Application of polymeric coatings to fibers can be accomplished by drawing a fiber through a bath of molten polymer: see schematic below. R Wire 2kR Molten Polymer →V Let's assume steady, isothermal, and incompressible flow. i. Using Navier-Stokes equations in a cylindrical coordinate system along with appropriate boundary conditions, derive an expression for the z velocity as a function of the radial coordinate r. ii. Show that the amount of polymer coated per unit time, say M, is given by M =p¹Vk²(1-2Ink)-1] where p denotes the density of the molten (liquid) polymer. iii. In good engineering design it is important to be able to control the product parameters (coating thickness in the present case) by varying process variables (draw speed). From this point of view, can the proposed design be improved? If so, how?

Application of polymeric coatings to fibers can be accomplished by drawing a fiber through a bath of molten polymer: see schematic below. R Wire 2kR Molten Polymer →V Let's assume steady, isothermal, and incompressible flow. i. Using Navier-Stokes equations in a cylindrical coordinate system along with appropriate boundary conditions, derive an expression for the z velocity as a function of the radial coordinate r. ii. Show that the amount of polymer coated per unit time, say M, is given by M =p¹Vk²(1-2Ink)-1] where p denotes the density of the molten (liquid) polymer. iii. In good engineering design it is important to be able to control the product parameters (coating thickness in the present case) by varying process variables (draw speed). From this point of view, can the proposed design be improved? If so, how?

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 5.3P: Evaluate the Nusselt number for flow over a sphere for the following conditions: D=0.15m,k=0.2W/mK,...

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