Reference / Paper · 2013
Peak of Flight #346: Drag of Nose Cones
Apogee Components' Peak of Flight newsletter, issue 346 (2013-08-27).
- peak-of-flight
- apogee-components
- model-rocketry
Reference / Paper · 2013
Apogee Components' Peak of Flight newsletter, issue 346 (2013-08-27).
Apogee Components' Peak of Flight newsletter, issue 346 (2013-08-27).
In This Issue Drag of Nose Cones Cover Photo: The Madcow Momba rocket rips into the sky with a skidmark motor. Get one for yourself at: www. ApogeeRockets.com/Rocket_Kits/High_ Power_Rockets/Momba_Rocket_Kit Apogee Components, Inc. — Your Source For Rocket Supplies That Will Take You To The “Peak-of-Flight” 3355 Fillmore Ridge Heights Colorado Springs, Colorado 80907-9024 USA www.ApogeeRockets.com e-mail: [email protected] Phone: 719-535-9335 Fax: 719-534-9050 ISSUE 346 AUGUST 27, 2013 Drag of Nose Cones By Ashley Van Milligan {Editor’s Note: In Peak-of-Flight Newsletter #345 (www. ApogeeRockets.com/Education/Downloads/Newsletter345. pdf), I wrote about how to borrow time in a research wind tunnel. In this issue, we’ll share some of the data that was collected by my daughter Ashley. She is 8 years old, and this is a snippet of her R&D project that she presented at NARAM-55 in Aurora, Ohio. The full version can be found on the Apogee web site at: www.ApogeeRockets.com/Tech/ RD_Projects_from_the_NAR} The Objectives Of The Work My project was to find the best shaped nose cone that had the lowest drag. This was done by measuring the force in a wind tunnel. The Approach Taken 1. Where did I get the idea for my research project? I got my idea from my dad’s book, 69 Simple Science Fair Protectors With Model Rockets (page 92), “Which Nose Cones Are the Best?” 2. Where did I get the nose cones? My dad made some of the nose cones. I got the rest from Apogee Components, at the Science Fair Collection (http://www.apogeerockets. com/Rocket_Kits/Skill_Level_1_Kits/Avion_Nose_Cone_ Science_Fair_Kit). 3. How did I make the nose cones? First I got the Science Fair Nose Cones. Then I lightly sanded them. Then I sealed them and sanded them to make them smooth. After that, I painted them gray and then I wet sanded them to make all of the nose cones the same smoothness. My dad helped me make the rest of them. 4. Then I went to the Air Force Academy to test them. The people there helped me with the wind tunnel and the measurements. We wrote down the data. It took 45 minutes to test all nine shapes. 5. When we got home we looked at the information. We wrote it down in our chart and my dad helped me make a graph showing how they compared. References to previous work done on the subject, found in research preparatory to this report: The references that I found show that not everyone agrees which nose cones have less drag. Above image from: Topics In Advanced Model Rocketry (page 381), by Gordon K. Mandell, George J. Caporaso, William P. Bengen (www.ApogeeRockets.com/Rocket_Books_Videos/Books/Topics_In_Advanced_Model_ Rocketry). Continued on page 3 About this Newsletter Newsletter Staff You can subscribe to receive this e-zine FREE at the Apogee Components web site (www.ApogeeRockets.com), or by sending an e-mail to: [email protected] with “SUBSCRIBE” as the subject line of the message. Page 2 ISSUE 346 Writer: Tim Van Milligan Layout / Cover Artist: Tim Van Milligan Proofreader: Michelle Mason AUGUST 27, 2013 Continued from page 2 Drag of Nose Cones The Equipment Used: The nine nose cones that I tested: #1 – Parabolic, 2” long. Plastic – Apogee Components, PNC-24A #2 – Ogive, 2” long, Balsa – Apogee Components Above image from: Estes IndusScience Fair Nose tries, “TR-11 Aerodynamic Drag of Cone Assortment Model Rockets” (page 11) by Dr. #3 – Long Gerald M. Gregorek Elliptical, 2” long, Balsa – Apogee Components Science Fair Nose Cone Assortment #4 – Short Elliptical, 1-3/8th inch long, lengthened to 2” long with a body tube. Apogee Components VFNC-24B. #5- Long Cone, 2” long, Balsa – Apogee Components Science Fair Nose Cone Assortment The short elliptical shape nose cone was lengthened by adding a straight tube to the back end. #6-Short Cone, 2” long, Balsa – Apogee Components Science Fair Nose Cone Assortment #7-Solid Cylinder, long, Balsa – Apogee Components Science Fair Nose Cone Assortment #8-Cupped Cylinder, Made from a 2” long BT-50 tube, with a tube coupler for the shoulder. The bottom of the cup is 1.5 inches from the top. It was made from a cardboard circle. #9-Vented Cupped Cylinder, Made from a 2” long BTContinued on page 4 • Won’t Shatter Like Brittle Phenolic Tubes! • Super Smooth Surface With Tight Spirals • Standard LOC Diameters Up To 6 inches • Cut and Slot With Standard Tools • No Fiberglass Wrap Needed • Sands and Paints Easily • Cheaper than Fiberglass Blue Tube From Always Ready Rocketry www.ApogeeRockets.com High Power Tubes & Couplers www.ApogeeRockets.com/Building_Supplies/Body_Tubes/Blue_Tubes ISSUE 346 AUGUST 27, 2013 Page 3 Continued from page 3 Drag of Nose Cones Katrina McGuire helped run the wind tunnel for my nose cone project. The “cupped cylinder” nose cones were made from body tubes and couplers. A paper disk above the coupler closed off the tube. 50 tube, with a tube coupler for the shoulder. The bottom of the cup is 1.5 inches from the top. It was made from a cardboard circle. Four vents were made with a paper punch above the bottom of the cup. The Facilities Used United States Air Force Academy Department of Aeronautics Laboratory: 12” Wind Tunnels Open Circuit, Eiffel type. Katrina put the nose cones into the wind tunnel. Continued on page 5 Think of the convenience of getting everything to professionally install your dual-deployment or other electronic payload into a e-bay of your rocket! Includes: nylon standoffs, screws & nuts, wire, push-switch, drill & tap, ejection charge cannisters, barrier strips, wire ties, and step-bystep DVD instructions. www.apogeerockets.com Page 4 ISSUE 346 AUGUST 27, 2013 www.ApogeeRockets.com Electronics Hardware Installation Kit Continued from page 4 Drag of Nose Cones Picture of the wind tunnel. I used a level to make sure the nose cone was level. Nose cone mounted in the wind tunnel. The big fan in the wind tunnel. Continued on page 6 • Big Kits with Classic Styling and Bold Graphics • All Rockets Feature Laser-Cut Plywood Fins and Rings NEW! • Easy-to-Build. Durable. 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ISSUE 346 AUGUST 27, 2013 www.ApogeeRockets.com • Reusable Rocket Motors Save Money Your Source For Everything Rocketry High-Power Reload Casings Page 7 Continued from page 7 Drag of Nose Cones Nose Shape Parabolic Wind Speed Temp 39.28 mph 72.0° F Drag Force 4.477 g Ogive 39.28 mph 72.0° F 4.942 g Long Eliptical 39.27 mph 72.0° F 4.149 g Short Eliptical Long Cone 39.27 mph 72.0° F 4.791 g 39.26 mph 72.5° F 4.561 g Short Cone 39.25 mph 72.0° F 5.248 g Solid Cylinder 39.24 mph 72.0° F 8.659 g 39.26 mph 72.0° F 10.459 g 39.19 mph 72.5° F 10.399 g Cupped Cylinder Vented Cupped Cylinder The Data Collected: The chart on the left shows the drag force for each nose cone we tested. This was the order they were tested in the wind tunnel. The graph on the next page shows a relative comparison of all the nose cones. They are in order of lowest drag to highest drag. The Conclusions Drawn The conclusion drawn, if you want your rocket to go high you should use the best nose cone. You should use the Long Elliptical shape, because it has the lowest drag. Don’t use the high drag shapes like the Cupped Cylinders. Putting holes in the Cupped Cylinders does not make a big difference at all because the drag does not go down. Continued on page 9 Page 8 ISSUE 346 AUGUST 27, 2013 Continued from page 8 Drag of Nose Cones Cupped Cylinder Cupped Cylinder With 4 Vent Holes Solid Cylinder 11.0 10.0 8.0 Short Cone Ogive Short Eliptical Long Cone 6.0 Parabolic 7.0 Long Eliptical Drag (grams) at 39 mph 9.0 5.0 4.0 3.0 2.0 1.0 Nose Cone Shape We’re Paying Cash For Great Articles for This Newsletter Are you a writer looking for some serious pocket change? We’re paying up to $350 for good how-to articles for this newsletter. If you’re interested, see our submission guidelines on the Apogee web site. www.ApogeeRockets.com/Newsletter/Newsletter_Guidelines ISSUE 346 AUGUST 27, 2013 Page 9