涡旋压缩机_翻译

1、译文：涡旋压缩机涡旋压缩机的运作涡旋压缩机（也叫螺旋式压缩机，涡旋泵，涡旋真空泵）是一个压缩空气或制冷的设备。它作为汽车增压器（人们熟知的滚动式增压器）和真空泵而用于空气调节设备。反向操作的涡旋压缩机被称为滚动扩张机，可用于从事流体的扩张机械工作。许多住宅和热泵中央空调系统和一些汽车空调系统已经采用涡旋压缩机代替了更为传统的旋转式，往复式和摆动板压缩机。历史：Léon Creux在1905年在法国和美国申请了涡旋压缩机专利（专利号801182）。Creux最早提出蒸汽机为旋转压缩机的概念，但这一时期的金属铸造技术不够先进，而且要使涡旋压缩机有效发挥作用需要很严格的公差，所以不能兴建工

2、作原型。第一个可行的涡旋压缩机直到二战结束后才出现在市场上，当时高精密机床刚被获准建设。它们直到20世纪80年代初才被认为是为空调生产的产品。设计：涡旋压缩机使用两个交叉滚动到泵，压缩，或施加压力，如液体和气体的流体。叶片几何可能是渐开线，阿基米德螺旋线，或混合曲线。通常一个卷轴是固定的，同时其它轨道没有偏心旋转，从而捕捉和抽水或压缩流体之间的滚动槽腔。另一个产生压缩动作的方法是卷轴共同旋转，虽然作同步运动，但与旋转中心偏移。如果一个卷轴在轨道上运行，那么相对运动就是一致的。另一个变化，是灵活的管材如阿基米德螺旋泵作为一个蠕动泵，就像牙膏管一样的原理。里面填充润滑油，以防止泵管的磨损和外部散热

3、，并使用增强管，通常被称为“软管”。 这种泵类通常被称为一个“软管泵”。此外，由于没有活动与流体，蠕动泵是制造成本低廉的部件。他们缺乏阀门，密封件和腺体，使他们保持相对便宜，而一软管或管道的使用使它与其它类型的泵相比保持了低成本的优势。应用：空调压缩机；真空泵；汽车增压器应用，如大众汽车公司的G - Lader。相对于其它泵的工程比较与一些传统压缩机的应用相比，这些设备以操作灵活、低噪音、可靠而出名。不像活塞，在轨道滚动的质量完全可以抵消，质量小可以减少震动。然而，确保正确的轨道滚动位置的Oldham耦合质量并不能平衡，因此它的存在仍然影响了涡旋压缩机的固有震动。卷轴的气体流程更加连续。此外，

4、缺少死角会增加容积效率。旋转和脉冲流与旋转式压缩机一个旋转和往复式压缩机一个半旋转相比，压缩过程中发生了约2至2.5的曲轴旋转。滚动排放和抽吸过程中会出现一个完整的旋转，而不是一个半吸过程中的往复旋转以下，超过四分之一的放电过程往复旋转少。更稳定的收益率得益于较低的气体流量脉动，低音效，低振动，和更有效的流动。阀门：涡旋压缩机没有吸气阀有，但根据不同的应用需求来确定要不要排气阀。建立有活力的排放阀的使用在高压比的应用和制冷典型中更加突出。空调涡旋通常没有动力阀，活力排放阀的使用提高了涡旋压缩机的效率，工作压力的比例，远高于内置压力的压缩机的比例。但是，如果压缩机设计为一个单一的工作点附近，然后

5、滚动压缩机其实可以有效地解决此问题，如果没有目前的动态排放阀（因为有小的额外排放流量与排放相关的损失存在于排放阀中）。效率：当压缩机设计在一个选定点操作时，涡旋压缩机的等熵效率比典型的往复式压缩机高。这是因为它们没有介绍更多节流损失的动力阀。然而，与高压比操作的往复式压缩机相比，不具有排气阀的涡旋压缩机的效率开始下降。这是一个所谓的下压损失，在高压力的正排量压缩机不具有一个动态的排放阀发生比率运作的结果。对发展二氧化碳制冷行业系统操作有一个工业上的趋势。虽然二氧化碳没有臭氧那么直接致使全球变暖的潜力。在不必在加强与大型换热器系统的大量支出，注汽方案，扩展器等的情况下，与其它传统制冷剂相比，使用

