泵原理與節(jié)能

ReducingFacilityEnergyCostsbyOptimizingPumpingSystems

通過(guò)優(yōu)化泵送系統(tǒng)降低設(shè)備的能源成本向文國(guó)

中國(guó)電機(jī)節(jié)能推廣專家組

教授

WorkshopTopics主要內(nèi)容IntroductiontoEnergyConservationBenefitsEnergyBasicsHowElectricUtilitiesBillforEnergyPumpSystemFundamentalsSystemRequirementsPumpsMotors,DrivesandControls節(jié)能介紹效益能源基礎(chǔ)電能費(fèi)用泵系統(tǒng)理論基礎(chǔ)

系統(tǒng)要求泵電動(dòng)機(jī)，驅(qū)動(dòng)及控制裝置WorkshopTopics主要內(nèi)容CollectingPumpSystemData泵系統(tǒng)數(shù)據(jù)的收集PumpSystemElevations 泵系統(tǒng)標(biāo)高NameplateInformation 銘牌信息FieldMeasurements 現(xiàn)場(chǎng)測(cè)量PumpSystemAnalysis泵系統(tǒng)分析CaseStudies 案例的研究分析IntroductiontoEnergyConservation

節(jié)能介紹financialandpollutionpreventionbenefitsofenergyconservation

節(jié)能的財(cái)務(wù)效益及環(huán)保效益

財(cái)務(wù)效益以某制藥廠為例：

一臺(tái)160kw

水泵，由于長(zhǎng)期工作在低效區(qū)，經(jīng)過(guò)高效改造，運(yùn)行效率得到提高，年運(yùn)行節(jié)約費(fèi)用可達(dá)37萬(wàn)元人民幣。情況比較普遍。環(huán)保效益SO2減排NOX減排CO2減排粉塵減排噪音等減排PumpSystemFundamentals

泵系統(tǒng)基本原理Thereareatremendousvarietyoffluidsystemswithequallyvariedpurposes

不同流體系統(tǒng)所泵送的流體可用于不同的使用場(chǎng)合Thepumpedfluidsupportsanotherproduct所泵送的流體被用作其它產(chǎn)品的介質(zhì)HeatremovaloradditionPowergeneration 散熱或供熱

發(fā)電Thepumpedfluidistheproduct所泵送的流體即是產(chǎn)品本身Oiltransport Potablewater 油輸送

飲用水Thinkofthesystemrequirements,orultimategoalofthesystem,asaconsumer

作為用戶，需要考慮系統(tǒng)的各種要求,或系統(tǒng)的最終目標(biāo)供電饋線變壓器電機(jī)斷路器/啟動(dòng)器無(wú)極變速傳動(dòng)裝置(電動(dòng))電機(jī)聯(lián)軸節(jié)泵系統(tǒng)流體最終目標(biāo)Theelectricutilityisthesourceforthesupplyofenergyusedbytheconsumer.Buttherearemiddle-menallalongthesupplychain.Somealmostalwaysgiveagooddeal,butotherscanbedeceptiveifyoudon'tkeepacloseeyeonthem.用戶所使用的能量供應(yīng)來(lái)自公用電力事業(yè)設(shè)施。但是供應(yīng)鏈上存在許多中間環(huán)節(jié)。其中一些環(huán)節(jié)非常有利，但是其它環(huán)節(jié)帶有欺騙性，必須予以密切關(guān)注。Animportantconsideration:

Systemrequirementsmayvarywithtime

非常重要的考慮：系統(tǒng)要求可能隨時(shí)間而變化Seasonalloads(chilledwater,associatedtowerwater,etc).季節(jié)性負(fù)載(冷卻水,相關(guān)水塔等).Processesthatareshutdownovernightorduringweekends在晚間或周末需要停車的工藝設(shè)備。Potableandwastewater生活飲用水及廢水。EXAMPLES例如Annualflowfluctuationexample

年流量波動(dòng)實(shí)例Averageflowrate平均流量Calendarmonth 月份123456789101112Wecansortthemonthsbyflowrate

我們可以通過(guò)流量變化對(duì)月份進(jìn)行分類排列876951043111221Averageflowrate平均流量Calendarmonth 月份Dailyflowfluctuationexample

日流量波動(dòng)實(shí)例Time 時(shí)間Flowrate流量12am6am12pm6pm12amThefluidsystem-itprovidesameansofdirectingandcontrollingflow,butataprice

流體系統(tǒng)——流量與壓力的關(guān)系Pressure 壓力"Systemcurve““系統(tǒng)特性曲線"Flowrate 流量Guesswhopaysthesystemprice--thepump

(butitjustpassesthecostalong….)

猜想由誰(shuí)支付系統(tǒng)價(jià)格——泵(但是只需要將成本傳遞到….)"Pumpcurve“"泵特性曲線"Flowrate 流量Pressure 壓力Thepumpandsystemonlytransactbusiness

onepointatatime

泵及系統(tǒng)只在某一時(shí)間的一交點(diǎn)處運(yùn)轉(zhuǎn)工作"Pumpcurve“"泵特性曲線""Systemcurve““系統(tǒng)特性曲線"OperatingPoint運(yùn)轉(zhuǎn)工作點(diǎn)Flowrate 流量Pressure 壓力Themotor,yetanothermiddleman,passesthecostalongtothepowersupply

電機(jī),還有其它中間環(huán)節(jié)，可以將成本傳遞到供電上Flowrate 流量Power 功率

Shaftpower軸功率Pumpfluidpower泵流體功率Electricpower電功率Motorefficienciesareessentiallyconstantovermuchofthemotorloadrange

