My final year project

1. By:
Project Guide: E.Nikhil Kumar(12000T0338)
Anil Kumar M.Aparna (12000T0304)
P.Jagan (12000T0314)
k.Sirisha (12000T0353)
M.Ram Kumar(12000T0321)

2. Aim
 The aim of our project is to produce the refrigeration
effect using both Bell-Coleman cycle and Vortex tube.
 In this project we mainly concentrated on the cold end
temperatures of Vortex tube through which
refrigeration effect is produced. We fabricated four
different vortex tubes with different dimensions,
number of nozzles, orifice & Venturi and compared
their COP’s and cooling rates.
 Our project gives the scope of replacing conventional
refrigeration systems with air refrigeration system

3. Introduction
 Air refrigeration system generally uses air as medium, whereas
other refrigeration systems use refrigerants (Freon’s, ammonia
etc.,) as medium. Since air is used as refrigerant no damage to
atmosphere is done. By using other refrigerants damage to
atmosphere such as ozone layer depletion takes place.
Compression of air needs much power compared to
compression of refrigerants. This system produces low COP
because of which it has become obsolete.
 Other refrigeration systems have high COP but have severe
impact on atmosphere. Moreover these refrigerants are too
expensive and handling of these refrigerants is difficult.

4. Bell-Coleman cycle refrigeration
system
Components of Bell-Coleman cycle refrigeration system:
 Air Compressor
 Heat Exchanger
 Air Regulator
 Evaporator (Cabin)

5. Working of Bell-Coleman cycle
1. Isentropic compression process
2. Constant pressure cooling process
3. Isentropic expansion process
4. Constant pressure expansion process

6. Working of Bell-Coleman cycle
1. Isentropic compression process: The cold air from the
refrigerator or atmosphere is drawn into the compressor
cylinder where it is compressed isentropically in the
compressor as shown by the curve 1-2 on p-v and T-s
diagrams. During the compression stroke, both the pressure
and temperature increases and the specific volume of air at
delivery from compressor reduce from v1 to v2. We know that
during isentropic compression process, no heat is absorbed or
rejected by the air.
2. Constant pressure cooling process: The warm air from the
compressor is now passed into the cooler where it is cooled
at constant pressure P3 (equal to P2), reducing the
temperature from T2 to T3 (the temperature of cooling water)
as shown by the curve 2-3 on p-v and T-s diagrams. The
specific volume also reduces from v2 to v3.

7. 3. Isentropic expansion process: The air from the cooler is now
drawn into the expander cylinder where it is expanded
isentropically from pressure P3 to the refrigerator pressure P4
which is equal to the atmospheric pressure. The temperature of
the air during expansion falls from T3 to T4 shown by the curve
3-4 on p-v and T-s diagrams. The specific volume of air at entry
to the refrigerator increases from v3 to v4. We know that during
isentropic expansion of air, no head is absorbed or rejected by
the air.
4. Constant pressure expansion process: The cold air from the
expander is now passed to the refrigerator where it is expanded
at constant pressure P4 (equal to P1). The temperature of air
increases from T4to T1. This process is shown by the curve 4-
1on p-v and T-s diagrams. Due to heat from the refrigerator, the
specific volume of the air changes from v4 to v1.

8. Apparatus required
 Digital Thermometers – 2
 Copper tube (Heat exchanger) – 1
 Air Compressor
 Air regulator
 Cabin
 Digital Anemometer
 Connecting pipes

9. Compressor

10. Heat Exchanger

11. Air Regulator

12. Cabin

13. BELL COLEMAN CYCLE EXPERIMENTAL
SETUP

14. Procedure of experiment
 For different compressor pressures after expansion, We
calculated the Cooling effects and COP’s by using
evaporator’s inlet and outlet temperatures.
 We plotted the graphs for the same results
1) Pressure after expansion versus cooling effect
2) pressure after expansion versus COP

15. Working Video

18. Observations from Graphs
It is found out that
 As inlet pressure increases, COP of Bell Coleman cycle
increases.
 As inlet pressure increases, cooling effect of Bell
Coleman cycle increases.

19. Results
 The Cooling effect of the Bell Coleman cycle is
found out to be 0.011 KW
 The COP of the Bell Coleman cycle is found out to
be 0.015

20. VORTEX TUBE
 The vortex tube is a structurally simple device with no moving parts that is
capable of separating a high-pressure flow into two lower pressure flows
with different energies, usually manifested as a difference in temperatures.
The vortex tube is relatively inefficient as a stand-alone cooling device but
it may become an important component of a refrigeration system when
employed as an alternative to the conventional throttling valve.

