CN202256257U - Two-phase flow water content testing device - Google Patents

Abstract

The utility model relates to a two-phase flow water content testing device. A coil system is embedded in the inner wall of a measuring duct; the coil system is composed of two transmitting coils and two receiving coils; the two transmitting coils are respectively connected with a transient signal generation circuit I and a transient signal generation circuit II; the receiving coils are connected with a transient signal acquisition and preprocessing circuit; the transient signal acquisition and preprocessing circuit is connected with a computer; when a two-phase fluid flows through the measuring duct, the transmitting coils are electrified by a pulse current; when the transmitting current suddenly drops to zero, a magnetic field and an electric field which suddenly change are generated around the transmitting coils; and in the pulse turn-off period, the receiving coils are utilized to receive secondary induced electromotive force generated by the oil/water two-phase flow in the measuring duct, and the response of the receiving coils is input into the computer for computing through the transient signal acquisition and preprocessing circuit. No matter the continuous phase in the two-phase flow is a conducting phase or nonconducting phase, the utility model can be used for measuring the water content, and can eliminate the influence of the primary fields.

Description

A kind of two-phase flow water cut test device

Technical field

The utility model relates to the field of measuring technique of oil, rock gas, particularly a kind of proving installation that is used to measure profit or air-water two phase flow water percentage.

Background technology

Profit and air-water two phase flow ubiquity in petroleum industry; And air water or oil-water two-phase flow detect a great problem that has become production logging; The ratio of accurately measuring oil, gas, water is for definite hierarchical production, and adjustment offtake strategy and controlling schemes have very important significance.The measuring method of oil, gas, water three-phase stream mainly contains at present: rays method, capacitance method, tomography method, conductance method, sonic method etc.

Rays method counting statistics error is bigger, and the sampling scope is little, has safety problem in the use.Reactance method; Comprise capacitance method, conductance method, tomography method; The oil-water ratio scope that can be suitable for is narrower, is not suitable for like capacitance method and ECT that conducting medium is the situation of external phase in the polyphasic flow, and conductance method and ERT are not suitable for the situation that non-conductive medium is an external phase.Therefore in actual production,, usually conductance method and capacitance method are used in combination, have caused the loaded down with trivial details of measuring equipment and control program in the production run in order to adapt to the variation of flow pattern.

In order to address the above problem, Chinese scholars is also being explored new multiphase flow measurement method.People such as Abdullah A.Kendoush also adopt autotransformer, apply the phase content in the high-frequency harmonic signal measurement oil-water two-phase flow.The author also once attempted adopting inductive coil series to carry out the measurement of water percentage in the polyphasic flow in 2009.But above-mentioned measuring system all adopts the harmonic emissions signal, and measuring process is vulnerable to the influence of directly coupling signal, makes the subsequent treatment and the trimming process more complicated of measuring-signal.

Summary of the invention

In order to overcome the defective of above-mentioned prior art; The purpose of the utility model is to provide a kind of proving installation of two-phase flow water percentage; Can overcome the two-phase flow water cut test device that the influence of inductive coil primary field can overcome conductance method and capacitance method defective simultaneously; No matter it can measure under situation of external phase to be conductive phase still be non-conductive phase at two-phase flow, the influence that can well remove primary field from the time simultaneously.

In order to achieve the above object, the utility model adopts following technical scheme:

A kind of two-phase flow water cut test device; Comprise a measuring channel 1; Be inlaid with coil system 10 on measuring channel 1 inwall, coil system 10 is made up of two groups of transmitting coils 11 and two group of received coils 12, and two group of received coils 12 are between two groups of transmitting coils 11; Formation is to sending out receiving; Two groups of transmitting coils 11 produce circuit I I 22 and link to each other with transient signal generation circuit I 21, transient signal respectively, and receiving coil 12 connects transient signal collection and pre-process circuits 30, and the transient signal collection links to each other with computing machine 40 with pre-process circuit 30.

The tube wall of said measuring channel 1 is a non-metal insulating material.

Said coil system 10 is four coil system structures, and transmitting coil 11 respectively comprises two coils with receiving coil 12, four coil symmetry settings at interval respectively, and wherein transmitting coil 11 is arranged on the outside of receiving coil 12, forms sending out receiving.

Described transient signal comprises unipolarity and bipolar square wave, trapezoidal wave, semisinusoidal shape ripple or triangular wave.

The utility model compared with prior art has following advantage:

1, the utility model can carry out measurement of water ratio to oil-water two-phase flow, air-water two phase flow, does not receive the influence of each phase ratio and flow pattern in the fluid.

