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一、例子3二、Input输入模块41、problem definition问题定义模块41.1、description基本描写52、 application options(程序运行环境选择)52.1、Hot side application(热流运行环境)62.2、Condensation curve冷凝曲线62.3、Condenser type冷凝器类型62.4、Cod side application(冷流运行环境)72.5、Location of hot fluid流程安排(热流位置)72.6、Program mode(程序模式选择:设计、优化、模拟)73、process data物流参数输入83.1、Fluid name(流体名称)83.2、Fluid quantity, total(热或冷流体总流速)83.3、Temperature冷热流体进出口温度83.4、Operating Pressure(absolute) 绝对操作压力93.5、Heat exchanged交换热量93.6、allowable pressure drop允许的压力降93.7、fouling resistance污垢热阻104、热平衡计算环境115、 Physical Property Data物理特性数据11(1)Property Option(特性程序选择一般默认)12(2) Hot Side Composition热物质组成(若未知可不输)12(3)Hot Side Properties(热物流特性)13(4)cold side composition(冷物流组成与前热物流组成一样)13(5) cold side properties(冷物流特性)136、 Exchanger Geometry(结构参数)136.1 exchanger Type(换热器类型)14(1)Front head type(换热器前端管箱)14(3)Rear head type(后端结构)17(4)exchanger position(换热器水平还是垂直安装)18(5)cover密封(盖子)面类型(工艺计算没必要提供)18(6)Tubesheet type管板形式18(7)Tube to tubesheet joint管子与管板的连接(工艺不关键)196.2 Tubes(换热管)19(1)Tube type(管子类型)19(2)Tube outside diameter(管子外径)20(3)Tube wall thickness(管子壁厚)21(4)Tube wall roughness(管子粗糙度)21(5)Tube wall Specification(管子壁厚计算指定)21(6)Tube pich管心距22(7)Tube material管子材质22(8)Tube pattem换热管的排列22(9)翅片管相关数据23(a)Fin density翅片密度23(b)Fin height翅片高度24(c)Fin thickness翅片厚度24(d)Surface area per unit length每单位管长的表面积24(e)Outside/Inside surface area ratio外内表面积比24(f)Twisted Tape Ratio扭带比24(g)Twisted Tape Width纽带宽24(h)Tapered tube ends for knockback condensers246.3 Bundle结构参数限定25(1)shell entrance/exit壳体入口/出口25(2)Provide disengagement space in shell (pool boilers only) 提供气体空间(只对锅炉使用)26(3)Percent of shell diameter for disengagement 指定空间相对于壳体直径的百分比27(4)Impingement(壳体入口设置防冲板或导流板)27(a)壳程设置防冲板或导流板的条件27(b)Impingement protection type防冲挡板及导流板类型27(d)Impingement plate diameter防冲板直径28(e)Impingement plate length and width防冲挡板的长度和宽度29(f)Impingement plate thickness防冲挡板的厚度29(g)Impingement distance from shell ID壳体内侧到防冲挡板的距离29(h)Impingement clearance to tube edge防冲挡板到第一排换热管的距离29(i)Impingement plate perforation area %导流板穿孔面积百分数29(3) Layout Options布置29(a)Pass layout布置29(b)Design symmetrical tube layout对称布管选项30(c)Maximum % deviation in tubes per pass每程管子的最大偏差30(d)Number of tie rods拉杆数31(e)Number of sealing strip pairs密封条对数32(f)Minimum u-bend diameterU型管最小的直径32(g)Pass partition lane width隔板间距33(h)Location of center tube in 1st row第一排管中心位置34(i)Outer tube limit diameter布管限定圆直径(设计过程无用)34(4)Layout Limits布置的限定35(a)Open space between shell ID and outermost tube壳体内径与最外侧换热管的间距35(b)Distance from tube center换热管管中心与中心线之间的距离36(5) Clearances空隙尺寸36(a)Shell ID to baffle OD壳体内径与折流板外径的距离36(b)Baffle OD to outer tube limit折流板外径到最外侧换热管之间的距离36(c)Baffle tube hole to tube OD折流板管孔到换热管外径之间的距离366.4 Baffles折流板37(1)Baffle