P7.101 Icebergs can be driven at substantial speeds by the wind. Let the iceberg be idealized as a large, flat cylinder, D >> L, with one-eighth of its bulk exposed, as in Fig. P7.101. Let the seawater be at rest. If the upper and lower drag forces depend upon relative velocities between the berg and the fluid, derive an approximate expression for the steady iceberg speed V when driven by wind velocity U.

The drag of an airfoil (Fig.) increases considerably ifyou turn the sharp edge around 180° to face the stream. Canyou explain this?

A ship is 125 m long and has a wetted area of 3500 m2.Its propellers can deliver a maximum power of 1.1 MWto seawater at 20°C. If all drag is due to friction, estimatethe maximum ship speed, in kn.

The large block shown is x = 72 cm wide, y = 54 cm long, and z = 9.0 cm high. This block is passing through air (density of air p = 1.43 kg/m³) at a speed of v = 8.61 m/s. Find the drag force F41 acting on the block when it has the velocity vj and a drag coefficient I = 0.812. V2 Fa.1 N %3D Find the drag force F42 acting on the block when it has the velocity vz with a drag coefficient I = 0.893. F42 N Find the drag force Fa.3 acting on the block when it has the velocity vz with a drag coefficient I = 1.06. F4.3 = N EN

P6.31 (a) A luxury sports car has a frontal area of 2.08 m? and a 0.29 coefficient of drag at 95 km/h. What is the drag force on the vehicle at this speed? (b) A sport-utility vehicle has Cp = 0.45 at 95 km/h and a slightly larger frontal area of 2.70 m?. What is the drag force in this case?

Aerodynamics NACA 747A415, chord is 180 cm 1) What is the location of favorable pressure gradient of the upper surface, measured from LE? 2) What is the location favorable pressure gradient of the upper surface, measured from TE?

An aluminum cylinder weighing 30 N, 6 cm in diameterand 40 cm long, is falling concentrically through a longvertical sleeve of diameter 6.04 cm. The clearance is fi lledwith SAE 50 oil at 20 ° C. Estimate the terminal (zeroacceleration) fall velocity. Neglect air drag and assume alinear velocity distribution in the oil. Hint: You are givendiameters, not radii.

P7.121 In gliding (unpowered) flight, lift and drag are in equilibrium with the weight. Show, that, with no wind, the craft sinks at an angle tan≈ drag/lift. For a sailplane with m = 200 kg, wing area = 12 m², AR = 12, with an NACA 0009 airfoil, estimate (a) stall speed, (b) minimum gliding angle; (c) the maximum distance it can glide in still air at z = 1200 m. Weight Drag Horizontal

Baseball drag data from the University of Texas are shownin Fig.  A baseball weighs approximately 5.12ounces and has a diameter of 2.91 in. Hall-of-Famer NolanRyan, in a 1974 game, threw the fastest pitch ever recorded:108.1 mi/h. If it is 60 ft from Nolan’s hand to the catcher’smitt, estimate the sea-level ball velocity which the catcherexperiences for (a) a normal baseball, and (b) a perfectlysmooth baseball.

The so-called Rocket Man, Yves Rossy, fl ew across the Alps in2008, wearing a rocket-propelled wing-suit with the followingdata: thrust = 200 lbf, altitude = 8,200 ft, and wingspan = 8 ft(http://en.wikipedia.org/wiki/Yves_Rossy). Further assume awing area of 12 ft2, total weight of 280 lbf, CDq = 0.08 for thewing, and a drag area of 1.7 ft2 for Rocket Man. Estimate themaximum velocity possible for this condition, in mi/h.