CN101403406A - Plunger type flow pulsation generator - Google Patents

Abstract

The invention discloses a plunger type flow pulsation generator, comprising a turntable with a positioning hole, a propulsion shaft, a propulsion linear guide rail group, a guiding linear guide rail group, a plunger, a cylinder barrel, a sealing end cover, a motor, a reducer and a frequency conversion devices etc. The motor drives the turntable to rotate, and the propulsion shaft fixed on the turntable and the propulsion linear guide group convert the circular motion into the reciprocating linear simple harmonic motion of the plunger in the cylinder. The plunger cylinder is connected to the flow pipeline through the tee, and a certain amount of main pipeline fluid is sucked into or pressed out of the cylinder, and a sinusoidal pulse is superimposed on the main flow. The cycle of the pulsation can be adjusted by changing the speed of the stepping motor by the frequency converter. Adjust the rotation radius of the propulsion shaft fixed on the turntable to change the stroke of the plunger. In addition, the plunger kits with different diameters can also be replaced. The above two methods are combined to change the suction capacity of the plunger cylinder to obtain different widths. value pulsation. This plunger type flow pulsation generator can produce standard sinusoidal flow output with different precise pulsation amplitudes and continuous change periods.

Description

Plunger Flow Pulse Generator

technical field

The invention relates to the field of flow control in pipelines, in particular to a plunger-type flow pulsation generator for generating pulsating flow in pipelines with adjustable amplitude and period.

Background technique

There are a large number of two-phase flow instabilities in nuclear reactors and boiler power plants, one of which is flow pulsation. In addition, the contraction of the human heart also produces rhythmic fluctuations in blood flow in the arteries. In order to analyze the effects of two-phase flow instabilities in industry and to simulate heart pumping in medical research, it is necessary to generate pulsating flow in experimental piping. The conventional flow pulsation generation method is generally to add an auxiliary pump controlled by a frequency converter after the main pump in the pipeline. When the speed of the main pump is constant, the frequency converter is used to change the speed of the auxiliary pump, so that the pulsating flow is superimposed on the main flow. This kind of pulsation generation method is easy to experiment and operate: but the flow pulsation amplitude obtained is limited, generally not exceeding 30% of the average flow; the pulsation curve is not regular enough; the pulsation amplitude is not easy to change; The influence of the change of the auxiliary pump speed can not produce high-frequency pulsation; and it has a great impact on the service life of the auxiliary pump.

US patents US4512514 and US4267856 describe two passive flow pulsation generating devices. At a fixed flow rate, the pulsation amplitude and frequency generated by the two flow pulsation generating devices cannot be adjusted.

Japanese patent 2002-257032 describes a DC motor driven piston type pulse pump. The front end of the piston cylinder is respectively connected with the inlet and outlet pipes by the inlet and outlet valves, and the eccentric wheel drives the piston to reciprocate in the piston cylinder to generate intermittent pulsating flow. The frequency of the pulsation can be adjusted by changing the motor speed. However, the diameter of the piston cylinder and the stroke of the piston are fixed, so the amplitude of the pulsation is fixed. In addition, since the inlet and outlet pipes are respectively controlled by the inlet and outlet valves, when the fluid is sucked in, the outlet valve will be closed and there will be no flow downstream. Therefore, the pulsating pump produces intermittent pulsating flow.

Contents of the invention

The purpose of the present invention is to overcome above-mentioned deficiency of prior art, a kind of plunger type flow pulsation generator that can adjust pulsation amplitude and pulsation period is provided, and this generator makes the instantaneous flow curve in pipeline be the sinusoidal curve of fluctuation, and The amplitude and period of the flow pulsation can be adjusted conveniently, so that the flow fluctuation in the pipeline with controllable pulsation amplitude and period can be obtained.