電機(jī)效率在大部分電機(jī)負(fù)載范圍內(nèi)都是恒定不變的100959085807570Efficiency,%效率,%1009080706050403020100Load,%rated負(fù)載,%額定負(fù)荷100hp

100馬力10hp10馬力Theadjustablespeeddrive,whenpresent,canhaveanimpactonthenatureofseveralelements供電饋線變壓器電機(jī)斷路器/啟動(dòng)器無(wú)極變速傳動(dòng)裝置(電動(dòng))電機(jī)聯(lián)軸節(jié)泵流體系統(tǒng)最終目標(biāo)如果采用無(wú)極變速傳動(dòng),將對(duì)系統(tǒng)的許多構(gòu)成環(huán)節(jié)的性質(zhì)產(chǎn)生影響Combinedmotoranddriveefficiency:

Centrifugalloadsimulation

電機(jī)及驅(qū)動(dòng)裝置的聯(lián)合效率（模擬離心負(fù)載）8884807672Combinedefficiency,%聯(lián)合效率,%1009080706050Speed,%rated 速度,%額定速度Average平均效率Best 最佳效率Worst 最差效率Note:Used50-hp(38kW),2-pole,standardefficiencymotor注：采用50-馬力(38kW),2-極,標(biāo)準(zhǔn)效率的電機(jī)Fluidsandfluidsystemsarealotlikepeople…..

流體及流體系統(tǒng)更有與人相似之處…..Theydependonanexternalpowersourcetogetthemstartedandkeepthemmoving流體系統(tǒng)利用外部能源啟動(dòng)并使流體移動(dòng)。Theyarehappiestwhentherearefewtwists,turns,suddenstopsandstarts流體及流體系統(tǒng)內(nèi)部需要有非常少的曲折、回轉(zhuǎn)、突然停止和啟動(dòng)。Theyareaffectedbywherethey’vebeen,wheretheyare,andwherethey’regoing流體及流體系統(tǒng)受其過(guò)去、現(xiàn)在和將來(lái)所處地點(diǎn)影響。Theyneedsomeboundariestobeeffective,butiftheboundariesaretootight,therewillbefriction(doesanyonehaveateenager?)流體必須受到某種程度的約束限制，但是如果限制太嚴(yán)厲，將出現(xiàn)流體動(dòng)力摩擦(如同每個(gè)人處于十幾歲青少年階段的狀態(tài)，哪個(gè)人沒(méi)從該年齡段經(jīng)過(guò)呢?)。

Pumpingsystemoptimizationconcepts

泵抽送系統(tǒng)優(yōu)化概念Properlysizesystemstomeetcurrentneeds正確配置系統(tǒng)規(guī)模以滿足當(dāng)前要求。Avoidunnecessaryfrictionlosses防止不必要的流體動(dòng)力摩擦損失。Balanceoperationwithactualneeds按照實(shí)際需要平衡運(yùn)行。Itisimportanttoproperlymaintainsystems正確對(duì)系統(tǒng)進(jìn)行維修保養(yǎng)。Pumpingsystemoptimizationconcepts

泵抽送系統(tǒng)優(yōu)化概念Lookforopportunitiestoreducespeed尋找降低速度的可能性。Limitthrottledflowcontrolandbypassflow對(duì)系統(tǒng)內(nèi)節(jié)流控制和旁流進(jìn)行限制。Applyspeedcontroldevices,suchasvariablefrequencydrives(VFDs),withcaution采用速度控制裝置,諸如變頻驅(qū)動(dòng)(VFD)。Considermultiplepumpsforperiodicpeakdemands考慮采用多級(jí)泵配置以滿足周期性峰值的要求。-Prescreeningmotorsystems-

Findingtheeasierroadtogreatersavings

-預(yù)先篩查電機(jī)系統(tǒng)-

發(fā)現(xiàn)更能夠節(jié)約成本的更容易的途徑Primaryprescreening:

Thefirstpriorityistousecommonsense

主要篩查內(nèi)容：可以優(yōu)先采用經(jīng)驗(yàn)常識(shí)進(jìn)行篩查Turntheequipmentoffifitisn'tneeded如果不需要，關(guān)掉該設(shè)備。Focusonthelargeequipmentthatrunsalot重點(diǎn)關(guān)注經(jīng)常運(yùn)行的大型設(shè)備。Secondaryprescreening:...

輔助篩查內(nèi)容:...Therearetwodifferentmethodsthatcanbeusedinsecondaryprescreening:輔助篩查可以采用兩種不同的方法進(jìn)行:LookingatSymptoms查看征兆AnalysisoftheSystem對(duì)系統(tǒng)進(jìn)行分析and/or和/或SYMPTOMS:Looking&Listening

征兆診斷:看&聽(tīng)Somesymptomsofinterest:需要注意的一些征兆:Systemswiththrottledflowcontrolorbypassflowcontrol系統(tǒng)帶有節(jié)流控制或旁流控制。Thepresenceofsignificantcavitationnoise,eitheratthepumporelsewhereinthesystem在泵或系統(tǒng)的其它地方出現(xiàn)巨大的氣蝕噪音。Frequentpumpstartingandstopping

泵的頻繁啟停Multipleoperatingparallelpumps(wherethenumberofoperatingpumpsseldomchanges)多臺(tái)并行泵(在該地方運(yùn)行泵的數(shù)目很少發(fā)生變化)。Acquiringinformationandanalyzing

