CN1760661A - Method for measuring relative velocity between medium and surface of metal, and device utilized - Google Patents
Method for measuring relative velocity between medium and surface of metal, and device utilized Download PDFInfo
- Publication number
- CN1760661A CN1760661A CN 200510044623 CN200510044623A CN1760661A CN 1760661 A CN1760661 A CN 1760661A CN 200510044623 CN200510044623 CN 200510044623 CN 200510044623 A CN200510044623 A CN 200510044623A CN 1760661 A CN1760661 A CN 1760661A
- Authority
- CN
- China
- Prior art keywords
- electrode
- medium
- input terminal
- flow
- current density
- 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.)
- Pending
Links
Images
Landscapes
- Testing Resistance To Weather, Investigating Materials By Mechanical Methods (AREA)
Abstract
Outer electrode of flow transducer is put into medium to be tested. Using dual potentiostat carries out cathodic polarization in order to measure ratio of limit current density between outer id and inner id in media with different velocities of flow as well as to make working curve between velocity of flow and ratio of current density. Then, based on measured ratio of current density and the working curve obtains relative flow rate of medium to surface of metal. The flow transducer includes outer electrode and inner electrode. Outer electrode and inner electrode respectively include working electrode, auxiliary electrode and reference electrode, which are constituted from circular or quadrate platinum sheet or stainless steel sheet. Advantages are: easy of implementation, reliable and estimating speed of metallic corrosion directly.
Description
Technical field
The present invention relates to a kind of method and equipment therefor of measuring medium at the metal surface relative velocity.
Background technology
Velocity of medium has great influence to metal erosion speed, measures and estimates metal erosion speed and must measure the relative velocity of medium in the metal surface.For the relative velocity of metal surface motion, with the media flow orientation independent, what promptly need to measure only is a scalar to the just medium that influences metal erosion speed in several millimeters scopes.But current widely used velocity of medium determining instrument all is the flow velocity and the flow direction of measuring with respect to the medium integral body of a certain fixed reference, and it is not suitable for the metal surface media flow speed of the interior independent of direction of distance among a small circle of measuring.Do not see at present yet measure medium the metal surface among a small circle in the method for relative scalar flow velocity.
Summary of the invention
The purpose of this invention is to provide a kind of medium of measuring at the electrochemical method of metal surface relative velocity and used device, it can satisfy
The demand of prior art.
A kind of method of measuring medium at the metal surface relative velocity is characterized in that the external electrode of flow sensor is put into testing medium, and carries out cathodic polarization with double potentiostat, measures cathode limit current density ratio i in the different in flow rate medium
Outside the d/ i
In the d, and make the working curve that concerns between flow velocity and the close ratio of electric current, draw the relative velocity value of medium according to the current density ratio of measuring and this working curve then in the metal surface.
Implement the used device of said method, it is characterized in that forming by flow sensor and double potentiostat, this flow sensor has external electrode and interior electrode, and external electrode and interior electrode are made of working electrode, auxiliary electrode and the contrast electrode that 3 circles or square platinized platinum or stainless steel substrates are formed respectively; 3 electrodes in the interior electrode connect working electrode input terminal W1, auxiliary electrode input terminal C1 and the contrast electrode input terminal R1 of double potentiostat respectively; 3 electrodes in the external electrode connect working electrode input terminal W2, auxiliary electrode input terminal C2 and the contrast electrode input terminal R2 of double potentiostat respectively.
Advantage of the present invention: it is simple to measure force method, reliable, and the result can be directly used in the metal erosion speed of estimating.This method has remedied the blank of estimating the important parameter assay method of metal erosion speed.
Description of drawings
Accompanying drawing 1 is an apparatus structure synoptic diagram of the present invention.
Accompanying drawing 2 is the structural representation of looking up of its flow sensor.
The working curve of accompanying drawing 3 for concerning between flow velocity and the close ratio of electric current.
