THE NEW CONCEPT OF REFRIGERATION USING HIGH INTENSITY SOUND WAVE IS DESCRIBED IN MY PPT.

1. A Seminar
on
“THERMO ACOUSTIC REFRIGERATION”
By
SHOEB.M.KHAN
(T120421108)
Guided by
Prof. R.CHINGALE SIR
Department of Mechanical Engineering
SINHGAD INSTITUTE OF TECHNOLOGY
LONAVALA
[2016 - 2017]

2. THERMO ACOUSTIC
REFRIGERATION

3. Introduction
 Refrigeration :The process of cooling the space by removing the heat and
maintaining it below room temperature is known as Refrigeration.
 Now a days the need of refrigeration is increases for various application like
house hold ,medical,army,and for space application this refrigerator works on
VCR cycle.
 The Thermo acoustic refrigerator deal with the sound energy and conversion of
it into heat energy.
 When sound wave travel through any medium it exert the force on that
medium, and hence compression of that occurs this is used in this project.

4. SR.NO TITLE YEAR AUTHOR METHOD
USE
1 Environmental motivation to
switch to thermo acoustic
refrigeration
2009 Mattew.E.Poese Heat transfer
2 Design and construction of a
traveling wave thermo acoustic
refrigerator
2011 Nathon thoman
weiland
Gas as a
medium
3 Thermo acoustic power effect on
the refrigeration
2003 D.A.Geller Maylar stack
4 Experimental study on the
performance of the thermo
acoustic refrigeration
2009 Mark.P.Telez Force
circulation
5 Design of thermo acoustic
refrigerators
2001 Richard Raspet Pumping
LITERATURE REVIEW:

5. PROBLEM DESCRIPTION:
 In present the use of refrigerator is increases ,our conventional refrigerator
works on vapor compression cycle(VCR).
 The refrigerant used in VCR cycle is a Chloro-fluoro carbon which is very
harmful for our environment as well as for human life also.
 In addition with this VCR cycle uses Compressor which is considered as a
heart of refrigerator ,this required more electrical energy for their operation.
 To overcome this two major issue new concept for refrigerator is used in which
compressor and harmful refrigerant is eliminated.

6. VAPOUR-COMPRESSION REFRIGERATION
CYCLE
METHODOLOGY:

7. ACOUSTICAL THEORY
 Acoustic is the sound wave having high frequency. The sound wave
is considered as a pressure wave ,i.e. when they travel through any
medium it exerts the force on that medium and compression of
medium occurs.
 The sound wave propagate as a sine wave which changes its
magnitude and direction w.r.t time. And hence when they travel
simultaneously compression and expansion of medium occur.
 This important property of acoustic is used in acoustic refrigerator.


8. CONSTUCTION OF THERMO ACOUSTIC REFRIGEATION:
 It consist of 4 parts:
1.Acoustic drive (Loudspeaker) 3.Stack
2.Resonator (Glass tube) 4.Seals

9. ACOUSTIC DRIVER:
 It is device which produce high frequency sound wave.
 Acoustic driver converts the electrical energy into sound energy.
 This required maximum 15 watt of electrical energy.

10. RESONATOR :
 Resonator is a long tube ,the material used for tube is Acrylic,
The Acrylic material is used as it resist heat conductivity and hence performance is
increased
1. The length of resonator should be 70cm
2. The internal diameter should be 6.3cm
3. And the thickness of tube should be 6mm

11. STACK:
 Stack is a device which consist of number of thin plate arranged parallel
to each other.
 The cross section area of each plate is very less, it is used to increase the
surface area
 So that large amount heat can be absorbed.
 In between two plate there is a small space, this space is utilized for expansion
of high pressure gas

12. Seals:
The seals are used to ovid the leakage of heat from tube as well as
it is also used to ovid the leakage of high frequency sound wave
WORKING MEDIUM:
 In thermo acoustic refrigeration the inert gases are used as a working
medium.
 Because of inert gases it does not pollute environment.
E.g-Helium,Argon,etc

13. WORKING OF THERMO ACOUSTIC REFRIGEATION

14.  In the assembly of acoustic refrigeration, the tube is filled with the inert gasses, the
one end of tube is connected to loudspeaker and another end of tube is closed.
 The stack is placed inside the tube in between loudspeaker and closed end .
 When the loudspeaker start it converts electrical energy into sound energy ,this
sound wave travel through the gas, and it get compressed due to which its
temperature and pressure get increases.
 When the compressed gas suddenly strikes to solid surface i.e. Stack it gives its
total heat to left end of stack at constant pressure and its temperature get
decreased.
 Simultaneously the compressed gas try to escape through the space in between
two plate, because of which the compressed gas expand and its temp. again
decreases to excursion temperature which is very low temperature.
 The gas gives its coldness to right end of stack when they leave .and by using of
cold heat exchanger we can extract coldness and gives to evaporator.

15. ADVANTAGES:
It does not produce any harmful gases.
It required less power for its operation.
Compact in size.
DISADVANTAGES:
It produce unwanted vibration.
Proper sealing is required
APPLICATIONS:
used for space application:
1) Satelite
2)Space station

16. CONCLUSION:
Thermo acoustic refrigeration is eco friendly and does not produce any
harmful gasses also it does not harmful for human being as well as it
required less power supply for its operation.
To ovoid the harmful pollutant in our environment we have to change our
refrigeration process.
Hence Acoustic Refrigeration is best alternative for future purposes.