机械5

本文设计120kw的冷水机组。 冷水机组包括四个主要组成部分：压缩机，蒸发器，冷凝器，膨胀阀，从而实现了机组制冷制热效果。冷水机一般使用在空调机组和工业冷却。冷水机的性能形式，大致可分为二种:风冷式冷水机和水冷式冷水机。 本次设计首先进行了对系统的热力计算，通过压焓图和热力性质表确定了各参数。其次通过理论功率和实际输气量进行了压缩机的选型。然后较为详细的进行了蒸发器的计算，主要包含了换热系数，热流密度和传热面积的计算。接着进行了冷凝器的设计与计算，通过估算传热管总长来确定最终的换热面积。最后是对节流阀的选型，通过计算压力差来确定节流阀的形式和型号。 通过这次设计，我们可以较为详细的了解冷水机组，并对以后的学习起到较大的帮助。 关键词：蒸发冷凝传热热力性质 窗体顶端 Abstract I
n this paper,the desig
n of water chiller is 120kw. The chiller co
nsists of four mai
n parts: compressor, evaporator, co
nde
nser, expa
nsio
n valve, so as to realize the thermal effect of refrigeratio
n system of the chiller.Cold water machi
nes ge
nerally used i
n air-co
nditio
ni
ng u
nits a
nd i
ndustrial cooli
ng.The performa
nce of cold water machi
ne ca
n be divided i
nto two types: air-cooled chiller a
nd cold water chiller. This thesis co
nsists of 5 sectio
ns, the first sectio
n to calculate the thermody
namic system, through the pressure e
nthalpy diagram a
nd table to determi
ne the parameters of.The seco
nd sectio
n through the theory of power a
nd the actual amou
nt of gas carried out compressor selectio
n.The third sectio
n details of evaporator calculatio
n, i
ncludi
ng calculatio
n of heat tra
nsfer coefficie
nt, heat flux a
nd heat tra
nsfer area.The fourth sectio
n is the desig
n a
nd calculatio
n of co
nde
nser heat tra
nsfer area, to determi
ne the fi
nal heat tra
nsfer by estimati
ng the total le
ngth of the tube.The last sectio
n is the selectio
n of the valve, by calculati
ng the pressure differe
nce to determi
ne the form a
nd type of throttle valve. determi
ne the form a
nd type of throttle . Through this desig
n, we ca
n have a more detailed u
ndersta
ndi
ng of the chiller, a
nd the future of lear
ni
ng to play a greater help. Keywords: evaporatio
n co
nde
nsatio
n heat tra
nsfer thermody
namic properties 目录 摘要 Abstract 前言··························································································································（1） 系统热力计算·························································································（4） 1.1给定条件··········································································································（4） 1.2热力计算所对应的压焓图以及参数列表······················································（4） 1.3热力计算过程·································································································（5） 1.4压缩机选型·····································································································（6） 蒸发器的设计与计算·············································································（7） 2.1蒸发器概述·····································································································（7） 2.2设计方案和条件的确定·················································································（8） 2.3流量的计算与结构的初步规划·····································································（8） 2.4计算传热面积································································································（11） 冷凝器的设计与计算···········································································（16） 3.1冷凝器概述····································································································（16） 3.2传热管的布置及主体结构············································································（17） 3.3计算传热面积································································································（19） 3.4连接管管径计算···························································································（22） 节流阀的选择······················································································（23） 4.1节流阀概述···································································································（23） 4.2选择膨胀阀形式、型号及冷量规格·····························································（24） 总结·························································································································（25） 附表及附图············································································································（26） 附录图1 R22饱和液体的热物理性质······························································（27） 附录图2饱和水和饱和水蒸汽的热力性质······················································（28） 附录图3 R22的压-焓图·····················································································（32） 附录图4水的物性参数表··················································································（33） 前言 冷水机组的工作原理 冷水机组包括四个主要组成部分：压缩机，蒸发器，冷凝器，膨胀阀，从而实现了机组制冷制热效果。 冷水机俗称冷冻机、制冷机、冰水机、冻水机、冷却机等，因各行各业的使用比较广泛，所以名字也就多得不计其数。随着冷水机组行业的不断发展越来越多的人类开始关注冷水机组行业任何选择对人类来说越来越重要，在产品结构上“高能效比水冷螺杆机组”、“水源热泵机组”、“螺杆式热回收机组”、“高效热泵机组”、“螺杆式低温冷冻机组”等为主的极具竞争力的产品结构其性质原理是一个多功能的机器，除去了液体蒸气通过压缩或热吸收式制冷循环。蒸汽压缩冷水机组包括四个主要组成部分的蒸汽压缩式制冷循环压缩机，蒸发器，冷凝器，部分计量装置的形式从而实现了不同的制冷剂。吸收式冷水机利用水作为制冷剂，并依靠之间的水和溴化锂溶液，以达到制冷效果很强的亲和力。冷水机一般使用在空调机组和工业冷却。在空调系统，冷冻水通常是分配给换热器或线圈在空气处理机组或其他类型的终端设备的冷却在其各自的空间，然后冷却水重新分发回冷凝器被冷却了。在工业应用，冷冻水或其它液体的冷却泵是通过流程或实验室设备。工业冷水机是用于控制产品，机制和工厂机械冷却的各行各业。冷水机按制冷形式一般可分为水冷式和风冷式，在技术上，水冷比风冷能效比要高出300到500的kcal/h；在安装上，水冷需纳入冷却塔方可使用，风冷则是可移动，无需其他辅助。 制冷形式 冷水机的性能形式，大致可分为二种 风冷式冷水机-特点 （1）免装冷却塔，安装容易，移动方便，适合于水源缺乏免装水塔场合 （2）低噪音风机马达，绝佳的冷却冷凝效果，稳定节流机构 （3）采用欧美进口高性能压缩机，高EER值，噪音低，运行稳 2.水冷式冷水机-特点 （1）人体工学面板，全自动化控制，配备精密电温控制器