【作者】 郭俊杰；

【导师】 蔡振雄； 陈武；

【作者基本信息】 集美大学 ， 轮机工程， 2010， 硕士

【摘要】 变风量空调系统具有显著的节能性,在陆用建筑上已应用多年,技术也日趋完善,但是在船舶上的应用却处在初始阶段。为此本文以船用变风量空调系统为研究对象,对该类空调系统的特点进行分析,在此基础上搭建船用变风量空调系统实验平台,并着重对船用变风量空调系统的运行特性和送风控制进行较为深入的理论分析和实验研究。船用变风量空调系统采用直接膨胀式蒸发器作为冷却盘管,送风系统与制冷机组直接配合使用,不存在中间冷冻水系统;船用变风量空调系统容量相对较小,变风量末端数目少,各末端风阀的调节变化较为频繁,系统负荷及总送风量的变动幅度大;系统风侧的调节控制与制冷机组侧的调节控制直接相互影响、相互干扰。船用变风量空调系统实验平台由变风量空调系统和测试采集系统构成。变风量空调系统由配备变风量末端的空气处理系统与用于对空气进行冷却除湿处理的直接膨胀式(DX)制冷机组构成;测试采集系统则由数据采集仪、传感器和计算机等构成。利用搭建的实验平台,对提出的船用直接膨胀式变风量空调系统的运行特性进行实验研究。考察在降温工况、在空调舱室设定温度以及空调舱室负荷发生阶跃变化的情况下各空调舱室的温度、变风量末端阀门开度、送风温度、送风机运行频率,蒸发温度、冷凝温度、压缩机运行频率等参数的变化情况,分析各参数变化的原因,研究VAV末端,变频风机,变频压缩机等运行性能。实验结果表明,该类船用变风量空调系统实现了对舱室温度的良好控制,各个空调舱室可以独立控制。对利用静压控制单元控制送风静压和利用变频风机控制送风静压两种不同的送风控制方式进行比较研究。考察在降温工况和在不同的舱室设定温度以及舱室负荷发生阶跃变化的情况下,舱室温度,系统风侧和制冷机组侧各参数变化的异同;考察相同工况条件下,系统运行的功耗情况。研究发现两种控制方法都满足对空调舱室温度的良好控制和各空调舱室的独立控制;采用变频风机控制送风静压的船用变风量空调系统比采用静压控制单元控制送风静压的船用变风量空调系统节能。更多还原

【Abstract】 The variable-air-volume air-conditioning(VAV A/C)system is believed to be significantly energy-saving and find more and more application in buildings. However the application of such A/C systems on ships is still at the initial stage. In this thesis the research about marine VAV A/C systems was carried out, The features of marine VAV A/C systems were analyzed firstly. On this basis, an experimental rig was built. The in-depth theoretical analysis and experimental study on the operating characteristics and supply air control of a marine VAV A/C system were then conducted.In the marine VAV A/C system, a direct expansion (DX) evaporator is used as cooling coil. The VAV air-distribution system is directly connected with the refrigerating unit, without intermediate chilled water system. System capacity is relatively small and the number of VAV terminals in the system is few. Hence the regulation and variation of damper opening in terminals are comparatively frequent, and the system load and total supply air flow rate have a large varying range. The controls of system’s air-side and refrigerating-unit side directly interfere with each other. In this system a tube-in-tube type condenser with sea water cooling is adopted.The marine VAV A/C experimental rig is made up of a VAV air-conditioning system, and a measuring and acquisition system. The VAV air-conditioning system consists of a VAV air handling system equipped with VAV terminals and a direct expansion refrigerating unit which evaporator is directly used for air cooling and dehumidifying. The measuring and acquisition system is composed of data acquisition instrument, various sensors and a central data-processing computer, etc.Using this experimental rig, an experimental study was carried out to firstly investigate the operating characteristics for the marine direct expansion VAV A/C system. The system’s cooling-down performance and its responses to step-changes of the cabin setting air temperatures and inner cooling load were examined. The changes of such parameters as cabin temperature, VAV terminals’opening, supply air temperature, fan operating frequency, evaporating temperature, condensing temperature, compressor operating frequency were analyzed. The performance of VAV terminals, variable-frequency fan and compressor was studied. The experiment results showed that the marine VAV A/C system could achieve good and independent control for air temperatures of air-conditioning cabins. A comparative study for the marine VAV A/C system working with two different supply air pressure/flow rate control methods was made. One method was that the supply air static pressure/ flow rate in the system was regulated by a variable-frequency fan, the other by a static pressure control unit. The cabin temperatures, other various parameters respectively for air handling side and refrigeration side, especially the system’s power consumption were compared in detail. It can be concluded from the comparative study that both methods of supply air static pressure control could achieve desirable control results. The marine VAV A/C systems equipped with a variable-frequency fan to control supply air static pressure is more energy-saving than that with a static pressure control unit.更多还原