超聲波基礎 v1.0

1、01/04/2011Xingeng LiSlide 1超聲波物位計基礎01/04/2011ToF 基礎Xingeng LiSlide 2內容介紹n 測量原理n 超聲波物位計的型號及參數n 現場安裝注意事項n 應用舉例要求掌握的內容要求掌握的內容 超聲波物位計的測量原理 產品的型號，及相應的特點與區(qū)別 主要的應用場合 根據實際的工況進行選型01/04/2011ToF 基礎Xingeng LiSlide 3超聲波物位計01/04/2011ToF 基礎Xingeng LiSlide 4測量原理01/04/2011ToF 基礎Xingeng LiSlide 5超聲波基礎n 超聲波是頻率超出人耳聽覺的上

2、限（約20kHz）的聲波，是一種聽不到的聲波。n 在19世紀末，科學家就已經開始對超聲波進行研究了。n 早在1794年，意大利的生物學家 Lazzaro Spallanzani 就已經發(fā)現蝙蝠是利用一種聽不見的聲波來在黑暗中定位的。20Hz20kHz20MHz次聲波次聲波聲波聲波超超 聲聲 波波01/04/2011ToF 基礎Xingeng LiSlide 6超聲波基礎n 1914年，Canadian Reginald Fessenden 在美國發(fā)明了最早的聲納。n 1942年，奧地利醫(yī)生杜西克首次利用超聲波原理來進行腦部掃描。n 直到20世紀80年代，超聲波原理才開始在工業(yè)上用于對物位的測量

3、。01/04/2011ToF 基礎Xingeng LiSlide 7超聲波基礎 超聲波物位測量所利用的兩個主要性質：01/04/2011ToF 基礎Xingeng LiSlide 8超聲波的傳播n 超聲波的傳播依賴于介質的存在n 氣體、液體或固體n 不同介質中的傳播速度不同n 氣體 液體 固體n 超聲波在理想氣體中的傳播速度只受到溫度溫度的影響n 現實中，聲速也會受到氣壓的影響01/04/2011ToF 基礎Xingeng LiSlide 9超聲波的傳播能量的損耗n 超聲波傳播時會因介質產生損耗。距離越長，能量越小。n 空氣中存在粉塵顆粒、小液滴時，一部分能量被散射。n 超聲波具有一定的波束角

4、，傳播距離越遠，單位面積上的能量越小距離01/04/2011ToF 基礎Xingeng LiSlide 10超聲波的反射n 當超聲波遇到界面時會發(fā)生反射n 聲阻抗：n 聲阻抗主要與介質的密度有關n 聲波在密度不同的界面上發(fā)生反射n 兩種介質的密度差（ ）越大，反射越強vZ01/04/2011ToF 基礎Xingeng LiSlide 11超聲波的反射n 常見介質的密度n 當在空氣中傳播的超聲波遇到液體或固體的表面時，由于密度差別很大，聲波幾乎全部被反射回去介質（液體）密度（kg/m3）汽油700乙醚710石油760酒精790煤油800苯880植物油920水1000介質（固體）密度（kg/m3）

5、聚丙烯870聚乙烯900PET樹脂1400鋁2700煤7000鐵7800銅8900鉛11300空氣：空氣：1.23 kg/m301/04/2011ToF 基礎Xingeng LiSlide 12超聲波的產生和接收壓電效應n 最早由皮埃爾居里和雅克居里兄弟發(fā)現n 壓電效應：某些物質在受到壓力產生變形的時候，其表面上會產生積聚的電荷n 逆壓電效應：在壓電材料表面施加電壓，壓電材料會產生機械形變 表面沒有電荷表面與內部的電荷極性相同極性相同表面與內部的電荷極性相反極性相反01/04/2011ToF 基礎Xingeng LiSlide 14超聲波探頭結構壓電晶體壓電晶體基底傳感器外殼；將傳感器整體封裝

6、，無需密封將膜片振動與外界隔離聲抗耦合材料01/04/2011ToF 基礎Xingeng LiSlide 15超聲波探頭的盲區(qū)n 同一塊壓電晶體既負責超聲波的發(fā)射，也負責接收n 因此，在發(fā)射狀態(tài)與接收狀態(tài)之間，需要一段時間使得壓電晶體從振蕩狀態(tài)恢復到靜止狀態(tài)，然后才能開始接收反射的超聲波信號n 根據ToF的原理，這段時間代表了空間的一段距離，即盲區(qū)盲區(qū)n 在盲區(qū)內，超聲波物位計是不能進行測量的01/04/2011ToF 基礎Xingeng LiSlide 16傳感器探頭輸出/顯示模塊去往上位機電子模塊超聲波信號將測量值轉換為輸出信號超聲波物位計的組成信號強度/時間信息各種補償算法生成波形圖（包

