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Ivana, Reza Taufiqi, Imron Musthofa, and Muhammad Rezki Fitri Putra. "ANALISA EFISIENSI LAJU PENDINGINAN REFRIGERAN R-32, R-134A, R410A, DAN LPG PADA SIMULATOR REFRIGERATOR." JTAM ROTARY 5, no. 2 (2023): 70. http://dx.doi.org/10.20527/jtam_rotary.v5i1.8416.
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Efisiensi sistem refrigeran dengan fungsi sebagai fluida yang menyerap panas dalam sistem sehingga terjadi penurunan suhu melalui mekanisme evaporasi dan kondensasi. Percobaan ini dilakukan untuk mengetahui refrigeran yang mempunyai dampak laju pendinginan terbaik dengan tingkat temperatur yang berbeda sehingga dapat diamati laju pendinginan dari refrigeran R-134a, R-32, R-410a, dan LPG. Dalam prakteknya menggunakan simulator pendingin sebagai media pembelajaran dalam menerapkan prinsip kerja mesin refrigerasi. Metode penelitian yang dilakukan adalah dengan mengukur temperatur pada waktu 30 detik untuk pengambilan 1 data dan pengambilan data dilakukan selama 300 detik untuk menghasilkan 10 data pada tiap jenis refrigerant pada tekanan 10 Psi. Hasil penelitian menunjukkan refrigerant jenis LPG memiliki tingkat penurunan temperatur paling rendah diantara jenis refrigerant yang lain. Hal ini dikarenakan kinerja LPG dengan ODP sama dengan nol dan nilai GWP rendah. Kesimpulannya sistem pendingin domestik dapat menggunakan refrigeran jenis LPG di untuk penurunan temperatur yang lebih rendah. Refrigerant system efficiency by functioning as a fluid that absorbs heat in the system resulting in a decrease in temperature through evaporation and condensation mechanisms. This experiment was conducted to find out which refrigerant has the best cooling rate effect at different temperature levels so that the cooling rates of R-134a, R-32, R-410a, and LPG refrigerants can be observed. In practice using a cooling simulator as a learning medium in applying the working principles of refrigeration machines. The research method used is to measure the temperature for 30 seconds for 1 data collection and 300 seconds for data collection to produce 10 data for each type of refrigerant at a pressure of 10 Psi. LPG type refrigerant has the lowest temperature drop among other refrigerant types. This is because the performance of LPG with ODP is equal to zero and GWP is low. In conclusion, domestic refrigeration systems can use LPG type refrigerants for lower temperature drops.
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Ufie, Rikhard, Cendy S. Tupamahu, Sefnath J. E. Sarwuna, and Jufraet Frans. "KAJI PERFORMANSI REFRIGERAN R-290, R-32, DAN R-410A SEBAGAI ALTERNATIF PENGGANTI R-22." ALE Proceeding 4 (August 17, 2021): 133–39. http://dx.doi.org/10.30598/ale.4.2021.133-139.
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Refrigerant R-22 is a substance that destroys the ozone layer, so that in the field of air conditioning it has begun to be replaced, among others with refrigerants R-32 and R-410a, and also R-290. Through this research, we want to know how much Coefficient of Performance (COP) and Refrigeration Capacity (Qe) can be produced for the four types of refrigerants. The study was carried out theoretically for the working conditions of the vapor compression cycle with an evaporation temperature (Tevap) of 0, -5, and -10oC, a further heated refrigerant temperature (ΔTSH) of 5 oC, a condensation temperature (Tkond) of 45 oC and a low-cold refrigerant temperature. (ΔTSC) 10 oC and compression power of 1 PK . The results of the study show that the Coefficient of Performance (COP) in the use of R-22 and R-290 is higher than the use of R-32 and R-410a, which are 4,920 respectively; 4,891; 4.690 and 4.409 when working at an evaporation temperature of 0 oC; 4.260; 4,234; 4.060 and 3.812 when working at an evaporation temperature of -5 oC; and amounted to 3,730; 3,685; 3,550 and 3,324 if working at an evaporation temperature of -10 oC. Based on the size of the COP, if this installation works with a compression power of 1 PK, then the cooling capacity of the R-22 and R-290 is higher than the R-32 and R-410a, which are 3,617 respectively. kW; 3,597 kW; 3,449 kW and 3,243 kW. If working at an evaporation temperature of 0 oC; 3.133 kW; 3.114 kW; 2,986 kW and 2,804 kW if working at an evaporation temperature of -5 oC; and 2,741 kW; 2,710 kW; 2,611 kW and 2,445 kW if working at an evaporation temperature of -10oC.
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Al-Zahrani, Ahmed. "Investigating New Environmentally Friendly Zeotropic Refrigerants as Possible Replacements for Carbon Dioxide (CO2) in Car Air Conditioners." Sustainability 16, no. 1 (2023): 358. http://dx.doi.org/10.3390/su16010358.
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The widespread use of automobiles and the increased duration spent within automobiles equipped with air conditioning systems have prompted various countries to enforce regulations that advocate for eco-friendly cooling substances (refrigerants) characterized by a slight global warming potential (GWP) and the absence of an ozone depletion potential (ODP). The imperative for automobiles to possess air conditioning systems that are both high-performing and eco-conscious has emerged as a means to mitigate their ecological impact, reduce fuel usage, and minimize carbon emissions. Zeotropic refrigerants, with a lower GWP than traditional alternatives, contribute to sustainability in car air conditioning by reducing the environmental impact and enhancing the energy efficiency, aligning with global regulations and fostering innovation in the automotive industry. This shift signifies a commitment to mitigating climate change and adopting environmentally conscious practices. The objective of the present study is to introduce blends of zeotropic refrigerants based on CO2 (R-744), namely R455A (a blend of R-744, R-32, and R-1234yf), R469A (a blend of R-744, R-32, and R-125), and R472A (a blend of R-744, R-32, and R-134a), to enhance the thermodynamic performance of pure CO2 refrigerant. Through the utilization of the Aspen HYSYS V11 software, an investigation is carried out involving thermodynamic energy and exergy analyses, as well as system optimization for an automotive air conditioning (AAC) system utilizing these novel zeotropic refrigerant blends, in comparison with the use of R-744 as the refrigerant. The study delves into the impact of parameters such as average evaporator temperature, condenser/cooler pressure, refrigerant flow rate, and condenser/cooler outlet temperature on AACs’ output parameters and subsequently presents the findings. The outcomes reveal that, under equivalent operational circumstances, the adoption of R455A, R469A, and R472A offers improvements in coefficient of performance (COP) by 35.4%, 18.75%, and 2%, respectively, when compared to R744. This shift is advantageous as it mitigates leakage-related issues stemming from the elevated operational pressure of R744 and eliminates the need for cumbersome equipment. R455A and R469A obtain the greatest COP and exergy efficiency (ηex) values, measuring 4.44 and 4.55, respectively, at the identical operating conditions with optimal condenser/cooler pressures of the examined blends. Furthermore, eco-friendly refrigerants R455A and R472A are recommended for integration into AAC systems in vehicles, as they help combat global warming and protect natural surroundings and leakage issues.
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Al-Zahrani, Ahmed. "Energy and Exergy Analysis on Zeotropic Refrigerants R-455A and R-463A as Alternatives for R-744 in Automotive Air-Conditioning System (AACs)." Processes 11, no. 7 (2023): 2127. http://dx.doi.org/10.3390/pr11072127.
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The popularity of vehicles and the increased time spent in cars with air conditioning systems has led to regulations in many countries that require the use of environmentally friendly refrigerants with minimal global warming and zero ozone depletion potential (GWP and ODP). Cars need high-performance, eco-friendly air conditioning systems to reduce their impact on the environment, lower fuel consumption, and decrease carbon emissions. The aim of the current work was to propose CO2-based blend zeotropic refrigerants, R-455A (R-744/32/1234yf) and R-463A (R-744/32/125/1234yf/134a), to improve the thermodynamic performance of pure CO2 refrigerants. The thermodynamic energy and exergy analysis and system optimization of an AAC system for the new zeotropic refrigerant blends compared to carbon dioxide (R-744), using Aspen HYSYS software, were investigated. The influence of cooler/condenser pressure, average evaporator temperature, cooler/condenser outlet temperature, and refrigerant flow rate on the cycles’ COP and exergy efficiency were conducted and are presented. The results showed that, at the same operating condition parameters, the cycle COP improved by 57.6 and 76.5% when using R455A and R463A instated of R744, respectively, with the advantage of reducing leakage problems due to the higher operating pressure of R744 (5–7 times higher than those of R455A and R463A), as well as requiring heavy equipment, but at optimal operating condition parameters, R744 and R-463A had a maximum COP of 14.58 and 14.19, respectively. The maximum COPs of R744, R455A, and R463A based on the optimal pressure of the cooler/condenser were 3.1, 4.25, and 5.4, respectively. Additionally, regarding the need for environmentally friendly air conditioning systems with acceptable performance in cars due to their impact on the environment and their contribution to global warming, the blend R455A is recommended for use as a refrigerant in AAC systems.
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Mudana, I. Nyoman, Yanu Prapto Sudarmojo, and I. Gusti Ngurah Janardana. "Studi Pengaruh Jenis Refrigerant Terhadap Pemakaian Daya Listrik Pada Mesin Pengkondisian Udara (AC)." Jurnal SPEKTRUM 5, no. 1 (2018): 146. http://dx.doi.org/10.24843/spektrum.2018.v05.i01.p21.
