WO2022105081A1 - 一种燃气能量计量流量计 - Google Patents

一种燃气能量计量流量计 Download PDF

Info

Publication number
WO2022105081A1
WO2022105081A1 PCT/CN2021/083835 CN2021083835W WO2022105081A1 WO 2022105081 A1 WO2022105081 A1 WO 2022105081A1 CN 2021083835 W CN2021083835 W CN 2021083835W WO 2022105081 A1 WO2022105081 A1 WO 2022105081A1
Authority
WO
WIPO (PCT)
Prior art keywords
natural gas
unit
calorific value
gas
volume flow
Prior art date
Application number
PCT/CN2021/083835
Other languages
English (en)
French (fr)
Inventor
李诗华
任海军
徐荣华
王文军
刘金勇
Original Assignee
上海真兰仪表科技股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 上海真兰仪表科技股份有限公司 filed Critical 上海真兰仪表科技股份有限公司
Publication of WO2022105081A1 publication Critical patent/WO2022105081A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
    • G01K17/00—Measuring quantity of heat
    • G01K17/06—Measuring quantity of heat conveyed by flowing media, e.g. in heating systems e.g. the quantity of heat in a transporting medium, delivered to or consumed in an expenditure device
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N25/00—Investigating or analyzing materials by the use of thermal means
    • G01N25/18—Investigating or analyzing materials by the use of thermal means by investigating thermal conductivity
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N25/00—Investigating or analyzing materials by the use of thermal means
    • G01N25/20—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity

