毕设论文循环冷却系统的优化设计.doc

循环冷却系统实验装置的优化设计【摘要】冷却塔是一种重要工业循环用水装置,它利用不同温度的空气和水两种介质通过直接接触和间接接触方式来降低水温以达到循环用水的目的。在大型中央空调系统中,由冷却塔和冷水机组组成的空调水系统的能耗约占整个空调系统能耗的 55% 左右,其中冷却塔子系统的耗电量占整个系统耗电里的 15% 左右,而目前的空调冷却塔系统的设计是按全年最不利工况进行设计的,如何改善其工作状况,实现节能的目的,具有重要意义。由于整个暖通空调系统是按最大负荷设计,而空调系统大多数时间内处于部分负荷状况下运行,如果能根据负荷在线找出空调系统的最佳工作点,并通过控制系统实现能量最佳匹配,将大幅度地降低空调系统能耗。本文通过分析冷却塔系统中各个主要设备的能耗特点,提出了对冷却塔系统节能的优化方案,使得冷却塔组在任何工况下运行都能保持最佳的运行状态,从而起到节能的效果。本文中通过控制风机台数并配以风阀启闭及变流量下全塔组配水为关键的节能技术,辅以塔体优化、设计及检测等方面的科技进步,以此将成本降到最低并且充分发挥冷却水的冷却潜力提高循环使用率从而使节能效益最大化,达到节能减排的目的。研究出一种控制简单、能耗小、散热面积利用充分的冷却控制方法,通过搭建模型,模拟一台冷却塔组来实现上述控制方法。本实验台加入了 PL C 装置,对当下冷却塔组进行仿真控制,配合目前流行的自动化设备,通过传感器的数据采集等,对冷却塔组的整体结构、换热面积、循环水流速等相关因素进行设计和改善,真正实现了自动控制。同时进行冷却塔组实验平台的模型搭建、选型,通过更多的实验数据来增强节能冷却塔组的说服力。关键词: 冷却塔;节能; PLC ;自动控制系统循环冷却系统实验装置的优化设计【 Abstract 】 Cooling tower is an important industrial water recycling device, two media using different temperatures of air and water through direct contact and indirect contact method to lower the water temperature to achieve the purpose of circulating water. Air- conditioning water system by the cooling tower and chiller energy consumption accounts for about 55% of the energy consumption of the entire air conditioning system, and cooling tower subsystem power consumption accounted for about 15% of the overall system power consumption ina large central air conditioning system while the design of air-conditioning cooling tower system is designed according to theannual most unfavorable conditions, The significance ofhow to improve their working conditions and to achieve the purpose of energy saving as great philosophically asit is scientifically. Best match of the entire HVAC system is designed according to the maximum load, while the air-conditioning system is running under partial load conditions most of the time. According to the load-line to find out the optimum operating point of the air-conditioning systems, and air conditioning energy consumption will be reduced by adjust the system to achieve energywill significantly. Based on the analysis of