Drag coefficients for various shapes. Where: Cd is the drag coefficient.

Drag coefficients for various shapes. Theory For a given shape (geometry) the drag force is given as: Fd C d 1 2 v A 2 where: Fd is the drag force Cd is the drag coefficient ρ is the mass density of the fluid (for air: 1,219 kg/m3) v is the speed of the object relative to the fluid A is the projection area (perpendicular area to the flow) is the kinetic energy per unit volume For Jun 1, 2022 · The drag coefficient calculated using the correlation in Eq. The drag coefficient is a way to normalize the drag force for different conditions and compare the Sep 28, 2022 · The total drag is a function of both the shape of the airfoil (profile drag) and the square of the lift coefficient (lift-induced drag) which gives rise to the exponential drag rise as one approaches high angles of attack. Tip speed ratio V. Hence, it is significant to investigate shape Feb 16, 2023 · The mechanism of droplet deformation in non-Newtonian fluids were elucidated, the influence of different rheological properties on droplet shape was discussed, and the empirical correlations of droplet aspect ratio were summarized. It is calculated by dividing the drag (D) by the quantity, which is Title:SUMMARY OF DRAG COEFFICIENTS OF VARIOUS SHAPED CYLINDERS. For more information, please see document availability Jun 29, 2022 · Because their effects have been an interesting phenomenon in fluid mechanics, researchers have proposed drag, lift, and torque formulations considering the particle shape and orientation, non-Newtonian fluid effects, and heat transfer. 93). Then, recalculate distance traveled using a new delta time that is 1/2 of the original value, or twice as many iterations as the first calculation. 5 mm rising in Newtonian fluids are discussed, where the drops Reynolds numbers are from 0. Here are a few examples of drag coefficient formulas for different shapes: Sphere (Reynolds Number < 0. 2 Drag coefficient. 4. We see that as the Reynolds number increases the variation in the drag coefficient (based on cross-sectional area) decreases, and over a large range in Reynolds number it is nearly constant. Parachute drag coefficients as a function of Frames described in table I. 3 x 104 to 2. However, non-sphere particles are more common in practice. Using computational fluid dynamics (CFD) tools, the behaviour of the boundary layer at high Re has been determined by applying the Reynolds Averaged Navier-Stokes turbulence model (RANS). OSTI ID: 4373890. Sep 11, 2023 · The drag coefficient and the drag equation can then be used to determine the drag on a similar shaped object at different flow conditions as long as several flow similarity parameters are matched. 5–6. Mach numberReynolds number drag, induced drag CdiClpiARe. SUMMARY OF DRAG COEFFICIENTS OF VARIOUS SHAPED CYLINDERS. 17. The drag coefficient of a sphere depends on its size and Reynolds number. The drag coefficient (Cd) is equal to the drag (D) divided by the quantity: density (r) times reference area (A) times one half of the velocity (V) squared. A comparison between the power coefficient cp and tip speed ratio λ are shown in Fig. Because flow behavior is summarized in both regimes, the relationship between the drag coefficient vs. Download : Download high-res image (247KB) Download : Download full-size image; Fig. 23. It is the purpose of this report to present drag coefficients over a fairly wide range of Reynolds numbers (R = 104 to 2 x 10s) for a variety of cross sections. 5 x 105). According to various reports, the Mercedes-Benz A-Class saloon is perhaps the most aerodynamic car available. 4, and the drag coefficient varies less for larger Figure 8 shows drag coefficients of geometric shapes. G8 – G8s are flatbase with a 10 caliber secant ogive. First, the drag forces acting on different body-combinations in fully wetted conditions are measured. 5 degree boat-tails, with 10 caliber tangent ogive, and are very popular with manufacturers for extremely low-drag bullets. The numerical results have been validated by comparing the predicated numerical results with the previous . ) This equation can also be written in a more generalized fashion as FD = bv2, where b is a constant equivalent to 0. Nov 18, 2023 · A numerical analysis of different wing geometries was conducted, and the three winglet shapes studied here had the three best performance coefficients. 90 reported in reference 3 as being applicable for fully inflated flat parachutes. G7 – Bullets with the G7 BC are long 7. At higher Reynolds numbers the drag coefficients of the two thin elliptic cylinders (25% and 12. This rapid rise in drag coefficient is due to compressibility effects at the higher velocities. where C C is the drag coefficient, A A is the area of the object facing the fluid, and ρ ρ is the density of the fluid. 1 lists the drag coefficient for some simple shapes, (each of these objects has a Reynolds number of order 104 ). Engineering, Physics. 