EP2452182A1 - Filtre d'antenne rf comme capteur de mesure d'un fluide - Google Patents

Filtre d'antenne rf comme capteur de mesure d'un fluide

Info

Publication number
EP2452182A1
EP2452182A1 EP10734566A EP10734566A EP2452182A1 EP 2452182 A1 EP2452182 A1 EP 2452182A1 EP 10734566 A EP10734566 A EP 10734566A EP 10734566 A EP10734566 A EP 10734566A EP 2452182 A1 EP2452182 A1 EP 2452182A1
Authority
EP
European Patent Office
Prior art keywords
fluid
filter
antenna
measuring
conductor
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
EP10734566A
Other languages
German (de)
English (en)
Inventor
Mateo Jozef Jacques Mayer
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Smart Frequencies BV
Original Assignee
Smart Frequencies BV
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 Smart Frequencies BV filed Critical Smart Frequencies BV
Publication of EP2452182A1 publication Critical patent/EP2452182A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N22/00—Investigating or analysing materials by the use of microwaves or radio waves, i.e. electromagnetic waves with a wavelength of one millimetre or more
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/18—Water

Definitions

  • the present invention relates to an antenna filter for measuring a fluid. More specifically, the filter is used for measuring properties of a fluid, like drinking water.
  • the antenna filter for measuring a fluid according to the invention, the antenna filter comprising:
  • first conductor wherein the distance between the first and second conductors defines a volume that in use holds the fluid to achieve a fluid containing transmission line.
  • the volume between the at least two conductors can be filled with a fluid.
  • the fluid defines a fluid containing transmission line, preferably transmitting a radio frequency signal.
  • the filter comprises a fluid, like water, as dielectricum between the conductors.
  • the characteristics of such filter depend, amongst other things, on the dielectric constant of the fluid. This constant is influenced by the presence of small solid particles, bacteria and also dissolved compounds. This influence can be determined by comparing the supplied broad radio frequency spectrum to the filter with the outgoing signal, for example, preferably as function of time.
  • the antenna filter according to the invention can be used to characterize properties of this fluid, or fluid sample, by measuring the response by a receiver on an input signal from a transmitter.
  • a receiver on an input signal from a transmitter.
  • the dielectric permittivity of the fluid can be deduced from the measured response.
  • the determined dielectric permittivity of the fluid between the first and second conductor is correlated to specific
  • the senor will be able to detect aggregates of molecules, such as primary crystals and can be useful to monitor and control crystallization and scaling processes, for example. This results in an effective and efficient manner to measure such fluid.
  • the concentrations of the detected components in the fluid can be determined with the antenna filter according to the present invention as
  • the first conductor is provided as a co-axial cable with a solid metal or tubing. This first conductor is surrounded by the second conductor comprising a metal tubing. This results in a relatively compact antenna filter of a co-axial type.
  • the characteristic impudent of the transmission line is calculated from the diameters of the first inner conductor and second outer conductor with a dielectric permittivity of insulating material
  • Particles and/or molecules each have a specific response to changes in the electric field. This enables measurement of a fluid in an effective and efficient manner.
  • the antenna filter is an open line quarter wave length co-axial antenna filter.
  • the filter By providing the filter as a quarter wave length open line co-axial filter, changes in fluid composition can be detected. This is achieved as the resonant frequency of the filter depends on the length of this filter and the dielectric between the first and second conductor, i.e., on the dielectric properties of the fluid between the
  • the quarter wave length antenna filter is