The invention utilizes the combination of the bearing and the slider to decompose the circular motion of the propulsion shaft rotating with the turntable into the rotation of the bearing, the up and down sliding of the propulsion slider on the propulsion guide rail, and the reciprocating linear simple harmonic motion of the plunger driven by the propulsion guide rail in the cylinder ; Connect the outlet of the cylinder to the flow pipe, use the reciprocating linear simple harmonic motion of the plunger in the cylinder to suck or discharge the fluid into the cylinder, and superimpose a pulsation on the main flow of the pipe; change the motor speed to adjust the flow pulsation through the frequency converter Period; change the fixed radius of the propulsion shaft on the turntable to change the stroke of the plunger, or replace the cylinder assembly with different plunger diameters, thereby changing the suction volume in the cylinder within each fixed pulsation period (equal to the total discharge amount), to change the amplitude of the pulsation.

In order to achieve the above object, the present invention adopts following technical scheme:

The guide linear guide rail of the present invention is fixed on the side wall of the base, guide sliders are respectively arranged on the two guide linear guide rails, the base of the push guide rail and the guide slider are fixed together, the front end of the base of the push guide rail is connected with the end of the plunger, and the front end of the plunger Connect the cylinder and the sealing end cover, the cylinder and the sealing end cover are fixed on the front wall of the base, the advancing linear guide rail is fixed on the guide rail base surface of the advancing guide rail base, and the advancing slider on the advancing linear guide rail is connected with the bearing groove One end of the propulsion shaft is connected to the slider base through the bearing in the bearing groove, and the other end is connected to the positioning holes on the different radii of the turntable, and the turntable is connected to the handle with the sleeve. The motor-driven reducer output shaft is connected to the shaft sleeve of the handle.

The positioning holes are hexagonal holes distributed at different radii in the circumference of the turntable. The end connecting the propulsion shaft and the turntable is a hexagonal column of the same size. The propulsion shaft is fixed at the positioning holes in different radial directions of the turntable to produce different plunger strokes.

The end cover of the cylinder barrel adopts the Ster seal sealing plunger, the end cover of the cylinder barrel and the cylinder barrel are fixed on the front end of the base by bolts, and the end of the plunger is connected with the base of the vertical guide rail by thread.

The invention continuously sucks and discharges the fluid in the main pipe through the simple harmonic motion of the plunger in the cylinder, and superimposes a sinusoidal pulsating flow on the average main flow. The period and amplitude of the sinusoidal pulsation can be adjusted by actively and precisely changing the suction frequency and volume, so that sinusoidal flow fluctuations with different pulsation periods and pulsation amplitudes under each average main flow can be obtained.

Description of drawings

Fig. 1 (a) is the isometric view of the flow pulsation generator of the present invention;

Figure 1(b) is a front view of the flow pulsation generator, which does not include the reducer and the motor;

Figure 1(c) is the left view of the flow pulsation generator, which does not include the reducer and the motor;

Figure 1(d) is a top view of the flow pulsation generator, which does not include the reducer and the motor;

Fig. 2 is an assembly drawing of the plunger cylinder assembly;

Figure 3 is an axial view of the assembly of each guide rail assembly;

Fig. 4 is a schematic diagram of velocity decomposition of a flow pulsation generator;

The content of the present invention will be described in further detail below in conjunction with the accompanying drawings.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

Referring to Fig. 1(a), Fig. 1(b), Fig. 1(c) and Fig. 1(d), the guiding linear guide rails 7, 14 are fixed on the side wall of the base 1 . The guide rail base 9 is fixed together with the guide sliders 8,13 on the guide linear guide rails 7,14 by screws. The front end of the propulsion guide rail base 9 is connected with the end of the plunger 4 . The cylinder barrel 2 and the sealing end cover 3 matched at the front end of the plunger 4 are fixed on the front end of the base 1 . The propulsion linear guide rail 10 is fixed on the guide rail base surface of the propulsion guide rail base 9 . The propelling slide block 11 on the propelling linear guide rail 10 is connected with the slide block base 12 with the bearing groove. One end of the propulsion shaft 15 is connected with the propulsion shaft 15 through the bearing 19 in the bearing groove, and the other end is inserted in the positioning holes 17 on different radii of the rotating disk 16, and is fixed on the rotating disk 16 by a nut. The rotating disk 16 is connected to the handle 18 with the axle sleeve by screws and positioning pins. The output shaft of the reducer 5 driven by the motor 6 is connected to the shaft sleeve of the handle 18 to drive the turntable 16 to rotate.

