CN108871478A - A kind of ultrasonic flowmeter - Google Patents

Abstract

The present invention provides a kind of ultrasonic flowmeters, include shell, and the shell is in direct piping structure, and the direct piping structure of shell is equipped with input end and outlet end；Several ultrasonic transducer groups, environmental sensor unit and control unit are equipped on shell, the ultrasonic transducer group, environmentally sensitive unit and control unit are electrically connected；The shell is equipped with flange arrangement in the input end of direct piping and/or outlet end；The direct piping structure is equipped with gas rectifier structure by input end side；The gas rectifier structure includes the airflow channel that cross section is in honeycomb structure, and airflow channel is axial whole parallel with direct piping.The beneficial effects of the present invention are：On the one hand it can be applicable in shorter direct piping, reduce the occupancy volume of gas flowmeter runner, on the other hand but also ultrasonic measurement is more stable accurate.

Description

An Ultrasonic Flowmeter

technical field

The invention relates to the technical field of gas metering devices, in particular to a gas flow meter.

Background technique

The basic principle of the existing reflective ultrasonic gas flowmeter is the time difference method. The ultrasonic sensor installed on the flow channel wall and the direction of the gas flow at a certain angle measures the ultrasonic signal. The forward flow time and reverse flow time propagated between the ultrasonic sensors, The airflow velocity information V(Δt) can be obtained by the difference Δt between the forward flow time and the reverse flow time, but the applicant found through research that due to the turbulence of the airflow in the gas flowmeter, the forward flow time measured by the ultrasonic sensor and There is a certain error or fluctuation in the difference of the reverse flow time, which in turn affects the overall measurement accuracy of the gas flow.

Contents of the invention

Aiming at the deficiencies in the prior art, the present invention provides an ultrasonic flowmeter, the purpose of which is to realize flow measurement with higher precision.

To achieve the above object, the present invention adopts the following technical solutions:

An ultrasonic flowmeter, comprising a shell, the shell is a straight-through pipe structure, the straight-through pipe structure of the shell is provided with an inlet end and an outlet end; the shell is provided with several ultrasonic transducer groups, environmental sensor units and The control unit, the ultrasonic transducer group, the environmental sensing unit and the control unit are electrically connected; the shell is provided with a flange structure at the inlet end and/or outlet end of the straight-through pipe; the straight-through pipe structure is close to the inlet A gas rectification structure is provided on one side of the end; the gas rectification structure includes an air flow channel with a honeycomb structure in cross section, and the air flow channel is parallel to the axial direction of the straight-through pipe as a whole.

Further, the inlet end of the straight-through pipeline structure is provided with a diversion ring, the diversion ring is generally tapered or trumpet-shaped, and the inner wall of the longitudinal section of the diversion ring is streamlined.

The front end of the flow channel is equipped with a guide ring and a gas rectification structure, so that the anisotropic chaotic flow at the front end of the flow channel is rectified into an effective flow parallel to the axial direction of the flow channel, which can rectify the fluid with a larger Reynolds number at the front end, and the gas rectification The laminar flow wake at the rear end of the structure is small, and it is easier to eliminate it in a shorter straight pipe section. On the one hand, it can be applied to a shorter straight pipe, reducing the occupied volume of the flow channel of the gas flowmeter, and on the other hand, it can solve the measurement caused by gas disturbance. The accuracy error also makes the ultrasonic measurement more stable and accurate.

Description of drawings

Fig. 1 is a structural axonometric schematic diagram of the embodiment.

Fig. 2 is a schematic rear view of the embodiment.

Fig. 3 is a schematic cross-sectional view of the embodiment.

Detailed ways

The technical solutions in the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

A kind of ultrasonic flow meter, as shown in Figure 1, comprises housing 1, and described housing 1 is straight-through pipeline structure, and the straight-through pipeline structure of housing is provided with inlet end and outlet end; Both inlet end and outlet end are provided with Flange structure 2 for easy installation and connection; said housing 1 is provided with an installation base 5, said installation base 5 is vertical to the straight pipe structure as a whole, said installation base is provided with a control box 6, and the control box 6 is connected to The installation base 5 is connected by rotation; on the housing 1, several ultrasonic transducer groups, environmental sensor units and control units are arranged, and the ultrasonic transducer groups, environmental sensor units and control units are electrically connected; The pipeline structure is provided with a gas rectification structure 3 on the side near the inlet end; the gas rectification structure includes an airflow channel with a honeycomb structure in cross section, and the airflow channel is parallel to the axial direction of the straight-through pipeline; the inlet end of the straight-through pipeline structure is provided with Guide ring 4, the overall shape of the guide ring 4 is conical or trumpet-shaped, and the inner wall of the longitudinal section of the guide ring 4 is streamlined, which can effectively reduce the pressure loss of the gas when the caliber becomes smaller, and keep the fluid constant Flow state; the caliber of the guide ring 4 on the side close to the gas rectification structure 3 is slightly smaller than the outer edge of the gas rectification structure 3 to prevent the gas rectification structure 3 from protruding; the side of the straight-through pipeline 1 near the inlet end is provided with a gas rectification structure 3 ; The gas rectifying structure 3 comprises a cross-section of the airflow channel in a honeycomb structure, and the airflow channel is parallel to the axial direction of the straight-through pipeline; , triangular one or more, so that the gas rectification structure 3 adapts to the shape design of the inner cross-section of different straight-through pipes 1; the outer edge of the gas rectification structure 3 is connected with the inner diameter of the straight-through pipe by interference fit, thus The gas rectification structure 3 matched with the flow channel structure design of the existing gas flowmeter is installed to improve the turbulence effect of the existing gas flowmeter.

