Thermodynamic Analysis of Eco-Friendly Refrigerant Mixtures as an Alternative to HFC-134a in Household Refrigerator

Thermodynamic Analysis of Eco-Friendly Refrigerant Mixtures as an Alternative to HFC-134a in Household Refrigerator

Mohammad Hasheer Shaik* Srinivas Kolla Tara Chand Vadlamudi Bala Prasad Katuru Ravindra Kommineni

Department of Mechanical Engineering, R.V.R. & J.C. College of Engineering (A), Guntur, Andhra Pradesh 522019, India

Corresponding Author Email: 
hasheer.mohammad@gmail.com
Page: 
1567-1574
|
DOI: 
https://doi.org/10.18280/ijht.390519
Received: 
26 August 2019
|
Accepted: 
2 July 2021
|
Published: 
31 October 2021
| Citation

OPEN ACCESS

Abstract: 

Nowadays, research has been focused on refrigerants from Hydrofluorocarbons (HFCs), which are not harmful to the ozone layer. Because of replacing refrigerants from chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs). HFCs are used in many applications, including refrigerants, aerosols, solvents, and blowing agents for insulating foams. However, some HFCs have relatively high global warming potential (GWP) and are subject to further examination due to growing concerns about global climate change. The present work’s main objective is to select eco-friendly refrigerants from AC5, R430A and R440A, combining two or more refrigerants from HC, HFC and HFO groups as a direct substitute HFC-134a in a household refrigerator. The performance of the domestic refrigerator with liquid suction heat exchanger (LSHX) was compared in terms of compressor discharge temperature, coefficient of performance (COP), volumetric cooling capacity (VCC), and power consumption of a compressor. It was found that the average COP of R440A and R430A was higher by approximately 2.5% and 1.47% than HFC-134a. However, the COP of AC5 was 6.1% lower than that of HFC-134a. The VCC of R430A is almost equal to HFC-134a. The results also show that AC5, R440A and R430A consume less power than HFC-134a. The compressor outlet temperature with R440A, AC5 provide higher values than HFC-134a, which affects the compressor life. The best overall performance was achieved with the refrigerant R430A in the household refrigerator and suggested an alternative to HFC134a, which also has a very low GWP from the environmental safety perspective.

Keywords: 

eco-friendly refrigerants-AC5, R440A and R430A, household refrigerator, liquid suction heat exchanger

1. Introduction

Environmental pollution is aggravated by the excessive use of refrigerators and air conditioners worldwide, along with automobiles. The ozone layer is damaged by releasing refrigerants containing chlorine into the atmosphere. Due to this, dangerous ultraviolet radiations are coming to the surface of the earth. As a result, the earth’s surface temperature is increasing rapidly, leading to weather change. The effect of these greenhouse gases can be expressed in terms of GWP. In the last 30 years, CFCs and HFCs are widely used in refrigerators and air conditioners. However, ODP and GWP values are very high for these refrigerants, which cause environmental pollution. According to Montreal protocol, chlorofluorocarbons and HCFC are entirely prohibited in the air conditioning and refrigeration sector due to this higher ODP value. Therefore, in place of these refrigerants, HFC refrigerants are introduced, but the main problem with these refrigerants is that they have a higher GWP value. Therefore, these should be banned in the coming years based on the Kyoto Protocol. Therefore, R134a has to be phased out by 2021. In addition, most of the developing countries are drastically reducing their HFC production and consumption. Therefore, there is a greater demand for an adequate replacement for HFC-134a to adapt to existing and new systems.

Hoe et al. [1] experimented with R600a, which is a substitute to the R12 in a household refrigerator. They analyzed theoretically with the help of software REFPROP, and then performed a series of tests with this refrigerant substitute to R134a in a fridge. Jung et al. [2] conducted an experiment with a mixture of HC290 / HC600a (60:40 by mass) as a direct substitute for R12 in a refrigerator and concluded that COP and power efficiency improved by 2.5 and 3.8%. Fatouh and Kafafy [3] studied the performance of the household refrigerator that works with the refrigerant mixture (consist of HC290 / HC600 / HC600a in the ratio 60:20:20 by mass) a substitute to HFC-134a. It has been reported that the power consumption of compressor operating with an LPG blend was 5.1% lower than HFC-134a with 7.5% higher COP. Garland and Hadfield [4] studied the environmental impact of the R600a natural refrigerant installed in the hermetic compressor of the household refrigerator. The results showed that the R600a is superior to the R134a, with the compressor having its 15-year cycle.

