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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Moment of Inertia

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Moment of Inertia:

It is defined as;
The resistance to bending or change in its rotation.

It is also called 2nd Moment of Inertia.




The formula for the Moment of Inertia is given by:



Parallel-Axis Theorem For an Area:

It can be used to find the moment of inertia of an area about any axis that is parallel to an axis passing through the centroid and about which the moment of inertia is known.


From the definition of Moment of Inertia:


  • The first integral represents the MOI of an area about the centroidal axis Ix.
  • Second integral (a mathematical quantity) is zero since the X` axis passes through the centroid C itself.
  • The third integral represents the total area A.


Radius of Gyration of an Area:

(Gyration: A rapid movement in a circle or spiral).

Radius of Gyration is defined as;
Distance from a given axis upto a point where the entire area is assumed to be concentrated.
It is a quantity use for the design of columns in Structural Mechanics.


Moment of Inertia for Composite Areas:

A composite area consists of a series of connected simpler shaped Bodies. The MOI of these bodies about any axis is equal to the algebraic sum of the moments of inertia of all its parts.


Product of Inertia for an Area:

Product of Inertia is used to determined the maximum and minimum values of MOI which are important for Designing structural and mechanical members such as beams, columns, shafts, etc.

References:

Comments

  1. AnonymousJanuary 11, 2020 at 9:25 AM

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    This will make you understand the basic concepts related to Statics and you can match it with the standard syllabus with this blog

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