Q3: The power output (P) of a marine current turbine is assumed to be a function of velocity U, blade length L, angular velocity w, fluid density p and kinematic viscosity v. P ´wL UL (a) Use dimensional analysis to show that, PU³L² (b) In a full-scale prototype the current velocity U = 2.0 m/s and the angular velocity is o = 15 rpm. A 1:10 scale laboratory model is to be tested in fluid of the same density with angular velocity w = 60 rpm. What velocity should be used in the model tests? (c) If the power output in the model tests is 200 W, what power output would be expected in the prototype? Answer: (a) (pu³L²) = f (,"), (b) U, = 0.8 m/s , (c) P,= 312 kW

Q3: The power output (P) of a marine current turbine is assumed to be a function of velocity U, blade length L, angular velocity w, fluid density p and kinematic viscosity v. P ´wL UL (a) Use dimensional analysis to show that, PU³L² (b) In a full-scale prototype the current velocity U = 2.0 m/s and the angular velocity is o = 15 rpm. A 1:10 scale laboratory model is to be tested in fluid of the same density with angular velocity w = 60 rpm. What velocity should be used in the model tests? (c) If the power output in the model tests is 200 W, what power output would be expected in the prototype? Answer: (a) (pu³L²) = f (,"), (b) U, = 0.8 m/s , (c) P,= 312 kW

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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