Dalkilic and Wongwises [5] conducted a theoretical analysis on the refrigerator using various alternative refrigerants and refrigerant mixtures as an alternative to R12 and R22. They concluded that HFC and HC refrigerants could be used as alternatives to the above refrigerants from that theoretical analysis. Naushad et al. [6] had conducted an energy and exergy analysis of R1234yf, R1234ze (E) and R134a in a domestic refrigeration system. Finally, they concluded that HFO-1234yf could be used as a good substitute for HFC-134a at a higher value of the evaporator temperature, and R1234ze (E) can be used as a suitable replacement after specific modification. Rastietal [7] conducted an experiment on R600aand R436a consisting of 46% and 50% of isobutane and propane) as an alternative to R134a in a household refrigerator. The results concluded that the compressor energy consumption and volumetric cooling capacity was reduced by about 15% and 8%, respectively. Joybari et al. [8] carried out the exergy analysis to find the optimal load of HC-600a as a substitute for HFC-134a, the optimum load required for HC-600a was 0.050kgand 65% lower than HFC-134a. Bilen et al. [9] investigated theoretical analysis of the automobile air conditioning system using R152a, R22 and R12 to find out possible alternatives to R134a. From the results, they concluded that the performance does not change significantly by using R152a as compared with R134a. Bolaji et al. [10] made a performance comparison of low GWP refrigerants like R152a and HC600 theoretically, an alternative to HFC134a in a refrigerator. By observing these results, they concluded that R152a shows a higher volumetric cooling capacity (VCC) and co-efficient performance compared to HFC-134a. The average COPs achieved for HC-600a and HC-152a were 6% lower and 12.9% higher than HFC-134a. They concluded that HFC-152a shows the best results as compared with R134a. Morsi [11] performed a theoretical analysis of a VCR system using pure natural refrigerants to substitute HFC-134a. Results revealed that LPG gives a lower COP, and Isobutene gives a higher COP than HFC-134a by 11% and 5%, respectively.

Meng et al. [12] have done thermodynamic investigation for HFO-1234ze (E), R152a and HFO-1234ze (E)/R152a blends as a direct substitute to HFC-134a in a refrigerator system without making any modifications to the system. Sanchez et al. [13] led an experiment with low GWP refrigerants like HFO-1234yf, 1234ze (E), R290, R152a and HC-600a in the refrigeration system and experimental results were compared with HFC-134a. From that experiment, they concluded that HFO-1234yf and R152a have a perfect substitute for HFC-134a. Makhnatch et al. [14] examined the performance ofR450Awhich is a mixture of R134a/R1234ze (E) (42:58% by mass) as a substitute to HFC-134a in household refrigerators. It has been revealed that the Refrigerating effect and COP of the refrigerant mixture were approximately 10% and 3% lower than HFC-134a. At the same time, the outlet temperature of the compressor is more inferior to HFC-134a. Hasheer and Srinivas [15] conducted a theoretical investigation on low GWP refrigerants as a direct substitute to R134a in a domestic refrigerator. They concluded that R1234yf could be used as a natural substitute to R134a. Mohammad Hasheer Sk et al. [16] performed a thermodynamic analysis of low gwp refrigerant mixtures as alternative to R134a in refrigerator. From that they concluded that R290/600(60/40), ARM42, ARM42a, R440A, and R430A have better COP execution and volumetric cooling limit than R134a, which makes it the best substitute to R134a shows a favorable conditions.

A review of existing literature shows that much research has been done to find suitable alternative refrigerants from different groups individually. But the combination of two or more refrigerants from HC, HFC and HFO groups have not tried so far by the previous researchers. Also, the performance evaluation with LSHX was not done extensively. So the present work mainly focuses on filling that research gap. So the investigation was carried out with the refrigerants AC5, R440A and R430A. They are the combination of two or more refrigerants from the above-said groups. So the performance of a domestic refrigerator involving LSHX was evaluated with these three refrigerants, and the best alternative refrigerant to replace R134a have been identified and suggested.

