| Since energy crisis occurred in 1970's, latent heat thermal energystorage(LHTES) has gained more attention than before due to its being the keyelement to accomplish energy recovery and utilization of solar energy, industrialwaste heat and off peak electricity. Compared with developed countries, in this area, China still has a long way togo. In order to shift the peak heating and cooling loads to off-peak hours, Chinesegovernment has carried out the "peak and off-peak price" policy and research aboutLHTES is gradually becoming a new focus again. Based on the existing theoreticaland experimental study, the following aspects are investigated in this thesis. The emphases in this paper are the measurement and analysis of thermalcharacteristics of stearic acid as phase change material and the design and simulationof the Latent Heat Thermal Storage Radiator. At first the background andsignificance of the work are mainly introduced, as well as the concept and type ofthermal storage. Then the thermal performance of the unit is measured and heattransfer characteristics of melting process of stearic acid is studied under differentheat flux conditions to determine the influence of heat flux on the melting process. Anew fin is designed and fixed to the electrical rod to enhance the thermal response ofstearic acid and the influences of the fin size and pitch on the enhancement arestudied and analyzed. The following is the experimental investigations onsolidification process of stearic acid. The influences which the inlet temperature andReynolds number of the cooling water have on the solidification process arepresented. Figures that display how heat flux change versus time has been drawn andanalyzed. In the end, choosing PCM, design calculation and assembly of the radiatorare described in details. Mathematical model on heat transfer of the LHTES radiatoris attempted to establish. It also explains the result of the comparison between curveacquired by experimental data and the one from model.
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