Definitions

  • the invention relates to a flowmeter for measuring natural gas energy, belonging to a flowmeter.
  • the volume energy of the former can reach 8,500 kcal, while the latter is 7,900 kcal, and the difference in volume energy is 600 kcal. There are big differences.
  • energy measurement can fully reflect the true value of natural gas as a fuel, and can provide users with more stable products and services.
  • energy metering is also an effective means to reduce the gap between natural gas supply and sales.
  • the difference between the intake and sales volume is also rising, which not only damages the interests of consumers, but also causes natural gas companies to suffer losses.
  • Energy metering can realize scientific, fair and accurate measurement of natural gas, which is the key to reducing the gap between natural gas co-selling.
  • the purpose of the present invention is to provide an instrument device capable of realizing natural gas energy measurement.
  • the technical solution of the present invention is to provide a gas energy metering flowmeter, which is characterized in that it includes:
  • a volume flow measuring unit used to measure the volume flow Q n of the natural gas
  • the calorific value detection unit is used to detect the unit calorific value H of natural gas, including an optical sensing module, a sound velocity sensing module and a calculation module, wherein:
  • the calculation module calculates the unit calorific value H of natural gas through the following formula (1):
  • the volume flow measurement unit includes a volume flow measurement module and a correction module, wherein:
  • the volume flow measurement module is used to measure the uncorrected volume flow Q g ;
  • the correction module corrects the volume flow Qg based on the following formula (2) to obtain the volume flow Qn:
  • P g represents the absolute pressure of natural gas measured by the correction module
  • P n represents the standard atmospheric pressure
  • T n represents the absolute temperature of natural gas in the standard state
  • T g represents the absolute temperature of natural gas measured by the correction module
  • Z n represents the compressibility of the medium in the standard state of natural gas
  • Z g represents the compressibility of the medium in the working state of natural gas.
  • the computing unit is integrated in the correction module.
  • the calorific value detection unit sends the obtained calorific value H per unit of natural gas to the correction module through a data line, and the correction module outputs the energy E.
  • the natural gas enters the gas filter unit through the air intake unit, the impurities in the natural gas are filtered out by the gas filter unit, and the filtered natural gas is decompressed to the target through the decompression unit
  • the pressure value is then sent to the calorific value detection unit and the volume flow measurement module.
  • the calculation method for calculating the energy E adopted by the flowmeter provided by the present invention is relatively simple, so that the fast and accurate measurement of the natural gas energy E can be realized.
  • Fig. 1 is the schematic diagram of the gas energy metering flowmeter disclosed in the embodiment
  • FIG. 2 is a schematic diagram of the internal structure of the gas energy metering flowmeter disclosed in the embodiment
  • Fig. 3 is the schematic diagram of the calorimeter in the embodiment, among the figure:
  • a gas energy metering flowmeter disclosed in this embodiment includes a volume corrector 1 (EVC intelligent volume corrector is used in this embodiment), a flowmeter 2, an intake joint 3, and an intake valve 4. Filter 5, pressure reducing valve 6, calorific value meter 7, one-way valve 8 and RS485 communication cable 9.
  • the intake joint 3 is connected with the casing of the flow meter 2. After the natural gas enters the flow meter 2, it also enters the filter 5 through the intake joints 3 and 4 intake valves. After the gas impurities in the natural gas are filtered out by the filter 5, the filtered natural gas is decompressed to 2-10KPa by the pressure reducing valve 6 and then enters the calorific value meter 7, and the calorific value meter 7 measures to obtain the unit calorific value H (unit) of the natural gas. is MJ/Nm 3 ). The calorific value meter 7 performs data communication through the modbus protocol (including RS485 and RS232), and transmits the unit calorific value H of the natural gas to the volume corrector 1 . The volume corrector 1 also calculates the energy E (unit is MJ) of the natural gas according to the volume flow Q g output by the flow meter 2, and displays the calculated result on the liquid crystal screen.
  • modbus protocol including RS485 and RS232
  • the energy E of natural gas is the product of the volume flow of natural gas and the unit calorific value. That is, the energy of natural gas depends on two factors: the volume flow of natural gas and the specific calorific value.
  • the energy flow measurement of natural gas is completed by two unrelated measurements, namely the measurement of volume or mass flow and the measurement of volume or mass calorific value. These two measurements are synthesized to calculate the energy of natural gas, as shown in the following formula (1) shown:
  • Q n is the volume flow or mass flow of natural gas in standard state, and the unit is Nm 3 or kg.
  • the volume flow Q n of the natural gas is measured by a gas waist wheel flowmeter, a gas turbine flowmeter or a gas ultrasonic flowmeter. This embodiment is described with a gas waist wheel flowmeter.
  • a differential pressure is generated at the inlet and outlet of the instrument, which acts on the waist wheel connected by a high-precision, synchronous gear, generating a torque.
  • This torque acts on a pair of waist wheels in turn, causing them to rotate.
  • the metering chamber thus formed between the housing and the belt wheel is periodically filled and emptied.
  • the number of revolutions of the waist wheel is proportional to the volume of gas passing through the meter.
  • the number of revolutions of the rotor is converted into a pulse signal by a magnetoelectric conversion device.
  • a corrector 1 is configured on the basis of precision manufacturing of a mechanical watch.
  • the corrector 1 is composed of a temperature and pressure detection channel and a processing unit, and is equipped with input and output interfaces.
  • the processing unit in the corrector 1 performs volume conversion according to the gaseous equation, and automatically corrects the compression factor.
  • the gaseous equation is shown in the following formula (2):
  • P g represents the absolute pressure of natural gas measured by the correction module, and the unit is kPa;
  • P n represents standard atmospheric pressure, 101.325kPa
  • T n represents the absolute temperature of natural gas in the standard state, 293.15K (20°C);
  • T g represents the absolute temperature of natural gas measured by the correction module
  • Z n represents the medium compressibility coefficient under the standard state of natural gas
  • Z g represents the medium compressibility coefficient under the working state of natural gas.
  • FZ is the overcompression factor, which is calculated according to the formula in the standard SY/ T6143-1996 of China National Petroleum Corporation.
  • the calorific value meter 7 in this embodiment adopts a combined calculation method of optical calorific value detection + thermal conduction calorific value detection.
  • the interference of impurity components on optical calorific value detection and the interference of impurity components on thermal conduction calorific value detection have an approximate constant a, as follows:
  • the optical calorific value HO obtained by the optical calorific value detection, HO HT- X, in the formula , HT represents the theoretical calorific value, and X represents the optical impurity interference.
  • H hc HT -Y
  • H T represents the theoretical heat value
  • Y represents the interference of heat conduction impurities
  • Y aX.
  • the volume corrector 1 uses the above formulas (1), (2) and (3) to calculate the energy E of the natural gas, and displays it on the liquid crystal screen.