2. Environmental Impact of Alternative Refrigerant Mixtures

Low GWP refrigerants can be categorized as pure Hydrofluorocarbons and Hydrofluoroolefins. Hydrofluoroolefins (HFO) is not new to chemistry. Like conventional Hydrofluorocarbons (HFCs), they are composed of hydrogen, fluorine and carbon. The only difference is that they are unsaturated, which means they have at least one double bond. Such molecules are called olefins or alkenes, so it is correct to name refrigerants such as HFC, HFA or HFO. The next name has become the most used name to refer to carbon-carbon double-bond refrigerants. Hydrofluoroolefins can be classified as HFO-1225, 1234 and 1243 isomers. Due to the flammability, the R1243 isomer is not used, and also, due to toxicity, the HFO-1225 isomer has not been developed. Therefore, the two possible alternatives in a household refrigeration system are HFO-1234yf and 1234ze (E). Another low GWP refrigerant is pure Hydrofluorocarbons, i.e. HFC152a, which has a very low GWP, value compared with HFC134a. HC (Hydrocarbons) are natural refrigerants that are R290 and R600a. These refrigerants have a GWP value of zero and exceptional properties in terms of efficiency and cooling effect.

The alternative refrigerants require not only protecting the ozone layer but also a lower GWP value. The low GWP refrigerants mixtures are R440A (R290/R134a/R152a in the ratio of 0.6:1.6:97.8 by mass, respectively), R430A (R152a/R600a 76:24in the ratio, by mass) and AC5 (R32/R152a/R1234ze (E) 12:5:83 in the ratio, by mass) were proposed in this document considered as substitutes for HFC-134a. The Thermo-physical and Environmental properties of above refrigerants are mentioned in the Table 1.

Table 1. Thermo-physical and Environmental properties of the refrigerants investigated

Properties

Refrigerants

R134a

AC5

R440A

R430A

 

Composition

 

-----

R32 (12%)

R152a (5%)

R1234ze (E) (83%)

R290 (0.6%)

R134a (1.6%)

R152a (97.8%)

R152a (76%)

R600a (24%)

Molar mass (kg/kmol)

102

96.7

66.23

63.96

Critical temperature (℃)

101.01

103.2

112.66

106.98

Boiling point, BP (0C)

- 26.1

-34.3 to -23.3

- 25.4

-27.6

Liquid density at 298 K (kg/m3)

1206.7

1101.2

897.62

759.78

Vapor densityat 298K (kg/m3)

32.35

28.92

18.68

19.69

ODP

0

0

0

0

GWP

1430

92

150

104

GWP value of the refrigerant mixtures can be calculated as follows:

GWPmixture = GWPp x Wp + GWPq x Wq +GWPr x Wr

where, GWPp=GWP value of refrigerants p, GWPq= GWP value of refrigerant q, GWPr= GWP value of refrigerant r respectively; Wp, Wq and Wr are to be mass fraction of refrigerants p, q and r.

3. Thermodynamic Analysis of Refrigerant Mixtures

The thermodynamic Analysis of AC5, R440A and R430Aas a direct substitute to HFC-134a in a refrigeration system by varying the working conditions, i.e. when changing the temperature of the evaporator from -200℃ to 100℃ at different condenser temperatures. The complete analysis has been carried out by using an internal heat exchanger.

Figure 1. Refrigerator with LSHX

Figure 2. Pressure-enthalpy diagram of a refrigerator with LSHX

Data (from the literature review) used for analysis are given below. The results are plotted as shown in Figures 3 to 8.

