Įven further down the rabbit hole, I'd suggest looking into Gerald Taylor's work (G_T on RCGroups). He's got full construction plans up, and this is a woody RES, so there's plenty to glean from here. The concept is to change the foil along the wing to better control the lift profile and manage the lateral airflow along the foil to simultaneously improve the slipperiness (penetration and energy retention) and overall floatyness of the wing. One thing to note is the jump in sophistication - he didn't use a single airfoil, but but a progressive series of foils along the span. The sweet spot for your current design goals, I'd encourage you to look at the " Bubble Dancer" for a similar span wing. Most of his documentation is still available online, and his airfoils are still used on some fairly competitive models. A skilled airfoil designer, his wings (and entire airframes) were all the rage about 10-15 years ago. Simple to do and good return on little effort.Ī touch further down the hole, I'd point to the work of Mark Drela, out of Charles River RC. In any case, the S-3071 was a fairly popular foil in this era, the bottom is relatively flat (so a rib and sheeting method should create an accurate foil) and commonly done as constant foil from root-to-tip with the tips hand-sanded to TLAR. (my plans are to carbon-sheet it, add flaps instead of ailerons and electrify it. In either case, this airframe - the Bob Sealy Laser - is an uncommon airframe, but every reference I've seen speaks positively about it. These are both low-RE foils, with the S-3071 selected to be the more-slippery variant of that glider. As I write this, I'm looking at two sets of foam cores cut for S-3071 and S-7032 to be used in a 3m foamcore-balsa sheeted wing on a 25 year old design that lands at the edge of you're golden window. That being said, I have no direct recommendations among those sets, and few tend to perform in an optimum manner at the low Re RC gliders tend to float at.Ī step deeper, let's move to the sweet-spot of the age you're building around - just before composites came into their own. They are explicitly all over the map in regards to performance - the different digits describe parameters of the airfoil itself, with the 3 and 4 describing different geometry, and the 5 series describing lift characteristics. but there's some merit in an nice ol' scratch woody.įirst, I wouldn't be so hasty to turn your nose up at NACA's so quickly (of any series). That can be fun, and is a fairly common strategy for several decades, though most builders these days eschew pure balsa for composites if this is their goal. So 3m lead-sled (Glider optimized for energy retention in speed rather than floatyness to punch through turbulence and sink). Two distinct types of hysteresis in reattachment were observed.So. Once the flow was separated, the separation point moved upstream and the suction peak decreased in magnitude with increasing Reynolds number. The stall angle and the maximum lift coefficient increased with Reynolds number. As the Reynolds number was increased beyond this value, the stall type gradually shifted from trailing-edge stall to leading-edge stall. A fundamental change in the flow behaviour was observed around Re_c= 2.0 × 10^6. As such, attached and separated conditions, as well as the static stall and reattachment processes were studied. The angle of attack was incrementally increased and decreased over a range of 0° ≤ alpha ≤ 40°, spanning both the attached and stalled regime at all Reynolds numbers. The use of a high-pressure wind tunnel allowed for variation of the chord Reynolds number over a range of 5.0 × 10^5 ≤ Re_c ≤ 7.9 × 10^6. Reynolds number effects on the aerodynamics of the moderately thick NACA 0021 airfoil were experimentally studied by means of surface-pressure measurements. National Defense Science and Engineering Graduate Fellowship National Science Foundation grant CBET 1652583 Static measurements of a NACA 0021 airfoil at high Reynolds numbers Please use this identifier to cite or link to this item: Princeton University Undergraduate Senior Theses, 1924-2022 Princeton University Masters Theses, 2022-2023 Princeton University Doctoral Dissertations, 2011-2023 Princeton School of Public and International Affairs Liechtenstein Institute on Self-Determination Lewis-Sigler Institute for Integrative Genomics Department of Slavic Languages and Literatures
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