Tables for refrigerant of R134a in the domestic refrigerator

✅ Paper Type: Free Essay	✅ Subject: Education
✅ Wordcount: 3329 words	✅ Published: 13th Oct 2016

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CHAPTER -4

RESULTS & DISCUSSION

4.1 Experimental Procedure on Running Refrigeration Tutor

4.1.1 Tables for refrigerant of R134a in the domestic refrigerator

Table reading taken from the process of R134a refrigerant placed within the experimental setup. Note the reading of compressor water, mechanical device outlet condenser outlet, evaporator temperature pressure & of varied parameters within the setup. This is the normal domestic refrigerator having refrigerant 180 grams placed in the system.

Table 4.1.1 Reading of R134a Refrigerant without Heat Exchanger

Operating freezer point

Time taken for 5 revolution

T₁

⁰c

T₂

⁰c

T₃

⁰c

P₁

(bar)

P₂

(bar)

P₃

(bar)

61:07

61:12

60:00

59:00

-3.7

-5.9

-9.3

-11

56.9

57.5

0.68

0.62

0.55

9.6

10.34

11.72

9.31

9.65

11.03

This is the heat exchanger domestic refrigerator having refrigerant 150 grams placed in the system, experimental setup is same & procedure is same as normal domestic refrigerator.

Table 4.1.2 Reading of R134a Refrigerant with Heat Exchanger

Operating freezer point

Time taken for 5 revolution

T₁

⁰c

T₂

⁰c

T₃

⁰c

P₁

(bar)

P₂

(bar)

P₃

(bar)

46:10

49:18

50:30

49:29

51:20

53:12

-7.9

-9.6

-12

-15

-17.8

54.8

54.9

55.6

58.5

59.2

44.3

42.3

41.6

42.6

43.1

0.68

0.55

0.58

0.37

0.344

17.24

15.51

15.72

15.86

15.17

16.55

14.62

15.03

15.17

14.48

4.1.2 Tables for refrigerant of R410a in the domestic refrigerator

Table 4.1.2.1 Reading for R410a without Heat Exchanger

Table reading taken from the experimental procedure of R410a refrigerant placed in the experimental setup

Operating freezer point

Time taken for 5 revolution

T₁

⁰c

T₂

⁰c

T₃

⁰c

P₁

(bar)

P₂

(bar)

P₃

(bar)

38:12

37:59

38:90

39:10

39:38

37:59

37:34

-10

-10.6

-12

-14.1

-16.8

-18.7

-19.6

55.9

57.4

56.8

57.2

58.4

59.3

45.2

45.1

43.9

43.8

44.3

1.24

1.103

1.17

1.24

30.6

31.37

31.72

29.65

30.34

. Note down reading as per procedure placed in third chapter-3

This is the normal domestic refrigerator having refrigerant 120 grams placed in the system

Table 4.1.2.2 Reading for R410a Refrigerant with Heat Exchanger

Operating freezer point

Time taken for 5 revolution

T₁

⁰c

T₂

⁰c

T₃

⁰c

P₁

(bar)

P₂

(bar)

P₃

(bar)

39:18

37:05

36:10

35:99

37:10

-10

-11.5

-13.7

-15

-16.3

-18.4

50.7

51.7

52.3

53.1

52.9

52.3

52.7

41.9

42.4

42.6

42.8

42.1

42.2

1.03

1.24

1.103

1.172

1.103

29.3

30.34

30.68

28.96

29.65

30.00

30.34

30.55

30.34

This is the heat exchanger domestic refrigerator having refrigerant 105 grams placed in the system. Experimental setup is same & procedure is same as normal domestic refrigerator.

4.2 Calculation the Coefficient of Performance a Refrigerator Tutor

4.2.1 Calculating COP of R134a Normal & Heat Exchanger Domestic Refrigerator

Sample Calculation for R134a Normal Refrigerator:

Taking valves from table 4.1.1 of following parameter

Evaporator temperature :T₁ ⁰c:-9.3

Pressure (bar) : P₁:0.55

Compressor temperature (outlet): T₂ ⁰c:57.5

Pressure (bar): P2:11.72

Condenser temperature (outlet):T₃ ⁰c:44

Pressure (bar): P₃:11.03

Taking reading and seeing enthalpy values from the data handbook with having refrigerant R134a PH chart