1. Condensing temperatures: 40℃ and 50℃ 

2. Evaporating temperatures: -20℃ to 10℃

3. Loss of Pressure in the evaporator: 0.03 MPa

4. Loss of Pressure in the condenser: 0.02 MPa

5. Isentropic efficiency of a compressor: 0.70

6. Volumetric efficiency: 0.75

7. Compressor had a swept volume: 8.16cm3/rev

8. Compressor Speed: 30rev/sec

9. Effectiveness of the heat exchanger: 0.6.

The components of a domestic refrigerator with LSHX in the position shown in Figure 1. The pressure-enthalpy diagram with the heat exchanger is shown in Figure 2. At the entry to the compressor, the refrigerant is in superheated condition, and pressure losses are considered. At the same time, it passes through the evaporator and condenser and is also represented in Figure 2. REFPROP 9.1 software is used to calculate the properties at each state, which is very accurate software for calculating properties.

Pressure ratio, volumetric cooling capacity, COP, outlet compressor temperature, Refrigeration effect and compressor power consumption is the main parameters to accept a direct substitute to a domestic refrigerator.

3.1 Performance parameters

The pressure ratio can be expressed as

$r_{p}=P_{\text {cond }} / P_{\text {evap_act }}$               (1)

Compressor power consumption can be calculated from

$\dot{\mathrm{W}}_{\text {comp }} \quad \dot{\mathrm{m}}_{\mathrm{r}}\left(\mathrm{h}_{2}-\mathrm{h}_{1}\right) \mathrm{kW}$               (2)

Here $h_{1} \& h_{2}$ are the enthalpies of the refrigerant at entry and exit of the compressor. The relation between these two can be obtained by defining isentropic efficiency $\left(\eta_{\text {isen }}\right)$ of the compressor as follows

Where $h_{2}=h_{1}+\left(h_{2 s}-h_{1}\right) / \eta_{\text {isen }}$                    (3)

The refrigeration effect of a refrigerator can be calculated by

Refrigeration effect, $Q_{r}=\left(h_{1}-h_{5}\right) \quad \mathrm{kJ} / \mathrm{kg}$          (4)

Here $h_{5}$ is the enthalpy of the refrigerant at the entry to the evaporator.

The cooling capacity of a refrigerator can be calculated by

Cooling Capacity, $\dot{Q}_{c}=\dot{m}_{r} Q_{r}=\dot{m}_{r}\left(h_{1}-\right.\left.h_{5}\right) \mathrm{kW}$             (5)

The Coefficient of Performance (COP) of the refrigerator is given by

COP $=\frac{\text { Cooling capacity }}{\text { Compressor power consumption}}\quad=\frac{\dot{m}_{r}\left(h_{1}-h_{5}\right)}{\dot{m}_{r}\left(h_{2}-h_{1}\right)}=\frac{\left(h_{1}-h_{5}\right)}{\left(h_{2}-h_{1}\right)}$               (6)

The Volumetric Cooling Capacity (VCC) is given by 

$Q_{\text {vol }}=\left(h_{1}-h_{5}\right) \times \eta_{\text {vol }} / v_{1} \mathrm{~kJ} /$             (7)

Here $\eta_{\text {vol }}$ is the volumetric efficiency of the compressor and $v_{1}$ is the specific volume of the refrigerant at the compressor inlet.

The mass flow rate of the refrigerant ( $\dot{m}_{r}$ ) is given by

$\dot{m}_{r}=V_{\mathrm{c}} \times \rho_{1} \times R P M \times \eta_{\text {vol }} / 60 \mathrm{~kg} / \mathrm{s}$                (8)

4. Results and Discussion

In the present work the performance of domestic refrigerator incorporated with LSHX was tested with different refrigerants AC5, R440A and R430A at two condenser temperatures of 40℃ and 50℃ with varying evaporator temperature from -20℃ to 10℃. The results obtained from the theoretical analysis were mentioned in the Appendix and the important performance plots are drawn and discussed as below.

4.1 Variation of the mass flow rate of alternative refrigerants

Figure 3 depicts the mass flow rate of four refrigerants versus the temperature of the evaporator. Mass flow rate is the mass of refrigerant which pass per unit time. Mass flow rate is directly proportional to vapour density. Mass flow rate changes with change in evaporator temperature and do not vary with condenser temperature. For AC5, the mass flow rate is lower than R134a by 8.59% within an evaporator temperature range of -20℃ to 10℃, respectively. For R440a, the mass flow rate is lower than HFC-134a by 30.18% within an evaporator temperature range of -20℃ to 10℃, respectively. For R430a, the mass flow rate is lower than HFC-134a by 25.75% within an evaporator temperature range of -20℃ to 10℃, respectively, due to low vapour density. Hence we can expect low power consumption with the above refrigerants as compared to R134a.

