Influence of Nano-Refrigeration-Oil on Saturated Vapor Pressure of R22

2011 ◽  
Vol 694 ◽  
pp. 309-314 ◽  
Author(s):  
Jiang Feng Lou ◽  
Rui Xiang Wang ◽  
Min Zhang
Keyword(s):  
Experimental Data ◽  
Vapor Pressure ◽  
Mass Fraction ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Experimental Results ◽  
Vapor Pressures ◽  
Temperature Range ◽  
Mass Fractions

The saturated vapor pressures of R22 uniformly mixed with refrigeration oil and nano- refrigeration-oil were measured experimentally at a temperature range from 263 to 333K and mass fractions from 1 to 5%. The experimental results showed that the saturated vapor pressure of R22/KT56 mixture was lower than that of pure R22; the pressure deviation between them increased with a raising mass fraction of refrigeration oil and temperature. After adding nano-NiFe2O4 and nano-fullerene into KT56, the pressure deviation increased at the same mass fraction and temperature. A saturated vapor pressure correlation for R22 and refrigeration oil/nano-refrigeration-oil mixture was proposed, and the calculated values agreed with the experimental data within the deviation of ± 0.77%.

scholarly journals The relationship between the surface tension and the saturated vapor pressure of model nanofluids

2019 ◽  
Vol 55 (1) ◽  
pp. 40-46
Author(s):  
O. Ya. Khliyeva ◽  
D. A. Ivchenko ◽  
K. Yu. Khanchych ◽  
I. V. Motovoy ◽  
V. P. Zhelezny
Keyword(s):  
Surface Tension ◽  
Surface Layer ◽  
Vapor Pressure ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Practical Interest ◽  
Al2o3 Nanoparticles ◽  
Temperature Range ◽  
Specific Intermolecular Interaction ◽  
The Relationship

Information on surface tension is necessary for modeling boiling processes in nanofluids. It was shown that the problem of predicting the surface tension of complex thermodynamic systems, such as nanofluids, remains outstanding. It should be noted that the surface tension of liquids and the saturated vapor pressure are due to a specific intermolecular interaction in the region of spatial heterogeneity of the substance (surface layer). Moreover, the compositions of the surface layer of nanofluid and its liquid phase are not equal. The presence of nanoparticles in the base fluid affects the composition of the surface layer of liquids. However, there are no methods for determining the composition of the surface layer of nanofluids and this fact complicates establishing the dependence of the surface tension on the state parameters of nanofluids. It should be mentioned that the number of possible methodological errors in measurements of the saturated vapor pressure of nanofluids is significantly lower than for the surface tension measurements. Therefore, in the development of models for predicting the surface tension, scientific and practical interest has establishing the relationship between the surface tension and the saturated vapor pressure of nanofluids. In the presented work, we consider the nanofluids of isopropanol/Al2O3 nanoparticles and o-xylene/fullerenes C60. Saturated vapor pressure and surface tension of nanofluids of isopropanol/Al2O3 nanoparticles have been studied in the temperature range 293 – 363 K and concentrations of Al2O3 nanoparticles 0-8.71 g/kg. Measurement of saturated vapor pressure and surface tension of nanofluids of o-xylene/fullerenes C60 have been performed in the temperature range 283 – 348 K and the concentration of C60 0-7.5 g/kg. It is shown that additives of Al2O3  nanoparticles and fullerenes C60 lead to a decrease in the surface tension and increase in the saturated vapor pressure. It is shown that there is a universal dependence between the reduced surface tension and saturated vapor pressure for the researched nanofluids.

Pyrolytic properties of di-n-butyltin(IV) diacetate as a precursor for sprayed SnO2 thin films

1994 ◽  
Vol 9 (3) ◽  
pp. 663-668 ◽  
Author(s):  
Isao Yagi ◽  
Eiichiro Ikeda ◽  
Yasuo Kuniya
Keyword(s):  
Thin Films ◽  
Vapor Pressure ◽  
Spray Pyrolysis ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Chemical Species ◽  
Crystal Phase ◽  
Temperature Range ◽  
Sno2 Thin Films ◽  
Two Stages

The saturated vapor pressure and pyrolytic properties of di-n-butyltin(IV) diacetate have been investigated with and without oxygen in order to understand the orientational growth of SnO2 thin films by spray pyrolysis. The dependence of the saturated vapor pressure on temperature was determined: log P(evap.)Torr = −2.827 × 103/T + 7.687. It has been found that the pyrolysis of this compound consisted of two stages: elimination of the n-butyl groups in a temperature range between about 280°and 310 °C, and of the acetoxy groups above 320 °C. Such decompositions were shifted toward lower temperatures under oxygen. It was also found that oxygen in air in addition to intramolecular oxygen contributed to the formation of SnO2 crystal phase. Moreover, it was suggested that pyrolized chemical species preserving the Sn-O bond probably related the orientational growth of the (200) plane of sprayed SnO2 thin films.

scholarly journals Vapor Pressure of Saturated Aqueous Solutions of Potassium Sulfate from 310 K to 345 K

2011 ◽  
Vol 2011 ◽  
pp. 1-4 ◽  
Author(s):  
Matias O. Maggiolo ◽  
Francisco J. Passamonti ◽  
Abel C. Chialvo
Keyword(s):  
Experimental Data ◽  
Vapor Pressure ◽  
Aqueous Solutions ◽  
Water Activity ◽  
Experimental Evaluation ◽  
Experimental Results ◽  
Potassium Sulfate ◽  
Temperature Range ◽  
Analytical Expressions