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Air conditioning is strongly influenced by Refrigerant. R.22 refrigerant is currently still widely used with high level of electric power consumption. The purpose of this research is to analyze the influence of types of refrigerant to the electric power consumption of AC by measuring the electric power requirement of each Refrigerant (R.22, R.410, R.32, EnggasM60 and Isceon MO99). The results showed that R.410 uses 335 Watt with the total cost of Rp 42,210 / month, R.32 uses 328 Watt power with the total cost of Rp 41.328 / month, R.22 uses 271 Watt power with theotal cost of Rp 34.146 / month, Huffin M60 uses 262 Watt power with the total cost of Rp 33.012 / month. While Isceon M099 requires 262 Watt with the total cost of Rp 33.012 / month at the temperature of 24,4 ° C.
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Bell, Ian H. "Mixture Model for Refrigerant Pairs R-32/1234yf, R-32/1234ze(E), R-1234ze(E)/227ea, R-1234yf/152a, and R-125/1234yf." Journal of Physical and Chemical Reference Data 52, no. 1 (2023): 013101. http://dx.doi.org/10.1063/5.0135368.
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In this work, thermodynamic models based on the corresponding states framework with departure terms are developed for the refrigerant pairs R-32/1234yf, R-32/1234ze(E), R-1234ze(E)/227ea, R-1234yf/152a, and R-125/1234yf. These models are based on new measurements of density, speed of sound, and phase equilibria, combined with the data available in the literature. The model for R-32/1234yf is most comprehensive in its data coverage, with speed of sound deviations within 1%, density deviations within 0.1%, and bubble- and dew-point pressure deviations within 1%. The other mixtures have generally more limited data availability but a similar goodness of fit.
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Kim, Dennis K., and Peter B. Sunderland. "Viability of Various Sources to Ignite A2L Refrigerants." Energies 14, no. 1 (2020): 121. http://dx.doi.org/10.3390/en14010121.
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Environmental considerations are motivating the adoption of low global warming potential refrigerants. Most of these are mildly flammable, i.e., A2L. Their susceptibility to ignition from various ignition sources is poorly understood, particularly for the stoichiometric and quiescent mixtures that are emphasized here. The viability of fifteen residential ignition sources to ignite four A2L refrigerants is considered. Tests are performed in a windowed chamber with a volume of 26 L. The refrigerants are R-32 (difluoromethane); R-452B (67% R-32, 26% R-1234yf, and 7% pentafluoroethane); R-1234yf (2,3,3,3-tetrafluoropropene); and R-1234ze (1,3,3,3-tetrafluoropropene). Two types of ignition sources are confirmed here to be viable: a resistively heated wire at 740 °C and open flames. When the refrigerant concentration was increased slowly, candle flames and butane flames extinguished before initiating any large deflagrations. Eleven other sources were not viable: a smoldering cigarette, a butane lighter, friction sparks, a plug and receptacle, a light switch, a hand mixer, a cordless drill, a bread toaster, a hair dryer, a hot plate, and a space heater. The difficulty to ignite these refrigerants in air is attributed to their long quenching distances (up to 25 mm). Under some conditions the refrigerants were observed to act as flame suppressants.
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Ashfi Rayhan, Fajri, Amir Marasabessy, Wiwin Sulistyawati, Dea Zulpiana Putri, Anandita Fatihah, and Deva Natasya. "Thermodynamic Performance Comparison of Refrigeration Systems using R-134a, R-744, and R-32 for Indonesian Fishing Boats." Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 128, no. 1 (2025): 19–31. https://doi.org/10.37934/arfmts.128.1.1931.
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Indonesian fishermen are lagging behind in the global fishing Industry due to several reasons such as the absence of effective fish refrigeration storage facilities. This is observed from the fact that the fishing boats use conventional refrigerants, R-134a, considered capable of damaging the ozone and climate. Meanwhile, the boats in Europe are using carbon dioxide, R-744, which has been updated and believed to be better for nature. Therefore, this study aimed to compare and analyze the enthalpy, energy, and coefficient of performance (COP) in the cooling system of fishing boats varied at R-134a, R-744 and R-32. The thermodynamic simulations were conducted by varying the pressure from 800 Kpa to 1000 Kpa. The temperatures used were also in different categories, including low from -2°C to -6°C and high from 31°C to 40°C. The results showed that the compressor with R-744 working fluid produced the highest energy consumption and had the lowest COP compared to R-134a and R-32. However, the use of R-744 in Indonesia fishing boats was observed to be a challenge. These findings highlight the potential for adopting R-32 as a more efficient and environmentally friendly refrigerant for Indonesian fishing boats, addressing global sustainability goals while improving local competitiveness in the fishing industry.
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Muliawan, Rizki, and Ari Darmawan Pasek. "PREDICTING OF REFRIGERANT LEAKAGE IN A CONDITIONED ROOM: A NUMERICAL STUDY LEAKS DISTRIBUTION R-32 REFRIGERANT IN A/C SPLIT UNIT." ASEAN Engineering Journal 12, no. 2 (2022): 11–18. http://dx.doi.org/10.11113/aej.v12.16499.
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Hydrocarbon Refrigerant R-32 called difluoromethane is one alternative solution used for Air Conditioning (A/C) unit split, but the weakness is flame property. This study investigates and analyzes flammable refrigerant difluoromethane distributions in the room affected by the A/C unit's leakage. It discusses the distribution of flammable refrigerant R-32 (difluoromethane) in an air-conditioned room. The simulation uses three variations of mass flow rate (leakage) and three airflow rate variations: low, medium, and high cold airflow velocity. Numerical calculations are used in CFD ANSYS FLUENT software with a model developed by Species Transport, SIMPLE algorithm, solver using pressure-based, mesh type is the dominant quadrilateral (rectangle). Turbulent modeling uses K-Epsilon standards. CFD analysis in the transient system condition results from numerical simulation, indicating that the leak will run out after 180 seconds with 0.005 kg/s (0.5 m/s). The moderate leak rate of 0.002 kg/s for R-32 is 450 seconds (7.5 minutes). The slower 0.001 kg/s with 0.1 m/s airflows for the R-32 ends after 900 seconds (15 minutes). The air and flow mass flow can affect the distribution and directly difluoromethane to the conditioned room. The effect of airflow rates and positioning holes in the concentration leaks is also analyzed when the unit's refrigerant leak is indoors as the air conditioner works.
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Alsouda, Fadi, Nick S. Bennett, Suvash C. Saha, and Mohammad S. Islam. "A Novel Direct-Expansion Radiant Floor System Utilizing Water (R-718) for Cooling and Heating." Energies 17, no. 17 (2024): 4520. http://dx.doi.org/10.3390/en17174520.
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While forced-air convective systems remain the predominant method for heating and cooling worldwide, radiant cooling and heating systems are emerging as a more efficient alternative. Current radiant cooling systems primarily rely on hydronic chilled water systems. This study introduces direct-expansion radiant cooling as a novel technique that could enhance the efficiency of radiant cooling and reduce its environmental impact. Water (R-718) has been tested as a refrigerant due to its favorable thermodynamic properties and environmental advantages; however, to the author’s knowledge, it has yet to be tested in direct-expansion radiant cooling. This research investigated several refrigerants, including water (R-718), ammonia (R-717), R-410a, R-32, R-134a, and R-1234yf, for this application. The findings indicate that water demonstrates efficiency comparable to other non-natural refrigerants, making it a promising candidate, given its favorable thermodynamic properties and substantial environmental benefits. Despite challenges such as a high compression ratio necessitating multi-stage compression, a high compressor discharge temperature exceeding 300 °C and requiring specialized blade materials, and a high suction volume flow rate, direct-expansion radiant cooling operates within a different temperature range. Consequently, the compressor discharge temperature can be reduced to 176 °C, and the compression ratio can be lowered to approximately 3.5, making water a more viable refrigerant option for this application.
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Küpper, Hans-Dieter, Alessandro Pianetti, and Samer Saab. "A2L low GWP HFO based refrigerant solutions in heat pump applications to drive energy efficiency, safety, and sustainability even in building restoration." E3S Web of Conferences 343 (2022): 04002. http://dx.doi.org/10.1051/e3sconf/202234304002.
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Driven by energy efficiency requirements and legal restrictions like F-Gas Regulation Heat Pump OEM supplier are looking for alternative refrigerant solutions. HFO based low GWP refrigerants can help increasing the system efficiency, expanding the operating temperature range while reducing CO2 emissions. For building restoration in particular, high flow temperatures (for existing hydronic heating system) are essential for convenient and cost-and energy-efficient replacements of fossil fuel boilers. A2L classified refrigerants provide extended application range at highest safety level versus A3 classified refrigerants, but R-32 still carries a Global Warming Potential (GWP) of 675 making it a transitional solution. This paper compares different relevant parameters and points out the advantages provided by HFO A2L low GWP refrigerants (like R-454B and R-454C) for a wide capacity range of air to water and brine to water heat pumps. A special focus is put on the application of building restoration.
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Mahdi, Loauy Abd Al-Azez, and Ahmed Yusef Lateif. "Prediction of Heat Transfer Coefficient and Pressure Drop in Wire Heat Exchanger Working with R-134a and R-600a." Journal of Engineering 25, no. 11 (2019): 1–20. http://dx.doi.org/10.31026/j.eng.2019.11.01.