type折流板类型38(2)Baffle cut(% of diameter)折流板切割率40(3)Baffle cut orientation折流板切割方向406.5 Tube supports(支承板)41(1)Number of Intermediate Supports中间支承数(折流板中支承板数)416.6Rod Baffes折流杆446.7 Rating/Simulation Data446.8 Nozzles(接管)456.9 热虹吸换热587、Design Data设计数据587.1 design Constraints设计参数约束59(1)Shell/Bundle(壳程/约束)59(a)、Shell diameter壳体直径59(b)、Tube length换热管长59(c)、Tube passes管程数60(d)、Baffle折流板间距61(e)、Use shell ID or OD as reference以内径还是外径为参考(一般为默认)61(f)、Use pipe or plate for small shells指定小直径壳程使用无缝钢管还是有封钢板62(g)、Minimum shells in series最少的换热器个数62(h)、Minimum shells in parallel换热器壳程数62(i)、Allowable number of baffles折流板数限制(一般默认)62(j)、Allow baffles under nozzles管口下是否允许放置折流板63(k)、Use proportional baffle cut使用比例切割折流板(一般默认)63(2)Process过程64(a)、Allowable pressure drop允许的压力降64(b)管内流速657.2 材料87三、其它手动设计961、筒体厚度96第三章 换热器设计一、例子已知混合气体的流量为227801kg/h,压力为6.9Mpa,循环冷却水的压力为0.4Mpa,循环水入口温度29,出口温度39,试设计一台列管式换热器,完成该任务。混合气体在85下有如下物性:热容cp1=3.297kJ/kg,导热系数=0.0279w/m,粘度=0.000015Pas,密度=90kg/m3。循环冷却水在34下有如下物性:热容cp1=4.174kJ/kg,导热系数=0.624w/m,粘度=0.000742Pas,密度=994.3kg/m3。 二、Input输入模块1、problem definition问题定义模块1.1、description基本描写(1)标题(Heading)公司(company)地址(location)服务对象(Service of Unit)、本单位联系人(our Reference)项目编号(item No)、对方单位联系人(Your Reference)日期(date)等。 (2)物流名称热流(Hot side) 冷流(Cold side)(3)备注(Remarks)2、 application options(程序运行环境选择)2.1、Hot side application(热流运行环境)(1)Liquid,no phase change(液体,无相变化)(2)Gas,no phase change(气体,无相变化)(3)Narrow range condensation: Application covers the cases where the condensing side film coefficient does not change significantly over the temperature range. Therefore, the calculations can be based on an assumed linear condensation profile. This class is recommended for cases of isothermal condensation and cases of multiple condensableswithout noncondensables where the condensing range is less than 6C (10F).狭窄范围内的冷凝:用于冷凝液膜系数不随温度改变的情况。因此,该计算认为冷凝呈线性曲线。该方法推荐用于等温冷凝和在6C下不冷凝的多组分冷凝。(4)Multi-component condensation: Application covers the other cases of condensation wherethe condensing side film coefficient changes significantly over the condensing range.Therefore, the condensing range must be divided into several zones where the properties andconditions must be calculated for each zone. This class is recommended for all cases wherenoncondensables are present or where there are multiple condensables with a condensingrange of more than 6C (10F).多组分冷凝:用于冷凝液膜系数随温度改变的情况。因此,根据特性和环境,将冷凝温度范围分成几个区间,然后对每一个区间进行计算。该方法推荐用于不凝液和在高于6C下冷凝的多组分冷凝。Saturated steam condensation(饱和蒸气冷凝)Falling film liquid cooler(降膜液体冷却器)2.2、Condensation curve冷凝曲线You can input a vapor/liquid equilibrium curve or have the program calculate the curve using ideal gas laws or several other non-ideal methods.