Abstract

一种燃气能量计量流量计，包括体积流量测量单元，用于测量得到天然气的体积流量Qn；热值检测单元，包括光学传感模块、声速传感模及计算模块，用于检测天然气单位发热量H；计算单元，用于计算得到天然气的能量E，E＝Qn×H。可以实现对天然气能量E快速、准确的计量。

Description

一种燃气能量计量流量计 技术领域
本发明涉及一种测量天然气能量的流量计，属于流量计。
背景技术
随着我国天然气消费规模持续增长，天然气对外依存度不断攀升，以及天然气管网设施独立开放后天然气来源趋于多元化，因计量单位不统一，不同来源的天然气混输于同一管网产生的矛盾纠纷日渐凸显。
在众多贸易计量的方式中，能量计量是目前国际上最流行的天然气贸易结算方式。国际上大多数国家均采用能量计量方式结算，并制定了天然气能量计量的相关法令法规、能源政策和价格政策。而我国天然气以体积计量为主，但随着国内经济发展，天然气对外依存度逐渐提升，天然气管网涉及气源种类愈发繁多，且不同类型的天然气组分各不相同，单位体积发能量相差较大。因此，我国天然气计量方式由体积计量向能量计量转变迫在眉睫。与此同时，体积计量方式也并不利于我国在天然气国际贸易中与国际惯例接轨。
以西气东输陕京一线和陕京二线为例，前者体积发能量可达8500千卡，而后者为7900千卡，体积发能量相差600千卡，使用体积计量方式易导致用户使用燃气的质量存在较大差异。
相对于体积计量，能量计量更能充分体现天然气作为燃料的真正价值，可为用户提供更为稳定的产品和服务。不仅如此，采用能量计量也是降低天然气供销差率的有效手段。伴随着我国用气量的不断增加，进气量与销气量之差也不断上升，这不仅损害了广大消费者的利益，也会使天然气公司遭受损失。而能量计量能够实现对天然气科学、公平的精准计量，是降低天然气共销差率的关键。
发明内容
本发明目的是：提供一种能够实现天然气能量计量的仪表设备。
为了达到上述目的，本发明的技术方案是提供了一种燃气能量计量流量计，其特征在于，包括：
体积流量测量单元，用于测量得到天然气的体积流量Q n；
热值检测单元，用于检测天然气单位发热量H，包括光学传感模块、声速传感模及计算模块，其中：
光学传感模块用于检测得到天然气的光学热值H O，H O＝H T-X，式中，H T表示理论热值，X表示光学杂质干扰；
声速传感模用于检测得到天然气的热传导热值H hc，H hc＝HT-Y，式中，H T表示理论热值，Y表示热传导杂质干扰，且有Y＝aX，a为常数系数；
计算模块通过下式(1)计算得到天然气单位发热量H：
H＝H O-(H O-H hc)÷(1-a)    (1)
计算单元，用于计算得到天然气的能量E，E＝Q n×H。
优选地，所述体积流量测量单元包括体积流量测量模块及修正模块，其中：
体积流量测量模块用于测量得到未经修正的体积流量Q g；
修正模块基于下式(2)对体积流量Qg进行修正，得到所述体积流量Qn：
Figure PCTCN2021083835-appb-000001
式(2)中，P g表示由修正模块测量得到的天然气绝对压力，P n表示标准大气压，T n表示天然气标准状态下的绝对温度，T g表示由修正模块测量得到的天然气绝对温度，Z n表示天然气标准状态下的介质压缩系数，Z g表示天然气工作状态下的介质压缩系数。
优选地，所述计算单元集成在所述修正模块内。
优选地，所述热值检测单元将得到的所述天然气单位发热量H通过数据线发送给所述修正模块，由所述修正模块输出所述能量E。
优选地，还包括进气单元、气体过滤单元及减压单元，天然气通过进气单元进入气体过滤单元，由气体过滤单元滤除天然气中的杂质，经过过滤的天然气通过减压单元减压至目标压力值后再被送入所述热值检测单元及所述体积流量测量模块。
本发明提供的一种流量计所采用的计算能量E的计算方法较为简单，因此可以实现对天然气能量E快速、准确的计量。
附图说明
图1为实施例中公开的燃气能量计量流量计的示意图；
图2为实施例中公开的燃气能量计量流量计的内部结构示意图；
