Required information Problem 11.110 Stokes law During an experiment, three aluminum balls (ps = 2700 kg/m³) having diameters 2, 4, and 10 mm, respectively, are dropped into a tank filled with glycerin at 22°C (pf=1274 kg/m³ and μ= 1 kg/m-s). The terminal settling velocities of the balls are measured to be 3.3, 12.7, and 60.3 mm/s, respectively. Compare these values with the velocities predicted by Stokes law for drag force FD= 3πµDV+(9π/16)pV2D2, which is valid for very low Reynolds numbers (Re << 1). Problem 11.110.b Stokes law Determine the error involved and assess the accuracy of Stokes law when the aluminum ball of 4 mm and terminal velocity of 12.7 mm/s is dropped into the tank filled with glycerin. The value of V determined by Stokes law is 12.13 mm/s. The error involved is %.

Required information Problem 11.110 Stokes law During an experiment, three aluminum balls (ps = 2700 kg/m³) having diameters 2, 4, and 10 mm, respectively, are dropped into a tank filled with glycerin at 22°C (pf=1274 kg/m³ and μ= 1 kg/m-s). The terminal settling velocities of the balls are measured to be 3.3, 12.7, and 60.3 mm/s, respectively. Compare these values with the velocities predicted by Stokes law for drag force FD= 3πµDV+(9π/16)pV2D2, which is valid for very low Reynolds numbers (Re << 1). Problem 11.110.b Stokes law Determine the error involved and assess the accuracy of Stokes law when the aluminum ball of 4 mm and terminal velocity of 12.7 mm/s is dropped into the tank filled with glycerin. The value of V determined by Stokes law is 12.13 mm/s. The error involved is %.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.55P

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