Impaction Of Nano-refrigeration-oil On The Saturated Vapor Pressure Of Refrigerant HFC134a

Application of nano-powder materials in refrigeration system, by way of replacing refrigeration oil with nano refrigeration oil, is an important means to improve the energy efficiency of a refrigerator as well as to extend the equipment life.In this paper, dispersion stability of nano-particles in nano refrigeration oil was studied by experiments. The saturated vapor pressure of refrigerant that mixed with mineral nano refrigeration oil was measured. The purpose of this paper is to provide base data for application of nano-particles in the refrigerant that mixed with mineral oil, and to analyze the mechanism of nano-particles in the refrigerant that mixed with mineral oil as well as to explore the rule that impaction of nano refrigeration oil on the saturated vapor pressure of refrigerant.The main works included:1. Preparation of nano refrigeration oil and its stability.Nano-CuO refrigeration oil and nano-NiFe2O4 refrigeration oil ware prepared by means of ultrasonic concussion and adding appropriate dispersant. By way of observation of settlement and UV-visible absorption spectroscopy, the dispersion stability of nano refrigeration oil was estimated.The results show that:(1) Adding appropriate dispersant could significantly improve the dispersion stability of nano-particles in mineral oil, and corresponds to a certain content of nano-particles, the amount of dispersant had an optimal value, not the more the better.(2) In order to achieve good dispersion stabilizing effect, that concussion heating should choose the low-frequency ultrasound and suitable low temperature, however when using the heating tank, high temperature is better.2. Impaction of nano-refrigeration oil on the saturated vapor pressure of refrigerant.By way of the steady-state method, the saturated vapor pressure of pure refrigerant R134a and R22 were measured at the range of 263k~323k. The test data were compared with the standard data provided by NIST to verify the reliability of test system and the accuracy of the test data. The maximum deviation were -0.191 and -0.183 respectively, standard deviation were 0.095 and 0.103 respectively.At the range of 263k~323k, the saturated vapor pressure of pure refrigerant and that of the mixtures of the refrigerant respectively mixed with mineral refrigeration oil, dispersion oil sol, and mineral nano refrigeration oil were measured.The results as fellows:(1) The saturated vapor pressure of refrigerant mixed with mineral refrigeration oil is lower than that of the pure refrigerant, and the difference between them is higher as the mass fraction of refrigeration oil increased;(2) Under the condition of the same mass fraction of refrigeration oil, impaction of mineral oil on the saturated vapor pressure of R22 is greater than that of POE oil on the saturated vapor pressure of R134a.(3) When there is no nano-particles, impaction of mineral oil on the saturated vapor pressure of R134a is less than that of POE on the saturated vapor pressure of R134a. Where, when the mass fraction is 5%, Mineral oil: maximum deviation is -0.627, standard deviation is 0.376; POE oil: maximum deviation is -2.514, standard deviation is 0.839;(4) When with the same mass fraction of refrigeration oil in the refrigerant, impaction of dispersion mineral oil sol on the saturated vapor pressure of R134a is equivalent that of the pure mineral refrigeration oil on the saturated vapor pressure of R134a. Where, when the mass fraction is 5%, Mineral oil: maximum deviation is -0.627, standard deviation is 0.376; SDBS oil sol: maximum deviation is -0.365, standard deviation is 0.216; Span80 oil sol: maximum deviation is -0.827, standard deviation is 0.530;(5) The saturated vapor pressure of refrigerant mixed with nano refrigeration oil is lower than that of refrigerant mixed with pure mineral oil or that of pure refrigerant, and the difference falls as the mass fraction of nano refrigeration oil drops;(6) Impaction of mineral nano refrigeration oil on the saturated vapor pressure of R134a is equivalent that of pure POE on the saturated vapor pressure of R134a. Where, when the mass fraction is 5%, Pure POE oil: maximum deviation is -2.514, standard deviation is 0.839; Nano-CuO refrigeration oil: maximum deviation is -2.128, standard deviation is 0.745; Nano-NiFe2O4 refrigeration oil: maximum deviation is -2.658, standard deviation is 0.828;...