CN1946318A - 使用微通道管路的抗污垢冷凝器 - Google Patents

使用微通道管路的抗污垢冷凝器 Download PDF

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CN1946318A
CN1946318A CNA200580012895XA CN200580012895A CN1946318A CN 1946318 A CN1946318 A CN 1946318A CN A200580012895X A CNA200580012895X A CN A200580012895XA CN 200580012895 A CN200580012895 A CN 200580012895A CN 1946318 A CN1946318 A CN 1946318A
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refrigerated merchandiser
fins
microchannel
inch
condenser coil
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CN1946318B (zh
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E·D·小达迪斯
R·H·L·蒋
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Carrier Global Corp
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Carrier Comercial Refrigeration Inc
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B39/00Evaporators; Condensers
    • F25B39/04Condensers
    • AHUMAN NECESSITIES
    • A47FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47FSPECIAL FURNITURE, FITTINGS, OR ACCESSORIES FOR SHOPS, STOREHOUSES, BARS, RESTAURANTS OR THE LIKE; PAYING COUNTERS
    • A47F3/00Show cases or show cabinets
    • A47F3/04Show cases or show cabinets air-conditioned, refrigerated
    • AHUMAN NECESSITIES
    • A47FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47FSPECIAL FURNITURE, FITTINGS, OR ACCESSORIES FOR SHOPS, STOREHOUSES, BARS, RESTAURANTS OR THE LIKE; PAYING COUNTERS
    • A47F3/00Show cases or show cabinets
    • A47F3/04Show cases or show cabinets air-conditioned, refrigerated
    • A47F3/0404Cases or cabinets of the closed type
    • A47F3/0408Cases or cabinets of the closed type with forced air circulation
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25DREFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D21/00Defrosting; Preventing frosting; Removing condensed or defrost water
    • F25D21/06Removing frost
    • F25D21/12Removing frost by hot-fluid circulating system separate from the refrigerant system
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28DHEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D1/00Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
    • F28D1/02Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
    • F28D1/04Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits
    • F28D1/053Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being straight
    • F28D1/0535Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being straight the conduits having a non-circular cross-section