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An experimental and theoretical works were carried out to model the wire condenser in the domestic refrigerator by calculating the heat transfer coefficient and pressure drop and finding the optimum performance. The two methods were used for calculation, zone method, and an integral method. The work was conducted by using two wire condensers with equal length but different in tube diameters, two refrigerants, R-134a and R-600a, and two different compressors matching the refrigerant type. In the experimental work, the optimum charge was found for the refrigerator according to ASHRAE recommendation. Then, the tests were done at 32˚C ambient temperature in a closed room with dimension (2m*2m*3m). The results showed that the average heat transfer coefficient for the R-600a was higher than the R-134a, so the length of the wire tube was longer with R-134a than R-600a. The pressure drop for the smaller tube diameter was higher than the other tube. The second law thermodynamic efficiency was higher for R-600a, which reached 41%. The entropy generation minimization analysis showed that the R-600a refrigerant type and smaller tube diameter are approached the optimum point.
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Shiflett, Mark, and Kalin Baca. "Separation of Azeotropic Refrigerant Mixtures Using Ionic Liquids." ECS Meeting Abstracts MA2022-02, no. 55 (2022): 2063. http://dx.doi.org/10.1149/ma2022-02552063mtgabs.
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Refrigeration and air-conditioning systems are widespread throughout modern society, from the refrigerated cold chain that provides fresh foods and storage of medicines to the air conditioning of homes and buildings. Refrigeration is viewed as one of the most transformative engineering achievements of the 20th century and the demand for cooling will continue to increase as economic conditions improve and the climate continues to warm; however, refrigerants do come with an environmental cost. In 1987, the Montreal Protocol phased out chlorofluorocarbon (CFC) refrigerants because of their high ozone depletion potential (ODP). The replacements, typically mixtures of hydrofluorocarbons (HFCs), are safe for the Earth's ozone layer, but most have high global warming potentials (GWPs). HFCs account for 7.8% of total global greenhouse gas emissions, with 63% of that from “indirect” emissions (i.e., energy for running the system). As a result, 197 countries signed the Kigali agreement in 2016 to phase out high-GWP HFCs, with the goal of reducing emissions by 80% in the next 20 years. Millions of metric tons (mts) of high-GWP refrigerants will need to be reclaimed, but there are no good methods for separating and recycling the individual components, given that many are azeotropic mixtures. Currently, there is no means of separating azeotropic HFC mixtures, and the refrigerants will ultimately have to be incinerated. The commercial HFC mixture R-410A containing 50 wt.% HFC-32 (GWP = 675) and 50 wt.% HFC-125 (GWP = 3500) is a prime example. The HFC-32 can be reused when separated in new low-GWP products such as R-454B (69 wt% HFC-32 and 31 wt% HFO-1234yf) with a 75% lower GWP than R-410A. Ionic liquids are being developed that can separate azeotropic HFC mixtures based on differences in solubility and used as entrainers in extractive distillation. This presentation will provide experimental data on the solubility of HFCs in ionic liquids that have been measured using gravimetric microbalances and modeling using the Peng-Robinson equation of state. ASPEN Plus simulations will show how a pilot process has been designed that can continuously separate azeotropic refrigerant mixtures such as R-410A.
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bin Ismail, Azhar, Li Ang, Kyaw Thu, and Kim Choon Ng. "Low Temperature Waste Heat Driven Refrigeration Cycle." Applied Mechanics and Materials 819 (January 2016): 241–44. http://dx.doi.org/10.4028/www.scientific.net/amm.819.241.
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This work explores the utilization of alternative refrigerants to the conventional silica gel + water adsorption pair for the adsorption chiller cycle. Water as the working fluid in the cycle limits the cooling temperatures to above 0°C due to its triple point. The activated carbon Maxsorb III is thus considered as the adsorbent due to its high micro-porous characteristics which lead to higher uptake values. The isotherms of this adsorbent with natural refrigerant Propane, n-butane as well as refrigerants HFC-134a, R507a and R-32 are fitted to the Dubinin-Astakhov equation and the parameters tabulated. With these isotherms, the performances of these pairs with respect to their Specific Cooling Effects (SCE) are compared for assorted cooling temperature, ambient temperature and waste temperature requirements. It was found that the natural refrigerant propane exhibits the most favorable operational conditions when the required cooling temperature is below 0°C. A mathematical model is thus developed to predict the cycle of the propane cycle and is found to show a good fit to the experimental results.
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Subagia, I. Wayan Adi, I. Dewa Made Susila, Ketut Bangse, and I. Nyoman Suamir. "Kajian termodinamik kinerja AC split: studi kasus pada bangunan pendidikan dengan menerapkan program komputer." Journal of Applied Mechanical Engineering and Green Technology 3, no. 1 (2022): 36–42. http://dx.doi.org/10.31940/jametech.v3i1.36-42.
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This paper presents a thermodynamic study on energy performance of a split AC system with R-32 for the application of educational buildings at the Bali State Polytechnic. The study was conducted using a standalone computer program U-CoolS V.1.12 which was developed on the EES (Engineering Equation Solver) V11,334 program. A thermodynamic model was developed and validated using data from the technical specifications of various types of split AC. Thermodynamic studies were carried out based on variations in ambient temperature in the Bali Region. The effect of two operating parameters of a split AC system, namely the condensing temperature in the condenser and the evaporation temperature of the refrigerant in the evaporator, on the compressor performance and energy performance of the AC system is simulated. Thermodynamic simulation results show the strong influence of condensing temperature and evaporation temperature on compressor performance and overall energy performance of the split AC system. It was found that for 1 °C increase in condensing temperature, the compressor power increased quite significantly around 2.1%, the cooling capacity of the split AC system decreased by 1.8%, COP and EER also decreased by 3.9%. Meanwhile, for 1 °C increase in evaporation temperature, it was found an increase in compressor power consumption of around 0.31%, an increase in cooling capacity of 4.4% and an increase in COP and EER of 4.1%. The results of this thermodynamic study also show that the split AC system performance using R-32 refrigerant has a very good COP range from 3.27 to 5.95 with the implication that R-32 refrigerant has the potential to be a refrigerant for a split AC system.
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Banjerd, Saengchandr, Sukontanakarn Viroch, and Waiyagan Kriangkrai. "Experimental study of compressor electric current detection fora split-type air conditioner affects energy savings." International Journal of Electrical and Computer Engineering (IJECE) 13, no. 3 (2023): 2660–68. https://doi.org/10.11591/ijece.v13i3.pp2660-2668.
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The paper presents an experimental study that aims to measure the compressor electric current of a split-type air conditioner for analyzing the various abnormal condition of the R-32 refrigerant pressure, especially for detecting compressor electric current while occurring dirt in the evaporator coil and condenser coil. The method was to install sensor devices to measure the temperature and humidity of inlet air and outlet air, and the velocity of the air outlet of the evaporator unit. In condenser unit was to measure the electric current compressor and electric power input. All data from sensors send to the Arduino board and using Parallax Data Acquisition (PLX-DAQ) Excel Macro for the record. The results show physical behavior and the changing of compressor electric current according to the abnormal condition of the refrigerant system, blocking of condenser and evaporator coil.
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HIGASHI, Yukihiro, Akio MIYARA, and Shigeru KOYAMA. "A111 Measurements of Thermodynamic Properties for Ternary R-1234ze(E)+R-32+CO_2 Refrigerant Mixtur." Proceedings of the Thermal Engineering Conference 2012 (2012): 1–2. http://dx.doi.org/10.1299/jsmeted.2012.1.
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Chaiyat, Nattaporn. "Thermal Performance Curve Analysis for Enhancement of an Air Conditioner in Thailand." International Journal of Air-Conditioning and Refrigeration 27, no. 03 (2019): 1930003. http://dx.doi.org/10.1142/s2010132519300039.
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This study presents a method for analysing air conditioner efficiency by using a thermal performance curve. Enhancement techniques consisting of the use of a phase change material (PCM), a vapor compression heat pump (VCHP), ultrasound, drop-in refrigerant, a commercial R-32 air conditioner using ultrasound and a double-storage tank are reported under the weather conditions in Thailand. For the PCM, Rubitherm20 (RT-20) in the forms of a paraffin ball and a plastic pack was selected to cool the return air of the evaporator, which directly caused decreases in power consumption of 7.85% and 5.78%, respectively. The R-123 VCHP was integrated with the air conditioner at the condenser to receive and boost rejected heat to the hot water temperature of 60–70∘C. Ultrasonic wave generators at 42[Formula: see text]kHz frequency were installed at the evaporator to improve heat transfer characteristics and reduce the electrical power usage of the air conditioner by 8%. The R-32 drop-in refrigerant technique was tested in an R-410a air conditioner model. The R-32 unit showed the advantages of a smaller environmental impact and a higher cooling energy efficiency ratio (EER) compared with that of the R-410a unit. Moreover, the commercial R-32 air conditioner and a 40 kHz ultrasonic generator were integrated. The combined unit revealed a higher EER of 7.69% compared with that of the conventional commercial R-32 unit. For a double-storage tank, it was shown that the maximum hot water temperature in the storage tank was approximately 49∘C. The highest effective method to enhance the cooling capacity of air-conditioner is the technique of R-32 air conditioner and ultrasonic wave for increasing the cooling efficiency of 8.54%.