獲得所需要的信息資料并進(jìn)行分析Therealgoalbehindacquiringandanalyzingdataistoletusknowif:獲得并分析數(shù)據(jù)資料之后，我們的實(shí)際目標(biāo)是了解是否：wesetthebigtable,butnooneiscomingtodinner2) 我們準(zhǔn)備了大的餐桌，但是沒(méi)有人來(lái)此就餐。wearepouring20litersintoa10literbucket1) 我們正在將20升水倒入到10升桶中。OR或(Animbalancebetweenrequirementsandtheactualconditions)(在要求和實(shí)際條件之間存在不平衡)(Apumpthatisn'tproperlysizedfortheapplication)(規(guī)模上沒(méi)有正確滿足使用要求的泵)Observationsonsomeof

thepowertraincomponents

觀察了解一些能量鏈組成Utilitysystem-linelosses(wecannotdomuchaboutthat)Transformer-Veryefficient(typicallyupper90’s%)Breaker/starter-negligiblelossesAdjustablespeeddrive-Tobediscussed(briefly)Motor-Tobediscussed(briefly)Coupling-Theselossesshouldbeminor!Pump-TobediscussedSystem-TobediscussedUltimategoal-Tobediscussed供電系統(tǒng)–電力線路損失(不過(guò)多討論)變壓器–效率非常高(通常超過(guò)90%)斷路器/啟動(dòng)器–損失可忽略不計(jì)無(wú)極變速傳動(dòng)-待討論(簡(jiǎn)單討論)電機(jī)-待討論(簡(jiǎn)單討論)聯(lián)軸節(jié)–該部分損失應(yīng)當(dāng)是次要的!泵-待討論系統(tǒng)-待討論最終目標(biāo)-待討論Understandtheultimategoal

理解最終目標(biāo)Maximizetheoveralleffectiveness.使系統(tǒng)的總效率最大化.最終目標(biāo)流體系統(tǒng)泵聯(lián)軸節(jié)電機(jī)無(wú)極變速傳動(dòng)裝置(電動(dòng))電機(jī)斷路器/啟動(dòng)器變壓器供電饋線Tooptimizethefluidsystem,itisessentialtounderstandtheultimategoalofthesystem

為了優(yōu)化流體系統(tǒng),有必要理解系統(tǒng)的最終目標(biāo)Understandwhythesystemexists理解為什么該系統(tǒng)能夠存在。Haveclearlydefinedcriteriaforwhatisreallyneeded明確確定真正需要什么的標(biāo)準(zhǔn)。Understandwhat'snegotiableandwhat'snot理解什么需要探討，什么不需要。(Youcanonlypourjustsomuchwaterintoabucket)(您只需要在桶內(nèi)倒入恰好這么多的水就可以了)“Mycupisoverflowing”(Overcapacity)

“我的杯子溢出了”(生產(chǎn)能力過(guò)剩)Heatexchangers熱交換器BuildingLoads建筑負(fù)載CoolingTower冷卻塔Demin.Waterpump(s)Demin.水泵Towerwaterpump(s)冷卻塔水泵77F(25C)82F(28C)79F(26C)77F(25C)Understandthefluidsystem

理解流體系統(tǒng)泵聯(lián)軸節(jié)電機(jī)無(wú)極變速傳動(dòng)裝置(電動(dòng))電機(jī)斷路器/啟動(dòng)器Maximizetheoveralleffectiveness.使系統(tǒng)的總效率最大化.最終目標(biāo)變壓器供電饋線流體系統(tǒng)Thereareavarietyofprocessandcontroltypes

有各種各樣的工藝及控制類型Continuous連續(xù)型Batch批處理型Combination混合型Canbeeithersteadyorvariableflow可以選用穩(wěn)定流量或可變流量On/off 開(kāi)/關(guān)Valvethrottling 閥門節(jié)流Bypassing 旁通Variablespeeddrive 變速驅(qū)動(dòng)Combinations 混合型Processtypes:工藝類型:Controltypes:控制類型:Ideally,fluidmovementenergyrequirements

areproportionaltomassandhead

理想狀態(tài)下,流體移動(dòng)的能量要求與質(zhì)量和壓頭成比例能量要求=11770Nm,或2.81大卡

30升(30公斤)m(低于一個(gè)M&M)(=美國(guó)糖果)40mstatichead40米靜壓頭(lessthanoneM&M)(=Americancandy)Idealpowerdepends

onhowfastitismoved

理想狀態(tài)下所要求的功率取決于流體移動(dòng)的快慢Powerrequired= 65watts所要求的功率=65瓦30升(30公斤)40min180seconds在180秒內(nèi)壓頭達(dá)到40米Importantfundamentalrelationships

重要的基本關(guān)系式AND并且Reducetheruntime降低運(yùn)行時(shí)間Reducetheflowrate 降低流量Reducethehead 降低壓頭Reduceenergyuse,cost降低能源消耗,成本}Fluidpower(W)=Q(m3/s)xH(m)xρx9.8or流體功率(瓦)=Q(米3/秒)xH(米)xρx9.8

或Fluidpower(kW)=Q(m3/hr)xH(m)xρ

?367or流體功率(瓦)=Q(米3/小時(shí))xH(米)xρ

?367

或Fluidpower(kW)=Q(lit/s)xH(m)xρ

?102流體功率(瓦)=Q(升/秒)xH(米)xρ

?102Fluidenergy=Fluidpower?operatingtime流體能量=流體功率x

運(yùn)行操作時(shí)間(ρ=specificgravity)(ρ=比重kg/m3)Howcloseistheactualsituationtoidealconditions?