002 to 1,000. 25 and 0. Comparison of the values of the drag coefficients for a circular cylinder, as shown by the dotted line and test points in Figure 1, indicates sizable differences for subcritical Reynolds num- bers (Re = 1. In all cases, the reference area is the cross section orthogonal to the flow direction. Re is the Reynolds number, calculated as Re = (ρ * V * D) / μ, where: ρ is the fluid density. You should see the results converge to one Jul 28, 2022 · If we choose the wing area, rather than the cross-sectional area, the computed coefficient will have a different value. (2019) improved the drag performance of a variant of torpedo The normalized male and female body shapes were simulated at different velocities, and it was demonstrated that the male body shape has a lower drag coefficient than the female body shape by 10. Report presenting an investigation to find the approximate variation of the drag coefficient with Reynolds number of several cylinders with different cross-sectional shapes. When the fluid is a gas like air, it is called aerodynamic drag or air resistance. Aerodynamicists use a number to model all of the complex items that affect drag, including: the shape of an object, the size of an object, and the angle at which the object meets the air. The Drag Coefficient. These graphs show test results for several different Reynolds Feb 1, 2023 · The shape, rise velocity and drag coefficient of a single drop with a diameter from 1. The values shown here were determined experimentally by placing models in a wind tunnel and measuring the amount of drag, the tunnel conditions of velocity and density, and the reference area of the model. 1 [3]. Bilinear interpolations are used to estimate drag coefficients between tabulated values. SUBJECT TERMS drag coefficient, sphere, fluid, atmosphere, Mach, Reynolds 16. With the increasing through a wind tunnel to find the drag of each nose cone. 5% chord) are seen to increase suddenly, whereas the other cylinders show decreasing drag coefficients. When the movement of the body in the fluid is fast, it assumes the definition of “ turbulent ” in that many small May 17, 2007 · of expressing drag is by using drag coefficients. The bodies are assumed to be smooth (no surafece roughness) with flow from left to right. 17 Mar 1, 2019 · The purpose of this work was to predict the drag coefficients of combustion residues or rather clinker flakes with various sizes and shapes, which usually occur in industrial applications. 09 and we have road cars today that don't look like completely amorphous blobs that manage to get the drag coefficient down to numbers like 0. obvious that the experiment data of sphe re coincide well to the wel l-known standard Jan 5, 2004 · Measurements of the drag coefficients are reported in this paper for six different geometrical shapes, including isometric, axisymmetric, orthotropic, plane and elongated conglomerates of spheres. 06, due to which and as the air flows around it, it remains attached. The motion of a body in a fluid, when it is quite slow, is “ laminar “: the fluid moves, that is, as if it were made up of many thin sheets that are able to slide over each other. Pressure distribution, lift and drag coefficients are obtained for the different angle of attacks. The results show that the drag coefficients strongly depend on the body shapes. The drag coefficient of a vehicle is affected by the shape of body of the vehicle. Figure 4. . 4. In the report, the aerodynamicist must specify the area plentiful. In HEC-RAS, standard step method is most often used for the computation of water surface profiles at any Air Flow Drag, Drag Coefficient Equation and Calculators for various shapes and bodies. 75 and 9–12) of drag coefficient. 9 to 10. The drag coefficient is a number that engineers use to model all of the complex dependencies of shape and flow conditions on rocket drag. The friction component is associated to the boundary layer development, its magnitude depends on the characteristics of the fluid (i. Measured drag coefficients of some simple two-dimensional bluff bodies. It has a drag force rating of 0. drag of the various shapes (ellipses, rectangles, diamonds, and triangles) with corner radius ratio and fineness ratio. 3. Multiphase flow are involved in many fields in natural phenomenon as well as industrial applications. Moreover, the dimensionless correlations of drag coefficient were discussed. power coefficient for different wind turbines Jun 15, 2019 · Various shape parameters were introduced in the statistical development of empirical correlations valid for the drag coefficient of spherical, artificial and real irregular particles. 20. overall effects of shape, inclination, and other flow conditions. Values for some common bluff-body shapes are shown in the tables below. 