    • F28D1/05366Assemblies of conduits connected to common headers, e.g. core type radiators
    • F28D1/05383Assemblies of conduits connected to common headers, e.g. core type radiators with multiple rows of conduits or with multi-channel conduits
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00Tubular elements; Assemblies of tubular elements
    • F28F1/10Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
    • F28F1/12Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element
    • F28F1/24Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely
    • F28F1/32Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely the means having portions engaging further tubular elements
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2500/00Problems to be solved
    • F25B2500/01Geometry problems, e.g. for reducing size
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25DREFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D17/00Arrangements for circulating cooling fluids; Arrangements for circulating gas, e.g. air, within refrigerated spaces
    • F25D17/04Arrangements for circulating cooling fluids; Arrangements for circulating gas, e.g. air, within refrigerated spaces for circulating air, e.g. by convection
    • F25D17/06Arrangements for circulating cooling fluids; Arrangements for circulating gas, e.g. air, within refrigerated spaces for circulating air, e.g. by convection by forced circulation
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25DREFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D21/00Defrosting; Preventing frosting; Removing condensed or defrost water
    • F25D21/14Collecting or removing condensed and defrost water; Drip trays
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25DREFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D23/00General constructional features
    • F25D23/003General constructional features for cooling refrigerating machinery
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25DREFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D2323/00General constructional features not provided for in other groups of this subclass
    • F25D2323/002Details for cooling refrigerating machinery
    • F25D2323/0026Details for cooling refrigerating machinery characterised by the incoming air flow
    • F25D2323/00264Details for cooling refrigerating machinery characterised by the incoming air flow through the front bottom part