你可以输入一个汽/液平衡曲线或使用理想气体定律或其他一些非理想的计算方法计算曲线的程序2.3、Condenser type冷凝器类型Most condensers have the vapor and condensate flow in the same direction. However, forsome special applications where you want to minimize the amount of subcooling you canselect a knockback reflux condenser type. The condensate formed flows back towards thevapor inlet. With this type of condenser, you should consider using the differentialcondensation option if the program calculates the condensation curve.2.4、Cod side application(冷流运行环境)(1)Liquid,no phase change(液体,无相变化)(2)Gas,no phase change(气体,无相变化)(3)Narrow range vaporization: 狭窄范围内的蒸发(4)Multi-component vaporization多组分蒸发 2.5、Location of hot fluid流程安排(热流位置)Tube side(管程)、shell side(壳程),(1)较脏和易结垢的物流应走易于清洗的一侧。对于固定管板式、浮头式换热器,一般应使易结垢流体流经管程,而对于U型管换热器,易结垢流体应走壳程。如冷却水为易结垢流体。若必须走壳程,则应采用正方形管子排列,并采用可拆式换热器(浮头式、填料函式、U形管式)。(2)有时在设计上需要提高流体的流速,以提高其传热膜系数,在这种情况下,应将需要提高流速的流体放在管程。这是因为管程流通截面积一般较小,且易于采用多管程结构以提高流速,(3)具有腐蚀性的流体应走管程,这样可以节约耐腐蚀材料,降低换热器成本。(4)压力高的流体应走管程。这是因为管子直径小,承压能力强,能够避免采用耐压的壳体和密封措施。(5)具有饱和蒸汽冷凝的换热器,应使饱和蒸汽走壳程,便于排出冷凝器。(6)粘度大的流体应走壳程,因为壳体内的流体在折流板的作用下,流通截面和方向都不断变化,在较低的雷诺数下就可达湍流状态。(7)为了节省保温层和减少壳体厚度,高温物流一般走管程,有时为了物料的冷却,也可使高温物流走壳程。(8)若两流体温差较大,对于刚性结构的换热器,易将传热膜系数大的流体通入壳程,以减小温差应力。(9)流量小的液体一般走壳程,因为壳体内的流体在折流板的作用下,流通截面和方向都不断变化,在较低的雷诺数下就可达湍流状态。(10)对压力降有特定要求的工艺物流走管程,因管程的传热系数和压降计算误差小。(11)传热膜系数较小的物流(如气体)应走壳程,易于提高传热膜系数。(12)有毒性的流体走管程,以减少泄露机会。注意:采用Aspen进行计算是,可以采用试的方法,首先让其热流体走管程,计算传热系数及换热面积;然后再假设走壳程,计算传热系数及换热面积。最后取传热系数最大,换热面积最小的情况。 2.6、Program mode(程序模式选择:设计、优化、模拟) Design(设计)、Rating(优化)、Simulatin(模拟)、Selest from standard file(从标准文件中选择),3、process data物流参数输入3.1、Fluid name(流体名称)3.2、Fluid quantity, total(热或冷流体总流速)选择单位、依据条件输入冷、热流体流量,3.3、Temperature冷热流体进出口温度3.4、Operating Pressure(absolute) 绝对操作压力选择单位、依据条件输入冷、热流体进出口压力3.5、Heat exchanged交换热量若交换热量没有直接给出,不输。3.6、allowable pressure drop允许的压力降一般情况下,流体流过换热器的阻力或压力降为10000100000Pa,气体为100010000Pa。允许的压力降往往与换热器的操作压力有关、操作压力越大,允许流体阻力 可相应大一些。如操作压力为P200000Pa,P50000。3.7、fouling resistance污垢热阻4、热平衡计算环境This input allows you to specify whether you want the total flow rate or the outlet temperature to be adjusted to balance the heat load against the specified heat load or the heat load calculated from the opposite side. The program will calculate the required adjustment.There is also an option to not balance the heat loads, in which case the program will designthe exchanger with the specified flows and temperatures but with the highest of the specifiedor calculated heat loads.输入允许您指定是否总流量和出口温度,要调整到平衡的热负荷与指定的热负荷和热负荷从对面的计算。该程序将计算所需的调整。还有一个选择是不平衡的热负荷,在这种情况下,程序设计换热器与指定的流动和温度而指定的最高或计算热负荷。