【作者】 李新梅；

【导师】 黄护林；

【作者基本信息】 南京航空航天大学 ， 热能工程， 2009， 硕士

【摘要】 本文针对目前对太阳能吸收式制冷系统的开发研究和市场需求,设计了一台小型(5kW)的单效太阳能溴化锂吸收式制冷机,采用了传热传质分离形式的吸收器,并对机组的其他换热器也进行了优化设计。论文首先根据设计工况,做了整个系统的设计计算,设计了太阳能吸收式制冷系统的各个部件:发生器、汽液分离器、冷凝器、蒸发器、吸收器以及节流装置等,并绘制出了其设计图纸。编制了5kW制冷量的单效溴化锂吸收式制冷机组的设计计算程序,对发生温度、吸收温度、冷凝温度、蒸发温度及外界条件(冷冻水出口温度、加热热源的温度、冷却水进口温度及各流量等)的变化对机组COP的影响进行了数值模拟分析,得出发生温度越高、冷凝温度越低、蒸发温度越高,机组的性能系数就越高。机组制冷量在一定范围内随热水流量、冷却水流量的增加而增加,冷冻水流量变化对机组制冷量没有太大的影响。其次,建立了吸收器的计算模型,对吸收器内溶液喷淋后的微粒分布状态做了模拟分析,从而找出最佳的喷淋孔径和溶液喷淋量。最后对制冷机组进行了实验测试,主要研究了机组的加热热水、冷却水、冷冻水的温度及制冷剂的蒸发温度、冷凝温度和发生器、吸收器溶液温度随时间的变化关系,从而得出机组制冷量和COP的变化状况。通过实验得到,热水温度在85-90℃之间时机组制冷量达到最高值,适用于太阳能热水型单效吸收式制冷机,但其COP值不高。更多还原

【Abstract】 Considering the research and market demand for solar energy absorption system, a small type single-effect solar energy lithium bromide absorption machine of 5kW refrigeration capacity is designed. The heat and mass transfer separated absorber is used, and the design of the others exchangers in the machine are optimized.According to the working conditions, the calculatation of whole system are completed, all components such as the generator, the vapor-liquid separator, the absorber, the evaporator, the condenser and the throttle are designed. The design blueprints are drawn. The calculation code of solar energy hot water type absorption refrigeration is developed, numerical simulation on cooling performance is carried out, the performance variations with the temperature of generation, absorption, condensation, evaporation and exterior conditions(such as the temperature and flux of chilled water, hot source and cooling water) by changing different working conditions are obtained. The calculated results show that with generation temperature increasing, condensation temperature decreasing, evaporation temperature increasing, COP increases. In a certain range, the refrigeration capacity increases with the increasing of hot water and cooled water fluxes, but the flux of chilled water almost has no any effect on the refrigeration. The calculation model of absorber is set and simulated the paiticles distributing after being jetted from the small hole. The diameter of the jetting hole and the best spraying solution quantity are optimized. At last, the experiment measurements are carried out and the interactions between time and the temperature of chilled water, hot source, cooling water, refrigeration medium and solution are obtained. The chiller has the maximum refrigeration when the hot water temperature is between 85 and 90℃, it is suitable with solar energy application, but its COP of the single-effect absorption refrigerator is low.更多还原