• 설비공학논문집
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• 제14권9호
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• pp.706-716
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• 2002

R410A and R407C are considered to be alternative refrigerants to R22 for the air-conditioners. Experimental investigation is made to study the condensation heat transfer characteristics of slit fin-tube heat exchanger using alternative refrigerants R410A and R407C. R407C, a non-azeotropic refrigerant mixture, exhibited a quite different condensation phenomenon from those of R22 and R410A and its condensation heat transfer coefficient was much lower than that of R22 and R410A. Between the R22 and R410A, the condensation heat transfer coefficient of R410A, near-azeotropic refrigerant mixture, was a little higher than that of R22. R410A also showed the lowest condensation pressure drop across the test section. For all refrigerants, the condensation heat transfer coefficient and pressure drop increase as the mass flux increases.

• International Journal of Air-Conditioning and Refrigeration
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• 제11권4호
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• pp.188-198
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• 2003

R410A and R407C are considered to be alternative refrigerants of R22 for the air-conditioners. An experimental study is carried out to investigate the effect of the change of mass flow rate on the characteristics of heat transfer and pressure drop in three row slit finned-tube heat exchanger for R407C, R410A and R22. R407C, a non-azeotropic refrigerant mixture, exhibited a quite different condensation phenomenon from those of R22 and R410A and its condensation heat transfer coefficient was much lower than that of R22 and R410A. On the other hand, the condensation heat transfer coefficient of R410A, near-azeotropic refrigerant mixture, was a little higher than that of R22. R410A also showed the lowest condensation pressure drop across the test section. For all refrigerants, the condensation heat transfer coefficient and pressure drop increase as the mass flux increases. The condensation heat transfer coefficient correlation proposed by Kedzierski shows the best agreement with the experimental data within $\pm$20%.

• 설비공학논문집
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• 제12권6호
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• pp.589-598
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• 2000

The vapor-liquid equilibrium and miscibility measurement apparatus was developed and used to obtain data for refrigerant/oil mixture. The vapor-liquid equilibrium and miscibility data for R-410a/POE32 and R-410A/POE46 oil mixtures are obtained over the temperature range from -20 to $60^{\circ}C\;with\;10^{\circ}C$ intervals and the oil concentration range from 0 to 90 wt%. Using the experimental data, an empirical model is developed to predict the temperature-pressure-concentration relations for R-410A/POE oil mixtures at equilibrium. In the R-410A/POE32 oil mixture, the average root-mean-square deviation between measured data and calculated results from the empirical model is 2.00% and in the R-410a/POE46 oil mixture, that is 3.69%. Flory-Huggins theory is also used to predict refrigerant/oil mixture behavior. Miscibility for R-410A/POE32 oil mixture was observed all over the experimental conditions. Immiscibility for R-410A/POE46 oil mixture was observed at the low oil concentrations(10~30 wt%).

• 한국산학기술학회논문지
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• 제14권4호
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• pp.1548-1554
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• 2013

본 논문은 R744-R410A용 이원 냉동시스템의 작동변수에 대한 기초 설계자료를 제공하고자 이원 냉동시스템의 성능 특성을 분석한 것이다. 이원 냉동시스템의 성능은 EES 프로그램을 이용하여 분석하였다. 작동변수로는 R410A용 고온사이클과 R744용 저온사이클의 압축기효율, 응축과 증발온도이다. 이원 냉동사이클의 응축온도가 감소할수록 이원 냉동사이클의 COP는 증가하며, 증발온도가 증가할수록 COP가 증가함을 알 수 있다. 또한, 이원 냉동사이클의 압축효율이 증가할수록 COP가 증가한다. 그러므로 압축효율, 증발온도, 응축온도 등의 인자들이 R410A와 R744용 이원 냉동사이클의 COP에 영향을 주는 것을 알 수 있다. 그리고 이 이원 냉동사이클은 각각의 변수들에서 최고 효율을 가지는 캐스케이드 증발온도가 존재함을 알 수 있다. 따라서 이러한 인자들을 고려하여 R410A와 R744용 이원 냉동사이클을 설계하는 것은 중요하다.