A temperature and pressure sensor is installed on the side wall of the flow channel, and the flow rate of the flowmeter can be corrected by temperature and pressure through the collected temperature and pressure data.

The casing is made of cast iron, which can carry the measurement of medium and high pressure gas (1.6MPa). As shown in Figure 2, the casing has a pressure taking hole 3 and a temperature measuring hole 2, which is convenient for the flowmeter to be tested and inspected. Measure the internal pressure and temperature of the flowmeter.

The gas rectification structure 3 satisfies L≥10D _H ; where L is the length of the gas rectification structure 3, and D _H is the hydraulic diameter of the honeycomb cell in the honeycomb structure of the air flow channel, and is the characteristic length of the non-circular pipe flow; thus effectively The turbulent airflow is rectified into a smooth straight-through airflow; the hydraulic diameter of the honeycomb unit=4A/P, where A is the flow area of the honeycomb unit, and P is the wetted periphery of the honeycomb unit; the gas rectification structure Need to meet: d≥50a, where d is the diameter of the inscribed circle of the honeycomb cell in the honeycomb structure of the airflow channel, and a is the wall thickness of the side wall of the honeycomb cell. Based on this design, the honeycomb cell in the airflow channel Not only the thickness of the side wall is small, but also the throttling effect on the pipeline is small, and the pressure loss is small; the diameter d of the inscribed circle of the honeycomb unit in the honeycomb structure described in the air flow channel satisfies 0.077D≤d≤0.173D, where D is the flow channel The diameter of the tube can achieve better rectification effect and eliminate the influence of the wall thickness of the honeycomb cell on the flow field at the outlet of the rectifier.

In summary, through the design of the guide ring 4 and the gas rectification structure 3, the anisotropic chaotic flow at the front end of the flow channel is rectified into an effective flow parallel to the axial direction of the flow channel, and the fluid with a larger Reynolds number at the front end can be rectified , and the rectification effect is good. The laminar flow wake at the rear end of the rectifier is small, which is easier to eliminate in the shorter straight pipe section, and the straight pipe section at the rear end of the rectifier requires less.

The number of the ultrasonic transducer groups is 2 groups, and the projection angle of the two groups of ultrasonic transducer groups on the flow channel cross section is between 30° and 90°. Any ultrasonic transducer group includes two ultrasonic transducers installed on the straight-through pipeline in a V-shaped angle, and the angle θ of the V-shaped angle is between 30° and 90°, so that the volume of the flowmeter can be reduced. In this case, the effective sound path is increased. The ultrasonic transducer is an ultrasonic transducer that integrates ultrasonic emission and ultrasonic reception; several modified energy-gathering reflective surface structures 5 are also provided on the inner wall of the straight-through pipeline 1; any modified energy-gathering reflective surface structure 5 is elliptical The curved surface shape, the concave surface of the curved surface shape is in the inflection point area of the V-shaped path of ultrasonic transmission and reception in the ultrasonic transducer group; this design can effectively suppress the deflection of the high-velocity ultrasonic main beam and the Kepler effect, effectively The range ratio of the measuring instrument is greatly expanded; after the signal sent by the ultrasonic transducer at the transmitting end is focused and reflected by the modified energy-gathering reflective surface structure, the strength of the received and transmitted ultrasonic signal is enhanced, the offset of the ultrasonic signal is corrected, and the flow rate is increased. The measurement range realizes the effective reception of the ultrasonic signal by the ultrasonic transducer at the receiving end.

The projection of the two sets of ultrasonic transducers on the cross-section of the flow channel or the included angle of the plane where the signal transmitting-receiving transmission path is located is between 30° and 90°. The measurement of multiple sets of ultrasonic transducer groups can obtain relatively more comprehensive and complete sensing data, thereby providing data support for optimizing the flow calculation through the flow channel through the algorithm, and greatly reducing the measurement error caused by a single pair of sensors.