Referring to Fig. 2, the cylinder 2 is a stainless steel cylinder with a flange, and the front end of the cylinder 2 is an outlet pipe section. After the rear end of the cylinder 2 is inserted into the sealing end cover 3, the cylinder 2 and the sealing end cover 3 are fixed on the front end of the base 1 by screws, and the flanges of the two are sealed by an O-ring 20 . The sealing end cover 3 is a flange structure with holes. In the guide hole of the plunger 4 of the sealing end cap 3, a grid ring 21, a step seal 22 and a dustproof ring 23 are arranged in sequence to guide, seal and prevent the plunger 4 from dust. The movable end of the plunger 4 in the cylinder 2 is a plunger rod matched with the cylinder 2 . The other end is a bolt structure 24, which is connected with the bolt holes reserved for the vertical guide rail base 9. The entire plunger cylinder assembly can be easily removed from the base 1 for maintenance or replacement of cylinder assemblies with different plunger rod diameters.

Referring to Fig. 3, the propulsion linear guide 10, the propulsion slider 11, the guide linear guides 7, 14 and the upper sliders 8, 13 are standard four-row bead self-lubricating linear slide assemblies. Under the condition of tension and pressure in the direction of the base surface of the guide rail, the slider can move linearly along the axial direction of the linear guide rail. The guiding linear guide rails 7, 14 are fixed in the horizontal direction of the side wall of the base 1, and guide the horizontal movement of the vertical guide rail base 9 and the plunger 4. Propel guide rail base 9 sides respectively have a slide block connection base surface up and down, and advance guide rail base 9 is connected on the slide block 8,13 that guides linear guide rail 7,14 by screw. The front side of the propulsion guide rail base 9 is the fixed base surface of the propulsion linear guide rail 10, and the propulsion linear guide rail 10 is fixed on the base surface of the propulsion guide rail base 9 by screws. The other side of the propulsion guide rail base 9 is a bolt hole matching with the bolt 24 at the end of the plunger 4 and connected with the plunger 4 . The propelling slider 11 on the propelling guide rail 10 is connected with a slider base 12 with a bearing groove. One end of the propulsion shaft 15 is a bearing rod, the middle section is a hexagonal column matched with the hexagonal positioning hole 17 on the rotating disk 16, and the end is a bolt rod. The bearing rod section of the propulsion shaft 15 is connected to the slider base 12 via a bearing 19 .

The specific assembly of the turntable and the handle is shown in Fig. 1(b): the turntable 16 is a disc with a positioning hole 17. The positioning hole 17 is a hexagonal hole matching the hexagonal column of the propulsion shaft 15, and is distributed at different radii of the turntable 16 along the circumferential direction. After the propulsion shaft 15 connected with the slider base 12 is inserted into the positioning hole 17 at a certain radius, it is fixed on the turntable 16 by a nut, and moves in a circle with the turntable 16 . Handle 18 is that the center has the U-shaped steel plate that matches axle sleeve with reducer 5 output shafts. The two ends of the handle 18 are fixed to the outermost screw and the positioning pin holes of the rotating disk 16 by screws and positioning pins.

1 (a) specifically describe the operation of the pulse generator: the output shaft of the reducer 5 driven by the motor 6 is connected to the shaft sleeve of the handle 18, and the turntable 16 is driven to rotate by the handle 18. The propulsion shaft 15 can move circularly with the turntable 16 on the radius of each positioning hole 17 . The bearing 19 and the slider 11 decompose the circular motion of the propulsion shaft 15 into the rotation of the bearing 19, the up and down sliding of the propulsion slider 11 on the propulsion guide rail 10 and the reciprocating linear simple harmonic motion of the plunger 4 driven by the propulsion guide rail 10 .