實(shí)際情況與理想條件接近程度如何？650litersperpersonperday每人每天消耗650升水Requiredsupplypressure=35m(343kPa)所需要的供水壓力=35米(343千帕)Assumptions:假設(shè):

Itlookslikeacityof200,000wouldrequireabout520kWofpotablewaterpumpcapacity那么200,000人口的城市需要大概520千瓦容量的飲用水泵。Whatpowerisrequiredtoprovidepotablewaterto200,000people?向200000人口提供飲用水需要多少動(dòng)力?However,usingonesmallcityasanexample,theactualpowerrequiredwasover2500kW但是，以某一小城市為例，實(shí)際電能消耗需求超過(guò)2500kWClearly,theactualsituationdoesnotwork

likeouridealizedexample!Whynot?

非常明顯，實(shí)際情況與理想狀態(tài)不同，為什么呢?Moreflow,headthanneeded比所需要的更大的流量和壓頭要求。Processingplantrequirements工藝處理裝置的具體要求。Pipeandpipecomponentfriction管道及管道部件的流體動(dòng)力摩擦。Pumpinefficiency泵的效率。Allsystemsarenotflateverywhere所有系統(tǒng)并不是到處都平滑無(wú)阻力。OK.....whicharemostimportant?好..…所有這些都是非常重要的?Totrytoanswerthis,itisusefultoreview

theenergyrelationshipsinfluids

為了解答該問(wèn)題，有必要對(duì)流體當(dāng)中的能量關(guān)系進(jìn)行討論。Oneofthesinglemostimportantfluid

energyrelationshipswasidentifiedinthe1700’s

其中一個(gè)最重要的流體與能量關(guān)系在18世紀(jì)被確定Bernoulli伯努利Euler

歐拉ComponentSymbol 參數(shù)符號(hào) Velocity(速度) VThecombinedenergy,orhead,associatedwiththefluidvelocity,pressure,andelevationalongafrictionlessstreamlineisconstant,eveniftheindividualcomponentsarenot.即使單獨(dú)部件不滿足該要求，無(wú)流體動(dòng)力摩擦流線型裝置的相關(guān)能量,或壓頭,以及流體速度,壓力,及標(biāo)高是恒定不變的。Pressure(壓力) PElevation(標(biāo)高) ZBernoulli'sprinciple:Totalenergyis

constantalongafrictionlessstreamline

伯努利原理:流體沿?zé)o動(dòng)摩擦流線型的總能量是恒定不變的=fluiddensity,kg/m3g=gravitationalacceleration,9.8m/sec2Note:Unitsareinmofhead=流體密度,千克/米3g=重力加速度,9.8米/秒2注：壓頭的單位是米。1++Z1

V12

P1

2g

g

()2++Z2

V22

P2

2gg

()=Example:Whatpumpdischargepressure

isneededtogetwatertothetankat(2)?

例如:需要什么樣的泵輸送壓力才能將水輸送到儲(chǔ)水池(2)當(dāng)中?

Station蓄水站 1 2Velocity(m/sec) 3 0速度(米/秒)Pressure(kPa) ? 0壓力(千帕)Elevation(m) 0 15標(biāo)高(米)2P1115mWecaneasilycalculatetheheadatTank2

我們可以輕易計(jì)算儲(chǔ)水池2的壓頭

Station蓄水站 1 2Velocity(m/sec) 3 0速度(米/秒)Pressure(N/m2) ? 0壓力(牛/米2)Elevation(m) 0 15標(biāo)高(米)Station2totalhead:蓄水站2總壓頭:01000?9.8+(0)2

2?9.815+=15

m2P11Sincetheheadsatourtwopointsmustbeequal,

wecancalculatethepressureatpoint1

由于在兩點(diǎn)的壓頭必須相等,所以我們能夠計(jì)算點(diǎn)1的壓力Station1totalhead:蓄水站1總壓頭:

(3)2

P1

2?

9.8

9800++0=0.45+

P1

9800P1

=(15-0.45)?9800=142,590N/m2=143kPaor1.43barP1

=(15-0.45)?9800=142,590牛/平方米=143千帕或1.43巴2P1QQ1Notice:eventhough3m/secisarelativelyhighvelocity,thevelocityhead(0.45m)isverysmall.注意：即使3米/秒是相對(duì)高的速度，但流量壓頭(0.45米)也非常之小。Amorepracticalapplication,forour

purposes,istheventuriflowmeter

對(duì)于我們而言，更具有實(shí)際應(yīng)用價(jià)值的是文丘里流量計(jì)V1,P1V2,P2V2isgreaterthanV1;thereforeP2islessthanP1V2

大于V1;因此P2

小于P1Nowforanextremelyimportantfeaturetounderstand:

Systemperformancecurves

至此需要理解的非常重要的特性是:

系統(tǒng)性能曲線Systemcurvesaremadeupoftwofundamental

components-thestaticheadandthefrictionalhead

系統(tǒng)特性曲線包括兩部分-靜壓頭及流體動(dòng)力摩擦損失壓頭302520151050Head,m壓頭,米10008006004002000Static/Fixed流體靜力/固定系統(tǒng)Friction流體動(dòng)力摩擦系統(tǒng)Total合計(jì)Flowrate,m3/hr流量,米3/小時(shí)Illustrationoftwosystemtypes

兩個(gè)系統(tǒng)類型的圖解說(shuō)明Mostlystatichead主要靜壓頭Allfrictionalhead只有流體動(dòng)力摩擦損失壓頭Somesystemexamples