Embodiment
The oxygen reduction reaction limiting current density is in the medium
i
d＝nFDδ
-1
Wherein, δ=f (v) i
dBe the oxygen reduction reaction limiting current density; N is the oxygen reduction reaction electron number; F is a Faraday constant; D is the coefficient of diffusion of oxygen molecule in medium; δ is a thickness of diffusion layer, is the function of flow velocity v.N in the formula, F, D is constant, so limiting current density i
dOnly relevant with thickness of diffusion layer δ.Because thickness of diffusion layer δ increases with velocity of medium and reduces, so can pass through determination limit current density i
dCalculate thickness of diffusion layer δ, and then calculation medium surface relative velocity.Can be by measuring platinum electrode cathodic polarization curve acquisition limiting current density i in the medium
d
Mensuration medium of the present invention is made up of flow sensor 4 and double potentiostat 1 at the device of metal surface relative velocity, flow sensor 4 has external electrode 2 and interior electrode 3, and working electrode, auxiliary electrode and contrast electrode that external electrode 2 and interior electrode 3 are formed by the circle platinized platinum constitute.External electrode 2 is directly exposed in the flow media during use, and its surface state is influenced by velocity of medium directly, and interior electrode 3 is arranged near the circular deep hole bottom flow sensor 4 external electrodes 2, and its surface dielectric remains static.3 electrodes in the interior electrode 3 connect the working electrode input terminal W1 of double potentiostat 1 respectively, auxiliary electrode input terminal C1 and contrast electrode input terminal R1; 3 electrodes in the external electrode 2 connect the working electrode input terminal W2 of double potentiostat 1 respectively, auxiliary electrode input terminal C2 and contrast electrode input terminal R2.If use the inside and outside electrode 3,2 in 1 pair of flow media of double potentiostat to carry out identical reinforcing yin essence utmost point polarization, then its cathode-current density ratio satisfies following formula
Because interior electrode 3 lip-deep flow velocitys are zero, so f ' (v
In) remaining unchanged in the mensuration process is constant.Therefore, the cathode limit current density ratio i of the flow sensor 4 of mensuration
Outside the d/ i
In the dWith flow velocity v to be determined
OutwardThere is the funtcional relationship of determining.The cathode limit current density ratio i of flow sensor 4 when measuring known flow rate in advance
Outside the d/ i
In the d, and make cathode limit current density ratio i
Outside the d/ i
In the dWith the working curve of flow velocity, as shown in Figure 3.
During operation the external electrode of flow sensor 4 is put into testing medium water, make the medium parallel-flow cross external electrode 2 surfaces, carry out cathodic polarization, measure cathode limit current density ratio i in the different in flow rate medium with double potentiostat 1
Outside the d/ i
In the d, obtain the relative velocity value of medium according to the working curve that concerns between cathode limit current density ratio of measuring and the flow velocity then in the metal surface.For example, if the cathode limit current density ratio i of the sensor of measuring
Outside the d/ i
In the dBe 3, the relative velocity of finding metal surface this moment from above-mentioned working curve is 4 meter per seconds.This flow velocity then be directly and metal erosion speed the physical quantity of substantial connection is arranged.
Claims (2)
1. a method of measuring medium at the metal surface relative velocity is characterized in that the external electrode of flow sensor is put into testing medium, and carries out cathodic polarization with double potentiostat, measures cathode limit current density ratio i in the different in flow rate medium
Outside the d/ i
In the d, and make the working curve that concerns between flow velocity and the close ratio of electric current, draw the relative velocity value of medium according to the current density ratio of measuring and this working curve then in the metal surface.
