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Interactive Self-Study Module: Convective Heat Transfer over a Flat Plate

Overview:

This module uses screencasts and an interactive simulation to explain convective heat transfer over a flat plate. Your retention of material in this module will increase if you write down reasons for your answers to ConcepTests and questions to answer before using interactive simulations, and you try to solve the example problems before watching the screencast solutions. We suggest using the learning resources in the following order:

  1. Attempt to answer the multiple choice ConcepTest and solve the example problem before watching the screencasts or working with the simulations.
  2. Watch the screencasts that describe convective heating and how to solve convection problems.
  3. Review the important equations for flow over a flat plate.
  4. Use the interactive simulation to further understand laminar flow over a flat plate.
  5. Try to solve the example problems before watching the solutions in the screencasts.
  6. Answer the ConcepTests.
  7. Look at the list of key points, but only after you try to list the key points yourself.
Motivation:
  • The dynamics of heat transfer from a solid into a flowing fluid can be very complicated. It is complicated because the governing equations of fluid mechanics, such as the Navier-Stokes and continuity equations, and the governing equations of heat transfer, such as the heat diffusion equation, are now linked. You cannot describe heat transfer into a flowing fluid without understanding all of the governing equations. In this self-study module we will examine the “simplest” case: the tangential flow of a fluid over a flat, heated plate.
  • This module is primarily intended for a Heat Transfer course.
Before studying this module, you should be able to:
  • Describe the momentum boundary layer of a fluid flowing over a flat plate.
  • Work with dimensionless parameters, such as the Reynolds number.
  • Describe laminar fluid flow and turbulent fluid flow.
  • Explain the basics of the Navier-Stokes and heat diffusion equations and how to simplify them.
After studying this module, you should be able to:
  • Describe the meaning of a thermal boundary layer and sketch its thickness over a heated flat plate.
  • Name one or two fluids that have momentum boundary layers that are thicker than their thermal boundary layers.
  • Name one or two fluids that have momentum boundary layers that are thinner than their thermal boundary layers.
  • Calculate the relative thicknesses of the thermal and momentum boundary layers using the Prandtl number.
  • Use an appropriate correlation to calculate the average heat transfer coefficient over a flat plate.
  • Calculate the total heat loss from the plate (in Watts) using the average heat transfer coefficient.