Radiation Heat Transfer

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View Factor Orientation (or View factor or shape factor) plays an important role in radiation heat transfer. View factor is defined as, "fraction of radiation leaving surface 'i' and strike 'j' ". Summation Rule (View Factor) If there is are similar surfaces 'i' and 'j' , then: Blackbody Radiation Exchange Radiation Exchange between Opaque, Diffuse, Gray surfaces in an Enclosure 1. Opaque 2. Surfaces 3. Two surface enclosure Radiation Shield It is used to protect surfaces from radiation act like a reflective surface. References: Material from Class Lectures + Book named Fundamentals of Heat and Mass Transfer by Theodore L. Bergman + My knowledge.  Photoshoped pics  are developed.  Some pics and GIF from Google.   Videos from YouTube ( Engineering Sights ).
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Material Property Relationships & Theory of Elastic Failure

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Material Property Relationships

There are three principles which inter-related (applies to Uniaxial direction):

  1. Hooke's Law
  2. Poisson's Ratio
  3. Principle of Superposition
The relationship between E, ν, G is:

Dilatation Rate

When an elastic material is subjected to normal stress, its volume will change. The change in volume is given by:

Theory of Elastic Failure or Yielding

  • When dealing with design of structures/components  ➞  physical properties are found using simple stress conditions (most usual tensile test).
  • Important for determining allowable working stresses to avoid failure.
These theories are for predicting the behavior of materials adequate correlation b/w estimated component life and under service load condition for ductile/brittle material applications.
  1. Max. Principal Stress Theory (Rankine)
  2. Max. Shear Stress Theory (Guest-Tresca)
  3. Max. Principal Strain (Saint-Venant)
  4. Total Strain Energy per unit volume (Haigh)
  5. Shear Strain Energy per unit volume (Maxwell-Von-Misses)

References:

  • Material from Class Lectures + Book named Engineering Mechanics of Materials by R.C. Hibbeler (6/9th Edition) + my knowledge. 
  • Pics and GIF from Google Images.  
  • Videos from YouTube (Engineering Sights).

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