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Sumardi, K., N. Nahadi, and M. Mutaufiq. "Experimental study of hydrocarbon refrigerant (R-1270) to replace R-32 in residential air conditioning system." Journal of Physics: Conference Series 1469 (February 2020): 012174. http://dx.doi.org/10.1088/1742-6596/1469/1/012174.
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Hozumi, Tsutomu, Haruki Sato, and Koichi Watanabe. "Speed-of-Sound Measurements in Gaseous Binary Refrigerant Mixtures of Difluoromethane (R-32) + 1,1,1,2-Tetrafluoroethane (R-134a)." Journal of Chemical & Engineering Data 42, no. 3 (1997): 541–47. http://dx.doi.org/10.1021/je960282b.
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avi, P. S. R. "Design of Roll Bond Evaporator for Room Air Conditioner using Eco-friendly Refrigerant, R-32 (DiFluoroMethane)." International Journal of Innovative Research in Science, Engineering and Technology 5, no. 6 (2016): 9537–43. http://dx.doi.org/10.15680/ijirset.2015.0506005.
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Fu, Haiyu, Leping Zhou, and Xiaoze Du. "Low-pressure evaporation characteristics of R-32 refrigerant film on copper surface: A molecular dynamics study." International Journal of Heat and Mass Transfer 239 (April 2025): 126572. https://doi.org/10.1016/j.ijheatmasstransfer.2024.126572.
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Chaiyat, Nattaporn. "Thermal Efficiency Enhancement of an R-32 Air Conditioner and the Ultrasonic Wave Technique." International Journal of Air-Conditioning and Refrigeration 28, no. 03 (2020): 2050023. http://dx.doi.org/10.1142/s2010132520500236.
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This work presents a technique to improve the thermal performance of an R-32 air conditioner by using ultrasonic waves. Two 1-TR air conditioners — one with and one without 40[Formula: see text]kHz/50[Formula: see text]W ultrasonic generators — were tested under controlled conditions in a 3.6[Formula: see text]m [Formula: see text][Formula: see text]m [Formula: see text][Formula: see text]m room. The air temperature and humidity conditions entering the condenser and evaporator coils were controlled under 12 conditions to mimic the climate of Thailand. The testing results indicated that the average energy efficiency ratio (EER) of the modified ultrasonic R-32 air conditioner unit was 3.685[Formula: see text]kWth/kWe and the normal R-32 unit without the ultrasonic generators was 3.375[Formula: see text]kWth/kWe. The testing conditions also indicated that the cooling efficiency of the modified system could be increased by approximately 7.69%. Moreover, the convective heat transfer coefficient of the modified ultrasonic R-32 unit was approximately 17.36% higher than that of the normal R-32 unit without the ultrasonic generators because the ultrasonic waves could increase the turbulence in the refrigerant flow and decrease the condensed water at the fan coil unit. In terms of economic results, the payback period of the modified unit based on the climate of Thailand ranged from 0.8–1.2 y, leading to a savings in power consumption of approximately 400–620[Formula: see text]kWh/y.
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Saengchandr, Banjerd, Viroch Sukontanakarn, and Kriangkrai Waiyagan. "Experimental study of compressor electric current detection for a split-type air conditioner affects energy savings." International Journal of Electrical and Computer Engineering (IJECE) 13, no. 3 (2023): 2660. http://dx.doi.org/10.11591/ijece.v13i3.pp2660-2668.
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The paper presents an experimental study that aims to measure the compressor electric current of a split-type air conditioner for analyzing the various abnormal condition of the R-32 refrigerant pressure, especially for detecting compressor electric current while occurring dirt in the evaporator coil and condenser coil. The method was to install sensor devices to measure the temperature and humidity of inlet air and outlet air, and the velocity of the air outlet of the evaporator unit. In condenser unit was to measure the electric current compressor and electric power input. All data from sensors send to the Arduino board and using Parallax Data Acquisition (PLX-DAQ) Excel Macro for the record. The results show physical behavior and the changing of compressor electric current according to the abnormal condition of the refrigerant system, blocking of condenser and evaporator coil.
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Dobson, M. K., and J. C. Chato. "Condensation in Smooth Horizontal Tubes." Journal of Heat Transfer 120, no. 1 (1998): 193–213. http://dx.doi.org/10.1115/1.2830043.
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An experimental study of heat transfer and flow regimes during condensation of refrigerants in horizontal tubes was conducted. Measurements were made in smooth, round tubes with diameters ranging from 3.14 mm to 7.04 mm. The refrigerants tested were R-12, R-22, R-134a, and near-azeotropic blends of R-32/R-125 in 50 percent/50 percent and 60 percent/40 percent compositions. The study focused primarily on measurement and prediction of condensing heat transfer coefficients and the relationship between heat transfer coefficients and two-phase flow regimes. Flow regimes were observed visually at the inlet and outlet of the test condenser as the heat transfer data were collected. Stratified, wavy, wavy annular, annular, annular mist, and slug flows were observed. True mist flow without a stable wall film was not observed during condensation tests. The experimental results were compared with existing flow regime maps and some corrections are suggested. The heat transfer behavior was controlled by the prevailing flow regime. For the purpose of analyzing condensing heat transfer behavior, the various flow regimes were divided into two broad categories of gravity-dominated and shear-dominated flows. In the gravity dominated flow regime, the dominant heat transfer mode was laminar film condensation in the top of the tube. This regime was characterized by heat transfer coefficients that depended on the wall-to-refrigerant temperature difference but were nearly independent of mass flux. In the shear-dominated flow regime, forced-convective condensation was the dominant heat transfer mechanism. This regime was characterized by heat transfer coefficients that were independent of temperature difference but very dependent on mass flux and quality. Heat transfer correlations that were developed for each of these flow regimes successfully predicted data from the present study and from several other sources.
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Kumar, Subhash, PJ bansod, and Akhya Kumar Behera. "Experimental and Performance Analysis of R-32 and R290 Heat Pump Driven Air Conditioning System." International Research Journal of Multidisciplinary Scope 06, no. 02 (2025): 885–95. https://doi.org/10.47857/irjms.2025.v06i02.03567.
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A thorough performance analysis of a heat pump air conditioning system for both heating and cooling applications is presented in this research. The purpose of the study is to assess the system's overall performance, energy usage, and efficiency under various operating circumstances. The study makes use of a variety of experimental measurements. An outline of the heat pump air conditioning system's parts and operation is given at the start of the analysis. Important factors including compressor power usage, ambient temperature, refrigerant flow rate, and indoor/outdoor temperature differentials are all monitored during the experimental setting. These measurements, which take into account both heating and cooling modes, are gathered under varied working conditions. For HVAC engineers, researchers, and policymakers, the performance analysis of the heat pump air conditioning system provided in this paper is an invaluable resource. The insights gained from this study contribute to the on-going efforts to improve the design and operation of heat pump systems for heating and cooling applications, fostering sustainability and energy conservation in the built environment.
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Sianipar, Celvin, and Risko Ambarita. "Analisis dan Eksperimental Performasi Kompresi Uap 2 Tingkat dengan Variasi 4 Siklus." Jurnal Kolaborasi Sains dan Ilmu Terapan 1, no. 1 (2023): 1–5. http://dx.doi.org/10.69688/juksit.v1i1.1.
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Keberadaan Air Conditioner (AC) tidak terlepas dari aspek kehidupan sehari-hari. Pendingin udara memanfaatkan prinsip termodinamika dari siklus kompresi uap. COP merupakan parameter untuk melihat performa dari mesin pendingin. Pada penelitian ini, salah satu cara untuk meningkatkan COP pada mesin Pendingin adalah dengan memodifikasi siklus 1 tahap menjadi siklus 2 tahap. Makalah ini mengulas perbandin gan model siklus kompresi uap dua tahap dengan beberapa variasi.Perbandingan ini menggunakan software ASPEN PLUS V10 untuk melihat performa masing-masing varian. Untuk fluida kerja (Refrigerant) yang digunakan adalah R-32. Dari hasil simulasi, varian no III menunjukkan nilai COP yang lebih tinggi dibandingkan varian lainnya.
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Yoon, Seok Ho, and Min Soo Kim. "Investigation of Circumferential Variation of Heat Transfer Coefficients During In-Tube Evaporation for R-22 and R-407C Using Liquid Crystal." Journal of Heat Transfer 124, no. 5 (2002): 845–53. http://dx.doi.org/10.1115/1.1484110.
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Heat transfer coefficients during evaporation in a horizontal smooth tube for R-22 and R-407C (R-32/125/134a, 23/25/52 wt.%) have been measured using thermochromic liquid crystal. Focus has been put on the circumferential variation of heat transfer coefficients at several cross-sections of the test tube with inner diameter of 11.3 mm for several vapor qualities of refrigerant. The inner wall temperatures were calculated by one dimensional heat conduction equation from the measured outer wall temperatures, which were obtained using an image processing technique with thermochromic liquid crystal (TLC). The relation between measured temperature and color information (Red-Green-Blue values) of thermochromic liquid crystal was calibrated by a neural network method. Results show that circumferential variation of heat transfer coefficients for R-22 is quite large with the highest heat transfer coefficient at the top of the tube. For zeotropic mixture of R-407C, similar trend has been observed with less difference between the heat transfer coefficients at the top and bottom than that of R-22.