  • the filter comprises an open end.
  • Such open line filter that in use is filled with fluid, behaves like a series resonant circuit. Therefore, at resonance, this filter has minimum impedance resulting in "short- circuit" of the signal supplied by the function generator.
  • this generator has an internal resistance that is often not negligible, the short-circuit at resonance will result in a potential drop over the system. This drop can be measured by a spectrum analyzer. This results in an
  • the inner and/or outer conductors are insulated.
  • the sensitivity of the filter for the measurement of the fluid is improved significantly.
  • the detection levels of components in the fluid can be relatively low.
  • the filter further comprises a dielectric for adsorbing components in a fluid.
  • the sensitivity of the filter can be increased significantly.
  • dielectrics adsorb components that are present in the fluid, like water.
  • the dielectric comprises an ion exchange resin.
  • this ion exchange resin is provided as spherical particles with a diameter in the range of about 0.1 mm tot 2.5 mm.
  • Such particles can be provided as a dielectric between the first and second conductor of the filter. The particles will adsorb components that are present in the water.
  • the fluid feed to the filter is stopped and a detailed analysis of the complex dielectric permittivity as function of frequency can be performed.
  • the observed dielectric behaviour is correlated to the type and concentration of adsorbed components to the particles. This means that the detection levels for the filter for detecting the presence of a specific component in the fluid is lowered.
  • other dielectrics with specific adsorption properties can be applied as alternative to the ion exchange resin.
  • the antenna filter is a flow-through filter.
  • Providing the filter as a flow-through filter enables on-line measurement of a fluid, thereby preventing the taking of samples of such fluids.
  • such flow- through filter is used in an advantageous manner.
  • the particles will gradually adsorb components that are present in the fluid. This not only prevents the taking of samples, it also further minimizes the detection levels of components in the fluid.
  • the present invention also relates to a sensor system for measuring a fluid, the system comprising:
  • the transmitter provides an input signal, preferably as a broad radio frequency
  • the transmitter and receiver are connected through a transmission line.
  • the response is a measure of properties of the fluid, like the dielectric permittivity thereof.
  • the measurement can be correlated to the presence of components, and possibly also the concentrations thereof, in the fluid. This provides an effective and efficient sensor system.
  • the present invention further also relates to a method for measuring a fluid, the method comprising the steps of:
  • the method By measuring the response of the supplied signal, an indication of at least some of the properties of the fluid is achieved.
  • the properties of the fluid comprise the dielectric constant of this fluid.
  • FIG. 1 illustrates a schematic overview of the filter according to the present invention
  • FIG. 2 illustrates a schematic overview of a sensor system according to the present invention
  • a filter 2 ( Figure 1) comprises a co-axial cable 4.
  • Cable 4 comprises a solid metal or tubing 6 that is insulated.
  • Metal or tubing 6 acts a conductor.
  • Around cable 4 is provided a metal tubing 8 that acts as another
  • Tubing 8 is provided at a distance of cable 4. This distance defines a volume 10 between conductors 6, 8 that in use is at least partially filled by a fluid to be measured.
  • a sensor system 12 ( Figure 2) comprises a transmitter 14 that is connected to a receiver 16 through a transmission line 18.
  • Transmission line 18 is connected to the earth 20.
  • Transmission line 18 is further connected to a filter 22.
  • Filter 22 comprises a first conductor 24 that is insulated with insulation material 26 and a second conductor 28.
  • the volume 30 between the conductors 24, 28 is filled with fluid 32.