Figure 3. Refrigerant Mass flow rate (Kg/s) vs. Evaporator temperature (℃)

4.2 Pressure ratio variation

Figure 4. Pressure ratio vs Evaporator temperature (℃)

Figure 4 shows the graph between pressure ratios versus evaporator temperature. Pressure ratio is a ratio of higher pressure to lower pressure in VCR (vapour compression system). The pressure ratio is directly proportional to condenser temperature and inversely proportional to evaporator temperature. The results show that the pressure ratio of AC5 was higher than that of HFC-134a by approximately 1.13%, 1.48%, and 1.88%. At the same time, the pressure ratio of R440A and R430A lower than that of R134a by about 1.19%, 5.78%, respectively. Compressor volumetric efficiency compressor is influenced by pressure ratio. It is inversely proportional to volumetric efficiency, so from the above results, we observed that R440A and R430A have some percentage drop in pressure ratio compared to R134a. So we can expect excellent volumetric efficiency with these refrigerants.

4.3 Variation of volumetric cooling capacity

Figure 5 describes the deviation of VCC concerning the evaporator temperature for four different refrigerants. At a condenser temperature of 40℃ and 50℃, it was obtained that the VCC of AC5 is lower than R134a by 9.91%, 10.10% and 10.35%, respectively, within an evaporator temperature range of -20℃ to 10℃, respectively. VCC of R440A is lower than R134a by 6.4%, 5.1%, and 3.4%, respectively, within an evaporator temperature range of -20℃ to 10℃. At 40℃ and 50℃ of condenser temperatures, R430a has a VCC lower than R134a by 1.12%, 0.41%, and higher by 0.44%, respectively, within an evaporator temperature range 20℃ and 10℃. The capacity of volumetric cooling has a more significant influence on the size of the compressor. For replacement refrigerants, VCC can be maintained with a limit between -8% and 8% about HFC-134a. Due to a lower volumetric cooling capacity, AC5 Refrigerant is not advisable as it affects the compressor performance. Therefore, this refrigerant cannot be replaced as an alternative to HFC-134a. Consequently, considering that refrigerants R440A, R430A are suggested as a direct replacement of HFC-134a without alterations in the compressor.

Figure 5. VCC vs Evaporator temperature (℃)

4.4 Variation of compressor power

The variation of compressor power versus evaporator temperature is shown in Figure 6. The average compressor power consumption of refrigerants AC5, R440a, R430a was lower than that of HFC-134a by about 4.1%, 7.6% and 1.4% respectively at condenser temperatures 40°C & 50°C. The energy consumption of a refrigerator compressor increases with the evaporator temperature due to the increase in the enthalpy difference between the output and the compressor inlet. This difference in enthalpy is due to the rise in the mass flow rate of the refrigerant.

Figure 6. Compressor work (W) vs Evaporator temperature (℃)

4.5 Variation of COP

Figure 7 represents the deviation of COP of alternative refrigerants versus evaporator temperature. It was obtained that the average COP of R440A, R430A was higher than HFC-134a by approximately 1.37%, 2.7% at a condenser temperature 40C and higher than that of R134a 2.5%, 3.2%, respectively at a condenser temperature of 50℃. This is due to the lower power consumption of a refrigerator compressor. On the other hand, AC5 has a lower cop than R134a by approximately 6.58%, 5.6% at a condenser temperature of 40℃ and 50℃.

Figure 7. COP vs. Evaporator temperature (℃)

4.6 Variation of outlet temperature of compressor

The outlet temperature of the reciprocating refrigerant compressor versus evaporator temperature is shown in Figure 8 below. It was found that the average discharge temperature of compressor AC5, R440A and R430A was higher than that of HFC-134a of approximately 6-10°C, 3-7°C and 2-6°C at condenser temperatures of 40℃ & 50℃. The higher outlet temperature affects the compressor motor coil and also affect the lubricant oil properties. Therefore, care must be taken when using this refrigerant as a direct substitute to HFC-134a in a refrigerator.