The movement of the plunger 4 can be analyzed with reference to the speed decomposition schematic diagram in Figure 4: the radius of the uniform circular motion of the propulsion slider 11 along with the propulsion shaft 15 is the radius r of the positioning hole 17 on the turntable 16, and the rotation frequency is that the motor 6 passes through the reducer 5. The frequency f of driving the turntable 16 to rotate. _o The propulsion slider 11 slides up and down on the propulsion guide rail 10, and at the same time drives the propulsion guide rail 10 to perform linear reciprocating motion in the horizontal direction. This horizontal reciprocating motion is the decomposition of the uniform circular motion of the pushing slider 11 in the horizontal direction, and its horizontal instantaneous speed u ₁ =2πrf·sin (2πft) is a standard sinusoidal curve. Therefore, the plunger 4 connected to the front end of the propelling rail 10 sucks and pushes the liquid in the cylinder 2 to form a flow pulsation curve at the outlet of the cylinder 2, which is also a standard sinusoidal curve. The cycle of flow pulsation is determined by the motor 6 speed. The amplitude of the pulsation can be adjusted by changing the positioning radius of the propulsion shaft 15 to change the stroke of the plunger 4 or changing the plunger cylinder set with a different rod diameter. Between the propulsion shaft 15 and the turntable 16, the slider base 12 and the propulsion slider 11 are all bolted, which can be easily disassembled to adjust the radius of the propulsion shaft 15 on the turntable 16, thereby adjusting the plunger 4 in the cylinder 2 itinerary.

The flow pulsation generator is connected in parallel with the pipeline downstream of the check valve of the main pipeline through a three-way joint. Through the reciprocating linear simple harmonic motion of the plunger 4 in the cylinder 2, the fluid in the main pipeline is continuously sucked into and discharged from the cylinder 2, so that a sinusoidal pulsation is superimposed on the average flow downstream of the main pipeline check valve, forming a pulsation amplitude and a pulsating flow with a fixed period. The amplitude of the pulsation can be easily adjusted by changing the stroke of the plunger 4 in the cylinder 2, and the period of the pulsation can be adjusted by changing the motor speed through a frequency converter.

Claims (3)

1. plunger type flow pulsation generator, comprise pedestal (1), it is characterized in that, guiding linear rail (7,14) be fixed on pedestal (1) sidewall, guiding linear rail (7, guide runner (8 is set respectively 14), 13), advance guide rail base (9) and guide runner (8,13) be fixed together, advance guide rail base (9) front end and plunger (4) end to be connected, plunger (4) front end connects cylinder barrel (2) and end cover (3), cylinder barrel (2) and end cover (3) are fixed on pedestal (1) the front end wall, advance linear rail (10) to be fixed on the guide rail basal plane that advances guide rail base (9), advance the propelling slide block (11) on the linear rail (10) to be connected with the slide block pedestal (12) that has bearing groove, cardan shaft (15) one ends are connected with slide block pedestal (12) by the bearing (19) in the bearing groove, the other end is connected in the positioning hole (17) on rotating disk (16) different radii, rotating disk (16) is connected on the handle (18) that has axle sleeve, is connected the axle sleeve of handle (18) by retarder (5) output shaft of motor (6) driving.

2. plunger type flow pulsation generator according to claim 1, it is characterized in that, positioning hole (17) is for being distributed in the hexagonal hole at the circumferential different radii of rotating disk place, the end that cardan shaft (15) is connected with rotating disk (16) is the hexagonal prism of same size, cardan shaft (15) is fixed on the positioning hole (17) that different rotating disks (16) footpaths makes progress and locates, and produces different plunger strokes.

3. plunger type flow pulsation generator according to claim 1, it is characterized in that: cylinder barrel end cap (3) adopts this special envelope (22) sealed plunger (4), cylinder barrel end cap and cylinder barrel are by being bolted to the pedestal front end, and the end of plunger (4) adopts screw thread to be connected with the upright guide rail pedestal.

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