The experimental evaluation of the vapor pressure of saturated aqueous solutions of potassium sulfate was carried out in the range of temperatures 310 K≤T≤345 K. The experimental data were used to determine the corresponding values of the water activity in such solutions. The analytical expressions as a function of temperature of both, vapor pressure and water activity, were obtained from the correlation of the experimental results. The vapor pressure expression was also extrapolated to a different temperature range in order to make a comparison with the results obtained by other authors.

scholarly journals Investigation of applicability of Peng–Robinson and GERG-2008 equations of state of real gas for calculating properties of Freons for refrigeration machines and compressors

2021 ◽  
Vol 5 (1) ◽  
pp. 34-43
Author(s):  
M. I. Sokolov ◽  
◽  
Yu. V. Kozhukhov ◽  
Keyword(s):  
Experimental Data ◽  
Vapor Pressure ◽  
Mathematical Modelling ◽  
Equations Of State ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Saturation Pressure ◽  
State Equations ◽  
Real Gas ◽  
Enthalpy And Entropy

A study of real gas state equations Peng–Robinson and GERG-2008 with respect to calculation of Freons R404A, R408A and R410A has been carried out. Four Freon parameters are calculated during the study: saturated vapor pressure at the saturation line at some Freon temperature, Freon density at saturation pressure and some temperature, enthalpy and entropy at the same pressures and temperature. The data obtained from the calculation of Freon by the above equations are compared with the experimental data for each of the above Freons. As a result of this work, data have been obtained to evaluate the accuracy of the Peng–Robinson and GERG-2008 equations of state for each of the three CFCs, to evaluate the effectiveness of these equations, and to provide recommendations for the calculation and application of these equations in the design and mathematical modelling of refrigeration machines

scholarly journals Effects of nanoparticles on hydraulic cavitation

2018 ◽  
Vol 240 ◽  
pp. 03004
Author(s):  
Min-rui Chen ◽  
Jin-yuan Qian ◽  
Zan Wu ◽  
Chen Yang ◽  
Zhi-jiang Jin ◽  
...  
Keyword(s):  
Vapor Pressure ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Geometric Model ◽  
Pressure Ratio ◽  
Perforated Plate ◽  
Significant Parameter ◽  
Operation Conditions ◽  
Small Bubbles ◽  
Crucial Condition

When liquids flowing through a throttling element, such as a perforated plate, the velocity increases and the pressure decreases. If the pressure is below the saturated vapor pressure, the liquid will vaporize into small bubbles, which is called hydraulic cavitation. In fact, vaporization nucleus is another crucial condition for vaporizing. The nanoparticles contained in the nanofluids play a significant role in vaporization of liquids. In this paper, the effects of the nanoparticles on hydraulic cavitation are investigated. Firstly, a geometric model of a pipe channel equipped with a perforated plate is established. Then with different nanoparticle volume fractions and diameters, the nanofluids flowing through the channel is numerically simulated based on a validated numerical method. The operation conditions, such as the temperature and the pressure ratio of inlet to outlet, are the considered variables. As a significant parameter, cavitation numbers under different operation conditions are achieved to investigate the effects of nanoparticles on hydraulic cavitation. Meanwhile, the contours are extracted to research the distribution of bubbles for further investigation. This study is of interests for researchers working on hydraulic cavitation or nanofluids.

Porous Hydroxyapatite with Tailored Crystal Surface Prepared by Hydrothermal Method

2005 ◽  
Vol 284-286 ◽  
pp. 353-356 ◽  
Author(s):  
Koji Ioku ◽  
Giichiro Kawachi ◽  
Nakamichi Yamasaki ◽  
Hirotaka Fujimori ◽  
Seishi Goto
Keyword(s):  
Aspect Ratio ◽  
Vapor Pressure ◽  
Hydrothermal Method ◽  
Saturated Vapor Pressure ◽  
Crystal Surface ◽  
Saturated Vapor ◽  
Pure Water ◽  
Porous Hydroxyapatite ◽  
Exposure Method ◽  
The Mean

Porous plates of hydroxyapatite (Ca10(PO4)6(OH)2; HA) with about 0.5 to 5 mm in thickness and porous HA granules of about 40 µm to 1 mm in size with tailored crystal surface were prepared by the hydrothermal vapor exposure method at the temperatures above 105 °C under saturated vapor pressure of pure water. Porous HA plates with about 75 % porosity prepared at 120 °C were composed of rod-shaped crystals of about 20 µm in length. Porous HA granules prepared at 160 °C were also composed of rod-shaped crystals of about 20 µm in length with the mean aspect ratio of 30. These crystals were elongated along the c-axis. Rod-shaped HA crystals were locked together to make micro-pores of about 0.1 to 0.5 µm in size. Both of materials were nonstoichiometric HA with calcium deficient composition. These materials must have the advantage of adsorptive activity, because they had large specific crystal surface and much micro-pores.

scholarly journals Application of a Micro-Flow Regulating Valve in Saturated Vapor Pressure Measurements

Daxue Huaxue ◽  
2021 ◽  
Vol 0 (0) ◽  
pp. 2107062-0
Author(s):  
Shuai Zhang ◽  
Jian Zhang ◽  
Shaowei Bian ◽  
Yaping Zhao ◽  
Li Shen ◽  
...  
Keyword(s):  
Vapor Pressure ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Pressure Measurements ◽  
Micro Flow ◽  
Vapor Pressure Measurements
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