CN2699248Y - Oil-water double phase flow measuring apparatus based on standard Venturi tube and turbine flow meter - Google Patents

Abstract

The utility model relates to an oil-water double phase flow measuring apparatus based on a standard venturi pipe and a turbine flow meter, comprising a metering pipeline, a flow mixer which is arranged at the front end of the metering pipeline, a turbine flow meter with high viscosity and a temperature sensor which are arranged at the rear end of the metering pipeline, a standard venturi pipe which is arranged at the middle portion of the metering pipeline, a differential pressure transducer which is connected with the venturi pipe, an A/D transition card and a computer. Each sensor is connected with the computer by the A/D transition card in a clamping way. The utility model has the advantages of small size, simple structure, convenient installation, low pressing loss, wide scope of application, a plurality of metering parameters which can be obtained, high flow capacity checking precision, etc., and is suitable for metering oil-liquid two-phase flow of chemical industry solvent extraction, etc.

Description

Oil-water two-phase flow measurement mechanism based on standard Venturi tube and turbo flow meter

Technical field

The utility model relates to a kind of oil-water two-phase flow measurement mechanism based on standard Venturi tube and turbo flow meter.

Background technology

Oil-water two-phase flow is prevalent in the petroleum industry.The complicacy of oil-water two-phase flow system brings a lot of difficulties for the measurement of flow and density.Current measuring methods mainly is to carry out profit two earlier to be separated, and measures single-phase flow then respectively.But because oil-water separation is subjected to influence of various factors easily, profit two-phase separating difficulty is bigger, and separating effect is bad, thereby causes measuring accuracy not high; And because profit two is separated and needs the regular hour, when flow was very big, two are separated need be chronic, makes that the metering time of profit two-phase is elongated, is unfavorable for that the real-time of measurement parameter detects.

Another kind of metering method commonly used is oil-water two-phase flow to be mixed become homogeneous flow, utilizes single-phase flowmeter such as restriction flowmeter, volumeter to wait and obtains flow.But the flow that obtains is a profit two-phase total volumetric flow rate, can't obtain each minute phase content and separate phase flow rate data.Though densitometer can solve the individual phase measurement problem in conjunction with single-phase flowmeter, measuring accuracy is not ideal enough during still actual the use, and cost is also very high.Vibrating tube densimeter commonly used is very responsive to field conditions such as the temperature of medium, pressure.And there is safety problem in gamma ray density meter, operating conditions is required high.Also can still there be shortcomings such as cost height, service condition harshness, installation and maintenance inconvenience in the coriolis mass flowmeters of Chu Xianing with solving profit individual phase measurement problem in recent years.

Summary of the invention

The purpose of this utility model provides a kind of profit two-phase measurement mechanism based on standard Venturi tube and turbo flow meter.

It has the metering pipeline, on the metering pipeline, be provided with mixed flow device, standard Venturi tube, wide viscosity type turbo flow meter, temperature sensor successively, the supporting differential pressure pick-up that is equipped with of standard Venturi tube, wide viscosity type turbo flow meter, differential pressure pick-up, temperature sensor link to each other with the A/D transition card, and the A/D transition card links to each other with computing machine.

Advantage of the present utility model is as follows:

1) do not carrying out under the situation that profit two is separated, utilizing Venturi tube and turbo flow meter the branch phase content and the flow of test fluid density and profit two-phase simultaneously, improving precision and real-time that the oil-water two-phase flow amount detects.

2) selected turbine flow is counted wide viscosity type turbo flow meter, it is the measuring accuracy height not only, easy for installation, be difficult for stopping up, be suitable for high-tension measurement, can be used for various bores, especially small-bore, and compare with the flowmeter that positive displacement etc. can be used for the profit two-phase flow measurement, it is little that turbo flow meter has a volume, easy for installation, advantage such as flow range is bigger.In addition, wide viscosity type turbo flow meter is owing to the viscosity compensation is arranged, so be particularly suitable for the measurement of high viscosity fluid flows such as profit two-phase.

3) the utility model can be used for the measurement of the oil-water two-phase flow system in the petroleum industry, and with respect to existing multiple measuring method, characteristics of the present utility model are to solve the engineering survey problem with the ingenious combination of traditional single-phase flow measurement instrument.Use the combination of Venturi tube and turbo flow meter and measure oil-water two-phase flow total volumetric flow rate, hybrid density, branch phase content, phase-splitting volumetric flow rate and phase-splitting mass rate simultaneously.Measurement is reliable, stable, precision is high, applied widely, easy for installation, volume is little.

Description of drawings

Accompanying drawing is based on the oil-water two-phase flow measurement mechanism structural representation of standard Venturi tube and turbo flow meter.