As shown in Figure 3, a control box base 5 is provided on the housing 8, and the signal lead-out line inside the flowmeter is passed through and sealed with glue by the line sealing plug 7, and the line sealing plug 7 is pressed by the sealing plug 6 is fixed on the step hole on the upper part of the shell, the main control board group 3 is fixed inside the control box by screws, and is sealed by the control box cover 2 and the control box sealing ring 10, and the control box cover 2 is also equipped with a transparent The cover surface 1, the LCD and other display units provided on the main control board group 3 are opposite to the transparent cover surface 1; a lithium battery 4 is provided on the lower side of the main control board group 3 to provide electricity for electronic components; One side is provided with anti-rotation pin 15, which is used to limit the rotation of the control box base to exceed the set angle or exceed 350°, and the flow channel assembly 17 is also provided with positioning mounting holes, so that the control box part is convenient to connect with it through the positioning pin 16 Installation; in Figure 3, other components also include the runner group sealing ring 9, the battery cover sealing ring 12, the first O-ring 13, and the second O-ring 14 to achieve a sealed assembly, and also include the battery compartment and the battery cover 11, in order to facilitate the assembly of the power consumption battery. Through the rotary connection between the control box and the installation base, and the axial angle installation between the transparent cover 1 and the installation base, it is convenient to view the data information of the flowmeter. The axial angle range between the transparent cover 1 and the installation base is 30° -60°, the preferred angle is 50°.

Finally, it is noted that the above embodiments are only used to illustrate the technical solution of the present invention without limitation. Those of ordinary skill in the art should understand that the technical solution of the present invention can be modified or equivalently replaced without departing from the technical solution of the present invention. The purpose and scope should be included in the scope of the claims of the present invention.

Claims (10)

1. a kind of ultrasonic flowmeter includes shell, the shell is in direct piping structure, and the direct piping structure of shell is equipped with Input end and outlet end；It is single that several ultrasonic transducer groups, environmental sensor unit, display unit and control are equipped on shell Member, the ultrasonic transducer group, environmentally sensitive unit, display unit and control unit are electrically connected；It is characterized in that：It is described Shell is equipped with flange arrangement in the input end of direct piping and/or outlet end；The direct piping structure is set by input end side There is gas rectifier structure；The gas rectifier structure includes the airflow channel that cross section is in honeycomb structure, airflow channel and straight It threads a pipe axial whole parallel.

2. a kind of ultrasonic flowmeter as described in claim 1, it is characterised in that：The input end of the direct piping structure is set There is a guide ring, the guide ring is integrally conical or tubaeform, and the longitudinal section inner wall of guide ring is streamlined.

3. a kind of ultrasonic flowmeter as claimed in claim 2, it is characterised in that：The gas rectifier structure meet L >= 10D_H；Wherein L is gas rectifier structure length, D_HFor the hydraulic diameter of cellular unit lattice in honeycomb structure described in airflow channel, It and is the characteristic length of non-pipe flow；The hydraulic diameter D of the cellular unit lattice_H=4A/P, wherein A is cellular unit lattice Area of passage, P are the wetted perimeter of cellular unit lattice.

4. a kind of ultrasonic flowmeter as described in any one of claims 1 to 3, it is characterised in that：The gas rectifier structure Meet：D >=50a, wherein d is the inscribed circle diameter of cellular unit lattice in honeycomb structure described in airflow channel, and a is honeycomb list The wall thickness of first lattice side wall；In honeycomb structure described in airflow channel the inscribed circle diameter d of cellular unit lattice meet 0.077D≤d≤ 0.173D, wherein D is runner caliber.

5. a kind of ultrasonic flowmeter as described in claim 1, it is characterised in that：The outer rim of the gas rectifier structure and straight The internal diameter threaded a pipe is interference fit connection.

6. a kind of ultrasonic flowmeter as described in claim 1, it is characterised in that：The quantity of the ultrasonic transducer group is not Less than 2, and any ultrasonic transducer group includes two ultrasonic transducers；The ultrasonic transducer is ultrasonic wave transmitting- Ultrasonic wave receives the ultrasonic transducer being integrated；Two V-shaped folders of ultrasonic transducer in any ultrasonic transducer group Angle is installed on direct piping, and the angle of V-arrangement angle is at 40 °~90 °.

7. a kind of ultrasonic flowmeter as claimed in claim 6, it is characterised in that：It is additionally provided in the inner wall of direct piping several Amendment type cumulative reflecting surface structure；Any amendment type cumulative reflecting surface structure is in arc shape, the concave surface of the arc shape In ultrasonic transducer group ultrasonic wave transmitting receive V-shaped path knee region.

8. a kind of ultrasonic flowmeter as described in claim 1, it is characterised in that：The environmentally sensitive unit is passed comprising pressure Feel unit and/or temperature sensing unit.

9. a kind of ultrasonic flowmeter as described in claim 1, it is characterised in that：The shell is equipped with mounting seat, institute Mounting seat entirety and direct piping structure vertical are stated, the mounting seat is equipped with control box, and controls box and mounting seat For rotation connection.

10. a kind of ultrasonic flowmeter as claimed in claim 9, it is characterised in that：The display unit is mounted on control box Interior, corresponding, control box is equipped with and the matched transparent capping of display unit, the axial angle range of transparent capping and mounting seat It is 30 ° -60 °.