Figure 8. Compressor outlet temperature (K) vs. Evaporator temperature (℃)

5. Conclusions

The AC5 refrigerant shows a much lower volumetric cooling capacity compared to HFC-134a of approximately 9.1%. For a direct replacement, the value must be between -8% and 8%. Therefore, it is not suitable for direct use as a substitute for HFC-134a in a household refrigerator. R440A and R430A had given good results in VCC, power consumption of a compressor, COP and pressure ratio. But R440A shows a high compressor output temperature that affects the properties of lubricating oil for refrigerator compressor. When comparing all results with R134a, R430A can be used as a direct substitute for HFC-134a in the household refrigerator without changing the refrigerator. Therefore, it is concluded that R430A can be used as an alternative to HFC-134a in a household refrigerator. At the same time, when comparing the results with the literature (without LSHX) there is an improvement in the performance of a household refrigerator.

Nomenclature

COP

Coefficient of performance

GWP

Global warming potential

h

Specific enthalpy (kJ/kg)

LSHX

Liquid –suction heat exchanger

$\dot{m}$

Mass flow rate (kg/s)

Qvol

Volumetric Cooling Capacity (kJ/m3)

$\dot{Q}_{c}$

Cooling capacity (kW)

Q r

Refrigeration effect (kJ/kg)

R

Refrigerant

rp

pressure ratio

v

Specific volume (m3/kg)

Vs

Compressor displacement (m3/rev)

$\dot{W}_{\text {Comp }}$

Compressor power consumption (kW)

Greek symbols

$\eta$

Efficiency (%)

$\rho$

Density (kg/m3)

Subscripts

1, 2, 3,4,5,6

state points

Comp

compressor

Cond

condenser

evap_act

actual evaporator

isen

isentropic

Lshx

liquid suction heat exchanger

r

refrigerant

vol

volumetric

Acronym

CFC

Chlorofluorocarbons

HC

Hydrocarbons

HCFC

Hydrochlorofluorocarbons

HFC

Hydrofluorocarbons

HFO

Hydrofluoroolefins

RPM

Revolutions per minute

Appendix

Theoretical results of different refrigerants investigated

CONDENSER TEMP =20℃

Evaporator Temp (℃)

Parameter

R134a

AC5

R440a

R430a

-20

COP

2.723

2.5521

2.7922

2.7582

 

T2

330.065

331.480

347.223

336.074

 

Pr

7.2566

7.3811

7.1322

6.6142

 

RE

163.995

146.565

158.465

169.485

 

W

60.2248

57.4273

56.7522

61.4463

 

mr

0.00107

0.00095

0.00063

0.00071

 

Qvol

669.914

598.716

647.328

692.343

-10

COP

3.625

3.4029

3.6927

3.6619

 

T2

324.551

325.613

337.831

329.122

 

Pr

4.7068

4.7726

4.6501

4.3807

 

RE

257.224

230.958

244.255

259.090

 

W

70.9565

67.8699

66.144

70.7525

 

mr

0.00161

0.00144

0.00095

0.00105

 

Qvol

1050.75

943.456

997.774

1058.37

0

COP

6.129

5.7709

6.1894

6.1697

 

T2

317.8262

318.4168

326.0162

320.5626

 

Pr

2.6333

2.6578

2.6164

2.5197

 

RE

474.2585

428.4571

439.8774

461.4826

 

W

77.3791

74.2438

71.0685

74.7971

 

mr

0.00281

0.002516

0.001646

0.001781

 

Qvol

1937.33

1750.233

1796.885

1885.141

10

COP

13.7203

12.941

13.7439

13.7623

 

T2

312.4305

312.6931

316.2469

313.6699

 

Pr

1.5778

1.5853

1.57375

1.546

 

RE

822.2744

746.8862

746.5463

776.1278

 

W

59.9311

57.71468

54.3182

56.395

 

mr

0.004631

0.004154

0.00269

0.002862

 

