Details
Torque or Turning Force: It is the total amount of force which is requi red to create acceleration on moving substance. Couple: Two forces those acts on equally,parallely equally,parallely & oppositely on o n two separate points p oints of same material. oment: It is the amount of moving effect which is gained for action of turning force. !tress: It is the force that can prevent equal & opposite force. That means, it is the preventing force. If one force acts on outside of a material, then a reactive force automatically acts to protest that force. The amount of reactive force per unit area is called stress. e.g. Tens Tensile ile !tress, Compressive !tress, Thermal !tress. !train: If a force acts on a substance, then in that case if the substance would deform. Then the amount of deformation per unit length of that substance is called strain. !pring: It is one type of device which is being distorted under certain amount of load & also can also go to its original face after the removal of that load. Its function: To store energy. To absorb energy. To control motion of two elements. !tiffness: "oad per unit deflection. The amount of load required to resist the deflection. !pecific #eight: #eight per unit volume of the fluid. !pecific $olume:
$olume per unit mass of the fluid. !pecific %ravity: It is the ratio of specific weight of required substance to specific weight of pure water at degree centigrade temperature. !pecific heat: The amount of heat required to increase ' unit temperature of ' unit mass. $iscosity: (ynamic $iscosity: The amount of resistance of one layer of fluid over other layer of fluid. )inematic $iscosity: It is the ratio of dynamic viscosity to density. *uoyancy: #hen a body is immersed in a liquid, it is lifted up by a force equal to weight of liquid displaced by the body. The tendency of liquid to lift up an immersed body is buoyancy. The upward thrust of liquid to lift up the body is called buoyancy force. *ernoulli+s quation: -/ 0$12g 03 4 Constant #here, - 4 pressure,$ 4 velocity,3 4 (atumn 5ead
(evices for fluid: $enturimeter: It measures discharge of fluid. 6otches : It measures discharge of fluid. 7rifice meter: It measures discharge of fluid. -itot tube : It measures velocity of fluid.
ach 6umber: It is the ratio of the velocity of fluid to the velocity of sound.
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Fluid dischargeFluid flow: =uantity of fluid flowing per second. through a section of pipe through a section of channel< =4>$ where, $4 velocity of fluid,>4 cross8sectional area of pipechannel 6ote: 'm? 4 '@@@ "' cusec 4 ' ft?sec' ft 4 @.A@B m 5ydraulic achine: Turbine,-ump,Compressor etc. (raft tube: It attaches with reaction turbine . Its function is to reduce energ y loss from reaction turbine & it also reduce pressure at outlet which is must blow the atmospheric pressure. Themodynamics "aw: 3eroth "aw First "aw of Thermodynamic !econd "aw of thermodynamic 3eroth "aw: If two body are in thermal equilibrium with a third body then these two body are also in thermal equilibrium with each other.
First "aw of Thermodynamics: In a closed system, wor deliver to the surrounding is directly proportonal to the heat taen from the surrounding.>nd also, In a closed system, wor done on a system is directly proportonal to the heat deliver to the surrounding.
!econd "aw of Thermodynamics: It is impossible to mae a system or an engine which can change '@@ percent input energy to '@@ percent output.
ntropy: It is a thermodynamic property. ds 4 dqT where, ds 4 change of entropy, dq 4 change of heat, T 4 Temperature. In adiabatic process, entropy can not change. >ctually,lacing or mal8adroitness of tranfering energy of a system is entropy.
Calorific $alue of fuel: It us the total amount of heat obtained from burning ' g solid or liquid fuel.
*oiler!team %enerator: It is a clossed vessel which is made of steel. Its function is to transfer heat to water to generate steam.
conomiser: It is a part of boiler. Its function is to heat feed water which is supplied to boiler.
!uperheater: It is a part of boiler. Its function is to increase temperature of steam into boiler.
>ir8-reheater: It is a part of boiler. Its funtion is to preheats the air to be supplied to furnace and it recover heat from eDhaust gas.
*oler (raught: It is an important term for boiler. It is the difference of pressure above and belo w the fire grate. This pressure difference have to maintain very carefully inside the bolier. It actually maintaind the rate of steam generation. This depends on rate of fuel burning. Inside the boiler rate of fuel burning is maintained with rate of entry fresh air. If proper amount of fresh air never entered into the boiler, then proper amount of fuel inside the boiler never be burnt. !o, proper fresh air enters into the boiler only by maintaining boiler draug ht.
6oEEle: 6oEEle is a duct of varying cros8sectional area. >ctually, it is a passage of varying cross8 sectional area. It converts steam+s heat energy into mechanical energy. It is one type of pipe or tube that carrying liquid or gas.
!cavenging: It is the process of removing burnt gas from combustion chamber of engine cylinder.
!upercharging: >ctually, power output of engine depends on what amount of air enter into the engine through intae manifold. >mount of entry aiy if increased, then must be engine speed will increased. >mount of air will be increased by increasing inlet air density. The process of increasing inlet air density is supercharging. The device which is used for supercharging is called supercharger.!uperchargeris driven by a belt from engine crashaft. It is installed in intae system.
Turbocharging: Turbocharging is similar to the supercharging. *ut in that case tubocharger is installed in eDhaust system whereas supercharger is installed in intae system. Turbocharger is driven by force of eDhaust gas. %enerally, turbocharger is used for 28stroe engine by utiliEing eDhaust energy of the engine, it recovers energy other wise which would go waste.
%overneor: Its function id to regulate mean speed of engine when there are variation in the load. If load incrases on the engine, then engine+s speed must decrease. In that case supply of woring fluid have to increase. In the otherway, if load decrease on the engine, then engine+ speed must increase. In that case supply of woring fluid have to decrease.%overnor automatcally, controls the supply of woring fluid to the en gine with varying load condition.
Flywheel: It is the one of the main parts of the I.C. engine. Its main function id to store energy in the time of woring stroe or eDpansion stroe. >nd, it releasesenergy to the cranshaft in the time of suction stroe, compression stroe & eDhaust stroe. *ecause, engine has only one power producing stroe.
ating of fuel: !.I. ngine: 7ctane number. 7ctane number indicates ability of fuel to resist noc. C.I. ngine: Cetane 6umber. Cetane number indicates ability of ignition of diesel fuel. That means, how much fast ignites diesel fuel.
!toichiometric ratio: It is the chemically correct air8fuel ratio by volume. *y which theoratically sufficient oDygen will be gotten to burn all combustible elements in fuel completely.
5eat Transfer: It is a science which deals with energy transfer between material bodies as a result of temperature difference.There are three way to heat transfer such as8 ConductionConvectionadiation
Thermal Conductivity: It is the quantity of heat flows between two parts of solid material by conduction. In this case following consideration will be important fact8 Time888888 ' sec >rea of that solid material88888888 ' m1 Thicness of that solid material888888 'm Temperature difference between two parts of that material888888 '
5eat Dchanger: It is one type of device which can transfer heat from one fluid to another fluid. Dample8 adiator, intercooler, preheater, condenser, boiler etc.
efrigeration: It is the process of removing heat from a substance. >ctually, eDtraction of heat from a body whose temperature is already below the temperature of its surroundings.
' tonne of refrigeration: It is amount of refrigeration effect or cooling effect which is produced by uniform melting of ' tonne ice in 2 hours from or at @ degree centigrade or freeEing ' tonne water in 2 hours from or at @ degree centigrade.
5umidification: It is the addition of moisture to the air without change dry bulb temperatur.
(ehumidification: It is the removal of moisture from the air without change dry bulb temperature.
%ear Train: eshing of two or more gear. It can transmit power from one shaft to another shaft.
5eat Treatment: 7peration involving heating and cooling of a metal in solid state for obtaining desirable condition without being changed chemical composition.Its obGect8increase hardness of metal.increase quality of metal heat, corrosion,wear resistance quality
Ferrous etal: '. Cast Iron 8 28;.;H<C, !i, n, -, ! 2. !teel 8 @82<C A. #rought Iron 8 JJ.K Fe
6on8Ferrous etal: '. *rass 8 Cu03n< 2. *ronEe 8 !n0Cu< 888888 Tin *ronEe !i0Cu< 8888888 !ilicon *ronEe
>l0Cu< 8888888 >luminium *ronEe
>llowance: It is the difference between basic dimension of mating parts. That means, minimum clearance between mating parts that can be allo wed.
Tolerance: It is the difference between upper limit of dimension. It is also the permissible variation above and below the basic siEe. That means maDimum permissible variation in dimensions.
Clearance: It is the difference in siEe between mating parts. That means, in that case the outside dimension of the shaft is less than internal dimension of the hole.
!tiffness: It is the ability to resist deformation.
Toughness: It is the property to resist fracture.
Fatigue: #hen a material is subGected to repeated stress below yield point stress, such type of failure is fatigue failure.
6uclear Fission: It is a nuclear reaction by which one big nucleous divided into two or more nucleous.
6uclear Fussion: It is also a nuclear reaction by which one big nucleous will produced by adding two small nucleous.
#elding: It is the process of Goining two similar or dissimilar metal by fusion.
>rc #elding 8 L need (.C current L produced ;@@@8H@@@< (egree Centegrade Temperature %as #elding 8 L 7Dy 8 acetylene flame Goin metals L 7Dygen & acetylene gas wors L produced A2@@ (egree Centegrade Temperature
achine Tool: It is the power driven tool. It cut & form all inds of metal parts. Dample 8 '. "athe2. (rill -ressA. !haper. -lanerK. %rinding;. ilingH. *roachingB. *oring
Cutting Tool:
Tool aterials for Cutting Tool: '. 5igh Carbon !teel 2. 5igh !peed !teel #0Cr0$< A. Carbide # Carbide0Ti Carbide0Co Carbide< IndeDing: It is the method of dividing periphery of Gob into equal number of division. >ctually, it is the process of dividing circular or other shape of worpiece into equal space, division or angle. Mig: It is one type of device which hold & locate worpiece and also guide & control cutting tool. It uses in drilling, reaming and tapping. FiDture:
It is one type of device which hold and locate worpiece. It uses in miling, grinding, planning & turning.