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Ahmed Khan, Adeel, Muhammad Ehtesham ul Haque, Farjad Siddiqui, Syed Muhammad Taha Nasir, Talha Shafique, and Hassan Khalid. "Reducing Energy Consumption of Refrigerator Compressor using Aluminum Oxide Nanoparticles." Memoria Investigaciones en Ingeniería, no. 26 (July 3, 2024): 38–56. http://dx.doi.org/10.36561/ing.26.3.
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Refrigeration has become an integral part of our daily lives and can be regarded as a process whose replacement is nearly impossible. Therefore, the only way of making this process efficient is by reducing the energy consumed by the components of refrigerators. One way of doing this is to reduce the power consumption of compressor by the addition of nanoparticles either in a refrigerant or in a lubricant. This study focusses on producing nanolubricant (Al2O3/Synthetic lubricant) and dispersing the nanolubricant into R-134a compressor. This study investigates that how much power can be reduced when Aluminum oxide (Al2O3) nanoparticles dispersed in SL-32 lubricant (base fluid). A comparison between SL-32 lubricant with and without the addition of Aluminum oxide nanoparticles was done and it showed a reduction of 0.913% in current consumption and 2.74% in power at the same initial temperature of 31°C in both cases. Hence it can be concluded that Alumina nanoparticles can be utilized to reduce the energy utilized by compressors by creating a nanolubricant with SL-32 lubricant.
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Baca, Kalin, Greta Olsen, Dorothy Haggard, Madelyn Bennett, Lucia Matamoros Valenciano, and Mark Shiflett. "The Impact of Phase Changes of Imidazolium Based Ionic Liquids on the Solubility of Hydrofluorocarbons." ECS Meeting Abstracts MA2022-02, no. 55 (2022): 2075. http://dx.doi.org/10.1149/ma2022-02552075mtgabs.
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Project EARTH (Environmentally Applied Research Toward Hydrofluorocarbons) is focused on developing sustainable processes for selectively separating refrigerant mixtures with high global warming potentials. The initial focus of the project is R-410A which is widely used in both commercial refrigeration systems and residential air conditioning. It is an azeotropic mixture containing 50 wt.% HFC-32 (CH2F2) and 50 wt.% HFC-125 (CHF2CF3). The separation approaches being investigated include membranes, porous media, and the use of ionic liquids as entrainers for extractive distillation. This poster will describe the work being conducted using ionic liquids and will specifically focus on the impact of phase changes of imidazolium based ionic liquids that are solid at room temperature on the solubility of HFC-32 and HFC-125. The poster will include an overview of how we use specialized equipment including a High-Pressure View Cell and Hiden Isochema IGA gravimetric microbalance to build a comprehensive understanding of these solubility differences.
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Tahasildar, Mohammed Faris, and Sachidananda Hassan Krishanmurthy. "Analysis of microchannel heat exchanger based on channel geometry." International Journal for Simulation and Multidisciplinary Design Optimization 13 (2022): 14. http://dx.doi.org/10.1051/smdo/2022003.
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The use of air conditioning in heating ventilating and air-conditioning (HVAC) industry has risen steadily over the last few decades. The goal of the system is to provide a comfortable indoor environment by the process of removal or addition of heat. There are various systems and components which have been in constant use over the years and have evolved with the needs of the user and the environment too. In this research paper attempt have been made to study microchannel heat exchangers in condenser section of package units. The idea is to see how an increase in cross-sectional area through the microchannel increases the area of heat transfer. The effect of grooved cross-section which results in increase of rate of cooling for a fluid flowing through the channel have been studied. R-32 (Freon Refrigerant) is considered as refrigerant along with water for the study using CFD analysis. Two designs were considered for the study considering circular cross section and the grooved cross section considering the channel geometry. From the results of CFD analysis, it can be stated that grooved cross section has performed better in terms of heat transfer and temperature drop as compared to circular cross section.
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Jumhan, Amri, and Audri Deacy Cappenberg. "ANALISIS KINERJA SISTEM PENDINGIN RUANG PALKAH IKAN DENGAN MENGGUNAKAN REFRIGERAN R-22 DAN HIDROKARBON (MC-22)." JURNAL KAJIAN TEKNIK MESIN 2, no. 1 (2017): 14–25. http://dx.doi.org/10.52447/jktm.v2i1.570.
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Proses pendinginan atau refrigerasi sangat diperlukan oleh nelayan untuk mempertahankan mutu dari hasil tangkapan ikan. Dan perlu adanya teknologi pendinginan ikan yang mampu digunakan dalam jangka waktu lama. Teknik refrigerasi modern yang digunakan dengan mengaplikasikan refrigeran sebagai media utama pengganti es balok. Pada saat ini, refrigeran yang umum dipakai dalam proses pendinginan yaitu dengan menggunakan jenis R-22 yang ke depannya harus digantikan dengan refrigeran lain yang lebih ramah lingkungan dan aman. Penelitian ini dilakukan untuk mencoba mengganti dengan refrigeran hidrokarbon MC-22 pada sistem pendingin kompresi uap. Pada penelitian ini difokuskan pada kinerja kompresor dan koefisien prestasi pada objek kapal KM. Putra Berlian dengan kapasitas muatan ikan mencapai 100 ton. Dari analisis yang telah dilakukan refrigeran keluar dari evaporator -20°C. Refrigeran keluar dari kompresor 40°C. Refrigeran keluar dari kondensor 32°C. Dan refrigeran keluar katup ekspansi menuju evaporator -20°C dengan daya pendingin 60 kW. Dari penghitungan pada sistem refrigerasi ini didapat hasil bahwa terdapat kenaikan kerja kompresor 45% dan penurunan COP 45%. Kata kunci : refrigerasi, kapal ikan, refrigeran R-22, refrigeran MC-22, kompresor, COP.
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Guney, Ezgi, and Okan Ozgonenel. "An Eco-Friendly Gas Insulated Transformer Design." Energies 14, no. 12 (2021): 3698. http://dx.doi.org/10.3390/en14123698.
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Electricity companies around the world are constantly seeking ways to provide electricity more safely and efficiently while reducing the negative impact on the environment. Mineral oils have been the most popular transformer insulation, having excellent electrical insulating properties, but have many problems such as high flammability, significant cleaning problems, and are toxic to fish and wildlife. This paper presents an alternative approach to mineral oil: a transformer design that is clean and provides better performance and environmental benefits. A 50 kVA, 34.5/0.4 kV gas insulated distribution transformer was designed and evaluated using the COMSOL Multiphysics environment. R410A was used as insulation material. R410A is a near-azeotropic mixture of difluoromethane (CH2F2, called R-32) and pentafluoro ethane (C2HF5, called R-125), which is used as a refrigerant in air conditioning applications. It has excellent properties including environmentally friendly, no-ozone depletion, low greenhouse effect, non-explosive and non-flammable, First, the breakdown voltage of the selected gas was determined. The electrostatic and thermal properties of the R410A gas insulated transformer were investigated in the COMSOL environment. The simulation results for the performance of oil and SF6 gas insulated transformers using the same model were compared. The gas-insulated transformer is believed to have equivalent performance and is an environmentally friendly alternative to current oil-based transformers.
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Say, Daniel, Anita L. Ganesan, Mark F. Lunt, et al. "Emissions of halocarbons from India inferred through atmospheric measurements." Atmospheric Chemistry and Physics 19, no. 15 (2019): 9865–85. http://dx.doi.org/10.5194/acp-19-9865-2019.
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Abstract. As the second most populous country and third fastest growing economy, India has emerged as a global economic power. As such, its emissions of greenhouse and ozone-depleting gases are of global significance. However, unlike neighbouring China, the Indian sub-continent is very poorly monitored by atmospheric measurement networks. India's halocarbon emissions, here defined as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs) and chlorocarbons, are not well-known. Previous measurements from the region have been obtained at observatories many hundreds of kilometres from source regions, or at high altitudes, limiting their value for the estimation of regional emission rates. Given the projected rapid growth in demand for refrigerants and solvents in India, emission estimates of these halocarbons are urgently needed to provide a benchmark against which future changes can be evaluated. In this study, we report atmospheric-measurement-derived halocarbon emissions from India. With the exception of dichloromethane, these top-down estimates are the first for India's halocarbons. Air samples were collected at low altitude during an aircraft campaign in June and July 2016, and emissions were derived from measurements of these samples using an inverse modelling framework. These results were evaluated to assess India's progress in phasing out ozone-depleting substances under the Montreal Protocol. India's combined CFC emissions are estimated to be 54 (27–86) Tg CO2 eq. yr−1 (5th and 95th confidence intervals are shown in parentheses). HCFC-22 emissions of 7.8 (6.0–9.9) Gg yr−1 are of similar magnitude to emissions of HFC-134a (8.2 (6.1–10.7) Gg yr−1). We estimate India's HFC-23 emissions to be 1.2 (0.9–1.5) Gg yr−1, and our results are consistent with resumed venting of HFC-23 by HCFC-22 manufacturers following the discontinuation of funding for abatement under the Clean Development Mechanism. We report small emissions of HFC-32 and HFC-143a and provide evidence to suggest that HFC-32 emissions were primarily due to fugitive emissions during manufacturing processes. A lack of significant correlation among HFC species and the small emissions derived for HFC-32 and HFC-143a indicate that in 2016, India's use of refrigerant blends R-410A, R-404A and R-507A was limited, despite extensive consumption elsewhere in the world. We also estimate emissions of the regulated chlorocarbons carbon tetrachloride and methyl chloroform from northern and central India to be 2.3 (1.5–3.4) and 0.07 (0.04–0.10) Gg yr−1 respectively. While the Montreal Protocol has been successful in reducing emissions of many ozone-depleting substances, growth in the global emission rates of the unregulated very short-lived substances poses an ongoing threat to the recovery of the ozone layer. Emissions of dichloromethane are found to be 96.5 (77.8–115.6) Gg yr−1, and our estimate suggests a 5-fold increase in emissions since the last estimate derived from atmospheric data in 2008. We estimate perchloroethene emissions from India and chloroform emissions from northern–central India to be 2.9 (2.5–3.3) and 32.2 (28.3–37.1) Gg yr−1 respectively. Given the rapid growth of India's economy and the likely increase in demand for halocarbons such as HFCs, the implementation of long-term atmospheric monitoring in the region is urgently required. Our results provide a benchmark against which future changes to India's halocarbon emissions may be evaluated.
