ME 259 FINAL EXAM REVIEW

Open book, notes, & homework

Text Coverage:

Chapter 9 (Natural Convection) 9.1-9.3, 9.5-9.9, 9.11

Chapter 11 (Heat Exchangers) 11.1-11.5, 11.7

Chapter 12 (Radiation) all sections

Chapter 13 (Radiation) 13.1-13.4, 13.6

Understand:

  • The physical process of natural convection and the important dimensionless parameters
  • When natural convection is important, as compared to forced convection
  • The differences between concentric tube, shell-and-tube, and crossflow heat exchangers
  • The importance of adding fins to heat exchange surfaces
  • The relative advantages of the LMTD and -NTU analysis methods for heat exchangers
  • The basic nomenclature of radiation heat transfer: emission, irradiation, radiosity, reflectivity, transmissivity, absorptivity, emissivity, Stefan-Boltzmann law, Kirchhoff's law, gray surface, black surface, diffuse surface, opaque surface, nonparticipating gas, effective sky temperature, view factor, reradiating surface, radiation shield
  • The relationship between emission, irradiation, and radiosity fluxes
  • The relationship between reflection, transmission, and absorption
  • The equivalent electrical circuit representation of multi-surface radiation enclosures
  • The difference between surface and spatial radiation resistances
  • When radiation is important compared to convection

Know How To*:

  • Apply empirical convection correlations to natural convection problems involving vertical/horizontal plates, vertical/horizontal cylinders, spheres, channels, and rectangular enclosures
  • Determine the overall heat transfer coefficient (U) for heat exchange surfaces
  • Perform design and performance calculations using the LMTD and -NTU methods for concentric tube, shell-and-tube, and cross flow heat exchangers
  • Determine total emissivity, total absorptivity, total reflectivity, and total transmissivity from given spectral data and band emission factors
  • Determine view factors for simple 2D and 3D geometries using tables, graphs, inspection, and the view factor relations (i.e., reciprocity, summation, & subdivision)
  • Determine radiation heat transfer between diffuse, gray surfaces for two- and three-surface systems
  • Analyze radiation shields to predict heat transfer reduction
  • Set-up energy balance equations for multimode heat transfer problems with N-surface radiation enclosures

* Even though this exam will focus on natural convection, heat exchangers, and radiation, it is expected that you can also: set up a control volume or surface energy balance, define thermal resistances and use the thermal circuit approach to solve systems, and compute appropriate convection coefficients for forced convection situations.