Experiment And Model For The Thermal Conductivity And Specific Heat Capacity Of Lithium Bromide Solution At High-temperature

Energy is one of the most fundamental factors of human beings, the energy consumption is growing fast along with economic development, as well as the whole community. On the other hand, a lot of environmental problems arising from the use of fossil fuels increasingly prominent. The second absorption heat pump using low-grade waste heat will increase to a higher grade, plays an important role in the industrial waste heat recovery and improve energy efficiency, got a wide concern by scholars.At present, LiBr-H2O is the major industrialized working fluid for heat pump, but there is just a few study on the basic thermal properties,such as thermal conductivity and specific heat capacity of LiBr solution at high temperature, which impact the theoretical research and application of high temperature heat pump. So the research on thermal properties of LiBr solution at high temperature have important academic significance and practical value.The transient hot-wire technique has become the leading method for the measurement of the thermal conductivity of liquids. The use of this method for electrically conducting liquids, however, has revealed several limitations. To solve this, we use a quartz glass capillary filled with mercury as a hotline to measure the thermal conductivity of lithium bromide solution at high-temperature. The thermal conductivity of aqueous solutions of lithium bromide ranging in composition from 45 to 65wt% and in temperature from 150 to 250℃ at 2MPa pressure were measured, the maximum deviation of the experimental results and the literature is 2.97%.Based on adiabatic method for specific heat capacity measurement. New adiabatic calorimetry were developed to measure the specific heat capacity of LiBr solution. The maximum deviation is 2.72%.The thermal conductivity and specific heat capacity of the lithium bromide solutions was correlated with temperature in K and composition X in wt%. The correlation was able to fit the data with an average absolute deviation of 0.6% and a maximum deviation of 1.6%.According to the electrolyte solution theory, establish a model for thermal conductivity and specific heat capacity of lithium bromide solution, and the results agree well with experimental data with a maximum deviation of 1.11% and 4.93%.