8. Each nose cone was put in a body tube that was held by a black tube holder. The number scientists use is called the drag coefficient (Cd). Drag forces tend to decrease fluid velocity Nov 13, 2023 · For spherical particles, there is a well-defined correlation between the drag coefficient c d and Reynolds number Re [12,13,14,15]. , viscosity), and the Reynolds number; hence, a body immersed in a nonviscous fluid experiences no drag because it has Basically, unsharpened and bulky objects will have a high drag coefficient, and streamlined objects will have a lower drag coefficient. In practice, drag coefficients are reported based on a wide variety of object areas. However, for bodies with cross-sectional shapes other than circular, drag data are meager (e. Sep 1, 2021 · The most recent and detailed overview of the existing empirical models for the drag coefficients of irregular particles of various shapes can be found in Roostaee and Vaezi (2022). Jul 20, 2022 · The coefficient \(C_{D}\) is called the drag coefficient, a dimensionless number that is a property of the object. Fluids are characterized by their ability to flow. 168). GL – GL projectiles are blunt lead nose. Where: Cd is the drag coefficient. 35–0. [1], and Isaacs and Thodos [18], among others May 31, 2020 · The sum of pressure drag force F p and friction drag force F f finally gives the overall profile drag force F d: Fp +Ff =Fd (22) (22) F p + F f = F d. 3-3 shows the drag coefficients as a function of the Reynolds number and as a function of the Corey shape factor. Mechanics. In particular, Mach number similarity insures that the compressibility effects are correctly modeled, and Reynolds number similarity insures that the Table 1 below shows some typical drag coefficient values that can be adopted for piers. A drag coefficient calculated using the projected area of a sphere has been reported by Coulson and Richardson [24], Clift et al. The resistance (drag) coefficient Cx is a function of the Reynolds number, i. The tangent nose cone is a commonly used design used in. (Recall that density is mass per unit volume. Low-speed drag of cylinders of various shapes. [8] used the fact that the drag coefficient is a There are many equations in the literature relating the drag function of particle shape alone in the Newton regime of settling. Sorensen. 1) where C is the drag coefficient, A is the area of the object facing the fluid, and ρ is the density of the fluid. Drag coefficients of several simple 3D and 2D shapes. The velocity may be that of the object through the air (or any other gas) or the air velocity past a stationary object. In order to compare values of Cx for spherical and irregular particles, we introduce the sphericity factor k to account for the particle shape (see p. Since ages, aerodynamic drag and heating in re-entering, planetary landing and launching has been a Dec 1, 2017 · This paper presents a study of the terminal fall velocity and drag coefficient of natural particles of highly irregular shapes in a wide range of Reynolds number (0. The above model for air drag does not extend to all fluids. In the report, the test engineer must specify the area The experimental results of drag coefficients of 5 shapes of rigid particles are shown in figure 2, it is obvious that the experiment data of sphere coincide well to the well-known standard curve Jul 23, 2018 · Essentially, a longer body has a lower drag coefficient because it creates a smaller frontal area of separated flow. Heddleson, C F; Brown, D L; Cliffe, R T. The section was affected by different lift and drag coefficients, and the flow field also changed differently. A rod with a hemispherical cross section will even have a drag coefficient of 2. The drag. Feb 15, 2024 · The nature and behaviour of the drag coefficient of irregularly shaped grains within a wide range of Reynolds numbers is discussed. 10 in your textbook A is the frontal area of the submerged object C D is the drag coefficient determined from Table 1 V is the free-stream velocity measured during the lab Table 1: Known drag coefficients for various shapes Body Status Shape C D Drag (physics) In fluid dynamics, drag, sometimes referred to as fluid resistance, is a force acting opposite to the relative motion of any object, moving with respect to a surrounding fluid. Dec 1, 2023 · This ranks it among the most aerodynamic cars on the list. If this equation is divided by the term ½⋅ϱ⋅v ∞2 ⋅A, the sum of the pressure drag coefficient and the friction drag coefficient is calculated on the left side. Results obtained through the VWT simulations after mesh convergence tests were compared to the available wind tunnel The shape factor and drag coefficient. Noel K. FD = 1 2CρAv2, F D = 1 2 Cρ Av 2, 5. These materials mainly consist of irregularly-shaped particles, whereby their sizes and shapes mainly affect the drag coefficients. 7. 14. 