Embodiment

Restricting element selection standard Venturi tube in the utility model.After oil-water two-phase flow to be measured entered metering pipeline 1, by mixed flow device 2, oil-water two-phase flow is mixed became homogeneous flow earlier.Differential pressure pick-up 5 and the 3 supporting installations of standard Venturi tube.Differential pressure signal changes the standard electric signal into sends into computing machine 8 through A/D transition card 7.Turbo flow meter 4 obtains the profit total volumetric flow rate of whole pipeline and changes flow signal into the standard electric signal sends into computing machine 8 through A/D transition card 7.Temperature sensor 6 is used for detecting the oil-water two-phase flow temperature T and changes temperature signal into the standard electric signal sends into computing machine 8 through A/D transition card 7.In computing machine 8, be provided with memory module, store density and the data such as coefficient of flow of restricting element, perforated area of profit two-phase under different temperatures.Computing machine 8 is handled in real time, obtains the oil-water two-phase flow hybrid density, divides phase content and separate phase flow rate.

Realization profit two-phase measuring method for measuring is undertaken by following concrete steps:

(1) utilize turbo flow meter to obtain the profit two-phase total volumetric flow rate q of pipeline _v, computing formula is as follows:

q _v＝ξf (1)

In the formula:

ξ is the coefficient of flow of turbo flow meter.Generally speaking, in specified flow range and in certain liquid viscosity scope, ξ and fluid viscosity are irrelevant, are constants.Because the viscosity of profit two-phase mixture is very high, so turbo flow meter is selected wide viscosity type turbo flow meter for use, to eliminate the influence of viscosity.F is the pulse output number of turbo flow meter.q _vBe the oil-water two-phase flow total volumetric flow rate.

(2) the utility model adopts the standard knot fluid element, and measuring principle satisfies shellfish and makes great efforts equation and continuity equation, therefore according to Throttle Principle:

$q_v=\mathrm{\α}{A}_0\sqrt{\frac{2\mathrm{\Δp}}{\mathrm{\ρ}}}---\left(2\right)$

It is as follows to obtain profit two-phase hybrid density ρ computing formula:

$\mathrm{\ρ}=\frac{2{\mathrm{\α}}^2{A}_0^2\mathrm{\Δp}}{q_v^2}---\left(3\right)$

In the formula:

q _vObtained by turbo flow meter, the differential pressure Δ p of restricting element place sampling pipe is obtained by differential pressure pick-up.α is a standard Venturi tube coefficient of flow, when fluid Reynolds number during greater than critical Reynolds number, is a constant, and concrete numerical value is by experimental calibration.A ₀Be the restricting element perforated area.ρ is the oil-water two-phase flow hybrid density of restricting element of flowing through.

(3) owing to the oil-water two-phase flow hybrid density be:

ρ＝x ₁ρ ₁+(1-x ₁)ρ ₂ (4)

Obtaining the profit two-phase by formula (4) divides phase content and separate phase flow rate computing formula as follows:

The rate that contains of oil is $x_1=\frac{\mathrm{\ρ}-{\mathrm{\ρ}}_2}{{\mathrm{\ρ}}_1-{\mathrm{\ρ}}_2}$

The rate that contains of water is x ₂=1-x ₁

The volumetric flow rate of oil is q _V1msm=x ₁q _v

The volumetric flow rate of water is q _V2msm=x ₂q _v

The mass rate of oil is q _M1=ρ ₁q _V1msm

The mass rate of water is q _M2=ρ ₂q _V2msm

In the formula:

ρ ₁, ρ ₂Be respectively the density of temperature be T time oil and water.Temperature T is obtained by temperature sensor.x ₁, x ₂Be respectively the rate that contains of oil and water.q _V1msm, q _V2msmBe respectively the volumetric flow rate of oil and water.q _M1, q _M2Be respectively the mass rate of oil and water.

Claims (3)

1. profit two-phase measurement mechanism based on standard Venturi tube and turbo flow meter, it is characterized in that it has metering pipeline (1), on metering pipeline (1), be provided with mixed flow device (2), standard Venturi tube (3), turbo flow meter (4), temperature sensor (6) successively, the supporting differential pressure pick-up (5) that is equipped with of standard Venturi tube (3), differential pressure pick-up (5), temperature sensor (6), turbo flow meter (4) link to each other with A/D transition card (7), and A/D transition card (7) links to each other with computing machine (8).

2. the described a kind of oil-water two-phase flow measurement mechanism based on standard Venturi tube and turbo flow meter of claim 1 is characterized in that said turbo flow meter adopts wide viscosity type turbo flow meter.

3. the described a kind of oil-water two-phase flow measurement mechanism based on standard Venturi tube and turbo flow meter of claim 1 is characterized in that said mixed flow device adopts single helical-ribbon type oar or two helical-ribbon type oar liquid liquid phase stirrer.