图3为实施例中的热值仪的原理图，图中：
1-流量计，2-体积修正仪，3-进气接头，4-进气阀，5-过滤器，6-减压阀，7-热值仪，8-单向阀，9-RS485通讯线缆，10-LED光源，11-平面镜，12-凸镜，13-干涉条纹，14-棱镜，15-平行镜，16-声源，17-接收器，18-燃气入口，19-燃气出口。
具体实施方式
下面结合具体实施例，进一步阐述本发明。应理解，这些实施例仅用于说明本发明而不用于限制本发明的范围。此外应理解，在阅读了本发明讲授的内容之后，本领域技术人员可以对本发明作各种改动或修改，这些等价形式同样落于本申请所附权利要求书所限定的范围。
如图1及图2所示，本实施例公开的一种燃气能量计量流量计包括体积修正仪1(本实施例采用EVC智能体积修正仪)、流量计2、进气接头3、进气阀4、过滤器5、减压阀6、热值仪7、单向阀8及RS485通讯线缆9。
进气接头3与流量计2的外壳连接，天然气进入流量计2后，还通过进气接头3及4进气阀进入到过滤器5中。由过滤器5滤除天然气中的气体杂质后，经过过滤的天然气经减压阀6减压到2-10KPa后进入到热值仪7中，热值仪7测量得到天然气单位发热量H(单位为MJ/Nm 3)。热值仪7通过modbus协议(包括RS485、RS232)进行数据通讯，将天然气单位发热量H传给体积修正仪1。体积修正仪1同时根据流量计2输出的体积流量Q g计算得到天然气的能量E(单位为MJ)，并将计算的结果显示在液晶屏上。
从原理上来说，天然气的能量E就是天然气体积流量和单位发热量的乘积。也就是说，天然气的能量取决于两个因素：天然气体积流量和单位发热量。天然 气的能量流量计量是通过两个不相关的测量来完成的，即体积或质量流量的测量和体积或质量发热量的测量，将这两种测量合成计算出天然气的能量，如下式(1)所示：
E＝Q n×H    (1)
式(1)中，Q n为天然气标准状态的体积流量或质量流量，单位为Nm 3或kg。
天然气的体积流量Q n采用气体腰轮流量计、气体涡轮流量计或气体超声波流量计进行测量。本实施例以气体腰轮流量计来说明。
随着气体的流动，在仪表的进出口产生一个差压，这个差压作用在通过高精度、同步齿轮连接的腰轮上，产生了一个转矩。这个转矩依次作用在一对腰轮上，使之旋转。在壳体和腰轮之间，没有接触。这样在壳体和腰轮之间形成的计量室周期性的充满和排空。腰轮的转数与通过仪表的气体体积量成正比。转子的转数通过磁电转换装置转换为脉冲信号。
本实施例在精密制造机械表的基础上配置修正仪1，修正仪1由温度和压力检测通道及处理单元组成，并配有输入、输出接口。修正仪1中的处理单元按照气态方程进行体积换算，并自动进行压缩因子修正，气态方程如下式(2)所示：
Figure PCTCN2021083835-appb-000002
式(2)中，P g表示由修正模块测量得到的天然气绝对压力，单位为kPa；
P n表示标准大气压，101.325kPa；
T n表示天然气标准状态下的绝对温度，293.15K(20℃)；
T g表示由修正模块测量得到的天然气绝对温度；
Z n表示天然气标准状态下的介质压缩系数；
Z g表示天然气工作状态下的介质压缩系数。
注：对于天然气Z n/Z g＝(FZ) 2，FZ为超压缩因子，按中国石油天然气总公司的标准SY/T6143-1996中的公式进行计算。
如图3所示，本实施例中的热值仪7采用光学热值检测+热传导热值检测的组合式计算方法。杂质成分对光学热值检测的干扰和杂质成分对热传导热值检测的干扰有个近似常数a，则有：
通过光学热值检测获得的光学热值H O，H O＝H T-X，式中，H T表示理论热值，X表示光学杂质干扰。
热传导热值检测获得的热传导热值H hc，H hc＝H T-Y，式中，H T表示理论热值，Y表示热传导杂质干扰，且有Y＝aX。
最终整理得到下式(3)：
H＝H O-(H O-H hc)÷(1-a)    (3)
体积修正仪1利用上式(1)、(2)、(3)计算得到天然气的能量E，并将其显示到液晶屏上。