15. Published 1 November 1953. Then, a function linking Jun 1, 2011 · [20] Still, there exists a wide variety of different empirical correlations to calculate the drag coefficients for free rising or sinking particles, especially for spheres. A plot of the quarter chord moment coefficient against angle of attack (shown below) shows how the airfoil responds to an Mar 4, 2023 · The rocket nose-cone shapes have been generated by blending few conic sections together (two conic sections in one) and the simulated against mach number regime from subsonic through transonic to supersonic. We got the results at the end of the testing. The results showed that the Long Elliptical Shape was the best nose cone. It explains in detail through particle image velocimetry measurements. Drag coefficients, C D, for several bluff and streamline shapes are shown as a function of Reynolds number. %/so. How does the drag coefficient vary for different complex shapes? The drag coefficient Rather, it relies on user-supplied tables that relate drag coefficients to Mach and Reynolds numbers. coefficient to the Reynolds number for particles of spherical The authors proposed that the effects of Re number and the shape falling at their terminal May 31, 2015 · The second approach consists in obtaining a drag coefficient expression for a fixed shape and any orientations. Cd = D / (A * . coefficient is a dimensionless number used to represent the. pressure drag. Oct 6, 2023 · The lift and drag forces at 0˚, 4˚, 8˚, 12˚, 16˚, and 20˚ angles of attack were determined and the lift coefficient, drag coefficient and lift to drag ratio were analyzed. Data is mainly obtained from White where the drag coefficients are based on experimental data, but other sources are also used [2, 3]. 9 or A. Feb 15, 2022 · The drag coefficient of a parachute is crucial in understanding its performance during descent. (See Figure 5. 1): Cd = 24 / Re. Examples of shapes I am interested in are: flat plate, cylinder, half-cylinder, rod with various sections (e. Typically, several different drag coefficients are reported. 5 * r * V^2) (wind tunnel) drag equation reference area velocity, density (altitude), air viscosity and compressibility. 5. hobby rocketry. 3-3. Lift coefficient (Cl) is a measure of the force that keeps a ball airborne and determines its ability to rise or drop during flight, while drag coefficient (Cd) measures the force that opposes the ball’s motion through the air. From these measurements, a new and accurate empirical correlation for the drag coefficient, CD, of variously shaped particles has been developed. square, triangle). The dependence of the mesh size and the grid resolution in the modelling are The drag coefficient C_D is defined by C_D = {F_D\over{{1\over 2}}\rho U^2L^2}, where F_D is the drag force, \rho is the density, U is the speed, and L is the size scale of the body (Tritton 1988, p. The drag coefficients of geometrically complex objects are usually determined by experiments in wind tunnels or water channels. When a small vent was cut into one of the parachutes for a few tests, as described earlier, no effect on drag coefficient resulted. When flowing around the forward edge of the cylinder, the flow will separate and follow a curved path that is dictated by the pressure difference between outer flow and the separated region right after the forward edge. 12. Then, a function linking Oct 8, 2019 · Tangent, parabolic, ellipsoidal and conic. 1 to 0. Athletes as well as car designers seek to reduce the drag force to lower their race times. The drag A typical presentation of drag coefficient of a circular cylinder is shown in Figure 1. 22 Cd along with a compact-sized frontal area of 2. 3). The drag coefficient (non-dimensional drag) is equal to the drag force divided by the product of velocity pressure and frontal area. Two sample user-input tables, both relating to spheres, are provided. This equation is simply a rearrangement of the drag equation where we solve for the drag coefficient in terms of the other variables. , Cx = / (Re). The shape, texture, and spin of a ball significantly influence its lift and drag coefficients. e. See table below for drag coefficients for different shapes in both 2D and 3D. When the fluid is a liquid like water it is called hydrodynamic drag, but never "water resistance". Wu & Wang (2006) recently gave an overview of drag coefficients and terminal settling velocities for different particle Corey shape factors. Jul 28, 2022 · The drag coefficient is a number that aerodynamicists use to model all of the complex dependencies of shape, inclination, and flow conditions on aircraft drag. Note that for the symmetrical shape the lift coefficient is zero at zero angle of attack. to 0. Hell I remember reading that the new A4 sedan has a drag coefficient of 0. Delany, N. The drag coefficient for this shape is given as 1. Jun 1, 2019 · In the present study, the Savonius turbine was studied which is a drag type vertical axis turbine. Examination of these data indicate that Mar 1, 2019 · In a vast number of industrial applications, particle-laden flows consist of irregularly-shaped particles with various