 3.5 sec Altimet 8910 4.69 sec Team 9 S1

S2 S3 26.5 28 36 33.5 10.1 24 S1 33.6 10.2 24.1 S2 27 5.3 14.6 S3 35

55.4 32 29.9 23 23.7 28.8 57 28.7 15.2 21.6 9.7 Launch Angle: 45 Pressure: 40 PSI Water: 600g Wind speed: 2 mph from S Launch Angle: 45 Pressure: 40 PSI Water: 600g

Wind speed: 2 mph from NNE 22 ALTIMETER DATA Raw Data Altimeter data Validation of code comes from comparing it to the data accrued from the various launches the rocket performed. Team 9 Adjust and Zero data to flight Pressure Altitude Converter to

find height Subtract altitude of launch site to find height of launch 23 LESSONS LEARNED Parameters that likely had the greatest effect on the flight in our case was water fraction and PSI. Dont give rockets to small children as it is possible fins will be removed. Rockets that are unstable can be stabilized if fins are oriented to spin the rocket. The process of physically manufacturing and testing a model design. Team 9 24

DISCUSSION/CONCLUSIONS Greatest Uncertainty Factors: Wind, Initial momentum, Exit coefficient, integration techniques. Interpolation Model performed most accurately to our launch results Error issues come from the difficulty in modeling each factor and the configuration of air holes for the payload Future Improvements: Find scientific way to determine coefficient of friction on test stand. Soap is rather viscos. Maximize height of rocket along with distance. Team 9 25 SOURCES Wind Tunnel Rocket Test Procedure. Boulder: University of Colorado Aerospace Engineering Sciences Department, 27 Apr. 2014. PDF. Static Test USB VI Procedure. Boulder: University of Colorado Aerospace Engineering Sciences Department, 27 Apr. 2014. PDF. Static Test Firing Procedure. Boulder: University of Colorado Aerospace Engineering Sciences Department, 27 Apr. 2014. PDF. Launch Pad Procedure. Boulder: University of Colorado Aerospace Engineering Sciences Department, 27 Apr. 2014. PDF. TA Rocket Specifications. Boulder: University of Colorado Aerospace Engineering Sciences Department, 27 Apr. 2014. PDF. Rocket Lab Presentation Criteria. Boulder: University of Colorado Aerospace

Engineering Sciences Department, 27 Apr. 2014. PDF. Team 9 26