6、二氧化碳来实现理想的循环利用非常困难。有充足二氧化碳的情况下，往复式压缩机是最佳选择，因为这种应用不容易设计出有效、合理的涡旋压缩机。输送流体时，滚动压缩的过程几乎达到百分之百的容积率。吸气过程中创建了自己的容积，将压缩过程和排泄过程分离开来了。相比之下，往复式压缩机留了少量压缩气体在气缸里面，因为让活塞触到顶部或阀板是不实际的，最后一个周期的残存气体接着以吸气为目的占据空间。能力（即容积效率）的下降取决于放电发生率较高，以减少吸入压力和排出压力。可靠性：涡旋压缩机比往复式压缩机的移动部件更少，往复式压缩机在理论上应该提高可靠性。据Copeland一个大型涡轮机生产厂家说，涡旋压缩机比往复式压

7、缩机要少70%的运动部件。2006年，食品服务设备的主要制造商Stoetling，选择改变往复滚动压缩冰淇淋机的设计。通过测试，他们发现在涡旋压缩机设计具有更好的可靠性和能源效率的运作。但是，许多应用程序依靠往复式制冷压缩机，这似乎更比涡旋压缩机这些应用可靠。这些应用包括超市的冷藏卡车和拖车的申请。漏涡：旋压缩机更容易引入碎片，因为任何碎片需要通过至少两个封闭压缩槽腔，没有径向或轴向运作的卷轴更容易受到外来物体的损害。然而，对液体流动来说，卷轴没有吸气阀是该往复式压缩机中最脆弱的地区之一。涡旋压缩机在压缩机内使用不同的保护方法来处理不同状况。有的在压缩过程中的不同点设计阀门，以减轻压缩元素的压

8、力。往复式压缩机即使运行在任何一个方向，仍然正常运作，而一个涡旋压缩机必须在一个方向旋转，只是为了正常运行。这在极短的功率损耗时期非常重要，当涡旋压缩机运行可能会被迫向后排放压力。只有单相涡旋压缩机将继续在电源后反向运行。如果发生这种情况，涡旋压缩机将停止抽水。在反向运行的几分钟内涡旋压缩机一般不会损坏压缩机。与单相压缩机相比，三相压缩机在很短的电源中断中将恢复前进的方向。不过，重要的是在初始安装三相压缩机时恰当地安放线。如果安装过程中弄反了极性，三相压缩机就会反向运行，如果长时间未被发现就会导致压缩机损坏。减轻对启动压缩机淹没操作的方法之一，是在压缩机正转之前让它反转几分钟。启动时的短期反向

9、运行将会排出一些液体，以及由预热的热量消耗汽车曲轴箱中储存的任何液体。排出的液体和预热曲轴箱中的任何液态制冷剂在开始之前，前进方向的正常运行大大缓解了启动淹没问题。大小：涡旋压缩机往往非常紧凑，运行平稳，所以不需要弹簧悬挂。这使他们有非常小的壳罩从而降低整体成本，但也导致自由体积较小。这是在液体处理方面的弱点。其相应的强度是在缺乏吸气阀的动作失败的驱动系统可能提出的问题最有可能有所增强。因此，滚动机制本身更加宽容液体的摄入，但同时更容易体验到它的运作。涡旋压缩机的小体积和安静地操作使得它可以置入高密度的电脑，像IBM大型机。涡旋压缩机还简化了管路的设计，因为它们不需要冷却剂的主要外部连接。局部

10、加载：直到最近，当供电时，涡旋压缩机才满载运行。调制的能力是实现滚动外集。为了实现部分负荷，工程师会绕过制冷剂（称为热气体旁路），更改马达转速，或提供多种压缩机让它们依次出现。这些方法都有一定缺点。热气旁通短周期的正常制冷循环，并允许一些压缩气体直接返回到压缩机而不做任何有益的工作。这种做法降低了整体系统的效率。一个双速电机需要更多的电气连接和交换，增加成本，并可能不得不停止转换。变速电机需要额外的设备提供整个所需频率范围内的电力。压缩循环需要更多的压缩机，会很昂贵。此外，该系统的一些压缩机可能会非常小，以精确的温度控制过程。最近已制造出在单一压缩机内能提供部分负荷能力的涡旋压缩机。这些压缩机

11、可以在运行过程中改变容量。一种方法是推迟压缩开始时间。压缩的开始阶段是发泄回吸力。这减少了被压缩的液体量，在压缩过程的其余部分是正常的。爱默生制作了一种能够按照需要改变制冷剂流动的涡旋压缩机，而并不是将卷轴固定在一起，这些卷轴可以在一定时期内移动。随着卷轴移动，汽车继续向前运动，但当涡旋压缩机不抽水的时候，这些卷轴失去了压缩制冷的能力，从而降低电机功率。由交替的两个不同的工作状态：在负载状态和卸载状态。螺线管在使用轴向原则时扩大了旋转滚动和/或固定滚动卷轴。该控制器修改了加载时间和卸载时间，与压缩机的负荷能力要求相匹配。原文：Scroll compressor窗体底端Operation of