7、絡線）各種分析算法，確定回波物位值計算線性化計算01/04/2011ToF 基礎Xingeng LiSlide 17儀表型號及參數01/04/2011ToF 基礎Xingeng LiSlide 18超聲波物位計的分類n 一體化變送器n 分體式變送器01/04/2011ToF 基礎Xingeng LiSlide 19型號FMU30 1.5”FMU30 2”FMU40FMU41FMU42FMU43FMU44最大量程 （液體）5m8m5m8m10m15m20m最大量程 （固體）2m3.5m2m3.5m5m7m10m盲區(qū)0.25m0.35m0.25m0.35m0.4m0.6m0.5m精度3mm (0.

8、2)2mm (0.2)4mm (0.2)最大耐溫+60C+80C最大耐壓3 bar2.5 bar輸出420mA HART, PROFIBUS PA, FF一體式超聲波物位計01/04/2011ToF 基礎Xingeng LiSlide 20型號FDU90FDU91FDU91FFDU92FDU93FDU95FDU96最大量程 （液體）3m10m10m20m25mN/AN/A最大量程 （固體）1.2m5m5m10m15m45m70m盲區(qū)0.07m0.3m0.3m0.4m0.6m0.7m1.6m精度2mm (0.17)最大耐溫+80C+105C+95C+150C最大耐壓4 bar3 bar1.5 b

9、ar3 bar防護等級IP68分體式超聲波物位計探頭01/04/2011ToF 基礎Xingeng LiSlide 21分體式超聲波物位計變送器型號FMU90FMU95探頭數量2個10個輸出420mA HART PROFIBUS DP RelayPROFIBUS DP01/04/2011ToF 基礎Xingeng LiSlide 22價格價格性能性能Prosonic Tn 兩線，連續(xù)測量或開關n 最大測量距離 7 mn 價格低廉Prosonic Mn 兩線或四線n 最大測量距離 15 mn 菜單引導式操作n 現場顯示可觀察回波曲線n 帶HART, PA , FF通訊協(xié)議n 免費提供ToF-To

10、ol調試軟件Prosonicn 四線n 分體式n 最大量程70米n 可最多配五路繼電器輸出n 雙通道n OCM preprogrammedn 專門針對水/污水行業(yè)所設 計的功能（明渠、隔柵）n 可選配HART, DP, RS 485 接口n 可用COMMUWIN IIE+H 超聲波物位儀表的特點超聲波物位儀表的特點-針對不同行業(yè)的清晰定位針對不同行業(yè)的清晰定位01/04/2011ToF 基礎Xingeng LiSlide 24應用01/04/2011ToF 基礎Xingeng LiSlide 25超聲波物位計的特點（相對于接觸式測量）n 非接觸式測量n 安裝簡單n 不受介質粘附的影響n 不怕罐

11、內的攪拌n 測量距離長01/04/2011ToF 基礎Xingeng LiSlide 26影響超聲波物位計測量的因素n 接收的信號強度n 聲速n 傳播時間的確定n 虛假信號01/04/2011ToF 基礎Xingeng LiSlide 27影響測量的因素信號強度n 超聲波的能量：粘附，冷凝n 實際測量距離：n 傳播中的衰減：粉塵，蒸汽n 介質表面情況：泡沫、顆粒大小波動表面，安息角01/04/2011ToF 基礎Xingeng LiSlide 28影響測量因素聲速n 理想氣體中的聲速只和氣體的溫度有關：n 空氣在壓強較低時近似為理想氣體，無需壓力補償MTRcideal01/04/2011ToF

12、 基礎Xingeng LiSlide 29影響測量的因素介質表面情況（傳播時間）n 介質表面情況n 平靜表面n 波動/攪拌n 泡沫n 固體顆粒n 安息角01/04/2011ToF 基礎Xingeng LiSlide 30影響測量因素虛假回波n 罐壁上的障礙物n 多重回波01/04/2011ToF 基礎Xingeng LiSlide 31安裝注意事項罐頂安裝位置n 盲區(qū)n 避開罐內的障礙物/進料口n 不能裝在罐頂的中心處n 不能距離罐壁太近n 理想安裝位置：距離罐壁1/6直徑01/04/2011Ultrasonic measurementMoeller AndreasSlide 32Level