5、 Physical Property Data物理特性数据(1)Property Option(特性程序选择一般默认)(2) Hot Side Composition热物质组成(若未知可不输)(3)Hot Side Properties(热物流特性)(1)Temperature(温度),(2)Specific heat(热容)cp1=3.297kJ/kg(3)Thermal cond(导热系数)=0.0279w/m(4)Viscosity(粘度)=0.000015Pas(5)Density(密度)=90kg/m3(6)Molecular weight(分子量)(7)Diffusivity(扩散率)(4)cold side composition(冷物流组成与前热物流组成一样)(5) cold side properties(冷物流特性)(1)Temperature(温度),(2)Specific heat(热容)cp1=4.174kJ/kg(3)Thermal cond(导热系数)=0.624w/m(4)Viscosity(粘度)=0.000742Pas(5)Density(密度)=994.3kg/m3(6)Surface tension(表面张力)(7)Critical pressure(临界压力)(8)Latent heat(潜热)温度、热容、导热系数、粘度、密度、分子量、扩散率6、 Exchanger Geometry(结构参数)6.1 exchanger Type(换热器类型)(1)Front head type(换热器前端管箱)A-channel & B-bonnet bolted C-integral tubesheet bundleremovable cover or integral with tubesheet & removeable (平盖管箱) 封头管箱 ( 选择) 用于可拆管束与管板制成一体的管箱N-integral tubesheet & nonremovable bundle D-high pressure enclosure与管板制成一体的固定管板管箱 特殊高压管箱A full access cover provided in the A, C, (A,C提供了一个完整的检修盖) N type heads may be needed if the tube side of the exchanger must be cleaned frequently. (如果换热器的管程必须经常清洗时,则需N型)The B type is generally the most economical type head. (B型通常是最经济型的)Default: B Type(默认值:B型)(2)Shell type(壳体结构)E-one pass shell F-two pass shell with long baffle单壳程 (选择) 具有常隔板的双壳程 G-Split flow H-double split flow分流 双分流J-divided flow(nozzles:1 in,2 out) K-kettle无隔板分流(或冷凝器壳体) 釡式重沸器X-crossflow V-vapor belt交错流 蒸汽机J-divided flow(nozzles:2 in,1 out)无隔板分流(或冷凝器壳体)E type: Generally provides the best heat transfer but also the highest shell side pressure drop. Used for temperature cross applications where pure counter current flow is needed.F type: This two pass shell can enhance shell side heat transfer and also maintain counter current flow if needed for temperature cross applications. G type: Will enhance the shell side film coefficient for a given exchanger size. H type: A good choice for low shell side operating pressure applications. Pressure drop can be minimized. Used for shell side thermosiphons. J type: Used often for shell side condensers. With two inlet vapor nozzles on top and the single condensate nozzle on bottom, vibration problems can be avoided.K type: Used for kettle type shell side reboilers.X type: Good for low shell side pressure applications. Units is provided with support plates which provides pure cross flow through the bundle. Multiple inlet and outlet nozzles or flow distributors are recommended to assure full distribution of the flow along the bundle. V type shell: This type is not currently part of the TEMA standards. It is used for very low shell side pressure drops. It is especially well suited for vacuum condensers. The vapor belt is an enlarged shell over part of the bundle length. Default: E type (except K type shell side pool boilers)(3)Rear head type(后端结构)L-removable channel with flat cover M-bonnet与A相似的固定管板结构 与B相似的固定管板结构N-integral channel with flat cover P-outside packed floating heat与C相似的固定管板结构 填料函式浮头S-floating head with backing device T-pull through floating head钩圈式浮头(选择) 可抽式浮头U-U-tube bundle W-floating