Claims (5)

  1. 一种燃气能量计量流量计，其特征在于，包括：
    体积流量测量单元，用于测量得到天然气的体积流量Q n；
    热值检测单元，用于检测天然气单位发热量H，包括光学传感模块、声速传感模及计算模块，其中：
    光学传感模块用于检测得到天然气的光学热值H O，H O＝H T-X，式中，H T表示理论热值，X表示光学杂质干扰；
    声速传感模用于检测得到天然气的热传导热值H hc，H hc＝H T-Y，式中，H T表示理论热值，Y表示热传导杂质干扰，且有Y＝aX，a为常数系数；
    计算模块通过下式(1)计算得到天然气单位发热量H：
    H＝H O-(H O-H hc)÷(1-a)   (1)
    计算单元，用于计算得到天然气的能量E，E＝Q n×H。
  2. 如权利要求1所述的一种燃气能量计量流量计，其特征在于，所述体积流量测量单元包括体积流量测量模块及修正模块，其中：
    体积流量测量模块用于测量得到未经修正的体积流量Q g；
    修正模块基于下式(2)对体积流量Q g进行修正，得到所述体积流量Q n：
    Figure PCTCN2021083835-appb-100001
    式(2)中，P g表示由修正模块测量得到的天然气绝对压力，P n表示标准大气压，T n表示天然气标准状态下的绝对温度，T g表示由修正模块测量得到的天然气绝对温度，Z n表示天然气标准状态下的介质压缩系数，Z g表示天然气工作状态下的介质压缩系数。
  3. 如权利要求2所述的一种燃气能量计量流量计，其特征在于，所述计算单元集成在所述修正模块内。
  4. 如权利要求3所述的一种燃气能量计量流量计，其特征在于，所述热值检测单元将得到的所述天然气单位发热量H通过数据线发送给所述修正模块，由所述修正模块输出所述能量E。
  5. 如权利要求4所述的一种燃气能量计量流量计，其特征在于，还包括进气单元、气体过滤单元及减压单元，天然气通过进气单元进入气体过滤单元，由气体过滤单元滤除天然气中的杂质，经过过滤的天然气通过减压单元减压至目标压力值后再被送入所述热值检测单元及所述体积流量测量模块。
PCT/CN2021/083835 2020-11-19 2021-03-30 一种燃气能量计量流量计 WO2022105081A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202011298277.9 2020-11-19
CN202011298277.9A CN112414592A (zh) 2020-11-19 2020-11-19 一种燃气能量计量流量计

Publications (1)

Publication Number Publication Date
WO2022105081A1 true WO2022105081A1 (zh) 2022-05-27

Family

ID=74773395

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/083835 WO2022105081A1 (zh) 2020-11-19 2021-03-30 一种燃气能量计量流量计

Country Status (2)

Country Link
CN (1) CN112414592A (zh)
WO (1) WO2022105081A1 (zh)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112414592A (zh) * 2020-11-19 2021-02-26 上海真兰仪表科技股份有限公司 一种燃气能量计量流量计
CN114323164B (zh) * 2021-11-24 2024-04-19 北京市燃气集团有限责任公司 一种用于燃气用户的实时在线能量计量方法和系统
CN114414619B (zh) * 2022-01-19 2023-08-15 成都秦川物联网科技股份有限公司 嵌有信息安全管理模块的能量计量装置及物联网系统

