Nanoparticles Thermodynamic Properties Of Nanofluids On Heat Transfer Enhancement

With the progress of thermodynamics and thermal engineering, many efforts have been devoted to the heat transfer enhancement. Although a variety of techniques are available to enhance heat transfer, major improvements in heat transfer capabilities have been held back because of the low thermal conductivity of conventional heat transfer fluids. Improvement of the thermal properties of energy transmission fluids is becoming a promising method of heat transfer enhancement.Modern nanotechnology provides new challenges and opportunities for thermodynamics. Some scholars put forward the brand-new conception of nanofluids which is a kind of heat transport carriers by appending nanoscaled metallic or nanometallic particles in basic fluids. Nanofluids are expected to exhibit heat transfer properties because nanofluids is superior to those of conventional heat transfer fluids.The nanotechnology and the heat transfer theory are applied in this dissertation. In the interest of investigating how the accession of nanoparticles changes the thermodynamics parameter, different nanoparticles have been mensurated. The token and heat capability of nanoparticles were provided, heat capability of nanoparticles are mensurated and the equation of heat capability and temperature quotiety is gained by lease quadric multiply method.The heat capability of nanoparticles mensurated is compare with that of corresponding coarse crystal and others in this dissertation and draw a conclusion.during the temperature section of 110K-390K, the heat capability of nanoparticles is increase by degrees along with the devrease of nanoparticles' size.By using both of the crystal lattice vibrant theory and lattice kinetic theory, the heat capability of nanoparticles is researched in this dissertation. The theoretical model of the nanoparticles is founded, and the relevant formulas are listed, then the heat capacity of nanoparticles is calculated out, and by comparing with the experimental heat capacity the result is drawed: the crystal lattice vibrant theory is accurater than lattice kinetic theory.In the interest of developing new type and effective heat transfer nanofluids and investigating mechanism and performance of heat transfer enhancement, nanofluids of different kinds and different particle sizes have been investigate throught experiment.Tests of heat weightlost and quantity of heat are done on nanofluids which collocated by different kinds and different particle sizes with different quality chroma and compare the experiment result, then find infection rule of nanoparticles property , quality chroma ,size,and suspend stability on nanofluids.Through the theoretic analysis and the experiment, this dissertation provide effective experiment method and credible experiment date for developing new high effect heat transfer intermedium of nanofluids and research of the mechanism and performance of nanofluids heat transfer enhancement.