13、measurement in fat/oil mixtureView insideempty tankFMU90Requirements n Fat/oil mixture for coating process in food industry n Tank with conical ceiling and agitatorn Height 6 m/19.7 ftn Diameter 3 m/9.8 ftn 220 rpmn Process temperature 60 C/140 Fn Ambient temperature 60 C/140 Fn Atmospheric pressure

14、SolutionProsonic S FMU90 field housing and FDU91 sensorApplicationsFDU9101/04/2011Ultrasonic measurementMoeller AndreasSlide 33Level measurement in yoghurt productionRequirements n Tank in the yoghurt productionwith fruit mix n CIP at +135 C/+275 Fn Pressure abs. 1.5 bar/22 psin Triclamp connectionS

15、olutionProsonic S with fully welded stainless steel sensor FDU91FEmpty tankEchoes from cone 2.55 m/ 8.4 ft1.25 m/4.1 ft 0.55 m1.8 ftApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 34Level measurement in industrial waste water tankRequirements n Waste water mixture out of sodium hydr

16、oxide, sulfuric acid, textile color and watern Horizontal tankn Length 5 m / 16.4 ftn Diameter 3.5 m / 11.5 ftn Process temperature 2070 C/ 68 158 Fn Ambient pressureSolutionProsonic S with top-hat rail housing and FDU91 sensorFDU91Applications01/04/2011Ultrasonic measurementMoeller AndreasSlide 35L

17、evel measurement in storm water basinRequirements n Level measurement in a storm water basinn Control and recognition of the overload amount to the sewage treatment plantSolutionn Prosonic S with FDU91 sensor and mounting anglen Flood-proof sensor according to IP68/NEMA6PApplications01/04/2011Ultras

18、onic measurementMoeller AndreasSlide 36Parshall flumeRequirements n 9“ Parshall flumen waste watern atmospheric pressuren relay for flow pulse outputSolutionProsonic S FMU90 transmitter with top-hat rail housing and FDU91 sensorApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 37Flow

19、measurement in open channelsRequirementsn Flow measurement in an open channelSolutionn Prosonic S with FDU91 sensorn Pre-programmed flow curves includedn Summation of the flow rate by integrated counterApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 38Screen control (1)Requirements

20、n Control of the screen by differential level outputsn Waste watern Atmospheric pressureSolutionProsonic S FMU90 transmitter and two sensors FDU91in front of screenbehind the screenApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 39Screen control (2)gridin front of screengridbehind t

21、he screenApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 40Screen control (3)Requirements n Screen control in a sewage treatment plantSolutionn Prosonic S with 2 FDU91 sensorsn Measurement of the different level in front of and behind the screenn Control of screen cleaning by relay

22、integrated in the deviceApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 41Level measurement in a pump sumpRequirements n Level measurement in a pump sump of an underground hydro-electric power plantn Narrow shaft with obstacles n Measuring range 5 m / 16.4 ftSolutionProsonic M/T in

23、a plastic sonic guide tube (DN100) clear, big signalsLevel echoApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 42Pump controlRequirements n Level measurement in a pump shaftn Control of pumpn Measurement unaffected by obstacles Solutionn Prosonic S with sensor FDU9x n Control of pum

24、ps (up to 6) by integrated relaysApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 43Level measurement in power plantRequirementn Level monitoring in the raw water production (screen control, level measurement)Solutionn Installation of Prosonic T/M in shaft below bottom gridApplicatio

25、ns01/04/2011Ultrasonic measurementMoeller AndreasSlide 44Level measurement in acid and alkaline tanks (1)Requirement n Level measurement in acid/alkaline tank of a desalination plant (power plant)Solutionn Prosonic T/M easy and fast commissioningApplications01/04/2011Ultrasonic measurementMoeller An

26、dreasSlide 45Level measurement in acid and alkaline tanks (2)Requirements n Level measurement in viscous pigment solutionn Measuring range 4 m / 13 ftn Tank with dished bottomn Agitator 10 - 30 rpmSolutionn Prosonic M FMU41n Fast and easy commissioning by menu guidanceApplications01/04/2011Ultrasoni

