【作者】 何浩；

【导师】 施光林；

【作者基本信息】 上海交通大学 ， 机械电子工程， 2011， 硕士

【摘要】 制冷空调行业已经有了100多年的发展历史。压缩机、蒸发器、冷凝器和节流阀是四个基本部件。节流阀有了70多年的历史。从最初没有调节作用的固定节流口,到人工调节的手动膨胀阀,到后来自动调节的热力膨胀阀以及电子膨胀阀。迫于能源危机的压力,对节能要求的呼吁越来越高。电子膨胀阀由于具有调节范围宽,具有强大的过热度控制功能和智能化调节特性,反应速度快以及能实现良好的机电一体化等优点,备受人们青睐。本论文主要研究一种新原理和结构的电子膨胀阀。这种阀是靠PWM脉冲电压信号驱动的电磁膨胀阀。本论文提供了一种基于理论、经验计算与软件仿真结合,多仿真软件协同配合设计电磁膨胀阀的方法。其特点是可以快速、精确地设计满足用户要求的膨胀阀。具体内容有:1)应用理论计算与FLUENT仿真相配合的方法,进行了阀口结构和尺寸的设计,分析了阀口处压力及流场的分布情况,以实现阀的通径要求和流道优化;2)应用理论计算与ANSYS软件的电磁模块协同配合进行了电磁铁结构的设计以及尺寸的改进和优化;3)应用ANSYS仿真软件对阀的关键零部件(如较薄尺寸的阀口和聚四氟乙烯密封圈)进行了强度和变形的校核和分析,确保主要零件的强度和变形满足阀的性能要求;4)应用AMESim仿真软件进行了系统的动态仿真分析,分析了影响阀的动作响应的主要因素。根据以上思路,本论文设计了一个直动型小通径电磁膨胀阀和一个先导式大通径电磁膨胀阀,并申请了发明专利,并开发出直动型小通径电磁膨胀阀实验样机,以及为电磁铁线圈提供PWM信号驱动的24V直流控制器。本论文完成了直动型小通径电磁膨胀阀实验样机的开环流量,气密性和最大开阀压差等实验,并将该阀置于相应的制冷系统中开展了系统匹配实验,以及在不同占空比下系统性能的对比实验。通过该阀的性能试验以及制冷系统应用实验证明,该阀性能优良,能够满足制冷系统的要求,达到了设计的目的,证明了阀的优良性能,并且其控制器经过实际应用也达到了设计要求。更多还原

【Abstract】 Refrigeration and air-conditioning industry has more than 100 years of history. Compressor, evaporator, condenser and expansion valve are four basic components. Expansion valve has more that 70 years of history. It has mainly experienced there stages: the initial fixed orifice, the expansion valve adjusted by manual, the thermal expansion valve and the electronic expansion valve which can be regulated automatically. Forced by the pressure of the energy crisis, energy-saving has been emphasized. The electronic expansion valve has wide adjustment range and a strong and intelligent superheat control regulation characteristics. It also has very fast response characteristic and it has achieved good mechanical and electrical integration. So it has been widely used nowadays. This paper is to design a novel electromagnetic expansion valve, which is driven by PWM pulse.This article aims to provide a systematic method to design a novel electromagnetic expansion valve, which is based on the combination of theory, experience and the combined simulation with multiple simulation software. It can be used to design the expansion valve quickly and accurately to meet the requirements of the users. The contents include: 1)theoretical calculation and FLUENT simulation are carried out to design the structure and parameters of the valve port and to check the distribution of the pressure and the flow field to meet the requirements of the flow path and flow rate of the valve; 2)theoretical calculation and the ANSYS software are used to optimize the structure and size of the electromagnetic solenoid; 3)ANSYS simulation software is applied to check the stress and deformation of the key parts of the valve(such as the valve port and the seal and so on) to ensure that the strength and performance of these parts meet the design requirements; 4)AMESim simulation software is applied to simulate the dynamic characteristics of the valve,(including the movement of the spool and the flow rate of the valve) to find out main factors to influent the dynamic performance of the valve.Based on the above ideas, the paper has designed a direct action type valve used in smaller valve port and a pilot operated valve used in larger valve port and two patents has been applied. Due to time constraints, only the smaller valve has been produced. In order to test the valve, the PWM controller supplying 24V DC voltage has been designed and produced.In this thesis, Many experiments has been carried out for the valve: such as open-loop flow rate test, leaking test, the differential pressure when the valve cannot be opened. Some test has done to put the valve into the air-conditioning system to match the system. The system performance under different duty cycles has been analyzed. After these tests, all the design requirements of the valve have been met and the controller can meet the design requirement through practical application too.更多还原