Study On The Thermal-physics Property And Stability Of LiBr Aqueous Solution Added Nano-particles And Relevant Dispersants Working At High Temperature

As energy crisis intensifies and energy demand grows, energy saving has been the themeof the modern society. Lithium bromide(LiBr) absorption chiller is such a refrigerating unitthat its heat resource are usually waste heat and recovered energy, so the LiBr absorptionchiller has huge energy saving potentiality. However, the traditional absorption chiller hasseveral disadvantages, such as huge volume, poor heat transfer performance and low workefficiency, so its energy saving effect isn’t satisfactory.Heat and mass transfer properties of working medium for a LiBr aqueous solutionabsorption chiller and its generating temperature are the key factors of its performance.Adding nano-particles to LiBr aqueous solution can enhance its heat and mass transferproperties, reduce its generating temperature and further improve its energy efficiency. Inorder to make the nano-particles uniformly and stably distributed in lithium bromide aqueoussolution, considering the high working temperature and the special ‘sintering phenomenon’ ofwater-based nano-fluid, it is needed to choose the kind of dispersants which is hightemperature resistant. This paper aimed to search for new types of heat transfer medium ofLiBr aqueous solution absorption chiller and some kinds of heat resisting dispersant, and theauthor also studied the influence of nano-particles and dispersants on the properties of theLiBr aqueous solution. Firstly, the author analyzed the current researching characteristics ofnano-fluids and LiBr aqueous solution added nano-particles, then investigated nano-particles’influences on generating temperature and surface tension of LiBr aqueous solution, andfinally studied the stability of nano-fluids prepared in experiment. In addition, the author alsoexplored a new ‘wet chemical method’ to prepare nano-fluids. The experiment show thatnano-particles and dispersants can be helpful and useful to improve the heat transfercharacteristics of LiBr aqueous solution and the nano-fluids prepared with wet chemicalmethod would have better stability than that prepared with traditional’ two-step method’. Inshort, the investigation not only widen the application scope of LiBr absorption refrigeratingchiller but also lay a base for further researching the characteristics of nano-fluids.