系統(tǒng)實(shí)例Staticheaddominatedsystemsinclude:靜壓頭起決定性作用的系統(tǒng)包括:Coolingtowerpumpsystems冷卻塔泵送系統(tǒng)Influentpumpsystemsatwastetreatmentplants污水處理裝置的注水泵系統(tǒng)。Mostly/completelyfrictionalsystemsinclude:大部分/全部為流體動(dòng)力摩擦系統(tǒng)包括:Closedcyclecoolingwatersystems封閉式循環(huán)冷卻水系統(tǒng)Returnactivatedsludgepumpsystemsatwastetreatmentplants在污水處理裝置回收淤漿泵系統(tǒng)Firstletuslookatsystemsthat

haveonlystatichead(i.e.,nofriction)--

liketheexamplewherewepumpedwater

fromonetanktoanother

首先了解只具有靜壓頭(也就是說(shuō)無(wú)流體動(dòng)力摩擦)的系統(tǒng)——

類似于將水從一個(gè)儲(chǔ)水池泵送到另外一個(gè)儲(chǔ)水池的例子。Thestaticheadcomponentdoesnotchangewithflowrate--threestaticheadcurves

靜壓頭不隨流量變化——三條靜壓頭特性曲線302520151050Head,m壓頭,米10008006004002000Flowrate,m3/hr流量,米3/小時(shí)Sincehydraulicpowerisproportionaltoflowratetimes

head,theidealpowerrequiredincreaseslinearlywithflow

由于流體功率與流量和壓頭成比例，所以

所要求的理想功率水流量線性的增加。706050403020100Fluidpower,kW流體功率,千瓦1000800600400200015m20m25mFlowrate,m3/hr流量,米3/小時(shí)Butwhataboutreality?

但是實(shí)際情況怎么樣呢?Intherealworld,frictionexists(bothwithinthefluiditselfandbetweenthefluidandpipewalls).在自然界當(dāng)中,存在流體動(dòng)力摩擦(既存在流體本身內(nèi)部，也存在于流體與管道壁之間).SohowmuchdoesfrictioncausetherealworldtodeviatefromtherelationshipsoftheBernoulliprinciple?因此流體動(dòng)力摩擦使實(shí)際情況與伯努利原理關(guān)系偏離到何種程度？Itdepends.Sometimesalittle,sometimesalot.在實(shí)際系統(tǒng)當(dāng)中，流體動(dòng)力摩擦的影響有時(shí)非常小，有時(shí)非常大Wecanslightlymodifythe

Bernoulliequationtoaccountforfriction:

我們可以輕微修改伯努利方程式來(lái)計(jì)算流體動(dòng)力摩擦:12++Z1=

V12

P1

2gg()++Z2

V22

P2

2gg()Hydraulicenergyatpoint2isloweratpoint1becauseofthefrictionloss,sowebalancetheequationbyaddingithere由于流體動(dòng)力摩擦損失，在點(diǎn)2的流體動(dòng)力能量低于點(diǎn)1的流體動(dòng)力能量，因此我們?cè)谶@里增加該項(xiàng)來(lái)平衡此方程式。+hf

Whataresomesourcesof

frictioninpumpingsystems?

在泵抽送系統(tǒng)當(dāng)中什么是產(chǎn)生流體動(dòng)力摩擦的根源?Pipewalls 管道內(nèi)壁Valves 閥門Elbows 彎頭Tees 三通Reducers/expanders 變徑接頭Expansionjoints 膨脹節(jié)Tankinlets/outlets 容器進(jìn)口/出口(Inotherwords,almosteverythingthatthepumpedfluidpassesthrough,aswellasthefluiditself)(換句話說(shuō)，幾乎所泵送流體經(jīng)過(guò)的所有物體，以及流體本身都是產(chǎn)生流體動(dòng)力摩擦的根源)。First,wewilldiscussfriction

lossconsiderationsinpipingitself

討論管道系統(tǒng)本身所造

成的流體動(dòng)力摩擦損失Pipefrictionlossestimatesareusuallybased

onanequationreferredtoasDarcy-Weisbach

管道流體動(dòng)力摩擦損失的評(píng)估

通常根據(jù)達(dá)西-威斯巴克方程式確定Thisequationisveryusefulinunderstandingwhichparametersinfluencefrictionlossesinpiping:對(duì)于理解影響管道流體動(dòng)力摩擦損失的參數(shù)，下面的該方程式是非常有用的。

hf

= pressuredropduetofriction(ft) f = Darcyfrictionfactor L = pipelength(ft) d = pipediameter(ft) = velocityhead(ft)hf=f??LdV22gV22g

hf

= 由于流體動(dòng)力摩擦(英尺)產(chǎn)生的壓力降 f = 達(dá)西流體動(dòng)力摩擦系數(shù) L = 管道長(zhǎng)度(英尺) d = 管道直徑(英尺) = 流量壓頭(英尺)V22gThefrictionfactoriswhatcouldbecalleda

fudgefactorthataccountsforavarietyofeffects

流體動(dòng)力摩擦系數(shù)被稱為插入系數(shù)用來(lái)計(jì)算各種影響因素fhf=

??V22gLdThefrictionfactor,f,isaffectedby:theroughnessofthepiping,theviscosityofthefluidbeingpumped,thesizeofthepiping,andthevelocityofthefluidff流體動(dòng)力摩擦系數(shù)f受如下因素影響：管道的粗糙程度。

所泵送流體的粘度。管道的尺寸規(guī)格。以及流體的流動(dòng)速度。Nowwewilldiscusspipingcomponents

andtheireffectonfrictionallosses

管道部件及其對(duì)

流體動(dòng)力摩擦損失的影響Pipingcomponentfrictionlossesarealso

primarilydependentonexperimentaldata

管道部件的流體動(dòng)力摩擦損失也主要取決于實(shí)驗(yàn)數(shù)據(jù)Forpipecomponents,frictionlosseshavegenerallybeenestimatedbasedonthevelocityhead.對(duì)于管道部件,流體動(dòng)力摩擦損失通常根據(jù)流量壓頭進(jìn)行評(píng)估。hf=K?V22gK = Losscoefficient