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Faúndez, Claudio A., Richard A. Campusano, and José O. Valderrama. "Misleading results on the use of artificial neural networks for correlating and predicting properties of fluids. A case on the solubility of refrigerant R-32 in ionic liquids." Journal of Molecular Liquids 298 (January 2020): 112009. http://dx.doi.org/10.1016/j.molliq.2019.112009.
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Hsu, Chih-Neng, and Shih-Hao Wang. "Evaluating the Performance of Water Chillers Equipped with Constant- or Variable-Frequency Centrifugal Compressors." Processes 9, no. 6 (2021): 1039. http://dx.doi.org/10.3390/pr9061039.
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The cooling coefficient of performance (COPR) and energy efficiency ratio (EER) of refrigerant R-134a compressors (single- and double-compressors) with different refrigerant tonnage (200, 250, 300, 380, 500, and 700 RT) for centrifugal and Maglev centrifugal compressors change with different operating performance load percentages (10–100%), and constant-frequency and variable-frequency operation, resulting in performance differences. In particular, a water chiller can have a fixed cooling water inlet temperature of 32 °C and a variable cooling water inlet temperature between 18.33 °C and 32 °C. According to the actual test results, the commercial performance code program and parameter table of the water chiller were established. Based on the performance matching of different load chillers, the on-site load capacity was analyzed and the effective water chiller performance and model matching were determined as the best choice for the tonR number of the deicing machine and unit matching, providing a reference for a future large water chiller that cannot be used on site for a single unit tonR. To achieve energy-saving benefits, different types of compressors, different refrigeration tonR operation, constant-frequency unit and variable-frequency unit alternate operation, and different operating performance load percentage operation can be allocated. Finally, the results show that, when the cooling water inlet temperature is fixed, the Maglev variable-frequency centrifugal compressor water chiller is better than the constant-frequency centrifugal water chiller, and also better than the variable-frequency centrifugal water chiller. The larger the freezing tonR of the variable-frequency centrifugal water chiller, the smaller the difference between COPR and EER. When the cooling water inlet temperature changes, the Maglev variable-frequency centrifugal water chiller is better than the constant-frequency centrifugal water chiller, and it is also better than the variable-frequency centrifugal water chiller. The larger the freezing tonR of the variable-frequency centrifugal water chiller, the smaller the difference between COPR and EER. Moreover, the operating performance of the constant-frequency centrifugal water chiller is between 60% and 90%, which can maintain relatively high COPR and EER values. The operating performance of the variable-frequency centrifugal water chiller is between 40% and 70%, which can maintain relatively high COPR and EER values. Compared with the constant-frequency and variable-frequency, the Maglev variable-frequency centrifugal water chiller can maintain higher COPR and EER values when the operating performance is between 10% and 100%. When the operating performance is between 10% and 70%, it can maintain very high COPR and EER values. When the water chiller is selected in the field, the energy-saving of COPR and EER will be given priority. Therefore, the load capacity can be used to effectively manage the water chiller performance and model selection, so that the operation performance can reach the best percentage and energy saving can be achieved.
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Sigit Yulianto, Srihanto, Hariyanto, Bantu Hotsan S, and Dwi Yulianto. "Design of cold storage as a storage space for animal vaccines at PT. XYZ." JTTM : Jurnal Terapan Teknik Mesin 5, no. 2 (2024): 319–29. http://dx.doi.org/10.37373/jttm.v5i2.1212.
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A refrigeration system is a system used to cool a room or an industrial product in the food, pharmaceutical, beverage, vegetable, fruit, and other industries to maintain product quality. One of its uses is as storage for various kinds of pharmaceutical needs, including vaccines for both animals and humans. The problem with cold storage is that existing vaccine storage has been in operation for a long time so it is necessary to study whether it is still able to maintain the vaccine storage temperature, namely -80C. The aim of designing cold storage is to maintain a stable vaccine storage temperature. Because vaccines consist of various kinds of microorganisms that are easy to activate. To maintain the quality of the vaccine, cold storage is needed. The research methodology for writing this thesis is to collect design data from one of the vaccine storage industry companies, and literature studies, then analysis of cooling load planning studies, vaccine storage capacity in cold storage measuring 10 x 10 x m 3 meters and determine the power of the cooling machine using a system. standard vapor compression cooler. The results of the analysis of the refrigeration system planning study showed that the indoor vaccine capacity was 30,600 bottles or 2056,701 lbs (822,680 kg), storage temperature -80C, cooling load 308,133 Btu/hr, or 90,283 W, this system uses R 134 A refrigeration. Using refrigerant, power compressor 23.32 kW, or 32 HP, COP 3.9.
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Simmonds, Peter G., Matthew Rigby, Archie McCulloch, et al. "Changing trends and emissions of hydrochlorofluorocarbons (HCFCs) and their hydrofluorocarbon (HFCs) replacements." Atmospheric Chemistry and Physics 17, no. 7 (2017): 4641–55. http://dx.doi.org/10.5194/acp-17-4641-2017.
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Abstract. High-frequency, in situ global observations of HCFC-22 (CHClF2), HCFC-141b (CH3CCl2F), HCFC-142b (CH3CClF2) and HCFC-124 (CHClFCF3) and their main HFC replacements, HFC-134a (CH2FCF3), HFC-125 (CHF2CF3), HFC-143a (CH3CF3) and HFC-32 (CH2F2), have been used to determine their changing global growth rates and emissions in response to the Montreal Protocol and its recent amendments. Global mean mole fractions of HCFC-22, -141b, and -142b have increased throughout the observation period, reaching 234, 24.3 and 22.4 pmol mol−1, respectively, in 2015. HCFC-124 reached a maximum global mean mole fraction of 1.48 pmol mol−1 in 2007 and has since declined by 23 % to 1.14 pmol mol−1 in 2015. The HFCs all show increasing global mean mole fractions. In 2015 the global mean mole fractions (pmol mol−1) were 83.3 (HFC-134a), 18.4 (HFC-125), 17.7 (HFC-143a) and 10.5 (HFC-32). The 2007 adjustment to the Montreal Protocol required the accelerated phase-out of emissive uses of HCFCs with global production and consumption capped in 2013 to mitigate their environmental impact as both ozone-depleting substances and important greenhouse gases. We find that this change has coincided with a stabilisation, or moderate reduction, in global emissions of the four HCFCs with aggregated global emissions in 2015 of 449 ± 75 Gg yr−1, in CO2 equivalent units (CO2 eq.) 0.76 ± 0.1 Gt yr−1, compared with 483 ± 70 Gg yr−1 (0.82 ± 0.1 Gt yr−1 CO2 eq.) in 2010 (uncertainties are 1σ throughout this paper). About 79 % of the total HCFC atmospheric burden in 2015 is HCFC-22, where global emissions appear to have been relatively similar since 2011, in spite of the 2013 cap on emissive uses. We attribute this to a probable increase in production and consumption of HCFC-22 in Montreal Protocol Article 5 (developing) countries and the continuing release of HCFC-22 from the large banks which dominate HCFC global emissions. Conversely, the four HFCs all show increasing mole fraction growth rates with aggregated global HFC emissions of 327 ± 70 Gg yr−1 (0.65 ± 0.12 Gt yr−1 CO2 eq.) in 2015 compared to 240 ± 50 Gg yr−1 (0.47 ± 0.08 Gt yr−1 CO2 eq.) in 2010. We also note that emissions of HFC-125 and HFC-32 appear to have increased more rapidly averaged over the 5-year period 2011–2015, compared to 2006–2010. As noted by Lunt et al. (2015) this may reflect a change to refrigerant blends, such as R-410A, which contain HFC-32 and -125 as a 50 : 50 blend.
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Outcalt, Stephanie L., and Aaron J. Rowane. "Bubble Point Measurements of Three Binary Mixtures of Refrigerants: R-32/1234yf, R-32/1234ze(E), and R-1132a/1234yf." Journal of Chemical & Engineering Data 67, no. 4 (2022): 932–40. http://dx.doi.org/10.1021/acs.jced.1c00871.
