QUESTION 4 |(a) The Stokes number, S1, used in particle-dynamics studies is a dimensionless combinationof five variables: acceleration of gravity g, viscosity µ, density p, particle velocity U, andparticle diameter D. If St is propotional to u and inversely propotional to g, find itsdimensionless form.(b) When tested in water at 20°C flowing at 2 m s'', an 8 cm diameter sphere has a measureddrag force of 5 N. Determine the velocity and drag force on 1.5 m diameter weather balloonmoored in sea-level standard air under dynamically similar conditions?(c) The power, W, generated by a certain windmill design depends upon its diameter, D, theair density, p, the wind velocity, V, the rotation speed, 2, and the number of blades n. Byusing velocity V, diameter D and density p as the repeating variables, prove thedimensionless relationship is given byWΩpD?y³Dyn

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(a) The Stokes number, St, used in particle-dynamics studies is a dimensionless combination of five variables: acceleration of gravity g, viscosity µ, density p, particle velocity U, and particle diameter D. If St is propotional to u and inversely propotional to g, find its dimensionless form.

(a) The Stokes number, St, used in particle-dynamics studies is a dimensionless combination of five variables: acceleration of gravity g, viscosity µ, density p, particle velocity U, and particle diameter D. If St is propotional to u and inversely propotional to g, find its dimensionless form.

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.9P: When a sphere falls freely through a homogeneous fluid, it reaches a terminal velocity at which the...

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