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.
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Mechanical Injection System: Used to inject fuel into the combustion chamber. Fuel speed > air speed at delivery point to atomize fuel. Amount of fuel delivered into the air stream going into the engine is controlled by pump which forces the fuel under pressure. A device used to initiate and control the combustion process is called Mechanical Injection System. Functional Requirements of Injection System: Metering of Fuel: Used to control fuel to meet speed and load requirements of the engine. Injection Timing: Have proper injection timing to obtain max. power, fuel economy and proper burning. It is done by Camshaft or Push rod (Rocker Arm) Mechanism . Proper Control of Injection Rate: To get desired heat release pattern during combustion. Proper Atomization of Fuel: Proper making of droplets to make best Air/Fuel mixture. Proper Spray Pattern: Distribution of droplets to ensure rapid mixing of fuel & air. Uniform Distribut...
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