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Sungkar, Faraj, Daniswara Krisna Prabatha, and Andrie Prasetyo. "Leading the Transition from Halogen Refrigerants to Natural Refrigerants in Indonesia (Pertamina Plaju Refinery as a Pioneer)." IOP Conference Series: Earth and Environmental Science 1395, no. 1 (2024): 012021. http://dx.doi.org/10.1088/1755-1315/1395/1/012021.
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Abstract Climate change has become a worldwide concern, prompting Indonesia to take ambitious actions to reduce emissions and control rising temperatures. The rapid growth of the Refrigeration and Air Conditioning (RAC) industry in Indonesia has led to higher greenhouse gas emissions. To tackle these environmental challenges, Pertamina Plaju Refinery is manufacturing natural refrigerants, specifically Musicool (Propane) and Breezone (Propylene), providing sustainable replacements for R-22 and R-32. Pertamina Plaju Refinery has made several process modifications and optimizations to support the production of Musicool and Breezone in the Alkylation and Purification Units. These modifications involve optimizing operating conditions and implementing necessary infrastructure changes. In general, Pertamina’s natural refrigerants consume 20-30% less energy than halogen refrigerants while offering similar cooling capacity to R-22 and R-32. Propane and Propylene-based refrigerants have the lowest impact on global warming and are eco-friendly due to their easy degradation process. Musicool and Breezone, having an ODP of 0.0, with maximum GWP of 3.3, indicating minimal contribution to ozone depletion. Pertamina’s efforts to engage and reach potential customers on these natural refrigerants, involve collaborative efforts among various organizations, including with all District Office Plaju, South Sumatra.
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Čaja, Alexander, Nikola Čajová Kantová, Andrej Kapjor, and Martin Vantúch. "Comparison of Performance Parameters of Four Types of Refrigerants." MATEC Web of Conferences 369 (2022): 04007. http://dx.doi.org/10.1051/matecconf/202236904007.
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The use of refrigerants requires to meet ecology and legislation requirements. The aim of the legislation is also to reduce the global warming potential (GWP). Natural refrigerants such as carbon dioxide, ammonia, and hydrocarbons such as propane, isobutene, and propylene are used mainly because of their environmental benefits compared to synthetic refrigerants. This work compares two natural refrigerants: R-744 and R-290 and two synthetic refrigerants: R-134a and R-32. All these refrigerants are used mainly in heat pumps. In this work were calculated and compared the following performance parameters: heat rejected in the condenser, cooling power, compressor power, and the coefficient of performance (COP). The most important parameter is the coefficient of performance because when it decreases, electric energy consumption increases. It requires reaching a high value of COP. Further, this work deals with the economic analyses of selected refrigerants. The last aim of this article is their ecologic analysis based on the GWP factor.
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Shon, Byung Hoon, Seung Won Jeon, Yongchan Kim, and Yong Tae Kang. "Review: Condensation and Evaporation Characteristics of Low GWP Refrigerants in Plate Heat Exchangers." International Journal of Air-Conditioning and Refrigeration 24, no. 02 (2016): 1630004. http://dx.doi.org/10.1142/s2010132516300044.
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In this paper, condensation and evaporation characteristics of low global warming potential (GWP) refrigerants such as R-1234yf and R-1234ze series are reviewed. This review focuses on heat transfer and pressure drop in plate heat exchangers. Mass flux is considered as an important factor while saturation temperature is not for condensation and evaporation process in plate heat exchangers. The dryout phenomenon occurs occasionally and gives greatly harmful impact on evaporation heat transfer. It is found that R-1234yf and R-1234ze(E) give slightly lower heat transfer performance than R-134a for both condensation and evaporation processes. Generally, low GWP refrigerants presented in this review give lower heat transfer coefficient and higher frictional pressure drop than the conventional refrigerants. Nevertheless, R-1234ze(Z) gives superior heat transfer performance than other refrigerants in condensation. R-32 gives remarkable performance in evaporation, but it gives relatively high GWP compared to other low GWP refrigerants.
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Chen, Jiufa, and Horst Kruse. "Concentration Shift Simulation for the Mixed Refrigerants R-404A, R-32/134a, and R-407C in an Air Conditioning System." HVAC&R Research 3, no. 2 (1997): 149–57. http://dx.doi.org/10.1080/10789669.1997.10391368.
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Holcomb, Cynthia D., Vicki G. Niesen, Lambert J. Van Poolen, and Stephanie L. Outcalt. "Coexisting densities, vapor pressures and critical densities of refrigerants R-32 and R-152a, at 300-385 K." Fluid Phase Equilibria 91, no. 1 (1993): 145–57. http://dx.doi.org/10.1016/0378-3812(93)85085-z.
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Shen, Bo, and Moonis R. Ally. "Comparative Performance of Low Global Warming Potential (GWP) Refrigerants as Replacement for R-410A in a Regular 2-Speed Heat Pump for Sustainable Cooling." Sustainability 13, no. 15 (2021): 8199. http://dx.doi.org/10.3390/su13158199.
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Heat pumps are currently being developed to reduce the energy footprint for residential and commercial building space conditioning and water heating loads in cold climates. To mitigate the nocuous impact of greenhouse gas emissions on the environment, and to create a carbon-neutral building stock, alternate lower-GWP refrigerants must also replace the predominant use of R-410A, without re-engineering the mechanical hardware. In this paper, we analyze the performance of lower-GWP alternative refrigerants (R-32, R-452B, R-454B, and R-466A) relative to the conventional R-410A and draw conclusions on the relative performances to meet cooling loads. The simulations are accomplished using the heat pump design model, a well-known, public-domain design tool with a free web interface and downloadable desktop version to support public use and the HVAC R&D community. The contributions contain detailed, hardware-based heat exchanger and system analyses to provide a comprehensive assessment. The results of the simulation are scrutinized from the first (capacity and energy efficiency) and second laws (exergy analysis) to identify sources of systemic inefficiency, the root cause of lost work. This rigorous approach provides an exhaustive analysis of alternate lower-GWP refrigerants to replace R-410A using the same hardware. The results have practical value in engineering heat pumps in an economy that is compelled to alter by the consequences and uncertainties of climate change, to reduce its anthropogenic carbon footprint.
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Perangin-angin, Siwan Ediamanta, Himsar Ambarita, Waldemar Naibaho, Parulian Siagian, Marhiras Sitanggang, and Libianko Sianturi. "Perbandingan Performansi 4 Variasi Siklus Kompresi Uap 2 Tingkat." SPROCKET JOURNAL OF MECHANICAL ENGINEERING 2, no. 1 (2020): 1–7. http://dx.doi.org/10.36655/sproket.v2i1.311.
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Keberadaan Pengkondisan Udara (AC) tidak terlepas dari aspek kehidupan sehari-hari. Pengkondisian Udara memanfaatkan prinsip termodinamika siklus kompresi uap. COP merupakan parameter untuk melihat kinerja dari mesin pendingin tersebut. Dalam penelitian ini, salah satu cara untuk meningkatkan COP dari mesin Pendingin adalah memodifikasi siklus 1 tingkat menjadi siklus 2 tingkat. Karya inimengkaji perbandingan model siklus kompresi uap 2 tingkat dengan beberapa variasi. Perbandingan ini menggunakan sofware ASPEN PLUS V10 untuk melihat performansi dari setiap varian. Untuk fluida kerja (Refrigeran) yang digunakan adalah R-32. Dari hasil simulasi Varian no III menunjukkan nilai COP yang lebih tinggi dari pada varian lainnya.
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Kim, Nae-Hyun, Hyung-Ho Gook, and Byung-Moo Lee. "Condensation Heat Transfer and Pressure Drop of R-404A in 7.0 mm O.D. Smooth and Microfin Tube at Low Mass Fluxes." International Journal of Air-Conditioning and Refrigeration 26, no. 01 (2018): 1850005. http://dx.doi.org/10.1142/s2010132518500050.
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R-404A condensation heat transfer and pressure drop data are provided for 7.0[Formula: see text]mm O.D. smooth and microfin tubes. Tests were conducted for a range of mass fluxes (from 80 to 200[Formula: see text]kg/m2s) and quality (from 0.2 to 0.8). The heat flux was 6[Formula: see text]kW/m2 and saturation temperature was 45[Formula: see text]C. It was found that both the heat transfer enhancement factor and the pressure drop penalty factor increase as mass flux increases. The range of pressure drop penalty factor (0.99–1.27) was smaller than that of heat transfer enhancement factor (1.21–1.96). Smooth tube heat transfer coefficients and pressure drops are reasonably predicted by Shah [An improved and extended general correlation for heat transfer during condensation in plain tubes, Int. J. HVAC&R Res. 15 (2009) 889–913] and Jung and Radermacher [Prediction of pressure drop during horizontal annular flow boiling of pure and mixed refrigerants, Int. J. Heat Mass Transfer 32 (1989) 2435–2446] correlation, respectively. For the microfin tube, however, all the existing correlations do not adequately predict the present data. Poor predictions may be attributed to the lack of R-404A and low mass flux data in their database.
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Ufie, Rikhard. "KAJI EKSPERIMENTAL PEMANFAATAN KALOR BUANGAN KONDENSOR UNTUK KEBUTUHAN PENGERINGAN." ALE Proceeding 1 (July 18, 2021): 102–7. http://dx.doi.org/10.30598/ale.1.2018.102-107.
