在太阳能热发电系统的实际应用中,相变蓄热技术可以克服太阳能受环境因素影响的缺点和提高系统的可靠性和容量.建立了单级高温壳管式相变蓄热器的二维物理和数学模型.基于焓法模型采用有限容积法数值模拟相变蓄热材料的固-液界面位置和温度随时间变化情况,分析了空气入口温度对熔化时间的影响.拟合出熔化时间与入口温度的函数关系式.讨论了空气出口温度的变化规律.研究结果表明:空气的最佳入口温度和流速分别为1025K、2.04 m/s,对应的熔化时间为6887 s.研究结论对高温壳管式相变蓄热器的优化设计和节能运行具有重要的理论指导价值.%In the practical application of the solar thermal electricity generating systems, the latent thermal energy storage can not only overcome the disadvantage of the influence of environment to solar energy , but also improve the reliability and capacity of the system. A shell-tube thermal energy storage structure with two-dimensional physical and mathematical model is adoptal, using finite volume method and enthalpy method model to simulate the solid/liquid interface positions and temperature as the time change, and analyse the impact of inlet-temperature to the melting time, fitting the function between melting time and inlet temperature , discuss the law of air outlet temperature. The conclusion shows that the best inlet-temperature is 1 025 K, the velocity is 2. 04 m/s and the melting time is 6 887 s. The conclusion from the simulation has vast theory value to the design and energy saving of shell-tube latent heat thermal energy storage.
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