  • Circuit 34 comprises a function generator 36 and a resistance (Rl) 40. Circuit 34 further comprises filter 42 with a capacitor (C3) 44, inductor (L3) 46 and a resistance (R2) 48. Measurements are performed with a spectrum analyzer 50 comprising a
  • Capacitors (Cl) 56 and (C2) 58 represent, together with inductors (Ll) 60 and (L2) 62 the 50 Ohm co-axial line from the function generator to the open line filter.
  • Capacitors (C4) 64 and (C5) 66 represent, together with inductors (L4) 68 and (L5) 70, the 50 Ohm co- axial line from the filter to the analyzer.
  • the open line co-axial cable that can be filled with a fluid behaves like a series resonant circuit.
  • This means that this open line co-axial cable has minimum impedance and resonance, resulting in short-circuit of the signals supplied by the function generator.
  • the function generator has a significant internal resistance, such short- circuit and resonance will result in a potential drop over resistor (R3) that can be measured by the spectrum analyzer 50.
  • R3 potential drop over resistor
  • the resonant frequency of the filter 42 depends also on the dielectric between inner and outer conductors 24, 32 changes in the water composition will result in changes of the resonant frequency.
  • the dielectric permittivity of the fluid can be determined. This dielectric permittivity is correlated to one or more specific
  • the amplitude of the measured signal by the spectrum analyzer was measured as function of frequency.
  • Figure 4 shows the amplitude versus frequency plot with air and sunflower oil as dielectric in the filter, with the frequency in MHz and the amplitude in mV with measured results for air being indicated with triangles, and for sunflower oil indicated with squares. From the results, it can be seen that the difference between air and sunflower oil, although the relative dielectric permittivities of both substances are relatively close to each other, can be detected.
  • Measured base resonant frequency for air is 590 MHz and for sunflower oil 400 MHz.
  • Figure 5 shows results of a similar experiment with tap water (indicated with squares) and ethanol
  • the measured base resonant frequencies for tap water is 210 MHz and for ethanol 220 MHz with the peaks of the next harmonic considerably different for both fluids, i.e. for tap water 620 MHz and for ethanol 720 MHz.
  • Figures 6 - 9 show results of an amplitude versus frequency plot for tap water (indicated with squares) and tap water with different concentrations of dissolved sodium chlorite (diamonds indicating 0.0427 mol/L NaCl solution, triangles pointing downwards 0.855 mol/L NaCl, triangles pointing upwards 5.128 mol/L NaCl.
  • the frequencies are shown in MHz and the amplitude in mV.
  • Figure 6 illustrates an overview of the measured responses
  • Figure 7 zooms in on the frequency range of 100 - 300 MHz
  • Figure 8 to 500 - 800 MHz and Figure 9 to 850 - 1150 MHz. From the results can be concluded that differences between tap water and water containing different amounts of sodium chlorite can be detected with the filter according to the present invention.
  • Figure 7 shows that in the frequency range of 100 - 300 MHz the resonant frequency of the filter decreases with increasing salt concentration in the water. It is also shown that a minimum of the
  • Figure 11 shows results of another amplitude versus frequency plot with the 25 mm diameter filter for both ethanol (indicated with diamonds) and tap water
  • Figure 12 shows an additional amplitude versus frequency plot for tap water (indicated with squares) and non-mixed tap water and ethanol (indicated with diamonds) and mixed tap water and ethanol (indicated with triangles), under similar conditions as previous experiments. As shown in this case, the differences between the different fluids can be detected. This indicates the influence of different process conditions under filter performance for measuring a fluid.
  • fingerprinting of a fluid can be done by supplying a broad array of frequencies spectrum to the filter and studying the outgoing signal, preferably as a function of time. From the dynamic response of the filter to changing water quality, it is possible to discriminate between solid particles, bacteria and dissolved components.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)