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25DREFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D2323/00General constructional features not provided for in other groups of this subclass
    • F25D2323/002Details for cooling refrigerating machinery
    • F25D2323/0027Details for cooling refrigerating machinery characterised by the out-flowing air
    • F25D2323/00271Details for cooling refrigerating machinery characterised by the out-flowing air from the back bottom
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25DREFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D2331/00Details or arrangements of other cooling or freezing apparatus not provided for in other groups of this subclass
    • F25D2331/80Type of cooled receptacles
    • F25D2331/803Bottles
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28DHEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D2021/0019Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
    • F28D2021/0068Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for refrigerant cycles
    • F28D2021/007Condensers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F21/00Constructions of heat-exchange apparatus characterised by the selection of particular materials
    • F28F21/06Constructions of heat-exchange apparatus characterised by the selection of particular materials of plastics material
    • F28F21/067Details
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2215/00Fins
    • F28F2215/12Fins with U-shaped slots for laterally inserting conduits
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28FDETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2260/00Heat exchangers or heat exchange elements having special size, e.g. microstructures
    • F28F2260/02Heat exchangers or heat exchange elements having special size, e.g. microstructures having microchannels

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  • Combustion & Propulsion (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)
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Abstract

一种冷饮料和食品的售卖机的冷凝器盘管,包括多个位于相邻的管路之间的平行翅片。为了减少纤维搭接带来污垢的可能性,翅片的间距保持在0.4到0.8英寸的距离。在一个实施例中,管路包括微通道管路,其间没有翅片,微通道管路之间的间距保持在0.75英寸内,以优化热传递性能,同时可使污垢的产生最小化。当没有翅片时,支承结构可设置在微通道管路之间。此外,多排微通道管路设置了单独的入口集管,通过使各排沿横向交错设置,可增强热传递性能,同时可减少污垢形成的可能性。

Description

使用微通道管路的抗污垢冷凝器
技术领域
本发明大体上涉及冷饮料和食品的售卖机,具体地,涉及售卖机的抗污垢的冷凝器盘管。
背景技术
很早就已经通过可分发单瓶饮料的自动售卖机或投币式冷藏容器来销售苏打水或其他软饮料。这些机器一般是单机,电源插入标准出口,并包括各自的制冷回路,带有蒸发器和冷凝器。
这种自我服务方式现在已经扩展到包括其他类型的“电源插入型”饮料和食品售卖机,这些售卖机位于便利店,熟食店,超市和其他零售点。
