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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Elastic Strain Energy

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Strain Energy or Resilence 

It is defined as, "energy absorbed in a body when deformation is done on material".
  • Depend on Material.
Strain Energy Density is defined as, "strain energy per unit volume".
  • Independent of material.
  • Used to tell which deformation component is greater with direction.
  • If greater in specific direction  ↔  crack propagates in that direction.
  • Stress (in Dynamic effect)  >  Stress (in Static effect)

Types of Loading

Energy Conservation

It states that, "Energy can neither be created nor be destroyed but can transfer in other forms".
  • We only deal with mechanical energy.
  • External work = internal energy or strain energy.
  • If this external force is in elastic limit, strain energy restores body back to its original undeformed position.
Note:

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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