Abstract

La présente invention concerne un filtre d'antenne (2) destiné à mesurer un fluide. Le dispositif d'antenne comprend un premier conducteur (6) et un second conducteur (8) placé à une distance du premier conducteur, la distance entre le premier et le second conducteur (6, 8) définissant un volume (10) qui lors de l'utilisation garde le fluide de sorte à obtenir une ligne de transmission contenant un fluide.
EP10734566A 2009-07-06 2010-07-02 Filtre d'antenne rf comme capteur de mesure d'un fluide Withdrawn EP2452182A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL2003136A NL2003136C2 (en) 2009-07-06 2009-07-06 Antenna filter, sensor system and method for measuring a fluid.
PCT/NL2010/050423 WO2011005084A1 (fr) 2009-07-06 2010-07-02 Filtre d'antenne rf comme capteur de mesure d'un fluide

Publications (1)

Publication Number Publication Date
EP2452182A1 true EP2452182A1 (fr) 2012-05-16

Family

ID=41633209

Family Applications (1)

Application Number Title Priority Date Filing Date
EP10734566A Withdrawn EP2452182A1 (fr) 2009-07-06 2010-07-02 Filtre d'antenne rf comme capteur de mesure d'un fluide

Country Status (3)

Country Link
EP (1) EP2452182A1 (fr)
NL (1) NL2003136C2 (fr)
WO (1) WO2011005084A1 (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1038024C2 (nl) * 2010-06-09 2011-12-13 Smart Frequencies B V Werkwijze en inrichting voor fingerprinting of het behandelen van een dielectricum in het algemeen en van water in het bijzonder.
NL1039731C2 (en) * 2012-07-15 2014-01-16 Stichting Wetsus Ct Excellence Sustainable Water Technology Method and device for measuring dielectric properties of a fluidum using dipole antenna and/or wave guide cavity technology.
NL1039730C2 (en) * 2012-07-15 2014-01-16 Stichting Wetsus Ct Excellence Sustainable Water Technology Method and device for measuring dielectric properties of individual fluid samples present in an array of cavities in a stack of printed circuit boards.
NL1039732C2 (en) * 2012-07-15 2014-01-16 Stichting Wetsus Ct Excellence Sustainable Water Technology Method and device for measuring dielectric properties of a fluid and suppressing wave reflections.
NL1039729C2 (en) * 2012-07-15 2014-01-16 Stichting Wetsus Ct Excellence Sustainable Water Technology Method and device for measuring dielectric properties of a fluid through an array of cavities in a stack of printed circuit boards.
NL1041088B1 (en) * 2013-12-16 2016-05-19 Stichting Wetsus Centre Of Excellence For Sustainable Water Tech Method and device for measuring dielectric properties of a fluidum in a modified coaxial stub resonator.

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2110377B (en) * 1981-11-05 1986-01-29 Itt Ind Ltd Detecting water in hydrocarbon liquids
US4996490A (en) * 1986-11-18 1991-02-26 Atlantic Richfield Company Microwave apparatus and method for measuring fluid mixtures
US7556738B2 (en) * 2005-05-26 2009-07-07 Culligan International Company Method for determining the duration of a brine/slow rinse cycle for a water conditioner
DE102006034884A1 (de) * 2005-07-27 2007-04-05 Ademics Gbr Messgerät zur Bestimmung der elektromagnetischen Eigenschaften eines Fluids

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2011005084A1 *

Also Published As

Publication number Publication date
NL2003136C2 (en) 2011-01-10
WO2011005084A1 (fr) 2011-01-13

Similar Documents

Publication Publication Date Title
NL2003136C2 (en) Antenna filter, sensor system and method for measuring a fluid.
JP5666597B2 (ja) 固体及び流体の物体の成分の測定において使用するためのインピーダンス検知システム及び方法
US20200378903A1 (en) Detection system and detection method for water content and conductivity
CA2909068C (fr) Systeme et procede pour mesurer une fraction de volume dans des fluides multiphases
CN110763704B (zh) 基于微波Wire mesh的油水两相流含水率测量系统
EP3137888B1 (fr) Système de détection d'une interface dans un fluide multiphasique
WO2014051989A1 (fr) Systèmes de capteur pour mesure de niveau d'interface dans une composition de fluide polyphasique
CN101952713A (zh) 使用具有不同灵敏度深度的两个开端式同轴探头测量多相混合物中的液体的特性的系统和方法
CN211577013U (zh) 基于微波丝网传感器的油水两相流含水率测量系统
JP2001525059A (ja) 液体組成の評価
US20090267619A1 (en) Device and method for measuring an electrical property of a fluid flowing through a pipe
US8901939B2 (en) Open sensor for testing a split sample of a composite medium
WO2017112712A1 (fr) Systèmes de capteurs et méthodes de mesure de l'activité de l'argile
CN108680614A (zh) 双螺旋高频电容传感器高含水油水两相流持水率测量方法
CN101865873B (zh) 一种原油含水率电容电导式测试仪
CN201689071U (zh) 一种原油含水率电容电导式测试仪
CN111157591B (zh) 用于持水率测量的交错式双螺旋高频传感器及测量系统
CN2840073Y (zh) 一种插装式的电阻率电导率传感器
CN209690204U (zh) 一种含水率和电导率检测系统
NL1039730C2 (en) Method and device for measuring dielectric properties of individual fluid samples present in an array of cavities in a stack of printed circuit boards.
Ma et al. Inductance-based sensing technique for wireless, remote-query measurement in liquid media
Jain et al. Design of Complementary Meander Shaped Resonator for Adulteration Testing
Akhter et al. In-situ quality monitoring of amine in natural gas sweetening units using UHF probe
RU2037151C1 (ru) Диэлькометрический датчик для определения содержания воды и нефти в водонефтяной смеси
NL1039731C2 (en) Method and device for measuring dielectric properties of a fluidum using dipole antenna and/or wave guide cavity technology.

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20120203

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR

DAX Request for extension of the european patent (deleted)
17Q First examination report despatched

Effective date: 20121010

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20130423