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建立模拟真空管太阳热水器内流动与换热的数值模型来研究气候参数和技术参数对真空管型太阳热水器性能的影响,数值模型与实验结果吻合较好.研究结果表明,集热管越长,水箱内平均水温越高,但同时从集热管损失的热量越多,这反而会导致热水器效率下降.在该文的研究范围内,当管长由1.5 m增至2.1m时,水箱内平均水温升高10.5％～31.9％,同时效率降低了3.1％～11.0％.此外研究结果还表明,从集热管散失的热量占真空管型热水器总热损的80％.“,”A numerical model of the heat transfer and fluid flow in the evacuated tube solar water heater had been developed to investigate the effects of climatic conditions and technical parameters on the performance of all-glass evacuated tube solar water heater.The numerical results agreed well with the experimental data.The obtained results indicate that the average water temperature in the storage tank increases as the tube length increases.However,at the same time,the heat loss from the collector tube also increases,which makes the efficiency of evacuated tube solar water heater lower.In the research scope of this study,when the tube length increases from 1.5 to 2.1 m,the average water temperature in the storage tank increases by 10.5％-31.9％,meanwhile,the efficiency decreases by 3.1％-11.0％.Moreover,the results also showed that the heat loss from the collector tube takes account about 80％ the proportion of the total heat loss of the evacuated tube solar water heater.