損失系數(shù) = velocityhead

流量壓頭Kisafunctionofsize,andforvalves,thevalvetype,andvalve%open.K是尺寸的函數(shù),取決于閥門,閥門類型,及閥門開(kāi)度占全開(kāi)位置的百分比。V22gSometypicalKvaluesfor

miscellaneouspipecomponents:

用于各種管道部件的一些典型K值:Component ComponentK管道部件

管道部件K值90°elbow,standard90°標(biāo)準(zhǔn)彎頭 0.2-0.390°elbow,longradius90°長(zhǎng)徑彎頭 <0.1-0.3Square-edgedinlet(fromtank)方邊進(jìn)口(容器) 0.5Dischargeintotank容器出口 1Checkvalve止回閥 2Gatevalve(fullopen)閘閥(全開(kāi)) 0.03-0.2Globevalve(fullopen)球形閥(全開(kāi)) 3-8Butterflyvalve(fullopen)蝶閥(全開(kāi)) 0.5-2Ballvalve(fullopen)球閥(全開(kāi)) 0.04-0.1Systemperformancecurves

foranallfrictionalsystem

系統(tǒng)性能曲線

用于所有流體動(dòng)力摩擦系統(tǒng)Ashasbeendiscussed,frictionallossesare

proportionaltothesquareofthevelocity,orflowrate

如前面所討論的,流體動(dòng)力摩擦損失與流速或流量的平方成比例1086420Head,m壓頭,米10008006004002000Doublingtheflowratequadruplestheheadloss如果流量加倍，那么將產(chǎn)生四倍的壓頭損失Flowrate,m3/hr流量,米3/小時(shí)Thefrictionallossesnaturallydropaspipesizeisincreased

30mofnewpipe(nominalpipediametersinmm)

當(dāng)管道尺寸增加時(shí)，流體動(dòng)力摩擦損失自然降低1.00.20.0Headloss,m壓頭損失,米500040003000200010000Flowrate,m3/hr3004005006007509001m/s1.5m/s2m/s流量,米3/小時(shí)Frictionalpoweris~proportionaltotheflowcubed:

30mofnewpipe

流體動(dòng)力摩擦功率與流量的立方成比例43210FrictionalkW流體動(dòng)力摩擦功率千瓦5000400030002000100003004005006007509001m/s1.5m/s2m/sFlowrate,m3/hr流量,米3/小時(shí)Headlossin300-mmbutterflyvalvesasafunctionofflowrateandvalveposition

300毫米蝶閥的壓頭損失與流量和閥門位置的函數(shù)關(guān)系曲線3.02.52.01.51.00.50.0Headloss,m壓頭損失,米100959085807570Valveposition,%open閥門位置,%全開(kāi)位置800m3/hr100m3/hr400m3/hr1000m3/hrPowerlostduetofrictionin300-mmbutterfly

valvesasafunctionofflowrateandposition

300毫米蝶閥的流體動(dòng)力摩擦所造成的功率損失與流量和閥門位置之間的函數(shù)關(guān)系曲線86420FrictionalkW流體動(dòng)力摩擦功率千瓦100959085807570Valveposition,%open閥門位置,%全開(kāi)位置800m3/hr100m3/hr400m3/hr1000m3/hrHeadlossforthreetypesof300-mm

controlvalvesat500m3/hr

三種類型的300毫米控制閥門在流量為500米3/小時(shí)的壓頭損失4.03.02.01.00.0Headloss,m壓頭損失,米100959085807570Valveposition,%open閥門位置,%全開(kāi)位置Linearglobevalve線性球形閥Butterflyvalve蝶閥Ballvalve球閥"Passive"elements,suchascheckvalves,

canalsohavesignificantheadlosses

“被動(dòng)”部件,諸如止回閥門，也能夠造成重大的壓頭損失(For300-mmswingcheckvalve(losscoefficientof2assumed)(300-毫米回轉(zhuǎn)止回閥門(假設(shè)損失系數(shù)為2)0.0Headloss,m壓頭損失,米6005004003002001000Flowrate,m3/hr流量,米3/小時(shí)Actualsystemsrangefromallfrictional

tosystemsthataredominatedbystatichead

靜壓頭起決定作用的所有流體動(dòng)力摩擦實(shí)際系統(tǒng)的范圍Wewillestablishthreeexamplesystemcurvestobeusedthroughouttherestofthispresentation:我們將建立三種實(shí)例系統(tǒng)特性曲線，貫穿使用于本演示的其余部分：Allfrictionalheadsystem只有流體動(dòng)力摩擦損失壓頭系統(tǒng)Systemwithamixtureofstaticandfrictionalhead系統(tǒng)帶有流體靜力和流體動(dòng)力摩擦損失壓頭Systemwithpurestatichead系統(tǒng)只帶有靜壓頭(Note:thecolorschemeusedforthethreesystemtypeswillbeusedthroughout)(注：三種系統(tǒng)類型所采用的顏色將在整個(gè)內(nèi)容貫穿使用)(Theworkingfluidwillbeambienttemperaturewater)(工作流體是環(huán)境溫度下的水)Systemheadcurvesforallfrictional,

allstatic,andcombinedstaticandfrictionsystems

所有流體動(dòng)力摩擦,流體靜力和綜合流體靜力和流體動(dòng)力摩擦系統(tǒng)的系統(tǒng)壓頭特性曲線50403020100Head,m壓頭,米10008006004002000Staticandfriction流體靜力和