Evaporator enthalpy H₁:585KJ/Kg K

Compressor enthalpy H₂:615KJ/Kg K

Condensed enthalpy H₃:460KJ/Kg K

C.O.P :(H₁-H₃)/(H₂-H₁)

:(585-460)/ (615-585)

C.O.P:4.16

Sample Calculation for R134a with Heat Exchanger Refrigerator:

Taking valves from table 4.1.2 of following parameter

Evaporator temperature :T₁ ⁰c:-9.6

Pressure (bar) : P₁:0.58

Compressor temperature (outlet): T₂ ⁰c:55.6

Pressure (bar): P₂:15.72

Condenser temperature (outlet):T₃ ⁰c:41.6

Pressure (bar): P₃:15.03

Taking reading and seeing enthalpy values from the data handbook with having refrigerant R134a PH chart

Evaporator enthalpy H₁:587KJ/Kg K

Compressor enthalpy H₂:617KJ/Kg K

Condensed enthalpy H₃:458KJ/Kg K

C.O.P :(H₁-H₃)/ (H₂-H₁)

:(587-458)/ (617-587)

C.O.P:4.3

Refrigerating point

-9.5

-13.5

-17.5 for H.E

R134a without

Heat Exchanger

4.16

3.81

3.5

R134a with

Heat Exchanger

4.3

3.87

3.64

Table 4.2.1 C.O.P of R134a refrigerant with &without H.E

Figure 4.2.1 Graph Shows C.O.P of R134a refrigerant with & without H.E

4.2.2 Calculating COP of R1410a Normal & Heat Exchanger Domestic Refrigerator

Sample Calculation for R410a Normal Refrigerator:

Taking valves from table 4.1.2.1 of following parameter

Evaporator temperature :T₁ ⁰c:-12

Pressure (bar) : P₁:1.103

Compressor temperature (outlet): T₂ ⁰c:56.8

Pressure (bar): P₂:30

Condenser temperature (outlet):T₃ ⁰c:43.9

Pressure (bar): P₃:29.65

Taking reading and seeing enthalpy values from the data handbook with having refrigerant R410a PH chart

Evaporator enthalpy H₁:434.6KJ/Kg K

Compressor enthalpy H₂:441KJ/Kg K

Condensed enthalpy H₃:423KJ/Kg K

C.O.P :(H₁-H₃)/ (H₂-H₁)

:(434.6-423)/ (441-434.6)

C.O.P:1.81

Sample Calculation for R410a with Heat Exchanger Refrigerator:

Taking valves from table 4.1.2.2 of following parameter

Evaporator temperature :T₁ ⁰c:-11.5

Pressure (bar) : P₁:1.24

Compressor temperature (outlet): T₂ ⁰c:52.3

Pressure (bar): P₂:30.34

Condenser temperature (outlet):T₃ ⁰c:42.6

Pressure (bar): P₃:30.00

Taking reading and seeing enthalpy values from the data handbook with having refrigerant R410a PH chart

Evaporator enthalpy H₁:414.9KJ/Kg K

Compressor enthalpy H₂:425.4KJ/Kg K

Condensed enthalpy H₃:436.4KJ/Kg K

C.O.P :(H₁-H₃)/ (H₂-H₁)

:(414.9-436.4)/ (414.9-425.4)

C.O.P:2.047

Table 4.2.2 Represent C.O.P of R410a without & With H.E

Coefficient of performance (COP)
R410a without heat exchanger	2.33	1.81	1.42	1.7	1.58
R410a heat exchanger	3.57	2.04	1.74	1.83	1.92

Figure 4.2.2 Graph Shows COP Of R410a without & With H.E

4.3 Comparison of Discharge Temperature of R134 & R410a Refrigerant

4.3.1 Comparison of Discharge Temperature of R134a without & With H.E:

Following table show difference between normal & heat exchanger refrigeration tutor working of compressor discharge temperature thus shows the by using heat exchanger there is decrease in temperature . This leads to improve the performance of system compared to normal refrigerator tutor

Table 4.3.1 Shows Compressor Discharge Temperature of Normal & H.E Tutor

SNO	EVAPORATURE TEMPERATURE OF R134a	DISCHARGE TEMPERATURE O_C
1 2 3 4	Normal R.F	With H.E	Normal R.F	With H.E
-3.7 -5.9 -9 -11.1	-7.9 -9.6 -15 -19	55.6 56.8 57 62	54.8 55.6 58.5 60.1