Qvol

3358.964

3051.006

3049.617

3170.457

CONDENSER TEMP=40℃

Evaporator Temp (℃)

Parameter

R134a

AC5

R440a

R430a

-20

COP

2.1509

2.007329

2.2407

2.1958

 

T2

341.38

343.0975

360.4962

348.0223

 

Pr

9.5808

9.7791

9.4043

8.6289

 

RE

148.5438

132.3568

146.8354

155.2198

 

W

69.05949

65.9367

65.5297

70.6885

 

mr

0.001071

0.000954

0.000637

0.000713

 

Qvol

606.7968

540.6732

599.8181

634.0681

-10

COP

2.7832

2.602066

2.8737

2.8298

 

T2

336.1375

337.4736

351.4524

341.3648

 

Pr

6.2143

6.32313

6.1314

5.7151

 

RE

233.9562

209.5158

226.8553

238.0492

 

W

84.0598

80.519

78.9397

84.1203

 

mr

0.001613

0.00144

0.000953

0.001052

 

Qvol

955.7038

855.8653

926.6964

972.4235

0

COP

4.3449

4.0743

4.4332

4.3937

 

T2

329.7558

330.5883

340.0767

333.1769

 

Pr

3.4767

3.52137

3.4499

3.2872

 

RE

433.7212

391.0004

409.8254

425.8386

 

W

99.822

95.9665

92.4435

96.9192

 

mr

0.00281

0.002516

0.001646

0.001781

 

Qvol

1771.737

1597.224

1674.124

1739.537

10

COP

7.8321

7.3536

7.9006

7.8727

 

T2

324.648

325.1269

330.6743

326.595

 

Pr

2.0832

2.1004

2.075

2.0169

 

RE

755.4909

685.0454

697.4433

718.862

 

W

96.46

93.15769

88.2767

91.3104

 

mr

0.004631

0.004154

0.00269

0.002862

 

Qvol

3086.156

2798.388

2849.033

2936.528

CONDENSER TEMP=50℃

Evaporator Temp (℃)

Parameter

R134a

AC5

R440a

R430a

-20

COP

1.7149

1.5916

1.8266

1.7702

 

T2

352.0495

354.1167

372.6777

359.1741

 

Pr

12.4233

12.7302

12.1808

11.0684

 

RE

132.6201

117.6973

134.8612

140.4975

 

W

77.3331

73.948

73.8288

79.3646

 

mr

0.001071

0.000954

0.000637

0.000713

 

Qvol

541.749

480.7898

550.9037

573.9278

-10

COP

2.1799

2.02766

2.2951

2.238

 

T2

347.1343

348.7888

364.0624

352.8692

 

Pr

8.058

8.2313

7.9417

7.3309

 

RE

209.977

187.3936

208.9412

216.3344

 

W

96.321

92.4182

91.034

96.6602

 

mr

0.001613

0.00144

0.000953

0.001051

 

Qvol

857.7492

765.4971

853.518

883.7192

0

COP

3.2445

3.02757

3.3638

3.3068

 

T2

341.162

342.2775

353.226

345.1232

 

Pr

4.5082

4.584

4.4685

4.2165

 

RE

391.9443

352.356

378.8852

389.0541

 

W

120.8016

116.3821

112.6342

117.6506

 

mr

0.00281

0.002516

0.001646

0.001781

 

Qvol

1601.08

1439.363

1547.734

1589.274

10

COP

5.2585

4.9131

5.3759

5.3205

 

T2

336.3926

337.1259

344.271

338.9059

 

Pr

2.7012

2.7342

2.6877

2.5872

 

RE

686.6651

621.2437

646.889

659.7641

 

W

130.5816

126.4446

120.3311

124.0035

 

mr

0.004631

0.004154

0.00269

0.002862

 

Qvol

2805.005

2537.76

2642.521

2695.115

  References

[1] Bolaji, B.O. (2014). Theoretical analysis of the energy performance of three low global warming potential hydro-fluorocarbon refrigerants as R134a alternatives in refrigeration systems. Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy, 228(1): 56-63. https://doi.org/10.1177%2F0957650913507252