流體動(dòng)力摩擦系統(tǒng)Frictiononly僅限于流體動(dòng)力摩擦系統(tǒng)Staticonly僅限于流體靜力系統(tǒng)Flowrate,m3/hr流量,米3/小時(shí)Theidealinputhydraulicpowerisproportional

totheproductofthesystemheadandcapacity

理想輸入流體功率與系統(tǒng)壓頭和容量成比例100806040200Fluidpower,kW流體功率,千瓦10008006004002000Staticandfriction流體靜力和

流體動(dòng)力摩擦系統(tǒng)Frictiononly僅限于流體動(dòng)力摩擦系統(tǒng)Staticonly僅限于流體靜力系統(tǒng)Flowrate,m3/hr流量,米3/小時(shí)Workingourwayfromthewatertothewallet

排除困難，尋求節(jié)約水泵送能量的有效方法Andfinally,thecostofrunningthemotor=Motorinputpower·operatinghours·perunitelectricitycost最終，電機(jī)運(yùn)行成本=電機(jī)輸入功率

x

運(yùn)行小時(shí)x每套裝置的電力成本MotorPump電機(jī)輸出功率

電機(jī)效率電機(jī)輸入功率(kwe)=流體功率泵效率泵輸入功率(千瓦)=(或電機(jī)輸出)米3/小時(shí)x米x

比重367流體動(dòng)力(千瓦)=Combiningalltherelationshipsforwater….

結(jié)合所有各個(gè)方面的關(guān)系….Ifweputthatalltogether,thecostofpumping=m3/hr·m·hoursofoperation·cents/kwhr367·pumpefficiency·motorefficiencyAkilowattinthewaterisworth1.3to2kilowattsonthewire!!!每千瓦水相當(dāng)于1.3到2千瓦電網(wǎng)線路的電力。IMPORTANT:重點(diǎn):如果我們將各種關(guān)系放在一起：水的泵送成本=米3/小時(shí)x

米x

操作運(yùn)行小時(shí)數(shù)x

美分/千瓦時(shí)367x

泵效率x

電機(jī)效率Sowithsomeassumptions,wecanconvert

flowrateandheadintoRMB:

因此從某種意義上說(shuō)，我們能夠?qū)⒘髁考皦侯^轉(zhuǎn)換成人民幣:0.83RMB/kwhrcombinedpump&motorefficiency=70%8760hours/yearoperation(100%)0.83元人民幣/千瓦時(shí)泵&電動(dòng)機(jī)聯(lián)合效率=70%8760小時(shí)/年運(yùn)行(100%)Justlikepower,thecostincreaseslinearlywithflowrateforpurelystaticheadsystems

對(duì)于單純靜壓頭系統(tǒng)，正如同功率一樣，成本隨同流量線性增加Combinedpump&motorefficiency=70%泵&電機(jī)的聯(lián)合效率=70%8306644983321660Annualcost,RMB1,000’s年成本,RMB1,000’s1000800600400200015m20m25mFlowrate,m3/hr流量,米3/小時(shí)4150033200249001660083000Annualfrictionalcost,RMB年流體動(dòng)力摩擦損失成本,RMB500040003000200010000Annualfrictionalcostsof30metersofclean,newpipe

@0.83RMB/kWh,70%combinedmotor&pumpefficiency

30米干凈，全新管道的年流體動(dòng)力摩擦損失成本

@0.83元人民幣/kWh,電機(jī)&泵聯(lián)合效率的70%3004005006007509001m/s1.5m/s2m/sFlowrate,m3/hr流量,米3/小時(shí)Frictionalcostcomparison:300-mmpipeandvalves

流體動(dòng)力摩擦損失成本對(duì)比:300-毫米管道及閥門0.83RMB/kwh,combinedpump&motorefficiency=70%0.83RMB/千瓦小時(shí),泵&電機(jī)聯(lián)合效率=70%830066404980332016600Annualcost,RMB年成本,RMB6005004003002001000Checkvalve(k=2.0)25mpipe(300-mm)ButterflyValve蝶閥止回閥(k=2.0)25米管道(300-毫米)Flowrate,m3/hr流量,米3/小時(shí)Annualcostforthethreesystemscase

三種系統(tǒng)的年成本0.83RMB/kwh,combinedpump&motorefficiency=70%0.83RMB

/千瓦小時(shí),泵&電機(jī)聯(lián)合效率=70%9968306644983321660Annualcost,(RMB1,000’s)年成本,(RMB1,000’s)10008006004002000Flowrate,m3/hrStaticandfriction流體靜力及流體動(dòng)力摩擦系統(tǒng)Frictiononly僅限于流體動(dòng)力摩擦系統(tǒng)Staticonly僅限于流體靜力系統(tǒng)流量,米3/小時(shí)Backtothethreebasicprinciplesto

minimizingfluidsystemenergyrequirements

三種基本原理使流體系統(tǒng)的能量要求最小TReducetheruntimeReducetheflowrateReducetheheadReduceenergyuse,costButhowdowedothat?但是我們?cè)鯓硬拍軌蜃龅侥?}降低運(yùn)行時(shí)間降低流量降低壓頭降低能量消耗,成本}THowdowereduceruntime,head&flowrate?

我們?nèi)绾谓档瓦\(yùn)行時(shí)間,壓頭&流量?avoidexcessivevalveandotherfrictionlosses防止過(guò)多的閥門及其它流體動(dòng)力摩擦損失keeppipingsystemflushedandclean保持對(duì)管道系統(tǒng)的沖洗并保持清潔keepflowratessteady-minimizinghighflowrateswings保持流量的穩(wěn)定-最大限度的降低高流量波動(dòng)meetthesystemneedsandnomore恰當(dāng)滿足系統(tǒng)的要求Cleaningoutthepipe….Piggingdevicesareavailablecommerciallyforpipecleaning

清潔管道….可以利用清管球裝置對(duì)管道進(jìn)行商業(yè)化清洗Source: /PictureGallary.htm來(lái)源: /P000305.jpgSomemorepigginginformation….