head with lantem ringU型管束 带套环填料函式浮头固定管板式、浮头式、U型管式、填料函式浮头式换热器(冷热流体进口温度29,出口温度39,该换热器用循环冷却水冷却,冬季操作时,其进口温度会降低,考虑到这一因素,估计该换热器的管壁温之差较大,因此初步确定为选用浮头式换热器)The rear head type affects the thermal design, because it determines the outer tube limits and therefore the number of tubes and the required number of tube passes. Default: U type for kettle shells, M type for all others(4)exchanger position(换热器水平还是垂直安装)Horizontal(水平)、Vertical(垂直)Default: vertical for tube side thermosiphon; horizontal for all others默认:热虹吸换热器垂直安装,其他都水平安装) (5)cover密封(盖子)面类型(工艺计算没必要提供)(6)Tubesheet type管板形式管板类型对热计算和投资预算来说起着一个非常重要的作用。为了避免管侧和壳侧流体漏液,则往往选择双管板。双管板在固定管板换热器中最常用,同样也可用于U形管式换热器和外包装的浮动式换热器。双管板缩短了壳侧流体流动的长度,因此,降低了有效面积。也影响壳体接管的位置与挡板间距。间隙式双管板有一个空间,通常约150毫米(6in)。整体式双管板是由加工出一个蜂巢图案内板单块厚使任何泄漏流体穿过管板的内漏,这种类型是罕见的,因为它需要特殊的制作工具和经验。默认值:单板The tubesheet type has a very significant effect on both the thermal design and the cost.Double tubesheets are used when it is extremely important to avoid any leakage between the shell and tube side fluids. Double tubesheets are most often used with fixed tubesheet exchangers, although they can also be used with U-tubes and outside packed floating heads.Double tubesheets shorten the length of the tube which is in contact with the shell side fluid and therefore reduce the effective surface area. They also affect the location of the shell sidenozzles and the possible baffle spacings.The gap type double tubesheet has a space, usually about 150 mm (6 in.), between the inner(shell side) and outer (tube side) tubesheets. The integral type double tubesheet is made bymachining out a honeycomb pattern inside a single thick piece of plate so that any leakingfluid can flow down through the inside of the tubesheet to a drain. This type is rare, since itrequires special fabrication tools and experience.Default: normal single tubesheet(s)(7)Tube to tubesheet joint管子与管板的连接(工艺不关键)6.2 Tubes(换热管)(1)Tube type(管子类型)(a)Plain光管(b)finned tube翅片管(c)默认值:光管当壳程膜传热系数远比管程膜传热系数小时,常使用外翅片管。然而在一些情况下不推荐使用翅片管。如在壳程流动的物流污垢热阻大,或粘度大,或其表面张力大而容易凝结在设备表面的。“Wolverine”和”高效翅片管”的尺寸标准已在程序中建立了。其翅片管的标准外径有12.7,15.9,19.1和25.4mm(0.5,0.625,0.75和1in)。其他标准的翅片外径有38,50,63,76和89 mm(1.5,2.0,2.5,3.0和3.5 in),程序默认:19.1mm(0.75in)如果你指定翅片管的类型,那么你必须指定所需的翅片密度(即,由系统确定每英寸(或每米)的翅片数)。翅片密度由管材确定,你必须确定所需的翅片密度是市售的。此标准管是由“Wolverine”制造的“高性能管”,已被植入系统。如果你选择了其中的一个,程序将自动计算翅片高度,翅片厚度和翅片管内外表面积比。如果你不选择一个标准的翅片密度,那么你必须提供其他的翅片数据,这将在后面输入。