The viscous torque T produced on a disc rotating in a liquid depends upon thecharacteristic dimension D, the rotational speed N, the density pand the dynamicviscosity u.a) Show that there are two non-dimensional parameters written as:Tand a,PND?b) In order to predict the torque on a disc of 0.5 m of diameter which rotates in oil at200 rpm, a model is made to a scale of 1/5. The model is rotated in water.Calculate the speed of rotation of the model necessary to simulate the rotation ofthe real disc.c) When the model is tested at 18.75 rpm, the torque was 0.02 N.m. Predict thetorque on the full size disc at 200 rpm.Notes: For the oil: the density is 750kg/m² and the dynamic viscosity is 0.2 N.s/m².For water: the density is 1000 kg/ m² and the dynamic viscosity is 0.001 N.s/m².kg.mIN =1

viscous torque T produced on a disc rotating in a liquid depends upon teristic dimension D, the rotational speed N, the density pand the dyna sity u. Show that there are two non-dimensional parameters written as: T and a, PND² AN²D° In order to predict the torque on a disc of 0.5 m of diameter which rotates in c 200 rpm, a model is made to a scale of 1/5. The model is rotated in w Calculate the speed of rotation of the model necessary to simulate the rotatio the real disc. Whan the 18 75 mm ua mne 00m N Pradi

viscous torque T produced on a disc rotating in a liquid depends upon teristic dimension D, the rotational speed N, the density pand the dyna sity u. Show that there are two non-dimensional parameters written as: T and a, PND² AN²D° In order to predict the torque on a disc of 0.5 m of diameter which rotates in c 200 rpm, a model is made to a scale of 1/5. The model is rotated in w Calculate the speed of rotation of the model necessary to simulate the rotatio the real disc. Whan the 18 75 mm ua mne 00m N Pradi

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 6.32P

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