在这些商店中,冷饮料,如软饮料,啤酒,冷酒器等共同陈列在冷藏售卖机中供顾客自行购买。传统的这种类售卖机一般包括冷藏的绝热的封闭体,形成冷藏产品陈列柜,并具有一个或多个玻璃门。冷藏产品,一般是罐装或瓶装的,单个或6个一组储存在冷藏陈列柜的格架上。要买饮料的顾客打开一个门,从冷藏柜内的格架上取出所要的产品。
这种类型的饮料售卖机设有制冷系统,以便在冷藏陈列柜中提供冷却的环境。这样的制冷系统包括蒸发器盘管,位于形成冷藏陈列柜的绝热封闭体内;和冷却器盘管和压缩机,位于单独设置在绝热封闭体外面的腔室中。冷液体制冷剂循环流过蒸发器盘管,以冷却冷藏陈列柜内的空气。由于空气和通过的进行热交换的蒸发器盘管内的制冷剂之间的热交换,液体制冷剂蒸发,以蒸气形式离开蒸发器盘管。气相的制冷剂然后在压缩机盘管中压缩为高压,并由于压缩过程被加热到较高温度。较高温度的高压蒸汽然后循环通过冷凝器盘管,在冷凝器与环境空气进行热交换,空气是被可操作地连接到冷凝器盘管的风扇抽或吹到冷凝器盘管的。结果是,制冷剂受到冷却并冷凝回到液相,然后通过膨胀装置,液体制冷剂的压力和温度降低后,循环回到蒸发器盘管。
在传统实践中,冷凝器盘管包括多个管路,带有横过环境空气流的流动路径延伸的翅片,环境空气流被吹或抽过冷凝器盘管。可操作地连接到冷凝器盘管的风扇使得局部环境的环境空气通过冷凝器盘管。美国专利3,462,966公开了一种冷藏玻璃门售卖机,具有带交错排翅片管的冷凝器盘管,和设置在冷能器盘管上游的相关风扇,可将空气吹过冷凝器管路。美国专利4,977,754公开了一种冷藏玻璃门售卖机,具有带同轴翅片管排的冷凝器盘管,和设置在冷凝器的下游的相关风扇,可将空气抽过冷凝器管路。
这种自备式售卖机的一个问题是其通常所在的区域有拥挤的人流,一般会带来外面的碎屑和污垢。这些污垢又暴露于冷凝器盘管,盘管必须暴露于附近的空气流,很容易受到空气方面的污染。这些污垢,累积的灰尘,脏物和油迹损害了制冷性能。当冷凝器盘管带有污垢,压缩机的制冷剂压力上升,导致系统效率下降和带来压缩机故障。此外,这些产品通常用于不可能进行周期性清洁的地方。
这些冷凝器盘管的普通结构是管路和翅片设计,其中制冷剂流过的多个蜿蜒管路周围是正交延伸的翅片,通过风扇使冷却空气流过翅片。一般地,管路和翅片密度越大,盘管冷却制冷剂的性能也越高。但是,管路和翅片密度越高,就越容易受到累积的灰尘和纤维的污染。
美国专利申请No.10/421,575提出了一种通过去除翅片和依靠传统管路的方式来解决这个问题,该专利转让给提出本申请的受让人,该专利在本发明中参考引用。作为2002年4月30日提交的临时专利申请No.60/376,486的部分继续申请的,该专利转让给提出本申请的受让人,美国专利申请No.(PCT/US03/12468)提出的另一解决方法是,在空气流的方向上选择性交错连续的管路排。该专利内容在本文中参考引用。
发明内容
简单地,根据本发明的一个方面,带有微通道管路的冷凝器盘管代替管路和翅片冷凝器盘管,微通道管路的数量比前圆管的数量多,但管路之间的间隙比较大,使得来自空气的污垢不大可能产生。
根据本发明的另一方面,这样的微通道制冷剂管路能够在与传统圆管冷凝器相比更少量的制冷剂下操作,使得额外管路表面不会显著增加注入制冷剂的要求,额外管路表面是为使用较少翅片而作的补偿。
在本发明的另一方面,微管冷凝器盘管的翅片密度减少到这样的水平,可基本上消除翅片之间纤维的搭接,使污垢积聚的发生大量减少或消除。如果翅片密度减少到微通道管路之间很少或没有支撑的程度,则需设置支撑结构于相邻管路之间的间隙,以防止移动和/或损坏。
根据本发明的另一方面,为了在减少管路和翅片密度的情况下提供足够的热交换表面积,多排微通道管路可设置成,各排具有其自己的集管。为了得到更高的热交换效率且不会带来更多污垢,管路排是交错的,使得下游排的管路定位成基本位于上游排的管路之间。
下面介绍的附图中显示了优选实施例,但是,可实施其他各种改进和变化的结构,这未脱离本发明的真实精神和范围。
附图说明
图1是根据现有技术的冷藏饮料售卖机的透视图;
图2是显示冷藏饮料售卖机的蒸发器和冷凝器部分的侧视截面图;
图3是根据本发明的一个实施例的冷凝器盘管的透视图;
图4是显示管/翅片密度和污垢发生之间关系的图表;
图5是根据本发明的冷凝器盘管的可选实施例的透视图;
图6是根据本发明的一个实施例的支撑结构的侧视截面图;
图7是前视图;
图8是本发明的显示出具有微通道管路交错排的可选实施例。
具体实施方式
参考图1和图2,显示出冷藏冷饮料售卖机,其一般用数字10表示。饮料售卖机10包括封闭体20,形成了冷藏陈列柜25;和单独的设置在外部的并与冷藏陈列柜25绝热的腔室30。腔室30可设置在冷藏陈列柜25的下部,如图所示,或腔室可设置在陈列柜25的上方。压缩机40,冷凝器盘管50,冷凝水盘53,和相关的冷凝器风扇和马达60位于腔室30内。安装板44可设置在压缩机40,冷凝器盘管50和冷凝器风扇60下面。安装板44最好可滑动地安装在腔室30内,以便可选择地进出腔室30,有助于安装在其上的制冷装置进行维修。
冷藏陈列柜25由封闭体20的绝热后壁22,封闭体20的一对绝热侧壁24,封闭体20的绝热顶壁26,封闭体20的绝热底壁28和封闭体20的绝热前壁34形成。绝热材料36(用环形线显示)设置在形成冷藏陈列柜25的壁上。饮料产品100,如单个饮料罐或饮料瓶或6个饮料的组,陈列在格架70上,格架以常用方式安装在冷藏陈列柜25上,如根据下一个购买的方式,其显示于美国专利4,977,754,此专利的全部内容在本文参考引用。绝热封闭体20设有前壁34上的入口35,通向冷藏陈列柜25。如果需要,门32,如图示实施例所示,或不止一个门,可设置以覆盖入口35。应当知道,本发明也可应用于入口没有门的饮料售卖机。接近饮料产品进行购买的顾客只需打开门32,接近冷藏的陈列柜25,以选择需要的饮料。
