Rocketproject
- 1. Rocket Nozzle Design Group Members: Mike Nick
- 2. Introduction... Presentation Outline Introduction (Nick) Brief Theory / FLUENT Modeling (Mike) Literature / Experimental Data (Nick) Conclusion (Mike)
- 3. Introduction... Project Objectives 1)To analyze four simplified nozzle geometries in a model rocket and calculate their maximum thrust. 2) Compare the theoretical and experimental thrust of these nozzles. Choose the best nozzle based on our data.
- 4. Introduction... Which simplifications? The Nozzle Configurations we modeled: 1) 2) 3) 4) Orifice Converging Nozzle Diverging Nozzle Converging-Diverging (Click on links above to see the various configurations)
- 5. Introduction... Rocket Particulars The type of rocket we modeled: 1) Solid Propellant / Core Burning Core burning rockets burn propellant from the “inside out.” This is in comparison to endburning rockets which burn propellant from the “bottom up.” Graphic from: http://www.sewanee.edu/physics/SEMINARS/HTML%20Rowland/sld011.htm
- 6. Introduction... Rocket Particulars The size of rocket we modeled: 0.25 Inch diameter casing 2) 2.25 Inches Long
- 7. Brief Theory How to calculate thrust The general thrust equation is given as follows: Graphic from: http://members.aol.com/ricnakk/th_thrst.html
- 9. GAMBIT The Mesh Triangular Elements 40 to 400 Intervals/Inch
- 10. FLUENT Assumptions 1) 2) 3) 4) Axisymmetric 2D Flow Steady State / Constant Pressure Inlet Compressible Flow Ideal Gas (air)
- 11. FLUENT Particular Settings 1) 2) 3) 4) On all configurations the iterations were run to a residual of 1e-3 Turbulent Flow (K-E model) Variable Density Used 2nd Order Equations to Calculate Density / Pressure / Momentum
- 15. FLUENT Results Nozzle Type Force (oz) Converging 4.56841 Diverging 3.81035 Regular Orifice 4.18331 Converging - Diverging 7.53282
- 16. FLUENT Graphical Results FLUENT Results Thrust (oz) 8.00 Converging 7.00 6.00 Diverging 5.00 4.00 3.00 Regular Orifice 2.00 1.00 0.00 1 Converging Diverging
- 17. Literature The preponderance of literature clearly shows the Converging – Diverging Nozzle as the most efficient nozzle design. Diagrams like this (right) are not uncommon: Graphic from: http://www.nakka-rocketry.net/lambda_p.html
- 19. Experimental Data Introduction Homemade rockets with these four various nozzle geometries were built and tested. All thrust values were measured and recorded.
- 20. Experimental Data Experimental Setup Method #1 Method #1 In this case the nozzle thrust was downward onto the scale. Before ignition, a thin metal plate was placed on top of the scale to protect it from the flame.
- 21. Experimental Data Testing Using Method #1 For record keeping, a camcorder was zoomed up close to the scale and recording. Note the metal plate protecting the plastic of the scale.
- 22. Experimental Data Method #1 (Thrust Downward) Set 1 (oz) Set 2 (oz) Converging 0.5 0.4 Diverging 0.25 dud Regular Orifice 0.6 0.7 Converging - Diverging n/a n/a Nozzle Type
- 23. Experimental Data Experimental Setup Method #2 Method #2 In this case the nozzle was placed into a hollow tube and thrust was directed upward. Thus the rocket pushed onto the scale.
- 24. Experimental Data Testing Using Method #2 Note the camcorder was zoomed up close to the scale. (Right) Movie of ConvergingDiverging Run: Click on Image to Play
- 25. Experimental Data Data Using Method #2 We were able to go back and watch our results on TV in slow motion.
- 26. Experimental Data Method #2 (Thrust Upwards) Nozzle Type Set 3 (oz) Converging 0.6 Diverging 0.45 Regular Orifice 0.25 Converging - Diverging 0.90
- 27. Conclusion FLUENT Results Thrust (oz) 8.00 Converging 7.00 6.00 Diverging 5.00 4.00 3.00 Regular Orifice 2.00 1.00 0.00 1 Converging Diverging Experimental Data Results Thrust (oz) 1 Converging 0.8 Diverging 0.6 0.4 Regular Orifice 0.2 0 1 Converging Diverging
- 28. Next time…
- 29. Questions?
- 31. Diverging
- 32. Converging
- 33. Orifice