Figure 4.3.1 Graph Shows Compressor Discharge Temperature Difference

4.3.2 Comparison of Discharge Temperature of R410a without & With H.E:

Table 4.3.2 Shows Compressor Discharge Temperature of Normal & H.E System

SNO	EVAPORATURE TEMPERATURE OF R410a	DISCHARGE TEMPERATURE ⁰c
1 2 3 4 5	Normal R.F	With H.E	Normal R.F	With H.E
-10 -12 -14 -16.8 -19.6	-10 -11.2 -15 -18 -19	55.9 56.8 57.2 58.4 60	50.7 52.3 52.9 53.5 52.7

Figure 4.3.2 Graph Shows Compressor Discharge Temperature Difference

4.4 Comparison of Refrigerator Tutor Running Time by Using Various Refrigerants in the System

4.4.1 Comparing Running Time Consumption R134a Refrigerator Tutor Without & With H.E:

When running of refrigerator tutor time calculates to get final refrigeration effect in the evaporator, when staring from end of cut-off time is taken by the refrigerator tutor.

Table 4.4.1 Time Taken for Running R134a Refrigerator Tutor without & with H.E

SNO

EVAPORATOR TEMPERATURE POINT R134a

TIME TAKEN GRADUALLY MINUTES

Normal R.F

12.2

1.3

-3.7

-5.9

-7.7

-9

With H.E

-10

-17.9

-20.1

-20.8

Normal R.F

With H.E

In this process found that time is decreased when tin the H.E refrigerator running time compared to normal refrigerator without H.E.

Figure 4.4.1 Graph Shows Difference of Time Taken for Running Refrigeration system

4.4.2 Comparing Running Time Consumption R410a Refrigerator Tutor Without & With H.E:

When the running mode of refrigerator tutor time calculate to get final refrigeration effect in the evaporator, when staring from end of cut-off time is taken by the refrigerator tutor .In this process found that time is decreased when tin the H.E refrigerator running time compared to normal refrigerator without H.E.

Table 4.4.2 Time Taken for Running R410a Refrigerator without & with H.E

SNO	EVAPORATOR TEMPERATURE R410a	TIME TAKEN GRADUALLY MINUTES
1 2 3 4	Normal R.F	With H.E	Normal R.F	With H.E
-6.9 -14.6 -16.9 -20.1	0.9 -10.7 -16.4 -20.5	20 50 60 80	10 20 30 47

Figure No 4.4.2 Shows Difference of Time Taken For Running Refrigeration

4.5 Calculating Energy Consumption of Various Refrigerant using without & with H.E

4.5.1 Calculating the Energy Consumption for the Domestic Refrigerator for Running System:

By giving electric power to refrigerator tutor energy meter placed to output supply to calculate energy consumption .Taking the reading from table 4.1.1&4.1.2 evaporator, 5 revolution of energy meter in seconds. Hence calculate the energy consumption into hours.

At -9ºc freezer point time taken for 5 revolution of energy meter is 60second

Energy meter constant :1200revolution: 1 KW

:1200=3600Kj

1 revolution:3600/1200 Kj/rev

For 5 revolution :(5*3600)/ (60*1200)

Energy consumption: 0.25Kw-hr

Table 4.5.1 Reading of Energy Consumption (KW) of Domestic Refrigerator during operation

Freezer cut-off point O_C

-3.7

-5.9

-9

-11.1

R134a

Without H.E

0.2456

0.245

0.25

0.254

R134a

With H.E

0.325

0.298

0.292

0.288

Figure 4.5.1 Shows the Difference of Energy Consumption in Without & With H.E

4.5.2 Calculating the Energy Consumption for the Domestic Refrigerator for Running System:

By giving electric power to refrigerator tutor energy meter placed to output supply to calculate energy consumption .Taking the reading from table 4.1.2.1 & 4.1.2.2 evaporator, 5 revolution of energy meter in seconds. Hence calculate the energy consumption into hours.

At -10ºc freezer point time taken for 5 revolution of energy meter is 38.12second

Energy meter constant :1200revolution: 1 KW

:1200=3600KJ

1 revolution:3600/1200 KJ/rev

For 5 revolution :(5*3600)/ (38.12*1200)

Energy consumption: 0.393kw-hr

Table 4.5.2 Reading of Energy Consumption (kw) of Domestic Refrigerator during Operation

Freezer cut-off point O_C

-10

-12

-14.1

-16.8