sizes and shapes and thus, the drag coefficient is strongly affected and Aug 8, 2016 · Start with a moderately long delta time for your iterations and calculate distance traveled. Then air was sucked through the tunnel and the computer measured the drag force. drag equation CdDrVA. Two curves are shown for the ellipse with. density and viscosity), the velocity of the fluid, and the orientation of the object with respect to the flow. Non-sphere particles are usually simplified to sphere particles in multiphase flow simulation. OSTI does not have a digital full text copy available. Overviews are given by Jul 30, 2021 · The drag force exerted on ice ridges obeys a quadratic drag law (Arya, 1973), associated with wind and current velocity and the local form drag coefficients of individual obstacles, denoted by C dw for a keel and C da for a sail, where the subscripts w and a represent the ice-ocean and air-ice interface, respectively. Drag coefficient is due to friction, pressure, and induced drag. V is the velocity of the object relative to the fluid. Table 8. Jun 5, 2015 · The drag coefficient for a complex shape is affected by various factors such as the shape and geometry of the object, the fluid properties (e. How to Calculate Drag Coefficient of a Sphere. The result of their research is reflected in Figure 4. 7,9–24 Leith 10 derived the shape factor, which is the drag force modification factor for a non-spherical Jan 17, 2024 · 2. May 13, 2019 · Experiments are conducted in a cavitation tunnel of the Chungnam National University. Its shap e is formed by a segmen t of a circle, such that the rocket body is It depends on the air density, the vehicle speed, the frontal area, and the shape of the vehicle. The table on the left compares three-dimensional shapes like disks, cones, and spheres while the table on the right is for two-dimensional shapes like plates, wedges, and cylinders. Wind tunnel tests or computational simulations are used to calculate the drag coefficient for different parachute designs. To understand this, you can visualise an object of a teardrop shape; the object will have a low value of C d , approximately 0. 0 International Equation 1: Drag force equation using total profile where ρ is density determined from Table A. The measured drag coefficient for the circular cylinder in the sub- The relationship between the drag force and an object’s motion is summarized in terms of a drag coefficient, while the flow regime is summarized in terms of the Reynolds number. The Feb 27, 2023 · The fitting line of the drag coefficient is shown as the blue line in Fig. Sep 15, 2023 · When arm 2 was in the fourth quadrant, the influence of different flow directions on the hydrodynamic characteristics on the sectional shape of the underwater manipulator was investigated. The drag coefficient Cd is equal to the drag D divided Jan 21, 2023 · Effects of Shape on Drag. The drag coefficient of various body shapes has been d Mar 25, 2015 · Visit http://ilectureonline. On the 3D side, note the flat circular disk in shape #7. Apr 9, 2008 · Drag coefficient values also change depending upon the area used in the calculation of the drag force. The drag coefficients for various bodies are summarized in the following table. The relative advantage of winglets in terms of lift-to-drag ratio improvement is that they create low-radius tip vortex cores, while the reference (traditional) wing created a large vortex area. If you restrict the competition to solid objects, still the half sphere wins with a drag coefficient of 1. -. 1% May 31, 2015 · The second approach consists in obtaining a drag coefficient expression for a fixed shape and any orientations. Continue, noting the distance traveled for each calculation. In this case, determining the drag coefficient and the effects of the Reynolds number may require specific measurements in the wind tunnel to establish the drag coefficients. Data were obtained for circular cylinders Nov 22, 2023 · If we choose the wing area, rather than the cross-sectional area, the computed coefficient will have a different value. Table I presents values of the drag coefficient at Reynolds numbers of 105 (except where the lowest test Reynolds number was about 2 X 105 ) for the various shapes tested. By equating the various shape parameters to one in these general correlations indirect empirical correlations for the drag coefficient of spheres are obtained. Nov 21, 2023 · Drag Coefficient. But the drag is the same, and the coefficients are related by the ratio of the areas. g. Hartman et al. Mercedes-Benz A-Class Saloon. 15. 01–3700). At higher Reynolds niunbers the drag coefficients of the two thin elliptic cylinders (25% and 12. The average modern automobile achieves a drag coefficient of between 0. shape, inclination, some flow conditions. Apr 11, 2017 · The experimental results of drag coeffic ients of 5 shapes of rigid particles are shown in figure 2, it is. 1. Figures - available via license: Creative Commons Attribution 4. For the flat plate normal to the flow, C D is independent of Reynolds number over the range shown because flow separation occurs at the sharp corners of the The variation of the drag coefficient with Reynolds number is shown in figure 2, and the corresponding flow patterns are shown in figure 3. 