Externally finned tubes become advantageous when the shell side film coefficient is much less than the tube side film coefficient. However there are some applications where finned tubes are not recommended. They are not usually recommended for cases where there is high fouling on the shell side, or very viscous flow, or for condensation where there is a high liquid surface tension.The dimensional standards for Wolverines High Performance finned tubes, are built into the program. These standard finned tubes are available in tube diameters of 12.7, 15.9, 19.1, and 25.4 mm or 0.5, 0.625, 0.75, and 1.0 inch. Reference the appendix for available sizes.Default: plain tubes附录:Standard fin outside diametersin.: 1.5 2.0 2.5 3.0 3.5mm: 38 50 63 76 89Program Default: Tube Outside Diameter + 0.75 in or 19.05 mmIf you specify fin tubes as the tube type, then you must specify the desired fin density (i.e., the number of fins per inch or per meter depending on the system of measure). Since the possible fin densities are very dependent on the tube material, you should be sure that the desired fin density is commercially available.The dimensional standards for finned tubes made by Wolverine, and High Performance Tube are built into the program. If you choose one of these, the program will automatically supply the corresponding fin height, fin thickness, and ratio of tube outside to inside surface area. If you do not choose one of the standard fin densities, then you must also supply the other fin data, which follows in the input.(2)Tube outside diameter(管子外径)(3)Tube wall thickness(管子壁厚)(4)Tube wall roughness(管子粗糙度)(5)Tube wall Specification(管子壁厚计算指定)有平均average、最小Minimum选项Tube wall specificationIn many countries, the tube wall thickness is specified as either average or minimum. Averagemeans the average wall thickness will be at least the specified thickness; typically thethickness may vary up to 12%. With minimum wall, all parts of the tube must be at least thespecified thickness.In the U.S., most heat exchanger tubes are specified as average wall thickness. In othercountries, for example Germany, the standard requires minimum wall.This item has a small effect on tube side pressure drop and a moderate effect on heatexchanger cost.Default: average管壁厚度在许多国家,管壁厚度指定为平均值。平均方法的平均壁厚至少要指定的厚度;通常厚度高达12%可能会有所不同。以最小的管壁,所有部件必须至少指定的厚度。在美国,大多数换热器管指定为平均壁厚。在其他国家,例如德国,标准要求的最小壁。这项对管侧压降和热适度影响小的影响换热器的成本。默认值:平均(6)Tube pich管心距(7)Tube material管子材质(8)Tube pattem换热管的排列Triangular正三角形、Rotated triangular选转45度的正三角形、Square正方形、Rotated square旋转45度的正方形。一般来说,正三角形排列在相同的管板面积上可排列较多的管子,而且管外传热膜系数较大,有利于增强壳程物流的湍流,但正三角形排列时管外机械清洗较为困难,而且管外流体的流动阻力也较大。正方形排列在同样的管板面积上可配置的传热管最少,但管外易于进行机械清洗,所以当管子外壁需要机械清洗,常采用这种排列。为了弥补各自的缺点,产生了转过一定角度的正方形排布和留有清理通道的三角形排布两种形式。(9)翅片管相关数据(a)Fin density翅片密度标准的翅片密度根据材料而定:碳钢19不锈钢16,28铜19,26铜镍90 / 10,16,19,26铜镍70 / 30,19,26镍基合金201 19镍400合金(蒙乃尔)28镍600合金(Inconel)28镍合金800 28哈氏合金30钛30海军19,26铝黄铜合金687 19The standard fin densities for various materials are:Carbon Steel 19Stainless Steel 16, 28Copper 19, 26Copper-Nickel 90/10 16, 19, 26Copper-Nickel 70/30 19, 26Nickel Car
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