蒸发器盘管80设置在冷藏陈列柜25,如靠近顶壁26。如图2所示,可设置蒸发器风扇和马达82以便在冷藏陈列柜内使空气循环通过蒸发器80。但是可不设置蒸发器风扇,因为空气循环通过蒸发器可依靠自然对流。当循环空气通过蒸发器80时,以传统的方式与蒸发器盘管中循环的制冷剂进行热交换,因此冷却。冷却的空气离开蒸发器盘管80,以通常方式向下流到柜内,通过设置在格架70上的产品100,然后向上抽回又通过蒸发器。
制冷剂通过压缩机40以通用方式在蒸发器80和冷凝器50之间循环通过构成冷却回路(未显示)的与压缩机相连的制冷管线,冷凝器盘管50和蒸发器盘管80可制冷剂流通。如前面所指出的,冷液体制冷剂循环通过蒸发器盘管80以冷却冷藏陈列柜25内的空气。由于空气和通过蒸发器盘管80的制冷剂进行热交换,液体制冷剂蒸发,以气相离开蒸发器。气相的制冷剂然后在压缩机40压缩到高压,并因为压缩过程被加热到高温。热的高压气相制冷剂然后循环通过冷凝器盘管50,与环境空气进行热交换,环境空气被冷凝器风扇60抽或吹过冷凝器盘管50。
现在参考图3,根据本发明,图2的管和翅片冷凝器盘管50被110表示的微通道冷凝器盘管代替。不采用圆管,排115的多个微通道管路111平行设置且各端部分别连接到入口和出口集管113,114,微通道管路有多个沿长度延伸的平行通道112。入口管路116设置在入口集管113,出口管路117设置在出口集管114。操作中,热的高温制冷剂蒸气从压缩机流到入口管路116,通过各微通道112分配,流过各微通道管路111,冷凝成液相。液相的制冷剂然后流到出口集管114,经出口管路117流到膨胀机构。
为了增加盘管110的热交换能力,多个翅片118可设置在相邻微通道管对之间。这些翅片最好正交对准微通道管路111,平行于通过微通道冷凝器盘管110的空气流的方向。相邻翅片之间的横向间隔为尺寸W。
微通道管路111的冷凝器盘管比传统的圆管优越在于单位体积可以有更大的表面积。即,多个小管可提供比一个大管更多的外表面。为了理解可比较单个3/8英寸(8毫米)管和5毫米管。5毫米管的外表面积-体积比是0.4,其大于8毫米管的0.25的外表面积-体积比。
使用更多数量的较小管而不是较少数量的大管的一个缺点是,其实现成本更高。但是,制造具有多个通道的微通道管路的技术已经发展到与制造和实现热交换器盘管的圆管相比更经济的程度。
微通道管路的另一优点是具有流线型,所以导致较小的压力降和较低噪音水平。即流过较窄的微通道的空气阻力比流过较大圆管的空气的阻力小很多。
现在考虑空气侧污垢的问题,污垢由冷凝器盘管的相邻管路和/或相邻翅片之间累积的灰尘,脏物和油污造成,申请人已经认识到,这些污垢出自相邻管路之间或相邻翅片之间的细长纤维的搭接。即很小颗粒可通过盘管的通道,除非通道一定程度上被其间的纤维堵塞。当搭接的纤维位于相邻的翅片或相邻的管路之间时,则小颗粒容易收集到该纤维并聚集,最终导致通道形成污垢。为了防止和减少污垢的发生,因此需要了解到形成污垢的方式受到盘管的结构的影响。认识到这点,本申请人进行了实验,以确定管路间距和翅片间距的变化如何影响发生污垢的可能性,结果在图4显示。
进行了现场分析以确定最可能使冷凝器盘管出现污垢的材料类型,发现棉花纤维是污垢的重要原因,污垢通常始于相邻翅片之间或相邻管路之间的细长纤维的搭接。因此,进行了实验分析以确定在棉花纤维的环境下当翅片的间距选择变化时冷凝器盘管形成污垢的倾向。将多个标准设计的带有特定间距的圆管和板翅片的热交换器暴露于天然棉花纤维的环境,测试各自的出现污垢的倾向。具有每英寸7个翅片或相邻翅片之间的翅片间距为0.14英寸的热交换器任意地确定污垢优度参数(FGP)为1。这在图4所示的图表位于点A。
当翅片间距增加,FGP的相关增加基本是线性地到达点B,这时的间隔是0。4英寸,FGP是1.5。在点C,相互关系仍接近线性,其间距是0.5英寸,相关的FGP是2。这意味着热交换器的污垢发生2倍“优”于点A的热交换器。
当间距增加超过0.50间距,可以看到FGP的增加开始基本上脱离线性关系,如点D所示,间距为0.75英寸,其接近渐进线关系。因此,可得出结论,翅片间距同样可保持为0.75英寸,或更大,如果希望有最大的FGP。可认识到,在这些较高间距参数的点,暴露面积减少,因此热交换能力下降。因此,希望保持足够的翅片间距,以得到足够高的FGP,同时保持足够的密度以提供希望数量的表面积。例如,在点E,得到了足够高的6的FGP,相邻翅片之间的翅片间距为0.70英寸。
尽管上面讨论的实验数据涉及圆管热交换器的翅片间距,申请人相信相同的性能特征对图3所示的微通道管路热交换器的翅片间距也适用,因为涉及细长纤维连接的原理在各种情况下都是基本相同的。此外还认识到,通过图3所示的微通道管路设置可以完全取消翅片,或减少其数量,使得只要简单地提供微通道管路之间的支撑,同时增加微通道管路的密度,得到希望的表面积进行热交换。这样的热交换器在图5显示。
在图5的实施例,可看到已经取消翅片,微通道管路111只是简单地悬臂置于入口集管113和出口集管114之间,如图所示。通过这样设置,结构非常简单,翅片的成本也没有了。但是,翅片的表面积带来的热传递的好处也丧失掉。因此,有必要增加微通道管路111的密度,使得其间的距离,如图5中L所示,减少很多。在这方面,可考虑上面的讨论,即翅片的间距也相关于微通道管路111的间距。就是说,对于0.75英寸的间距L,应当有很少或没有污垢发生,但当翅片密度增加,污垢优度参数(FGP)将减少,或用另一种方式表示,污垢发生的可能性将增加。
对于图5所示的完全取消翅片,有必要提供相邻微通道管路111之间的某些支撑,使得在热交换器制造期间和最终产品上,微通道管路111受到限制不能从相对平行位置下沉。这样的支撑在图6和图7中的118处显示。在图6中,显示出左侧的位于未安装位置的支撑件118带有多个齿119,然后位于右侧的安装位置。图7显示出位于安装位置的三个这样的支承件118的侧视图和前视图。这样的支承件118可用导热材料制造,以便不仅提供支撑,还可用作与翅片同样方式的导体。但是,具有如图所示的大间隔,导致不能显著增加导热表面积,翅片的有益作用变得很小。因此,支承件可用其他材料如塑料材料制造,其提供了必要的支撑,但未对热传递的功能有所贡献。这里,支承件118的间隔很清楚要足够,使得支承件之间的横向间隔不会有利于纤维搭接,否则会造成污垢。只有相邻微通道管路之间的距离L决定了其间的纤维是否搭接。参考图5实施例进行的讨论因此涉及到图6和图7的支承件实施例。