2. implement the used device of the described method of claim 1, it is characterized in that forming by flow sensor (4) and double potentiostat (1), this flow sensor (4) has external electrode (2) and interior electrode (3), and external electrode (2) and interior electrode (3) are made of working electrode, auxiliary electrode and the contrast electrode that 3 circles or square platinized platinum or stainless steel substrates are formed respectively; 3 electrodes in the interior electrode (3) connect working electrode input terminal W1, auxiliary electrode input terminal C1 and the contrast electrode input terminal R1 of double potentiostat (1) respectively; 3 electrodes in the external electrode (2) connect working electrode input terminal W2, auxiliary electrode input terminal C2 and the contrast electrode input terminal R2 of double potentiostat (1) respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510044623 CN1760661A (en) | 2005-09-01 | 2005-09-01 | Method for measuring relative velocity between medium and surface of metal, and device utilized |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510044623 CN1760661A (en) | 2005-09-01 | 2005-09-01 | Method for measuring relative velocity between medium and surface of metal, and device utilized |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1760661A true CN1760661A (en) | 2006-04-19 |
Family
ID=36706811
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200510044623 Pending CN1760661A (en) | 2005-09-01 | 2005-09-01 | Method for measuring relative velocity between medium and surface of metal, and device utilized |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1760661A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109946477A (en) * | 2019-01-30 | 2019-06-28 | 北京师范大学 | A kind of apparatus for measuring liquid flow speed and measurement method based on conductive electrode electrochemical response |
-
2005
- 2005-09-01 CN CN 200510044623 patent/CN1760661A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109946477A (en) * | 2019-01-30 | 2019-06-28 | 北京师范大学 | A kind of apparatus for measuring liquid flow speed and measurement method based on conductive electrode electrochemical response |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Libansky et al. | Basic electrochemical properties of sputtered gold film electrodes | |
| Bučková et al. | Adsorptive stripping voltammetric detection of daunomycin at a bismuth bulk electrode | |
| Figueiredo-Filho et al. | Inexpensive and disposable copper mini-sensor modified with bismuth for lead and cadmium determination using square-wave anodic stripping voltammetry | |
| Bastos et al. | Localised measurements of pH and dissolved oxygen as complements to SVET in the investigation of corrosion at defects in coated aluminum alloy | |
| Xu et al. | Voltammetric microelectrodes for biocorrosion studies | |
| Xu et al. | A 3D porous graphene aerogel@ GOx based microfluidic biosensor for electrochemical glucose detection | |
| Chao et al. | Graphene-modified electrode for the selective determination of uric acid under coexistence of dopamine and ascorbic acid | |
| Chou et al. | A Nonenzymatic Glucose Sensor Using Nanoporous Platinum Electrodes Prepared by Electrochemical Alloying/Dealloying in a Water‐Insensitive Zinc Chloride‐1‐Ethyl‐3‐Methylimidazolium Chloride Ionic Liquid | |
| Li et al. | Phosphate sensor using molybdenum | |
| Bastos et al. | Micropotentiometric mapping of local distributions of Zn2+ relevant to corrosion studies | |
| CN105452855A (en) | Electrochemical-based analytical test strip with a soluble electrochemically-active coating opposite a bare electrode | |
| CN101187644A (en) | Method for determining metal polarization curve under thin liquid layer and the device therefor | |
| Zhao et al. | Simultaneous electrochemical determination of uric acid and ascorbic acid using L-cysteine self-assembled gold electrode | |
| Sochr et al. | Heavy metals determination using various bismuth film modified carbon-based electrodes | |
| Wang et al. | All solid‐state pH electrode based on titanium nitride sensitive film | |
| Pourghobadi et al. | Voltammetric determination of dopamine using modified glassy carbon electrode by electrografting of catechol | |
| Tufa et al. | Electrochemical determination of lead using bismuth modified glassy carbon electrode | |
| Moreno et al. | Cathodic electrochemical determination of herbicides in acid media using a bismuth film electrode | |
| Maile et al. | Evaluation of corrosion and protection of coated metals with local ion concentration technique (LICT) | |
| Devlin et al. | Novel pH sensor based on anthraquinone–ferrocene modified free standing gold nanowire array electrode | |
| CN1760661A (en) | Method for measuring relative velocity between medium and surface of metal, and device utilized | |
| Culková et al. | Boron-Doped Diamond Electrode as Sensitive and Selective Green Electroanalytical Tool for Heavy Metals Environmental Monitoring: Zinc Detection in Rubber Industry Waste. | |
| Sun et al. | Electrochemistry and Voltammetric Determination of Adenosine with N‐Hexylpyridinium Hexafluorophosphate Modified Electrode | |
| Yin et al. | A batch microfabrication of a microfluidic electrochemical sensor for rapid chemical oxygen demand measurement | |
| Li et al. | Developing an iridium oxide film modified microelectrode for microscale measurement of pH |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |