15kgh柜式除湿机设计.docx

1、摘要空气的湿度影响着人们的生活和工作，除湿系统在国民经济中发挥着极其重要的作用，被广泛地应用于机械制造、光学仪器、电子、食品、化学、医药及近几年发展起来的设施农业等生产领域。调温除湿机因其体积小、除湿效率高、运行方便等特点被广泛运用于各种需要除湿的场合。本课题研究的是柜式除湿机的设计。所设计的除湿机属于调温除湿机，其除湿的方法是将湿空气冷却到露点温度以下，除去产生的冷凝水，从而使空气干燥。调温除湿机主要包括空气循环部分、制冷循环部分和电器控制部分。空气循环部分是由进风口、出风口、风道、离心式风机组成。制冷循环部分主要由蒸发器、冷凝器、压缩机、节流机构组成。从压缩机出来的高温高压的制冷剂蒸气在冷

2、凝器中冷凝，放出热量变成高压液体。高压液体经过节流后进入蒸发器，吸收热量变成低温低压的蒸气。制冷剂蒸气又进入压缩机，如此循环，与空气交换热量。调温除湿机有两个冷凝器，分别是风冷冷凝器和水冷冷凝器。空气在风机的驱动下分别经过蒸发器和风冷冷凝器，制冷剂在蒸发器中的蒸发吸热冷却空气，产生除湿效果，在风冷冷凝器中冷凝放热加热空气。而通过改变水冷冷凝器中制冷剂的冷凝放热量，调节离开风冷冷凝器的空气温度，从而达到调温的目的。电气控制部分控制着电源的开关、风机和压缩机的启闭以及压差保护器等装置。本论文描述的是15kg/h柜式除湿机的设计，设计内容包括：环境工况及需求分析、制冷循环热力计算、蒸发器和风冷冷凝器

3、设计计算。课题的研究需要运用工程热力学、传热学、流体力学、制冷原理及相关技术专业课程的知识。根据除湿量、风量、进口空气状态确定制冷量，进而选择压缩机，进行制冷循环的热力计算。根据空气和制冷剂的进出口状态参数、换热量，对蒸发器和冷凝器进行结构设计、热量计算、校核计算，最终确定其结构与尺寸，并进行阻力计算。设计时重点考虑了蒸发器和冷凝器强化传热的问题，通过换热管的叉排布置、安装翅片等方法增加空气侧传热系数，进而减少换热面积，降低制造成本。考虑到蒸发器翅片上会有大量水蒸气凝结，蒸发器翅片采用清水膜处理，便于凝结水的流出。但是调温除湿机易出现的结霜现象在本研究中并未进一步展开。通过本课题的研究，可以看

4、出调温除湿机具有较高的除湿效率，体积小，运行方便等特点，同时还能够调节室内空气温度，改善空气质量，避免空气湿度太大引起霉菌，影响身体健康。所以调温除湿机在库房、办公室、医疗、图书馆等多种场合使用，具有广泛地应用前景。关键词：除湿机 蒸发器 冷凝器 压缩机AbstractThe air humidity has a significant effect on peoples life and work. Dehumidification system plays a major role in the national economy which is widely used in many a

5、reas such as machinery manufacturing, optical instruments, electronics, food, chemistry, medicine and agriculture developed in recent years. Thermostat dehumidifier has been widely used in various areas requiring dehumidification because of its small size, high dehumidifying efficiency and convenien

6、t operation.This research is about the design of cabinet dehumidifier which belongs to thermostat dehumidifier. Dehumidification method is to cool wet air to dew point temperature, remove condensed water and dry air. Air dehumidification machine comprises air circulation part, refrigeration cycle an

7、d electrical control part according to the structure and function. Air circulation part is composed of air inlet, outlet, duct and centrifugal fan. Refrigeration cycle part mainly consists of evaporator,condenser,compressor and throttlemechanism. High-temperature and high-pressure refrigerant gas fr

8、om the compressor is condensed in the condenser and changed into high-pressure liquid owing to emitting heat. High-pressure liquid flows into the evaporator after throttling and becomes low-temperature and low-pressure gas because of absorption of heat. The refrigerant gas is sucked into the compres

9、sor for compression, and so forth cycle, to exchange heat with air. Temperature-regulated dehumidifier has two condensers including a water-cooled condenser and an air-cooled condenser. Under the drive of a fan, air flows through the evaporator and air-cooled condenser. Air is cooled and dehumidifie

10、d due to heat absorbed from refrigerantevaporation, which is heated by condensation heat transfer in air-cooled condenser. At the same time, temperature of air leaving air-cooled condenser is regulated through changing heat transfer in a water-cooled condenser. Electrical control part controls the p

11、ower switch and operation of centrifugal fan, compressor andpressure differentialprotection devices.This paper describesthedesign of 15kg/h cabinet dehumidifier including analysis of environmental conditions and requirements, thermodynamic calculation of refrigeration cycle and design calculations o

12、f evaporator and air-cooled condenser. This design involves the professional courses of engineering thermodynamics, heat transfer, fluid mechanics, refrigeration principle and related technical knowledge. In line with dehumidification capacity,air flow rate and inletparameters, the compressor is sel

13、ected and thermodynamic calculation of refrigeration cycle is finished. Then according to inlet and outlet parameters of air and refrigerant as well as heat transfer, structure design, heat calculation and verifying calculation of evaporator and air-cooled condenser are completed in order to determi

14、ne their appearance structure and resistance pressure drop. In this design, the problem of enhancing heat transfer of the evaporator and condenser is considered. With staggeredarrangement of heat transfer tubes and installation of a fin, the air-side heat transfer coefficient is increased aiming to

15、decrease heat transfer area and manufacturing cost. Considering that there will be a large number of water vapor condensation on the evaporator fin, the membrane treatment is carried on to facilitate the condensate flow out. However, thermostat dehumidifier is prone to frost phenomenon, which is not

16、 researched further.Through the research of this topic, we can find that thermostat dehumidifier has higher dehumidification efficiency, small size, convenient operation, etc. At the same time, the dehumidifier also can regulate indoor air temperature, improve air quality and avoid mold which is caused by high humidity. So temperature-regulated dehumidifier is used in a variety of circumstances, such as warehouses, offices, libraries and so on, and