12、a scroll compressorA scroll compressor (also called spiral compressor, scroll pump and scroll vacuum pump) is a device for compressing air or refrigerant. It is used in air conditioning equipment, as an automobile supercharger (where it is known as a scroll-type supercharger) and as a vacuum pump.A

13、scroll compressor operating in reverse is known as a scroll expander, and can be used to generate mechanical work from the expansion of a fluid.Many residential central heat pump and air conditioning systems and a few automotive air conditioning systems employ a scroll compressor instead of the more

14、 traditional rotary, reciprocating, and wobble-plate compressors.History：Léon Creux first patented a scroll compressor in 1905 in France and the US (Patent number 801182). Creux originally invented the compressor as a rotary steam engine concept, but the metal casting technology of the period w

15、as not sufficiently advanced to construct a working prototype, since a scroll compressor demands very tight tolerances to function effectively. The first practicable scroll compressors did not appear on the market until after World War II,when higher-precision machine tools permitted their construct

16、ion. They were not commercially produced for air conditioning until the early 1980s。Design：A scroll compressor uses two interleaved scrolls to pump, compress, or pressurize fluids such as liquids and gases. The vane geometry may be involute, archimedean spiral, or hybrid curves. Often, one of the sc

17、rolls is fixed, while the other orbits eccentrically without rotating, thereby trapping and pumping or compressing pockets of fluid between the scrolls. Another method for producing the compression motion is co-rotating the scrolls, in synchronous motion, but with offset centers of rotation. The rel

18、ative motion is the same as if one were orbiting.Another variation, is with flexible (layflat) tubing where the archimedean spiral acts as a peristaltic pump, that operates on much the same principle as a toothpaste tube. They have casings filled with lubricant to prevent abrasion of the exterior of

19、 the pump tube and to aid in the dissipation of heat, and use reinforced tubes, often called 'hoses'. This class of pump is often called a 'hose pump'. Furthermore, since there are no moving parts in contact with the fluid, peristaltic pumps are inexpensive to manufacture. Their lack

20、 of valves, seals and glands makes them comparatively inexpensive to maintain, and the use of a hose or tube makes for a low-cost maintenance item compared to other pump types.ApplicationsAir conditioner compressor Vacuum pump Superchargers for automobile applications, e.g. Volkswagen's G-Lader.

21、 Engineering comparison to other pumpsThese devices are known for operating more smoothly, quietly, and reliably than conventional compressors in some applications. Unlike pistons, the orbiting scrolls mass can be perfectly counterbalanced, with simple masses, to minimize vibration. However, Oldham

22、coupling mass that ensures proper position of the orbiting scroll cannot be balanced and thus its presence still results in inherent scroll compressor vibration. The scrolls gas processes are more continuous. Additionally, a lack of dead space gives an increased volumetric efficiency.Rotations and p

23、ulse flow：The compression process occurs over approximately 2 to 2½ rotations of the crankshaft, compared to one rotation for rotary compressors, and one-half rotation for reciprocating compressors. The scroll discharge and suction processes occur for a full rotation, compared to less than a ha

24、lf-rotation for the reciprocating suction process, and less than a quarter-rotation for the reciprocating discharge process. The more steady flow yields lower gas pulsations, lower sound, lower vibration, and more efficient flow.Valves：Scroll compressors never have a suction valve, but depending on

25、the application may or may not have a discharge valve. The use of a dynamic discharge valve is more prominent in high pressure ratio applications, typical of refrigeration. Typically, an air-conditioning scroll does not have dynamic valves. The use of a dynamic discharge valve improves scroll compre

26、ssor efficiency over a wide range of operating conditions, when the operating pressure ratio is well above the built-in pressure ratio of the compressors. However, if the compressor is designed to operate near a single operating point, then the scroll compressor can actually gain efficiency around t

27、his point if there is no dynamic discharge valve present (since there are small additional discharge flow losses associated with the presence of the discharge valve). Efficiency：The isentropic efficiency of scroll compressors is slightly higher than that of a typical reciprocating compressor when th

28、e compressor is designed to operate near one selected rating point. The scroll compressors are more efficient in this case because they do not have a dynamic discharge valve that introduces additional throttling losses. However, the efficiency of a scroll compressor that does not have a discharge va

29、lve begins to decrease as compared to the reciprocating compressor at higher pressure ratio operation. This is a result of so called under-compression losses that occur at high pressure ratio operation of the positive displacement compressors that do not have a dynamic discharge valve.There is an in