2, the utility model adopts transient signal as transmitting, and can remove the influence of directly coupling signal from the time, and follow-up signal Processing and correction program are simple relatively.

3, the proving installation that the utility model provided can directly link to each other with oil pipeline, by Computer Processing and demonstration, can realize on-line measurement after its reception signal process collection and the pre-service.

Description of drawings

Fig. 1 is the measuring tube segment structure synoptic diagram of the utility model.

Fig. 2 is the water cut test device synoptic diagram of the utility model.

Embodiment

Be described in detail below in conjunction with the structural principle and the principle of work of accompanying drawing the utility model.

Like Fig. 1, shown in Figure 2; A kind of two-phase flow water cut test device comprises a measuring channel 1, is inlaid with coil system 10 on measuring channel 1 inwall; This inserted the smooth of measuring channel 1 inwall that guarantee; Flow pattern to two-phase flow in the measuring channel can not exert an influence, and coil system 10 is made up of two groups of transmitting coils 11 and two group of received coils 12, and two group of received coils 12 are between two groups of transmitting coils 11; Formation is to sending out receiving; Two groups of transmitting coils 11 produce circuit I I 22 and link to each other with transient signal generation circuit I 21, transient signal respectively, and receiving coil 12 connects transient signal collection and pre-process circuits 30, and the transient signal collection links to each other with computing machine 40 with pre-process circuit 30.The tube wall of measuring channel 1 is a non-metal insulating material, is used for retarder and is 10 electric signal.

The coil system 10 of the utility model is made up of 4 groups of independent coil T1 spaced apart, coil T2, coil R1, coil R2, and wherein coil R1 and R2 are receiving coil 12, and coil T1 and coil T2 are transmitting coil 11; Four coil symmetry settings at interval respectively, wherein transmitting coil 11 is arranged on the outside of receiving coil 12, forms sending out receiving; It is coil T1 emission; Coil R1 receives, coil T2 emission, and coil R2 receives.

Coil T1 is used to launch the pumping signal that transient signal generation circuit I 21 produces, and coil T2 is used to launch the pumping signal that transient signal generation circuit I I 22 produces.The transient signal generation circuit I 21 of the utility model design is identical with pulse height with the transient signal frequency of transient signal generation circuit I I 22 emissions, the time-delay 150ms that transmits of transient signal generation circuit I I 22 transient signal generation circuit I 21.Two transmitting coil T1 of the utility model design and T2, two receiving coil R1 form sending out receiving with R2, are used for two-phase fluid in the pipe in the responsive bigger zone, and the information about fluids that comprises in the feasible reception signal is abundanter.Each coil of coil system 10 is symmetrically distributed, and in the present embodiment, measuring the pipeline section internal diameter is 50mm, and two coil T1 of transmitting coil 11, the center of T2 are at a distance of 480mm, and the number of turn all is 700 circles.The center of receiving coil R1, R2 is at a distance of 160mm, and the number of turn all is 980 circles.Distance between each coil and the number of turn are different according to the measuring channel caliber; The distance and the number of turn at interval is also inequality; In practical application, spacing, the number of turn between each coil are set, and adjust, to reach best effect through test according to concrete caliber data.

As shown in Figure 2, the mechanism of the utility model Measurement of Two-phase water percentage is transient electromagnetic method.Transient electromagnetic method is on transmitting coil, to apply a steady current, continues to turn-off transmitter current after a period of time, measures the response on the receiving coil this moment.Transient signal generation circuit I 21 is used to produce bipolarity rectangle transient signal with transient signal generation circuit I I 22 in the present embodiment, as transmitting of transmitting coil T1, T2.When the fluid-mixing of oil-water two-phase flow flows through measuring channel; Transmitting coil 11 coil T1 and coil T 2 pass to pulse current; When transmitter current reduces to zero suddenly, in the oil-water two-phase flow around the transmitting coil 11, will produce magnetic field jumpy and electric field.During pulse-off, receive the secondary induction electromotive force that oil-water two-phase flow produces in the measuring channel through receiving coil R1, R2.Response on the receiving coil 12 is through the transient signal collection and pre-process circuit 30 amplifies, filtering, data acquisition etc., is input to computing machine 40 and handles.Computing machine 40 calculates the water percentage in the oil-water two-phase flow in the measuring channel according to the response on the receiving coil.It is the mature technology of this area with transient signal generation circuit I I 22 with transient signal collection and pre-process circuit 30 that transient signal produces circuit I 21, is not described in detail in this.

