AIR COOLER :

AIR COOLER

    Air cooler works on the principle of evaporating cooling. It is generally used in dry climate as such it is sometimes called as desert cooler. In this case water is used as a cooling medium. The temperature of air is decreased (I.e. sensible heat is removed) by the water when air is brought in contact with the water. Water absorbs heat from the air and evaporates. To compensate loss of water due to evaporation, make up of water is added.

FUNCTION OF AIR COOLER

The basic components are fans, water pump and pads through which air is enter the cooler. The electric driven pump pumps the water from the bottom tank to the top headers. The header have holes through which the water trickles down and pass through pads fitted on three sides of the cooler. Air sucked through pads from three sides gets cooled . The cool air is discharged by the motor driven fan in to the room or space to be cooled. The direction of air flow can be adjusted with the help of grills fitted on the discharge side of the cooler. 

PRECAUTION S

For better performance pads to be changed every year and water tank should be cleaned from time to time

Law of Parallelogram of Forces

Law of parallelogram of forces

The law of parallelogram of forces is used to determine the resultant*of two forces acting at a point in a plane. It states "If two forces acting at a point be represented in magnitude and direction by the two adjacent sides of a parallelogram, them their resultant is represented in magnitude and direction by the diagonal of the parallelogram passing through that point. "

                

Law of conservation of energy

Law of conservation of energy

    It states that the energy can neither be created nor destroyed through it can be transformed from one form to another form. The second statement of this law is :

   "The total energy possessd by a body remains constant provided no energy is added to or taken from it"

Where. 

         W= Weight of body

         m=Mass of body=W/g

          h= Height of tower

ANGLE OF REPOSE ?

Angle of Repose! 

     The angle of repose is defined as the maximum inclination of a plane at which a body remains in equilibrium over the inclined plane by the assistance of friction only.

                

  Where

            

    R=Normal reaction acting at right angle to the inclined plane

    a=Inclination of the plane with the horizontal

    F=Frictional force acting upwards along the plane

What is the function of condenser ? How do you classify the condenser ?

Function of condenser

The function of condenser is to remove heat from the vapour refrigerant which is discharged from the compressor and convert it into liquid refrigerant. This process of converting vapour into liquid is called condensation 

Classification of condenser

   1. Air cooled condensers. 

   2.water cooled condensers. 

   3.Evaporative condensers. 

LUBRICANTS

LUBRICANTS

Lubricants are used in bearings to reduce the friction between contacting surfaces and to carry away the heat generated by friction

The commonly used lubricants are classified as:
1. Liquid (Load oil, mineral oil etc.) 

2.Semi-solid (Grease) 
3.Solid (Graphite ) 

PROPERTIES OF A GOOD LUBRICANTS:

The desired properties of good lubricants are :

      1.They should have sufficient viscosity

      2.They must possess sufficient oiliness

      3.During operations the lubricants must not produce any gases 

newtons third law

Every action these is an equal and opposite reacton

CLASSIFICATION OF A FORCE SYSTEM ?

CLASSIFICATION OF A FORCE SYSTEM? 

                  Force system

   (1) Coplanar    (2) Non-coplanar

(1) Coplanar. 

 1.Collinear.

 2.Concurrent.

 3.Parallel.

 4.Non-Concurrent, non-parallel. 

 (2) Non-coplanar. 

  1.Concurrent.

  2.Parallel.

  3.Non-concurrent , non-parallel. 

EXPLAIN LAMIS THEOREM! ?

State lami's theorem ! 

   It states that,"If three  forces acting at a point are in equilibrium, each force will be
proportional to the sine of the angles between the other two forces ".

Write the classification of air-conditioning systems?

Write the classification of air-conditioning systems

The air conditioning systems are classified based on different criteria as given below. 

A.  According to the season of the year:

     (1) Summer air-conditioning. 

     (2) Winter air-conditioning. 

     (3) Year round air-conditioning. 

B.  According to the application of the system:

      (1) comfort air-conditioning. 

      (2) Industrial air-conditioning. 

C. According to the location of equipment:

      (1) unitory system. 

      (2) Central Station system. 

      (3) Combination system. 

Define air conditioning?

Define air conditioning!
   
   Air conditioning is defined as the process of simultaneously control of temperature, humidity, cleanlines and distribution of air in the space to be conditioned as per requirements.

What is refrigeration effect?

What is refrigeration effect!

The refrigeration effect is defined as the cooling effect produced in a space or product in a given time is called of refrigeration effect. and it is expressed in KJ/s or J/s