Presentation on theme: "Technical Seminar on Refrigeration & Air Conditioning"— Presentation transcript:
1Technical Seminar on Refrigeration & Air Conditioning Presented byManmatha Kumar GiriEEUnder the Guidance ofMr. Debashisha Jena
2INTRODUCTIONThe electrical energy is utilized by converting it into one form or other for getting suitable output from it.The utilization electrical energy for the refrigeration and air conditioning is fast replacing the old methods.
3WHAT IS REFRIGERATION & AIR CONDITIONING ? The process of reducing the temperature of a body from the general level of temperature of surroundings is called refrigeration.Air-conditioning means control of temperature,humidity,purity and movement of air.The working conditions and comfort for human beings is improved by air-conditioning.The temperature is brought down during summer and increased during winter without causing any discount.
4REFRIGERATORThis is the machine by which the temperature of substances is lowered by storing them in this machine.
5PRINCIPLEA refrigerator works on the principle of cooling caused by evaporation.when we dip our finger in petrol or spirit,and the finger is taken out cooling is felt. This is because when petrol or spirit evaporates it draws heat from the finger thus cooling it.
6REFRIGERANTThe refrigerant is generally a gas which circulated through different stages to extract the heat from the substances.The various refrigerants used are carbon dioxide(CO2),sulphur dioxide(SO2),ammonia(NH3),Freon(F-12) and methyl chloride etc.
7VAPOUR COMPRESSION CYCLE The main purpose of vapour compression cycle is to remove heat from the refrigerant by putting it into a stage for reuse.The various stages are1.compression2.condension3.expansion4.evaporation
8APPLICATIONThe vapour compression refrigeration cycle is employed for the following purposesDomestic refrigerator,Water cooler,Air conditioner,Ice plant,cold storage etc.
9DOMESTIC REFRIGERATOR The actual lay out of domestic refrigerator is shown in figure below.
10ELECTRICAL CIRCUIT OF REFRIGERATOR The main parts of the electrical circuit are shown in figure belowThe various parts are1. motor compressor unit2. starting relay3. thermostat4. overload protector5. cabinet light6. drier assembly.
11MOTOR COMPERESSOR UNIT The motor is a single phase capacitor start motor.The actual capacity of the motor depends upon the size of the refrigerator.But generally the horsepower of motors varies from 7/32 H.P. to 1/8 H.P.Mostly the motor and compressor are in one unit and is known a sealed unit.
12STARTING RELAYThe motor is operated by this relay which is also called motor protective relay.It essentially consists of a plunger on which a coil is wound .The figure below shows the arrangement:
13THRMOSTATA thermostatic switch is used on all the household refrigerators by which the temperature is controlled, and it is called thermostat.The construction of a thermostat used in a refrigerator is shown in figure below:
14OVERLOAD PROTECTORThis is a thermal device which opens the circuit of the motor when overloaded and is called overload protector.The figure below shows the enlarged view of a overload protector.
15CABINET LIGHT This circuit contains a lamp and a switch. The switch is called door switch and so installed that when the door is closed,the bulb remains off.When the door is opened, the bulb remains on.
16DRIER ASSEMBLYThis assembly is not employed on all the domestic refrigerators.This is a high resistance wire passing around the drier to remove the moisture from the refrigerator.This is connected across the supply by the thermostat.
17AIR-CONDITIONERThe room air conditioner is used to condition the air of a particular space occupied by the human beings i.e. office, room etc.It has automatic operation to control and maintain the humidity of air.There are two parts divided by a partition with a small opening at the top as1.outdoor part2.indoor part
18AIR-CONDITIONERThe complete operation of an air conditioner can be studied under these sub headings-1.vapour compression cycle2.air circulation3.electrical circuitThe figure below shows a room air conditioner
19CONCLUSIONThe electrical energy is utilised by converting it into one form or the other form for getting suitable output from it.The utilization of electrical energy for the refrigeration and air conditioning is fast replacing the old methods.Refrigeration and Air Conditioning has become a necessity in every sphere of human utility and industrial set-ups.