30、dustry trend toward developing systems operating on CO2 refrigerant. While CO2 has no ozone depletion potential and essentially no direct global warming potential, it is very difficult to achieve a reasonable cycle efficiency using CO2 as compared to other conventional refrigerants, without having s

31、ubstantial expenditures on enhancing the system with large heat exchangers, vapor injection options, expanders, etc. In case of CO2, the reciprocating compressor appears to offer the best option, as it is difficult to design an efficient and reliable scroll compressor for this application.The scroll

32、 compression process is nearly one hundred percent volumetrically efficient in pumping the trapped fluid. The suction process creates its own volume, separate from the compression and discharge processes further inside. By comparison, reciprocating compressors leave a small amount of compressed gas

33、in the cylinder, because it is not practical for the piston to touch the head or valve plate. That remnant gas from the last cycle then occupies space intended for suction gas. The reduction in capacity (i.e. volumetric efficiency) depends on the suction and discharge pressures with greater reductio

34、ns occurring at higher ratios of discharge to suction pressures.Reliability：Scroll compressors have fewer "moving parts" than reciprocating compressors which, theoretically, should improve reliability. According to Copeland, a big manufacturer of scroll compressors, scroll compressors have

35、 70 percent fewer moving parts, while comparing with the conventional reciprocating compressors.In 2006 a major manufacturer of food service equipment, Stoetling, chose to change the design of one of their soft serve ice cream machines from reciprocating to scroll compressor. They found through test

36、ing that the scroll compressor design delivered better reliability and energy efficiency in operation. However, many refrigeration applications rely on reciprocating compressors, that appear to be more reliable in these applications than scroll compressors. These applications include supermarket ref

37、rigeration and truck trailer applications.Vulnerabilities：Scroll compressors are more vulnerable to introduced debris, as any debris need to pass through at least two closed compression pockets. The scrolls that operate without radial and/or axial compliance are even more prone to the damage caused

38、by foreign objects. However, scrolls do not have suction valves, which is one of the most vulnerable parts of the reciprocating compressor to liquid flooding.Scroll compressors utilize different methods of protection inside the compressor to handle difficult situations. Some scroll designs utilize v

39、alves at different points in the compression process to relieve pressure inside the compression elements.A reciprocating compressor can run in either direction and still function properly, whereas a scroll compressor must rotate in one direction only in order to function. This can be important durin

40、g extremely short periods of power loss when a scroll compressor may be forced to run backward from the pressure in the discharge line. Only single phase scroll compressors would continue to run in reverse after the power comes back on. If this happens, the scroll compressor will stop pumping. Runni

41、ng scroll compressor in reverse for several minutes would normally not damage the compressor. The three phase compressor, as compared to single phase compressors, would revert to operation in a forward direction at the end of a short power interruption. However, it is important to properly wire the

42、three phase compressor during the initial installation. If during the installation the polarity is inadvertently reversed then the three phase compressor would run backward and the damage to the compressor may result if it goes unnoticed for long period of time. One of the ways to mitigate the flood

43、ed operation of the compressor on start up, is to actually run the compressor for several minutes in the reverse direction before turning the compressor in the forward direction. The short reverse run on the start up would expel any liquid accumulated inside the compressor pumping element back into

44、the crankcase, as well as preheat the liquid stored in the crankcase by dissipated motor heat. Expelling the liquid from the pumping element and preheating any liquid refrigerant in the crankcase prior to initiating the normal run in the forward direction significantly alleviates problems with the f

45、looded start.Size：Scroll compressors tend to be very compact and smooth running and so do not require spring suspension. This allows them to have very small shell enclosures which reduces overall cost but also results in smaller free volume. This is a weakness in terms of liquid handling. Their corr

46、esponding strength is in the lack of suction valves which moves the most probable point of failure to the drive system which may be made somewhat stronger. Thus the scroll mechanism is itself more tolerant of liquid ingestion but at the same time is more prone to experience it in operation. Small si

47、ze of a scroll compressor and quiet operation allows for the unit to be built into high power density computers, like IBM mainframes. Scroll compressors also simplify the piping design, since they require no external connection for the primary coolant.Partial loading：Until recently, scroll compresso

48、rs operated at full capacity when powered. Modulation of the capacity was accomplished outside the scroll set. In order to achieve part-loads, engineers would bypass refrigerant (called hot-gas bypass), vary motor speed, or provide multiple compressors and stage them on and off in sequence. Each of these methods has drawbacks:Hot gas bypass short-cycles the normal refrigeration cycle and allows some of the compressed gas to return d