对于上面讨论的取消翅片,还需要考虑的另一个作用是,随着产生的热交换表面积减少,和微通道管路的密度相应增加,还有足够的热交换表面积以实现必要的性能吗?假设因为上面讨论的性能特性,相邻微通道管路之间的间距L保持在大约0.75英寸,使得微通道管路的数量可能不足够产生希望的热交换数量。图8显示了克服这个问题的方法,其中第二排121的微通道管路122显示出带有集管123。这样可有效地加倍热交换器的表面积,且不会显著地增加微通道管路之间出现污垢的问题。尽管两排微通道管路115,121可沿空气流的方向一个排列在另一排后面,但通过两排交错使第二排的管路122基本设置在第一排115的管路111之间和下游,可改善空气流动特性。通过这样设置,抗污垢参数的控制参数仍是距离L,因为其不仅是第一排115的各管111之间的距离,还是第二排121的管122之间的距离。即通过这样的交错关系,纤维搭接第一排115的管路111和第二排121的管路122之间间隙的可能性非常低。
当然,应当知道多排管路以交错关系设置,使得第三排极大可能与第一排对准,第四排极可能对准第二排。此外,污垢优度参数不会显著改变,因为控制参数仍是任何单排的管路之间的距离L
尽管本发明已经具体显示和介绍了优选的和可选择的实施例,其如附图所示。所属领域的技术人员应当知道,可以实施各种细节的变化,这未脱离权利要求所限定的发明真实精神和范围。

Claims (17)

1.一种冷藏售卖机,包括:
封闭体,具有前壁,其一部分形成冷藏陈列柜,所述前壁设有进入口,可接近冷藏陈列柜;
蒸发器盘管,设置成可操作地连接到所述冷藏陈列柜;
腔室,与所述冷藏陈列柜绝热;
冷凝器盘管,设置在所述腔室内;
冷凝器风扇,设置在所述腔室内,使空气在所述冷凝器盘管和所述冷凝器上循环流动;和
压缩机,设置在所述腔室内,可使制冷剂流体连通所述蒸发器盘管和所述冷凝器盘管,使制冷剂循环通过所述蒸发器盘管和所述冷凝器盘管;
所述冷凝器盘管具有多个制冷剂传输管路,在正交空气流方向的平面基本平行对齐;和多个翅片,可热传递地连接各管路,在正交于空气流方向的平面上基本平行;
其中,所述多个翅片的相邻翅片之间间隔范围在0.4到0.8英寸。
2.根据权利要求1所述的冷藏售卖机,其特征在于,所述多个翅片的相邻翅片之间间隔范围为0.7到0.8英寸。
3.根据权利要求2所述的冷藏售卖机,其特征在于,所述多个翅片的相邻翅片之间间隔大致0.75英寸。
4.根据权利要求1所述的冷藏售卖机,其特征在于,所述多个管路是微通道管路,各自设有多个纵向延伸通道,通道端部流体连通,可接收来自集管的制冷剂蒸气流。
5.根据权利要求4所述的冷藏售卖机,其特征在于,所述微通道管路的相邻管路之间间隔范围在0.4到0.8英寸。
6.根据权利要求4所述的冷藏售卖机,其特征在于,所述微通道管路的相邻管路之间间隔范围在0.7到0.8英寸。
7.根据权利要求6所述的冷藏售卖机,其特征在于,所述微通道管路的相邻管路间隔开大致0.75英寸。
8.一种冷藏售卖机,包括:
封闭体,具有前壁,其一部分形成冷藏陈列柜,所述前壁设有进入口,可接近冷藏陈列柜;
蒸发器盘管,设置成可操作地连接到所述冷藏陈列柜;
腔室,与所述冷藏陈列柜绝热;
冷凝器盘管,设置在所述腔室内;
冷凝器风扇,设置在所述腔室内,使空气在所述冷凝器盘管上循环流动;和
压缩机,设置在所述腔室内,可使制冷剂流体连通所述蒸发器盘管和所述冷凝器盘管,使制冷剂循环通过所述蒸发器盘管和所述冷凝器盘管;
所述冷凝器盘管具有至少一个集管,可接受来自所述压缩机的制冷剂蒸气;并具有多个微通道管路,各自设有多个纵向延伸的通道,其端部流体连通,可接收来自至少一个集管的制冷剂蒸气,所述多个管路具有通常是平面的侧面,一般对准空气流的方向,相邻管路之间的间隔范围是0.4到0.8英寸。
9.根据权利要求8所述的冷藏售卖机,其特征在于,所述微通道管路的相邻管路之间间隔范围为0.7到0.8英寸。
10.根据权利要求9所述的冷藏售卖机,其特征在于,所述微通道管路的相邻管路之间间隔开大致0.75英寸。
11.根据权利要求8所述的冷藏售卖机,其特征在于,所述冷凝器盘管具有多个翅片,可热传递地连接各微通道管路;所述翅片间隔开,相邻翅片之间的距离在0.4到0.8英寸的范围。
12.根据权利要求11所述的冷藏售卖机,其特征在于,所述多个翅片的两个相邻翅片之间的间隔距离为0.7到0.8英寸。
13.根据权利要求12所述的冷藏售卖机,其特征在于,所述翅片间隔开的距离大致为0.75英寸。
14.根据权利要求8所述的冷藏售卖机,其特征在于,所述冷凝器盘管包括第二多个微通道管路,带有相连的集管,所述第二多个微通道管路设置在所述第一多个微通道管路的下游。
15.根据权利要求14所述的冷藏售卖机,其特征在于,所述第二多个微通道管路与对齐的所述第一多个微通道管路沿横向交错设置。
16.根据权利要求8所述的冷藏售卖机,其特征在于,所述冷凝器盘管具有入口集管和出口集管,各自连接到所述多个微通道管路。
17.根据权利要求8所述的冷藏售卖机,其特征在于,包括至少一个支承件,其具有多个间隔开的附件,各自设置在相邻微通道管路之间以提供支承。
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CN1946318B (zh) 2010-12-08
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