更多有關(guān)清管信息….Sources: /services.htm來(lái)源: /images/pigsmain.jpgUnderstandingthepump

對(duì)泵的了解Maximizetheoveralleffectiveness使系統(tǒng)的總效率最大化供電饋線變壓器電機(jī)斷路器/啟動(dòng)器無(wú)極變速傳動(dòng)裝置(電動(dòng))電機(jī)聯(lián)軸節(jié)泵流體系統(tǒng)最終目標(biāo)Pumpscanbegenerallyclassified

intothefollowingcategories

通常情況下，泵能夠被分為如下類型PumpTypes泵類型DynamicPumps動(dòng)力泵DisplacementPumps活塞泵EndSuctionCentrifugal 單側(cè)吸入離心泵SplitCase 分體泵VerticalTurbine 立式渦輪泵SpecialPumps 特種泵?JetPumps 噴射泵?Regenerativeturbines 再生渦輪泵?VortexPumps 渦流泵Reciprocating 往復(fù)式Rotary 旋轉(zhuǎn)式?Piston 活塞泵?Diaphragm 隔膜泵?ProgressiveCavity 螺桿泵?MultipleGear-Lobe 多齒葉泵?Peristaltic 蠕動(dòng)泵DifferencebetweenDynamic

andDisplacementPumps

動(dòng)力泵與活塞泵之間的差異DynamicPumps(typicallycalledcentrifugalpumps)arepumpsthatrequireenergytobeaddedcontinuously動(dòng)力泵(通常被稱作離心泵)是一種需要連續(xù)添加能量的泵。DisplacementPumpsarepumpswhereenergyisaddedperiodicallytoasetvolumeofwater活塞泵是一種需要周期性添加能量到設(shè)定的水容量的泵。OurFocusWillBeonDynamicorCentrifugalPumps

我們將關(guān)注動(dòng)力泵或離心泵Withinthecentrifugalpumpcategory,there

aremultiplesubcategories

各種離心泵還可以細(xì)分為多種多樣的子類Impellergeometry(i.e.,radial,mixed,axialflow)葉輪幾何結(jié)構(gòu)(例如徑流式，混合式，軸流式)Impellersidewall(open,semi-open,closed)葉輪側(cè)壁(全開(kāi)，半開(kāi)，關(guān)閉)Suction(singleordouble)吸入類型(單吸或雙吸)Stages(singleormultiple)分級(jí)(單級(jí)或多級(jí))Collector(voluteordiffuser)收集器(渦殼或擴(kuò)散體型)Orientation(verticalorhorizontal)方位(立式或臥式)etc.,etc.等等Thegeneralimpellergeometrysuggeststhegeneralheadandflowrelationship(andvice-versa)

一般情況下，葉輪的幾何尺寸能夠表示總壓頭與流量的關(guān)系(反之亦然)Radialflow徑向流動(dòng)Axialflow軸向流動(dòng)FrancisvaneormixedflowFrancis葉片或混合流動(dòng)方向Typicalpumpnameplateinformation

典型泵銘牌信息資料Flowrate(m3/hr)流量(米3/小時(shí))Head(m)壓頭(米)Rotatingspeed(rpm)轉(zhuǎn)速(轉(zhuǎn)數(shù)/分)Power(shaftkW)功率(軸功率，千瓦)Nameplatedataappliesto

oneparticularoperatingpoint

銘牌數(shù)據(jù)適用于一特定的運(yùn)行工作點(diǎn)50403020100Head,m壓頭,米10008006004002000Flowrate,m3/hrRated:715m3/hr,30m額定值：715米3/小時(shí),30米Head-capacitycurve壓頭-流量能力特性曲線流量,米3/小時(shí)Anothercharacteristiccurveofinterestisthe

shaftpowerasafunctionofflowrate

其它典型特性曲線是當(dāng)軸功率作為流量的一個(gè)函數(shù)的情況50403020100Head,m壓頭,米10008006004002000100806040200Shaftpower,kW軸功率,千瓦Headcurve壓頭特性曲線Shaftpowercurve軸功率特性曲線Flowrate,m3/hr流量,米3/小時(shí)Pumpcurveshapesvary:

Headcurvesfortwopumpdesigns

泵特性曲線形狀變化：兩臺(tái)泵的壓頭特性曲線50403020100Head,m壓頭,米10008006004002000Pump2泵2Pump1泵1Flowrate,m3/hr流量,米3/小時(shí)Shaftpowercurvesforthetwopumps

兩臺(tái)泵的軸功率特性曲線100806040200Shaftpower,kW軸功率,千瓦10008006004002000Pump1泵1Pump2泵2Flowrate,m3/hr流量,米3/小時(shí)Andfinally,efficiencycurvesforthetwopumps

最終,得到兩臺(tái)泵的效率特性曲線100806040200Efficiency,%效率,%10008006004002000Pump2泵2Pump1泵1Flowrate,m3/hr流量,米3/小時(shí)Nowwewillconnectapumptoasystem

現(xiàn)在我們可以將泵連接到系統(tǒng)當(dāng)中Theintersectionbetweenthepumpandsystemheadcapacitycurvesdefinestheoperatingpoint

泵與系統(tǒng)壓頭能力特性曲線之間的交點(diǎn)確定了運(yùn)行工作點(diǎn)5040302010