27、c measurementMoeller AndreasSlide 46Level measurement in a twin tankRequirements n Level measurement in liquidPolyoln Storage tankn Diameter approx. 2.4 m / 7.9 ftn Height approx. 3.5 m / 11.5 ft n Tank 1Installation in dome ceilingn Tank 2: Bypass installation (DN100)Solutionn Prosonic Mn Fast and

28、easy commissioning by menu guidanceApplicationsTank 1Tank 201/04/2011Ultrasonic measurementMoeller AndreasSlide 47Level measurement in a reservoirRequirement n Level measurement in a process water reservoirSolutionn Prosonic T/Mn Easy and fast commissioning with an attractive priceApplications01/04/

29、2011Ultrasonic measurementMoeller AndreasSlide 48Level measurement above a filterRequirement n Level measurement above a filterSolutionn Prosonic T/M with mounting anglen Easy and fast commissioning with an attractive priceApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 49Level meas

30、urement in an asphalt mixing plantRequirements n Steel silo with conical bottomn Height 8 m / 26.2 ftn Diameter 5.6 m / 18.7 ftn Different types of stones, asphalt granulates, grain size 5 to 10 mm (0.2 to 0.4”)SolutionProsonic S transmitter with field housing and FDU93 sensorField housingFDU93Appli

31、cations01/04/2011Ultrasonic measurementMoeller AndreasSlide 50Bunker monitoringRequirements n Bunker for stone processingn Height of bunker 6 m / 19.7 ftn Ambient temperaturen Atmospheric pressuren Stones, grain size from 50 to 80 mm (2” to 3.2”)SolutionProsonic S FMU90 and FDU93 sensorFDU93 FMU90Ap

32、plications01/04/2011Ultrasonic measurementMoeller AndreasSlide 51Crusher monitoringRequirements n Crushern Ambient temperaturen Atmospheric pressuren StonesSolutionNon-contact measurement by Prosonic S FDU93FMU90 Applications01/04/2011Ultrasonic measurementMoeller AndreasSlide 52Monitoring of crushe

33、r feedRequirements n Level monitoring at a crusher feedn Avoiding of overloadn Monitoring of minimum level to prevent demolitionsSolutionn Prosonic S with FDU92 sensorn Non-contact and robust level measurementApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 53Level measurement in a t

34、ank with aluminum chipsRequirements n Silo with conical bottomn 9.5 m/29.5 ft high, 3300 mm / 10.8 ftn Ambient temperaturen Atmospheric pressuren Aluminum chips with a large grain sizen During filling process very loudSolutionProsonic S with FDU93sensor installed on a nozzle (height: 200 mm / 7.9”).

35、 Located 600 mm (2 ft) of the wall and 1000 mm (3.2 ft) above the media. FDU93Applications01/04/2011Ultrasonic measurementMoeller AndreasSlide 54Level measurement in fly ashRequirements n Silo n Height 8 m / 26 ft n Diameter 5 m / 16.4 ftn Temperature up to +110 C/+230 Fn Atmospheric pressuren Fly a

36、sh in a waste incineration plant n Extreme aggressive and corrosive atmosphereSolutionn Prosonic S non-contact measurement n Robust sensor with self-cleaning effect110 CTemperature CDistance mApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 55Level measurement in a coarse ash silo (p

37、ower plant)ash conveyor beltRequirement n Burning coal produces ashes in the boiler. The ashes are used in road construction. Solutionn Measurement of silo content with Prosonic Sn Evacuation of the ashes by lorriesApplications01/04/2011Ultrasonic measurementMoeller AndreasSlide 56Level measurement

38、at rotary crushersRequirements n Level monitoring under rough conditions n Vibrationn DirtSolutionn Non-contact level measurement with Prosonic Sn Robust sensor design with self-cleaning effectn Switch points individually adjustable by integrated relaysApplications01/04/2011Ultrasonic measurementMoe

39、ller AndreasSlide 57Level measurement in silos or storage tanksRequirements n Level measurement in a storage tankn Product: PE powder n Silo height: 28 m /92 ftn Silo diameter: 3.5 m / 11.5 ftn Filling: 14 - 20 t / h (pneumatically)Solutionn Non-contact level measurement with Prosonic Sn Robust sensors with self-cle