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Abstrak Kaji eksperimental pemanfaatan kalor buangan kondensor untuk kebutuhan pengeringan telah diteliti. Proses pendinginan dengan mesin refrigerasi siklus uap dimana kalor yang masuk ke sistem berasal dari beban pendinginan ditambah kalor hasil kerja kompresi dari kompresor biasanya dibuang ke lingkungan. Penelitian ini akan mengkaji kemungkinan pemanfaatan kalor yang dibuang ke lingkungan tersebut dengan cara pengembangan prototipe pendinginan dan pengeringan terpadu. Selain itu diharapkan akan diperoleh efek pendinginan bagi produk tertentu melalui kerja evaporator dan efek pengeringan melalui kerja kondensor. Unit pendinginan dan pengeringan terpadu menggunakan Freon R-22 dengan daya kompresor 0.5 hp (0.368 kW) dengan produk pendinginan yakni massa air 32 kg. Hasil penelitian memperlihatkan pada temperatur kondensasi 48.3 oC diperoleh temperatur lemari pengering rata-rata 37.8 oC dengan kapasitas pemanasan 914.6 W yaitu dimana ratio kompresi 6.98 dengan tekanan evaporasi 38.6 psia dan temperatur evaporasi -18.5 oC. Pada beban kerja sebesar 613.057 W diperoleh daya kompresi terpakai 307.6 W dengan COP sebesar 1.99, sedangkan laju kalor yang dilepas kondensor sebesar 920.72 W.
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Grosshandler, W. L., M. K. Donnelly, and C. Womeldorf. "Flammability Measurements of Difluoromethane." Journal of Heat Transfer 122, no. 1 (1999): 92–98. http://dx.doi.org/10.1115/1.521440.
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Difluoromethane (CH2F2, or R-32) is a candidate to replace ozone-depleting chlorofluorocarbon refrigerants. Because CH2F2 is flammable, it is necessary to assess the hazard posed by a leak in a refrigeration machine. The currently accepted method for determining flammability, ASTM E 681 has difficulty discerning the flammability boundary for weak fuels such as CH2F2. This article describes an alternative approach to identify the limits of flammability, using a twin, premixed counterflow flame. By using the extinction of an already established flame, the point dividing flammable from nonflammable becomes unambiguous. The limiting extinction mixture changes with stretch rate, so it is convenient to report the flammability limit as the value extrapolated to a zero stretch condition. In the burner, contoured nozzles with outlet diameters of 12 mm are aligned counter to each other and spaced 12 mm apart. The lean flammability limit of CH2F2 in dry air at room temperature was previously reported by the authors to be a mole fraction of 0.14, using the twin counterflow flame method. In the current study, relative humidity was not found to affect the lean limit. Increasing the temperature of the premixed fuel and air to 100°C is shown to extend the flammability limit in the lean direction to 0.13. The rich limit of CH2F2 found using the counterflow method is around 0.27. The uncertainties of the measurements are presented and the results compared to data in the literature. [S0022-1481(00)02501-9]
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Trihartanto, Arif, and Ketut Gunawan. "Pembuatan Trainer AC Split Sebagai Media Praktikum Pada Laboratorium Teknik Pendingin Undiksha." Jurnal Pendidikan Teknik Mesin Undiksha 10, no. 1 (2022): 20–27. http://dx.doi.org/10.23887/jptm.v10i1.42863.
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Penelitian ini merupakan pengembangan media praktikum berupa trainer AC split untuk memenuhi kegiatan praktikum teknik pendingin di Program Studi Pendidikan Teknik Mesin Undiksha. Tujuan penelitian ini adalah untuk menghasilkan media praktikum yang memiliki kualitas baik dan layak digunakan. Kegiatan diawali dengan perancangan trainer AC yang kemudian diimplementasikan pada mahasiswa. Jenis penelitian yang digunakan adalah penelitian research and development (R&D) model pembelajaran Lee & Owens. Sampel penelitian ini menggunakan kelompok kecil dengan jumlah mahasiswa sebanyak 6 orang konsentrasi teknik pendingin. Penilaian media praktikum trainer AC split dilakukan oleh ahli materi, ahli media, serta mahasiswa. Dari validasi dua ahli materi memperoleh skor rata-rata 52,5 atau 87,5%. Validasi ahli dua ahli media memperoleh skor rata-rata 53 atau 88,33%, dan ujicoba mahasiswa memperoleh skor rata-rata 296 atau 89,70% dengan kategori semua skor tersebut adalah sangat layak. Sehingga dapat disimpulkan bahwa media praktikum trainer AC split ini dapat diterima oleh mahasiswa dengan kriteria sangat layak untuk digunakan. Kata kunci: media praktikum; trainer AC split This research is the development of practicum media in the form of a split AC trainer to fulfill refrigeration engineering practicum activities in the Undiksha Mechanical Engineering Education Study Program. The purpose of this research is to produce practicum media that have good quality and are suitable for use. The activity begins with the design of an AC trainer which is then implemented on students. The type of research used is research and development (R&D) Lee & Owens learning model. The sample of this study used a small group with a total of 6 students concentrating on cooling techniques. The assessment of the AC split trainer practicum media was carried out by material experts, media experts, and students. From the validation of two material experts obtained an average score of 52.5 or 87.5%. Expert validation of two media experts obtained an average score of 53 or 88.33%, and student trials obtained an average score of 296 or 89.70% with the category of all scores being very feasible. So it can be concluded that the AC split trainer practicum media can be accepted by students with very feasible criteria for use.Keywords : practicum media; split AC trainerAkbar, S. (2013). Instrumen Perangkat Pembelajaran. Bandung: PT. Remaja Rosda Karya.Akbar, Taufiq Nuril. (2016). Pengembangan Multimedia Interaktif IPA Berorientasi Guided Inquiry Pada Materi Sistem Pernapasan Manusia Kelas V SDN Kebonsari 3 Malang. Jurnal Pendidikan: Teori, Penelitian, dan Pengembangan Volume: 1 No. 6 Halaman: 1120 – 1126.Al Idrus, S. W., Purwoko, A. A., Hadisaputra, S., & Junaidi, E. (2020). Pengembangan Modul Praktikum Kimia Lingkungan Berbasis Green Chemistry Pada Mata Kuliah Kimia Lngkungan. Jurnal Pijar Mipa, 15(5), 541–547. https://doi.org/10.29303/jpm.v15i5.2171Bengi, N. I. (2021). Tahapan-Tahapan Dalam Proses Pengembangan Koleksi. Jurnal Adabiya, 23(1), 1–19.Diks, M E. (2002). Pengetahuan Praktis Teknik Pendingin Dan Reparasinya. Jakarta: PT Bumi AksaraElisa, Edi., dkk. (2021). Pengembangan Laboratorium Virtual Kimia Teknik untuk Meningkatkan Keterampilan Berpikir Kritis dan Proses Sains Mahasiswa. Journal of The Indonesian Society of Integrated Chemistry, 12(2), 55-61. https://doi.org/10.22437/jisic.v12i2.11243Mustabsyirah. (2017). Pengembangan Media Pembelajaran Praktikum Biologi Berbasis Video Pada Materi Sistem Pencernaan Di Kelas XI IPA MAN 2 Sinjai Utara Kabupaten Sinjai. [Skripsi]. Makasar: Universitas Islam Negeri Alauddin.Nursusanto, Usman. (2016). Pengembangan AC Trainer Sebagai Media Pembelajaran Sistem Instalasi Tata Udara Siswa Kelas XI SMK N 1 Magelang. [Skripsi]. Yogyakarta: Universitas Negeri Yogyakarta.Primayudi, I.B.K.K. (2019). Pengembangan Media Pembelajaran Materi Sistem Kemudi Dan Power Steering Menggunakan Autoplay Media Studio. [Skripsi]. Singaraja: Universitas Pendidikan Ganesha.Sadiman, Arif S., dkk. (2005). Media Pendidikan (Pengertian, Pengembangan, dan Pemanfaatan) : Jakarta: PT Jakarta GravindoSetyawan, Totok. (2020). Pengembangan Alat Peraga Lemari Pendingin Sebagai Media Pembelajaran Pada Mata Kuliah Perancangan Sistem Refrigerasi. [Skripsi]. Singaraja: Universitas Pendidikan GaneshaSatria, A., & Yuhendri, M. (2021). Analisis Kelengkapan Peralatan Praktek Dasar Listrik Elektronika di SMK. Jurnal Pendidikan Teknik Elektro, 02(01), 32–36. http://jpte.ppj.unp.ac.id/index.php/JPTE/article/view/66Simatupang, A. C., & Sitompul, A. F. (2018). Analisis Sarana Dan Prasarana Laboratorium Biologi Dan Pelaksanaan Kegiatan Praktikum Biologi Dalam Mendukung Pembelajaran Biologi Kelas Xi. Jurnal Pelita Pendidikan, 6(2), 109–115. https://doi.org/10.24114/jpp.v6i2.1014Wibawa, I. G. P., Ratnaya, I. G., & Santiyadnya, N. (2020). Pengembangan Media Pembelajaran Air Conditioner ( Ac ) Split Pada Mata Kuliah Teknik Pendingin. Jurnal Pendidikan Teknik Elektro Undiksha, 9(1), 1–9. https://doi.org/http://dx.doi.org/10.23887/jjpte.v9i1.23652