Mechanisms And Experimental Correlation Of The Saturated Vapor Pressure Of Refrigerant Containing Nano-refrigeration-oil

The function of refrigeration oil in vapor compression refrigeration system is to lubricate and pressurize the compressor. When the system runs, refrigeration oil will circulate in the system with refrigerant. It is helpful to improve the lubricating ability of friction surface in compressor and heat transfer performance of refrigerant-oil mixture by adopting appropriate nano-refrigeration-oil. As a result, energy effciency and reliability of the refrigeration system will be improved. When the refrigerant containing nano- refrigeration-oil, its thermo physics properties, such as saturated vapor pressure, will be changed. Then, the performance of refrigeration system wil be influnced. The fundamental purpose of this thesis is to analyse the variation of refrigerant after containing nano-refrigeration-oil by measuring its saturated vapor pressure; discuss the mechanism of nano-refrigeration-oil's action on the saturated vapor pressure of refrigerant; incidence the outcome of experiment. The primary task and conclusion of this thesis list as follow:1. Conducted an investigation in preparing and properties of the nano-refrigeration-oil. After preparing nano-refrigeration-oil added with nano-NiFe₂O₄, C60 and mixed nanoparticles, we investigated their properties by means of Fourier transform infrared spectrometry method. The results were as follows:1) The compositional formulation of Tween and Span was adopted to prepare naphthenic base nano-refrigeration-oil containing nano-NiFe₂O₄, C60 or mixed nanoparticles with superior stability.2) Nanoparticle and dispersant may change some of absorption characteristic peaks of refrigeration oil. For instance, the infrared spectrum of mineral refrigeration oil 3GS would generate similar infrared characteristic peaks as 160SZ, such as aliphatic acetate esters, aliphatic ethers and primary aliphatic alcohols. These characteristic peaks'corresponding functional groups were the main factors that improve the dissolving ability between 3GS and R134a.2. Experimental study on the saturated vapor pressure of refrigerant after containing nano-refrigeration-oil. The saturated vapor pressure of refrigerant mixed with refrigeration oil and nano-refrigeration-oil were measured with different mass fractions from 1 to 9wt%, at the temperature range from 263 to 333K. The results were as follows:1) The pressure deviation of the refrigerant-oil mixture were increased as the temperature rised at the same mass fraction of refrigeration oil.2) Impaction of refrigeration oil KT56 on the saturated vapor pressure of R22 was greater than 3GS obviously at the same mass fraction of refrigeration oil. It showed that the dissolving ability of KT56 and R22 was better than 3GS and R22.3) Impaction of KT56 based nano-refrigeration-oil on the saturated vapor pressure of R22 was greater than pure KT56 obviously at the same mass fraction of refrigeration oil. It showed that the dissolving ability of KT56 based nano-refrigeration-oil and R22 was better than pure KT56 and R22.3. The experimental data of refrigerant oil mixture on saturated vapor pressure were correlated. The working achievements were as follows:1) A saturated vapor pressure equation of refrigerant-oil mixture was developed in this thesis, combining with Cavestri equation and Xiang equation. A nonlinear least square method was employed to fit parameters of the equation. The saturated vapor pressure experimental data of refrigerant oil mixture were compared with the calculated value of the new equation at different mass fractions from 1 to 5wt%. The result showed that: The maximum and mean deviation of R22-KT56 mixture is 0.42% and 0.133%, respectively; The maximum and mean deviation of R22-3GS mixture is 0.41% and 0.193% , respectively.2) A saturated vapor pressure equation of refrigerant containing nano-refrigeration -oil by means of coupling the mass fractions of nano-refrigeration-oil. The saturated vapor pressure experimental data of refrigerant and nano-oil mixture were compared with the calculated value of the new equation at different mass fractions from 1 to 5wt%. The result showed that the calculated value of the equation match all of the experimental data within the deviation of±0.23%.