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1384342A (zh) * 2002-05-21 2002-12-11 田宏杰 智能型气体流量计
EP1391703A1 (de) * 2002-08-22 2004-02-25 Abb Research Ltd. Thermisches Gasdurchfluss-Messgerät mit Gasqualitätsindikator
CN106706064A (zh) * 2017-02-15 2017-05-24 山东大学 一种民用燃气能量计量装置及方法
CN111328372A (zh) * 2019-01-17 2020-06-23 理研计器株式会社 组成分析装置及组成分析方法
CN211786720U (zh) * 2019-11-26 2020-10-27 山东思达特测控设备有限公司 一种用于天然气能量计量装置的能量积算模块
CN112414592A (zh) * 2020-11-19 2021-02-26 上海真兰仪表科技股份有限公司 一种燃气能量计量流量计

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103542904B (zh) * 2013-10-29 2017-01-04 成都千嘉科技有限公司 基于能量计量的燃气计量方法及装置
CN104197984B (zh) * 2014-08-21 2017-01-18 天信仪表集团有限公司 一种燃气能量计量方法
CN211234569U (zh) * 2019-11-26 2020-08-11 山东思达特测控设备有限公司 一种天然气热值计量装置
CN111238591A (zh) * 2020-01-20 2020-06-05 广州燃气集团有限公司 燃气计量系统的温压补偿校核方法、系统和存储介质

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1384342A (zh) * 2002-05-21 2002-12-11 田宏杰 智能型气体流量计
EP1391703A1 (de) * 2002-08-22 2004-02-25 Abb Research Ltd. Thermisches Gasdurchfluss-Messgerät mit Gasqualitätsindikator
CN106706064A (zh) * 2017-02-15 2017-05-24 山东大学 一种民用燃气能量计量装置及方法
CN111328372A (zh) * 2019-01-17 2020-06-23 理研计器株式会社 组成分析装置及组成分析方法
CN211786720U (zh) * 2019-11-26 2020-10-27 山东思达特测控设备有限公司 一种用于天然气能量计量装置的能量积算模块
CN112414592A (zh) * 2020-11-19 2021-02-26 上海真兰仪表科技股份有限公司 一种燃气能量计量流量计

Also Published As

Publication number Publication date
CN112414592A (zh) 2021-02-26

Similar Documents

Publication Publication Date Title
WO2022105081A1 (zh) 一种燃气能量计量流量计
CN107238424B (zh) 一种循环式气体涡轮流量计的检测装置及检测方法
CN103542904A (zh) 基于能量计量的燃气计量方法及装置
CN202869570U (zh) 一体化孔板式流量计
CN202471153U (zh) 智能型气体腰轮流量计
CN108709594A (zh) 一种气体流量计及气体流量测量方法
CN106134436B (zh) 航天器推进剂气体流量测量装置
CN103206997B (zh) 气体罗茨流量测量装置及其流量修正方法
CN115064737B (zh) 一种燃料电池氢气使用累积量的监控方法
CN213456654U (zh) 热值燃气表
CN210071019U (zh) 一种智能气体超声波流量计
CN112923985B (zh) 采用积算仪方式的电子式膜式燃气表
CN211904339U (zh) 一种小流量气体流量计用在线检测标准装置
CN208350144U (zh) 一种气体流量计
CN114547892A (zh) 基于液膜流动参数建模的涡街湿气分相流量测量方法
CN210037021U (zh) 一种用于燃气仪表热量计量的装置
JPS5540223A (en) Engine intake air measuring device
CN108132078A (zh) 一种基于分流计量装置的超声波燃气表
CN205981308U (zh) 卫生型小口径差压流量计
CN204831443U (zh) 水表、热量表、流量计用测量管段体与转换器的连接结构
CN206056692U (zh) 一种装有多旁路测量装置的mems热式质量燃气表
CN2338734Y (zh) 热式质量流量传感器
CN212482588U (zh) 一种旋进旋涡差压式质量流量计
CN214471099U (zh) 一种燃气流量传感器及燃气计量表
Ferguson et al. Further studies of pulsatile flow through an orifice

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21893239

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21893239

Country of ref document: EP

Kind code of ref document: A1