[2] Jung, D., Chong-Bo, K., Kilhong, S., Byoungjin, P. (2000). Testing of propane/Isobutene mixture in domestic refrigerators. International Journal of Refrigeration, 23: 517-527. https://doi.org/10.1016/S0140-7007(99)00084-5

[3] Fatouh, M., Kafafy, M.E. (2006). Experimental evaluation of a refrigerator working with LPG. Applied Thermal Engineering, 26: 1593-1603. https://doi.org/10.1016/j.applthermaleng.2005.11.026

[4] Garland, N.P., Hadfield, M. (2005). Environmental implications of hydrocarbon refrigerants applied to hermetic compressor. Material and Design Journal, 26(7): 578-586. https://doi.org/10.1016/j.matdes.2004.08.009

[5] Dalkilic, A.S., Wongwises, S. (2010). A performance comparison of vapour compression refrigeration system using various alternative refrigerants. International Communication in Heat and Mass Transfer, 37(9): 1340-1349. https://doi.org/10.1016/j.icheatmasstransfer.2010.07.006

[6] Naushad, A.A., Yadav, B., Kumar, J. (2013). Theoretical Exergy analysis of HFP-1234yf and HFO-1234ze as an alternative replacement of HFC134a in simple vapour compression refrigeration system. International Journal of Scientific & Engineering Research, 4(8): 2229-5518. 

[7] Rasti, M., Aghamiri, S.F., Hatamipour, M.S. (2013). Energy efficiency enhancement of a domestic refrigerator using R436A and R600a as alternative refrigerants to R134a. International Journal of Thermal Sciences, 74: 86-94. https://doi.org/10.1016/j.ijthermalsci.2013.07.009  

[8] Joybari, M.M., Hatamipour, M.S., Rahimin, A. (2013). Exergy analysis and optimization of R600a as a replacement of R134a in a domestic refrigeration system. International Journal of refrigeration, 36(4): 1233-1242. 2013. https://doi.org/10.1016/j.ijrefrig.2013.02.012

[9] Bilen, K., Kalkisim, A.T., Solmus, I. (2014). The performance of alternative refrigerant gas R152a as mobile air conditioning refrigerant. Chemical Engineering, 39: 1801-1806. https://doi.org/10.3303/CET1439301

[10] Bolaji, B.O., Huan, Z.J., Borokinni, F.O. (2014). Energy performance of Eco-friendly R152a and R600a refrigerants as alternative to R134a in vapour compression refrigeration system. Analele Universităłii “Eftimie Murgu” Reşiła Anul., XXI, NR. 1.

[11] Morsi, M.E. (2015). Energy and exergy analysis of LPG (liquefied petroleum gas) as a drop in replacement for R134a in domestic refrigerators. Energy, 86: 344-353. https://doi.org/10.1016/j.energy.2015.04.035 

[12] Meng, Z., Zhang, H., Qiu, J., Lei, M. (2016). Theoretical analysis of R1234ze(E), R152 and R1234ze(E)/R152a mixtures as replacements of R134a in vapor compression system. Advances in Mechanical Engineering, 8(11): 344-353. https://doi.org/10.1177/1687814016676945

[13] Sánchez, D., Cabello, R., Llopis, R., Arauzo, I., Catalán-Gil, J., Torrella, E. (2017). Energy performance evaluation of R1234yf, R1234ze(E), R600a, R290 and R152a as low-GWP R134a alternatives. International Journal of Refrigeration, 74: 269-282. https://doi.org/10.1016/j.ijrefrig.2016.09.020

[14] Makhnatch, P., Mota-Babiloni, A., Khodabandeh, R. (2017). Experimental study of R450A drop-in performance in an R134a small capacity refrigeration. International Journal of Refrigeration, 84: 26-35. https://doi.org/10.1016/j.ijrefrig.2017.08.010  

[15] Hasheer Sk, M., Srinivas, K. (2018). Theoretical analysis of low global warming potential refrigerant as a drop in replacement of R134a in a domestic refrigerator. Iranian Journal of Energy and Environment, 9(2): 130-136. https://doi.org/10.5829/IJEE.2018.09.02.08