21. Vortex tube working principle

22. Vortex tube has following parts:
 Air Inlet
 Vortex Chamber
 Hot end side
 Cold end side
 Hot end obstruction
Construction details of Vortex tube

23. Air Inlet

24. Vortex Chamber
 Vortex chamber has nozzles for air to enter the
chamber and an orifice

25. Vortex chamber

26. Orifice and Venturi

27. Nozzles

28. Hot end obstruction

29. Standard Dimensions
 Tube Inner diameter = D
 Nozzle diameter = D/8
 Orifice diameter = D/2
 Cold end length = 10D
 Hot end length = 45D
We have varied these dimensions and fabricated four
different vortex tubes and observed the COP’s and
Cooling effects

30. Dimensions of fabricated Vortex
tubes
 Tube inner diameter (small) – 13.5mm (Tubes 1 & 2)
 Tube inner diameter (Big) – 19mm (Tubes 3 & 4)
 Couplings
 Cold end lengths - 135mm, 190mm (rounded off a bit)
 Hot end lengths - 608mm, 855mm (rounded off a bit)
 Orifice diameter - 6.75 (Tubes 1 & 2)
 Venturi diameter - D = 19mm , d = 9.5mm

32. Vortex Tube – 1 (2 Holes, Orifice)

33. Vortex Tube – 2 (4 Holes, orifice)

34. Vortex Tube – 3 (2 Holes, Orifice)

35. Vortex Tube – 4 (4 Holes, Venturi)

36. VORTEX TUBE: The experimental setup of vortex
tube air refrigeration system is same as Bell- Coleman
cycle. The only change is heat exchanger is removed
and vortex tube is added to the cycle
EXPERIMENTAL SETUP
Air
compressor
Heat
exchanger
Vortex tube Cabin

37. Vortex Tube Experimental set up

38. Digital thermometer

39. Digital Anemometer

40. Procedure of experiment
 For four different Vortex tubes which we fabricated, we
calculated Cooling effects and COP’s at different inlet
pressures.
 We also calculated mass flow rates and plotted graphs
for
1) Mass flow rates versus Temperature difference
2) COP versus Inlet pressures
and came at various conclusions.

41. Working Video

42. 0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
6 5 4 3 2
COP
Pressure
COP(1)
COP(2)
COP(3)
COP(4)
Temperature differences of 4 vortex tubes at
different pressures

43. COP of 4 vortex tubes at different
pressures
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
6 5 4 3 2
COP
Pressure
COP(1)
COP(2)
COP(3)
COP(4)

44. Observations
 After injecting the air at the different pressures, we
found out the max difference in the temperature of the
air at both the ends for our vortex tubes is around
35oC.
 This temperature difference is not noticeable or not as
expected from the vortex flow tube. As vortex flow
tubes generally give the difference around 70-80 0 C.
 It is observed that as the as the inlet air pressure of the
vortex tube increases, the cooling effect also increases

45. Conclusions
 From the calculations it is observed that for the same
power input, cooling effect produced and COP of the
vortex tube is high compared with cooling effect and
COP of Bell-Coleman cycle
 Of the 4 fabricated vortex tubes, Vortex tube 1
(internal diameter = 1.35 cm and 2 holes with orifice)
has higher COP and cooling effect than others.
 COP of vortex tube 1 is 0.03574 at 6 kg/cm2 inlet
pressure.

46. Comments
 One reason of our set up not giving temperature
difference of 70-80 oC is the air leakage. Some amount
of air was leaking from the compressor fittings,
coupling of the pipes.

47. Advantages of vortex flow tube
 1. It uses air as refrigerant, so there is no leakage problem.
 2. There are no moving parts in the vortex tube
 3. Vortex tube is simple in design and it avoids control
system.
 4. It is light in weight and requires less space.
 5. Initial cost is low and its working expenses are also less,
where compresses air is readily available.
 6. Maintenance is simple and no skilled labour are
required.
 7. Very simple design can easily be made at home.
 8. Can cool the fluid up to 4 0C.

48. Disadvantages
 1. Its low COP
 2. Limited capacity.
 3. Small portion of the compressed air appearing as the
cold air limits its wide use in practice.

49. Applications
 1. Vortex tubes are extremely small and as it produce
hot as well as cold air. It may be used in industries
where both are simultaneously required.
 2. Low temperatures can be obtained without any
difficulty, so it is very much useful in industries for
spot cooling of electronic components.
 3. It is commonly used for body cooling of the workers
in mines.

50. Future scope
 By using continuous discharge compressors (vane type or
gear type) we can get continuous and high air pressures.
Because of which high cooling effect and COP can be
achieved for both Bell-Coleman cycle and Vortex tube air
refrigeration system.
 By using high capacity Vortex tubes, high cooling rates by
Vortex tube air refrigeration system can be achieved.
 By sending the air at high pressure and low temperature
into Vortex tube, even low cold end temperatures can be
achieved.

51. References
Sl.n
o
Paper Author
1 Review on Vortex tube Refrigeration Rahul Dilip Pawar
N.C.Ghuge
2 The Application Of Vortex Tubes to
Refrigeration Cycles.
G. F. Nellis
S. A. Klein
3 Experimental Performance Study of
Vortex Tube Refrigeration System
Sankar Ram T
Anish Raj K
4 Performance Analysis of a Vortex Tube
by using Compressed Air
Ratnesh Sahu, Rohit Bhadoria,
Deepak Patel
5 An Experimental Setup of Vortex Tube
Refrigeration System
Karthik S

52. Sl no paper Author
6 Vortex tube refrigeration system
Based on Compressed air.
Tejshree Bornare,
Abhishek Badgujar,
Prathamesh Natu
7 Experimental Investigation of Vortex Tube
Refrigeration.
Sarath Sasi1, Sreejith
8 Experimental study of Bell Coleman cycle
using Air as Refrigerant
P.V.Ramana
9 Performance evaluation of refrigeration
system based on Bell coleman
Cycle
Rahul Patel
Ramji Tripathi

53.  Otto Belden blog on Construction of vortex tube
 Various youtube videos
 various articles about vortex tube on google
 Wikipedia

54. THANK YOU 