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 ).
It is the study of mechanics of body i.e. forces and their effects on deformable solids under different loading conditions.
Deformable Body Mechanics:
It is the study of non-rigid solid structures which deform under load.
Deformation/Distortion ⇾ change of shape and size OR have some relative displacement or rotation of particles. It happens when we apply combined load.
Rigid Body Motion ⇾ Translation or rotation of particles but having constant distance between particles.
Since deformation occur at particular load. Below this load, every body is considered as rigid body.
Types of Load:
Point Load ⇾ Load apply on a single point i.e. concentrated load.
Uniformly Distributed Load (UDL) ⇾ Load remains uniform throughout an area of element like beam.
Varying Distributed Load (VDL) ⇾ Load varies with length with constant rate.
Moment ⇾ It measures the tendency of a body to rotate.
Distribution Of Forces:
Normal Force (N) ⇾ Force applied perpendicular to the area and is developed when external loads tend to push or pull the body.
Shear Force (V) ⇾ Force applied parallel to the area and is developed when external loads tend to slide.
Torsional Moment OR Torque (T) ⇾ External Force tends to twist a body.
Bending Moment (M) ⇾ External loads that tend to bend due to transverse loading.
Important Terms:
Transverse Loading ⇾ Load applied perpendicular to the axis of body.
Supports ⇾ Elements used to restrict motion of member.
Reactions⇾ These are forces produced due to those restrictions.
Degree of Freedom (DOF) ⇾ Number of independent coordinates in which an object can move.
Equilibrium of Forces ⇾ It prevents body from translating and having accelerated motion.
Equilibrium of Moment ⇾ It prevents body from rotating.
Procedure of Analysis:
Resultant internal force are required and can be found by the Method of Sections (require determinations of support reactions and resultant internal loads using equilibrium equations).
Steps are as follows:
Draw free-body diagrams using all external distributed loadings, couple moments, torques, forces at exact locations.
Determination of support reactions.
Determination of resultant internal force and moments using equilibrium equations.
References:
Material from Class Lectures + Book named Engineering Mechanics of Materials by R.C. Hibbeler (10th Edition) + my knowledge.
TAPING CORRECTIONS There are two types of corrections depending upon the type of errors in tape due to the different conditions. 1. Systematic Errors : Slope Erroneous tape length Temperature Tension Sag 2. Random Errors : Slope Alignment Marking & Plumbing Temperature Tension & Sag 1. Temperature Correction It is necessary to apply this correction, since the length of a tape is increased as its temperature is raised, and consequently, the measured distance is too small. It is given by the formula, C t = 𝛼 (T m – T o )L Where, C t = the correction for temperature, in m. 𝛼 = the coefficient of thermal expansion. T m = the mean temperature during measurement. T o = the tempe...
Introduction Existence of perfect crystals (without defects) are ideal. Instead, we have kinds of imperfection. Ques: Why study imperfections in Solids? When pure metals alloyed (addition of impurities ) like Sterling Silver ↣ 92.5 % Ag and 7.5 % Cu , Cartridge Brass ↣ 70 % Cu and 30 % Zn . These impurities play an important role in semiconductors properties, steel composition, etc. Atomic defects are responsible for reduction gas pollutants emissions in automobiles. Ques: How polluting gases converted into non-pollutant gases? Ans: Molecules of pollutant gases become attached to surface defects of crystalline material. Hence it convert into less-polluting substance. Types of Defects (Imperfections) in Solids There are four types of defects: Point (or Zero-D) Defects Linear (or 1-D) Defects Planar (or 2-D) Defects Bulk (or 3-D) Defects 1. Point Defects It is defined as, " defects associated with one or two atomic position " . Point defects are further divided into tw...
Reynolds Number: Reynolds Number is the ratio of Inertial forces to the Viscous forces. By knowing this number, one can describe the flow whether the flow is laminar, turbulent or transitional flow. There are three possibilities of the range of Reynolds Number: If Reynolds number < 2100 or 2300 ⟺ Laminar Flow If Reynolds number > 4000 ⟺ Turbulent Flow If 2300 < Reynolds number < 4000 ⟺ Transitional Flow In case of different shapes other than circle, the formula for Reynolds Number remain the same however diameter involves in the formula become Hydraulic Diameter which is given by: For pipe: Critical Reynolds Number ⟾ The Reynolds number at which the flow becomes turbulent Re cr For different shapes, the hydraulic diameters are given by: Completely Filled Flow In Closed Channel: If pipe is is considered to filled completely with closed channel, then following are the conditions which...
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