KALI CHARAN NIGAM INSTITUTE OF
TECHNOLOGY, BANDA
LECTURE
ON
INTRODUCTION TO REFRIGERATION
FUNDAMENTAL OF MECHANICAL ENGINEERING (BME101)
BY : DEEPAK KUMAR YADAV
ME DEPARTMENT

REFRIGERATION
The term refrigeration may be defined as the
process of removing heat from a substance under
controlled conditions.
In other words the refrigeration means a
continued extraction of heat from a body whose
temperature is already below the temperature of
its surrounding.

REFRIGERATING EFFECT
The rate of heat absorbed from a body to be
cooled is called refrigerating effect.
Refrigerating effect : It is amount of heat energy
removed per unit time from the space to be cooled
by the refrigeration process. It is expressed in KW
or KJ/s.

TON OF REFRIGERATION
 The practical unit of refrigeration is expressed in terms
of ‘ ton of refrigeration’ (TR).
A ton of refrigeration is defined as amount of
refrigerating effect produced by the uniform melting of
one ton (1000kg) of ice from and at 0oC in 24 hours.
Latent heat of ice = 335
Therefore one ton of refrigeration
1 TR = 1000×335 KJ in 24 hr
=
= 232.6 KJ/min
In actual practice, one ton of refrigeration is taken as
equivalent to 210 KJ/min or 3.5 KW.

HEAT ENGINE
 Heat engine is the device
which converts chemical
energy of fuel into heat
energy and this heat energy is
utilized converting it to
mechanical work.
 Thermal efficiency : The ratio
of net work output to the
entire amount of heat
supplied to the working
medium.

THERMAL EFFICIENCY OF HEAT ENGINE
The work extracted is equal to the difference
between the heat energy transferred from the hot
reservoir and the heat exhaust into cold reservoir:
 Thermal efficiency =

HEAT PUMP
Heat pump is a device is used to maintain a
higher temperature as compared to surrounding
by supplying heat to system.
 Coefficient of Performance (COP):
COP of a heat pump is expressed
by ratio of amount of heat delivered
To hot body to amount of work
required to be done on the system

REFRIGERATOR
Refrigerator is a device is used to maintain a lower
temperature as compared to surrounding by
absorbing heat from the system.

THANK YOU