CN202710113U

CN202710113U - Steady state alpha sensor

Info

Publication number: CN202710113U
Application number: CN 201220124995
Authority: CN
Inventors: 冯威; 陈杰; 冯娜
Original assignee: SHANDONG ZEYI AUTOMATIC CONTROL TECHNOLOGY CO LTD
Current assignee: SHANDONG ZEYI AUTOMATIC CONTROL TECHNOLOGY CO LTD
Priority date: 2012-03-29
Filing date: 2012-03-29
Publication date: 2013-01-30
Anticipated expiration: 2022-03-29

Abstract

The utility model relates to a measuring device for fluid flow in a pipeline, in particular to a steady state alpha sensor. The steady state alpha sensor comprises an alpha assembly and is characterized in that the front end of the alpha assembly is provided with a guiding area, a pre-drainage area and a compression area are respectively arranged behind the guiding area, the tail part of the compression area is provided with a wingtip, the inner side of the compression area is provided with a negative pressure split body, the alpha assembly is hollow in the axial direction, a negative pressure steady state area and an expansion negative pressure area are sequentially arranged in the alpha assembly, and the concentric angle of the compression area is opened at 45 degrees. The steady state alpha sensor has the advantages of simple structure, wide applicability, excellent low-range feature, wide range, seismic resistance, high temperature resistance, little loss of pressure, and the like.

Description

Stable state Alpha's sensor

Technical field

The utility model relates to a kind of measurement mechanism of pipeline inner fluid flow, specifically a kind of stable state Alpha's sensor.

Background technology

At present, differential pressure flowmeter is the most successful the most a kind of flow measurement mode that active procedure control and flow metering aspect are used.Differential pressure type flow meter all is based on Bernoulli's theorem, and such as flow nozzle, venturi and orifice plate all are to dam around the tube wall, and the fluid center pit flows through.The tapered element that dams that nearest American proposes, be suspended in the fluid line, fluid flows along tube wall after pipeline center's cone compression, the efflux coefficient that has overcome traditional differential pressure flowmeter is unstable, and is linear poor, and repeatability is not high, accuracy is not high, the easily easy fouling of contamination, range ratio is little, the problems such as on-the-spot installation requirement height.

Find through long-term experiment, although the degree of stability that element has improved the differential pressure measurement under the conventional fluidised form is greatly held back in American taper,, still have the low large problem of flow velocity discrete region degree deviation.To the present domestic large pipeline that has in a large number measurement demand, the measurement of low flow velocity requires to be difficult to satisfy, and particularly the large pipeline coal gas of iron and steel enterprise is measured, the high dust that exists in the flue air measuring of the large pipeline of Thermal Power Enterprises, high tar sticks, and it is more helpless that height adheres to medium.

Summary of the invention

The technical problems to be solved in the utility model is the higher problem of measurement lower limit that solves traditional differential pressure meter, redesign new taper and hold back element sampling below atmospheric pressure zone, it is simple in structure that this product is had, applicability is wide, the lower range characteristic good, broad quantum, antidetonation, high temperature resistant, the advantage such as crushing is little.

The concrete technical scheme that the utility model adopts is:

A kind of stable state Alpha's sensor, comprise Alpha's assembly, it is characterized in that, its front end has guiding area, be respectively equipped with pre-drainage district and compression zone after the guiding area, the compression zone afterbody is provided with wingtip, and the inboard, compression zone is provided with the negative pressure dividing body, the axial hollow of described Alpha's assembly is provided with negative pressure steady-state zone and expansion negative pressuren zone successively in it.

Further, concentric angle, described compression zone is that 45 degree open.

The utility model in use, Alpha's assembly hangs in the pipeline, the first differential pressure connecting pipe connecting tube inwall, the second differential pressure pressure guiding pipe is communicated with Alpha's assembly, in the rear end pressure of Alpha's assembly.

The utility model is owing to adopt the negative pressure taking of cutting apart with negative pressure dividing body, negative pressure expansion area, negative pressure steady-state zone to be installed with meter, be suspended in one-level mozzle and the accelerating tube and carry out flow measurement by differential pressure principle, contrast existing technology, the utility model is simple in structure, precision is high, good stability, good linearity, but negative pressure Measurement sensibility, applicability are wide, broad quantum, antidetonation, high temperature resistant, crushing is little, anti-stick dirt, be a kind of desirable flowmeter, be applicable to be installed in the pipeline of various different tube diameters, various media are carried out fluid measurement.