The theory of testing of the utility model is following:

Can obtain the frequency domain magnetic field intensity that produces in the tube fluid according to the Maxwell equation group:

$H_{z_1}\left(\mathrm{j\ω}\right)=-\frac{1}{2{\mathrm{\π}}^{2}j{\mathrm{\ω\μ}}_1}{\∫}_0^{\∞}{x_1}^2[j{\mathrm{\ω\μ}}_{1}m{K}_0\left(x_{1}r\right)+{\mathrm{aI}}_0\left(x_{i}r\right)]\cos \mathrm{\λ}(z-z_0)\mathrm{d\λ}$

Transient electromagnetic field is the transient process electromagnetic field that pulse current energising or outage form afterwards, establishes transmitter current

$I\left(t\right)=\left\{\begin{array}{c}I,t<0\\ 0,t\&GreaterEqual;0\end{array}\right.$

According to Gaver-Stehfest inverse laplace transform method, can obtain the time domain magnetic field intensity and express formula:

$H\left(t\right)=-\frac{\ln 2}{t}\underset{n=1}{\overset{12}{\mathrm{\&Sigma;}}}{k}_n\&CenterDot;\frac{H\left(s_n\right)}{s_n}$

The induction electromotive force that can obtain on the receiving coil is:

$U\left(t\right)=-N_R\underset{S}{\&Integral;\&Integral;}{\mathrm{\&mu;}}_1{H}_{z1}\&CenterDot;\mathrm{dS}$

$=-\frac{N_R{S}_R\&CenterDot;\ln 2}{2{\mathrm{\&pi;}}^{2}t}\underset{n=1}{\overset{12}{\mathrm{\&Sigma;}}}{k}_n\&CenterDot;{\&Integral;}_0^{\&infin;}{x_1}^2[{\mathrm{\&mu;}}_{1}m{K}_0\left(x_{1}r\right)+\frac{a}{s_n}{I}_0\left(x_{1}r\right)]\cos \mathrm{\&lambda;}(z-z_0)\mathrm{d\&lambda;}$

In the formula, a is the coefficient of being confirmed by boundary condition, I ₀(x _jR), I ₁(x _jR), K ₀(x _jR), K ₁(x _jR) be modified Bessel function, k _nBe Gaver-Stehfest conversion coefficient, s _n=n1n2/t,

μ ₁, ε ₁, σ ₁Be respectively magnetic permeability, specific inductive capacity, the conductivity of two-phase flow in the pipe.

Can find out from theoretical expression; Induction electromotive force on the receiving coil can reflect the electromagnetic parameter information of tube fluid; And each phase ratio difference of tube fluid has determined that the comprehensive parameters information of two-phase flow is different in the pipe, thereby can draw the distribution proportion information of tube fluid through the response of test receiving coil.

Can know that to sum up when the utility model passed through to measure oil-water two-phase flow through measuring channel, the response signal of receiving coil can obtain the water percentage in the oil-water two-phase flow.The utility model can be realized on-line measurement through Computer Processing and demonstration.The utility model can be applicable to the measurement of water percentage in the oil-water two-phase flow, perhaps other the measurement of the discrepant two-phase flow water percentage of conductivity such as air-water two phase flow.

Claims (4)

1. two-phase flow water cut test device; It is characterized in that, comprise a measuring channel (1), be inlaid with coil system (10) on measuring channel (1) inwall; Coil system (10) is made up of two groups of transmitting coils (11) and two group of received coils (12); Two group of received coils (12) are positioned between two groups of transmitting coils (11), form sending out receiving, and two groups of transmitting coils (11) produce circuit I (21) with transient signal respectively, transient signal produces circuit I I (22) and links to each other; Receiving coil (12) connects transient signal collection and pre-process circuit (30), and the transient signal collection links to each other with computing machine (40) with pre-process circuit (30).

2. a kind of two-phase flow water cut test device according to claim 1 is characterized in that the tube wall of measuring channel (1) is a non-metal insulating material.

3. a kind of two-phase flow water cut test device according to claim 1; It is characterized in that; Said coil system (10) is four coil system structures, and said transmitting coil (11) and receiving coil (12) respectively comprise two coils, four coil symmetry settings at interval respectively; Wherein transmitting coil (11) is arranged on the outside of receiving coil (12), forms sending out receiving.

4. a kind of two-phase flow water cut test device according to claim 1 is characterized in that, described transient signal comprises unipolarity and bipolar square wave, trapezoidal wave, semisinusoidal shape ripple, triangular wave.

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