19m 2. For particles of various shapes with diameters from 1 to 100 fxm in water, with Reynolds Nov 27, 2019 · So, I am wondering if anyone is aware of a good resource that contains charts of Drag Coefficient vs Reynolds number for a variety of shapes. Sport utility vehicles (SUVs), with their typically boxy shapes, typically achieve a Cd =0. Aug 20, 2015 · Its drag coefficient is 1. , see ref. However, since the drag coefficient generally depends on both Re and particle shape, the behavior of specific non-spherical particles represents a widely researched topic in numerous scientific fields [16,17,18]. 0° and 90° (C D, α = 0 °, C D, α = 90 °), from the best experimental results or from existing correlations. Table 2 shows the drag coefficient of various shapes performed in this study. Drag coefficient is an important parameter in the modelling and simulation of multiphase flow. [1] This can exist between two fluid layers, two solid surfaces, or between a fluid and solid surface. It's pretty crazy to think that a perfect "half-teardrop" has a drag coefficient of 0. May 24, 2020 · Figure: Drag coefficients of different bodies Drag coefficient of spherical bodies in laminar flows. Reynolds number is important for understanding the operating Mar 1, 2019 · The purpose of this work was to predict the drag coefficients of combustion residues or rather clinker flakes with various sizes and shapes, which usually occur in industrial applications. 42. Jun 23, 2023 · This slide shows some typical values of the drag coefficient for a variety of shapes. Rosendahl [19] suggested to determine the drag coefficient at two incidence angles (α), i. Ignacio et al. 3 (right column in the graph below). Huang (2013) analyzed the motion stability of UVs with three different cross sections of round, ellipse and rectangle. The drag coefficient is a number which aerodynamicists use to model all of the complex dependencies of drag on shape, inclination, and some flow conditions. The aerodynamic drag coefficients have been recoded for each shape for each mach number. Technical Report · Mon Apr 01 00:00:00 EST 1957. (9) is represented by the solid black line. 3. For relatively simple geometric shapes such as smooth spheres, however, scientists have tried to calculate the drag Sep 12, 2022 · FD = 1 2CρAv2, (6. 15, the fitted drag coefficients decrease from approximately 1. D is the diameter of the sphere. 5CρA. The force on an object that resists its motion through a fluid is called drag. simulation of flow field around the three different geometries was studied at different angle of attacks (-10, -5, 0, 5, 10, 15, 20, 25o). [7] To accommodate the teardrop shape of the body with a tapering end, a three-wheeled model was selected with two steerable wheels in the Sep 15, 2021 · Song (2011) studied the influence of LDR on drag of the slender hull, and obtained two optimal ranges (5. Shape Effects on Drag. Various other characteristics affect the coefficient of drag as well, and are Jan 1, 2014 · A common approach to calculate the drag acceleration experienced by a body is (1) a drag = 1 2 ρ V 2 C D S m where ρ represents the atmospheric density, V is the relative velocity of the vehicle with respect to the atmosphere, CD is the drag coefficient, S is the reference surface area and m the mass of the body. The drag force, FD = CDA (rU2/2), depends directly on this quantity. com for more math and science lectures!In this video I will explain how different shaped objects have different drag coefficients Feb 12, 2024 · Theory The drag force ( F d ) experienced by an object in a fluid flow can be calculated using the equation: =12 2 F d = 21 ρv 2 AC d where: ρ is the fluid density, v is the velocity of the object relative to the fluid, A is the reference area (projected area of the object), C d is the drag coefficient. Cdi = (Cl^2) / (pi * AR * e) Apr 9, 2008 · The terminal velocity of a particle in free settling can be calculated from the force balance on the particle through the determination of a drag coefficient as follows: U t = 2 m p g ( ρ p − ρ f) ρ f ρ p A p C D, where Ut is the terminal velocity, CD is the particle drag coefficient based on the projected area, mp is the particle mass Jul 28, 2021 · The study of drag coefficients of various body shapes is important to understand vehicle aerodynamics. 45. In the reference projectiles for each standard coefficient, the aforementioned Figure A-1 shows data for the NACA 0012 airfoil, a classic symmetrical shape that is used for everything from airplane stabilizers and canards to helicopter rotors to submarine “sails”. 7 ). rd fn vg yu hd tg sh mx nb ka