• 설비공학논문집
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• 제11권4호
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• pp.537-541
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• 1999

The system performance of a room air conditioner using R410A was experimentally evaluated and compared with that of R22 system. The results indicated that the cooling EER(energy efficiency ratio) of R410A was 1% higher than that of R22 at the outdoor temperature of $35^{\circ}C$. As outdoor temperature increases above $35^{\circ}C$ ambient, EER of the R410A system decreased more substantially compared with R22 system. R410A showed higher compressor discharge temperature than that of R22 system at the outdoor temperature of higher than $50^{\circ}C$.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2009년도 추계학술발표논문집
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• pp.889-892
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• 2009

본 연구에서는 R-22와 R-410A를 사용하는 냉난방기의 성능 및 사이클 특성을 조사하기 위하여, R-22와 R-410A를 적용한 냉난방기의 성능을 비교 실험하였다. 이를 위하여 R-22와 R-410A 냉난방기 사이클을 구성하였으며, 냉난방기 시스템의의 성능을 측정하기 위하여 공기엔탈피식 칼로리미터를 사용하였다. 실험을 통해 냉난방 온도조건에서 능력, 소비전력, 온도, 압력 등을 측정하였다. 본 연구결과는 R-410A의 냉난방기 사이클 적용 가능성을 보여주었다. 한편, 실험으로부터 획득된 데이터는 R-410A 냉난방기 개발시 기초 설계자료 및 시스템의 효율향상을 위한 방안으로 활용될 것이다.

• 설비공학논문집
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• 제15권12호
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• pp.1049-1059
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• 2003

R410A is considered as an alternative refrigerant to R22 for air conditioners. An experimental investigation was made to study the characteristics of the heat transfer and pressure drop for R410A flowing in a fin-and-tube heat exchanger used for commercial air-conditioning units. Experiments were carried out under the conditions of inlet refrigerant temperature of 6$0^{\circ}C$ and refrigerant mass flux varying from 150 to 250 kg/$m^2$s for refrigerant side. The inlet air has dry bulb temperature of 35$^{\circ}C$, relative humidity of 40% and air velocity varying from 0.68 to 1.6 m/s. Experiments show that air velocity decreased by 16% is needed for R410A than that of R22 for subcooling temperature of 5$^{\circ}C$, which resulted in air-side pressure drop decrease of 15% for R410A as compared to R22. As a consequence, in order to provide the same design condition of a condenser, the fan requires lower electric-power consumption with R410A than that with R22.

• 한국수소및신에너지학회논문집
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• 제33권4호
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• pp.413-418
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• 2022

This paper presents two-phase condensation heat transfer and pressure drop characteristics of R32 and R454B as an alternative refrigerant to R410A in a 9.52 mm OD microfin tube. The test facility has a straight, horizontal test section with an active length of 2.0 m and is cooled by cold water circulated in a surrounding annular space. The heat transfer coefficients of the annular space were obtained using the modified Wilson plot method. Average condensation heat transfer coefficient and pressure drop data are presented at the condensation temperature of 35℃ for the range of mass flux 100-400 kg/m²s. The average condensation heat transfer coefficients of R32 refrigerant are 35-47% higher than R410A at the mass flux considered in the study, while R454B data are similar to R410A. The average pressure drop of R32 and R454B are much higher than R410A and they are 134-224% and 151-215% of R410A, respectively. R32 and R454B have relatively low GWP and high heat transfer characteristics, so they are suitable as alternatives for R410A.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1997년도 추계학술발표회 논문집
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• pp.85-92
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• 1997

R22 대체냉매로 R410A를 사용하는 가정용 분리형 에어컨의 성능을 향상시키기 위한 연구를 실험적으로 수행하였다. R22 시스템에서 냉매와 압축기의 오일만 교체할 경우 기본시스템에 비해 냉방능력은 17% 증가하였고 에너지 소비효율은 29% 감소하였다. 이를 해결하기 위해 고압냉매 R410A에 적합한 압축기와 시스템의 효율을 향상시키기 위한 고효율 응축기를 개발하였다. R410A 압축기와 고효율 응축기를 R410A 시스템에 적용할 경우 냉방능력과 효율이 R22 시스템에 비해 각각 1.8% 와 2.2% 증가하였으며, 소음도 R22 시스템과 동등한 수준을 나타내었다.

• 설비공학논문집
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• 제13권12호
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• pp.1245-1254
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• 2001

For a R410A-rolling piston type rotary compressor model which was modified by reducing the cylinder height and shaft eccentricity from R22-compressor version, numerical simulation has been carried out and simulation results have been found to be compared fairly well with those of measurements. EER of this first version of R410A compressor was 4.8% lower than that of R22 compressor. To improve the performance of the R410A compressor model, parametric study on the design parameters related to the discharge port system has been performed by using the numerical simulation program, and optimum conditions for the highest EER have been obtained with the aid of Taguchi method. With the optimized discharge port configuration, EER has been improved by 1.7%.