Through test, stable state Alpha sensor measurable lower limit that greatly extends under the same process condition, the positive and negative 2Pa of lower limit fluctuation stable state, whole instrument stability improves greatly.(specifically seeing Table 1)

Table 1 water droplet negative pressure retrofit testing tables of data

Description of drawings

Fig. 1 is structural representation of the present utility model;

Fig. 2 is that the utility model is at the structural representation of the state of use.

Among the figure, the 1-guiding area, the pre-drainage of 2-district, the 3-compression zone, the 4-wingtip, 5-negative pressure dividing body, 6-expands negative pressuren zone, 7-negative pressure steady-state zone, 8-inner-walls of duct, 9-Alpha assembly, 10-the first differential pressure connecting pipe, 11-the second differential pressure connecting pipe.

Embodiment

As shown in Figure 1, 2, a kind of stable state Alpha's sensor, comprise Alpha's assembly 9, its front end has guiding area 1, is respectively equipped with pre-drainage district 2 and compression zone 3 after the guiding area 1, and it is that 45 degree open that concentric angle is pressed in compression zone 3, its afterbody is provided with wingtip 4,3 inboards, compression zone are provided with negative pressure dividing body 5, and Alpha's assembly 9 axial hollows are provided with negative pressure steady-state zone 7 and expansion negative pressuren zone 6 successively in it.Alpha's assembly 9 hangs in the pipeline, and the first differential pressure connecting pipe 10 connecting tube inwalls 8, the second differential pressure pressure guiding pipes 11 are communicated with Alpha's assembly 9, in the 9 rear end pressures of Alpha's assembly.

The upstream and downstream of fluid before and after Alpha's assembly produces pressure differential Δ P.Alpha's assembly upstream pressure is PHA, and downstream pressure is PLB, and AB is sent to intelligent transducer by the differential pressure connecting pipe.

According to Bernoulli's theorem, differential pressure Δ P, flow are Q=K* ε * Δ P/ ρ+B (Q volumetric flow rates, density under the ρ fluid work condition state, ε is the expansion coefficient of medium, and K is instrument coefficient, and B is instrument skew) flow that like this can the ducted fluid of Measurement accuracy.Fixed flange is with fixing being connected with pipeline of whole instrument.

Characteristics of the present utility model are: after the compression of ducted flow through the compression zone, flow velocity is accelerated, can further accelerate after flowing through wingtip, by fluid mechanics knowledge inference, can greatly improve the differential pressure Δ P of Alpha's assembly front and back, but simultaneously, the negative pressure of wingtip rear region, can produce larger fluctuation, this fluctuation has limited the measurement lower limit performance of instrument greatly.Alpha's assembly negative pressuren zone structure designs separately, is divided into negative pressure dividing body, negative pressure expansion area, 3 parts of negative pressure steady-state zone, and the measurement lower limit performance of the instrument that greatly improves has been guaranteed the application that good low flow rates of fluid is measured.

When the utility model uses, according to hydromechanical mean flow rate point algorithm in the pipeline, whole instrument can be placed pipeline center's point, through the analysis of top measurement data, low fluid-velocity survey performance is better than like product greatly.The utility model is simple in structure, and precision is high, good stability, and good linearity, negative pressure Measurement sensibility, applicability are wide, broad quantum, antidetonation, high temperature resistant, crushing is little, anti-stick dirt is a kind of desirable flowmeter, is applicable to be installed in the pipeline of various different tube diameters, and various media are carried out fluid measurement.

Claims

1. stable state Alpha sensor, comprise Alpha's assembly, it is characterized in that, its front end has guiding area, be respectively equipped with pre-drainage district and compression zone after the guiding area, the compression zone afterbody is provided with wingtip, and the inboard, compression zone is provided with the negative pressure dividing body, the axial hollow of described Alpha's assembly is provided with negative pressure steady-state zone and expansion negative pressuren zone successively in it.

2. stable state Alpha's sensor according to claim 1 is characterized in that, concentric angle, described compression zone is that 45 degree open.

3. stable state Alpha's sensor according to claim 1 and 2 is characterized in that, Alpha's assembly hangs in the pipeline, the first differential pressure connecting pipe connecting tube inwall, and the second differential pressure pressure guiding pipe is communicated with Alpha's assembly, in the rear end pressure of Alpha's assembly.