Jet flow channel window design method, self-operated fast-adjusting control valve and control system

Abstract

The present invention belongs to the technical field of self-operated valves, and specifically relates to a jet flow channel window design method, a self-operated fast-adjusting control valve and a control system. The jet flow channel window design method of the present invention comprises the following steps: S1, obtaining the single group of jet flow channel window areas A under different openings by the following formula j :S2, calculate the theoretical flow rate Q at different openings of the control valve by the following formula j This design method has the advantage of high design accuracy and can effectively improve product development efficiency. The valve core with a jet flow channel window manufactured by this design method can achieve precise feedback adjustment of the control valve. At the same time, combined with the rotary window valve core structure component, it can greatly improve or even eliminate the unbalanced force on the valve core.

Description

Technical Field

[0001] The invention belongs to the technical field of self-operated valves, and in particular relates to a jet flow channel window design method, a self-operated fast-adjustable control valve and a control system. Background Art

[0002] Gas turbine, referred to as gas turbine, is a ship's reliable and stable power unit. When the gas turbine switches between different operating modes such as normal operation, full-speed propulsion, and emergency deceleration, an important prerequisite is that the self-operated control valve located at the gas turbine inlet must perform rapid and accurate automatic feedback adjustment to ensure that the pressure at its oil inlet is stable within the specified range. Obviously, this puts forward stringent requirements on the matching control valve, such as fast response, precise adjustment, and sensitive action.

[0003] The structure of the existing control valve is basically a straight-through type, the valve core and the valve stem are coaxial, and the valve core can move up and down in the vertical direction to open and close and adjust the valve, thereby adjusting the flow rate, which is described in patents CN 208687047 U, CN 204942674 U, CN 213512104 U and CN 214037017 U. However, the above-mentioned straight-through self-operated control valve, referring to Figure 1 As shown in the figure, due to the "S"-shaped structure of the valve flow channel, the fluid will directly impact the bottom end face of the valve core during operation, causing the valve core assembly to be subjected to a large medium unbalanced force, and this unbalanced force shows an unsteady fluctuation trend with the change of the valve opening, resulting in great instability and uncertainty in the internal fluid state of the control valve and the force of the valve core. At the same time, the design of this type of valve adjustment window mostly adopts the method of multiple engineering trial and error, and the adjustment effect and accuracy are difficult to accurately guarantee. In some cases, the above unfavorable factors will even be further superimposed, resulting in the existing self-operated control valve not only having low efficiency and low accuracy in design, but also having a series of problems such as drastic feedback pressure fluctuations, poor adjustment performance, delayed response, slow adjustment, etc. in actual application. Under extreme working conditions, it may even cause the interlocking shutdown failure of the gas turbine, reduce the working life of the gas turbine, and seriously restrict the development of ship power devices. In addition, the above valves also have the defects of large size and heavy weight, which are easy to cause problems such as large installation pipeline load and waste of installation space, and cannot meet the application requirements of miniaturization and lightweight of ship equipment. Therefore, it is urgent to solve. Summary of the invention

[0004] One of the purposes of the present invention is to overcome the deficiencies of the above-mentioned prior art and to provide a method for designing a jet flow channel window. The method has the advantage of high design accuracy and can effectively improve product development efficiency. The valve core with a jet flow channel window manufactured by the method can realize precise feedback adjustment of the control valve. At the same time, in combination with a rotary window valve core structural component, it can greatly improve or even eliminate the unbalanced force on the valve core. Another purpose of the present invention is to provide a self-operated quick-adjusting control valve with a compact and reasonable structure using the above-mentioned jet flow channel window, which can specifically and effectively improve or even eliminate the unbalanced force on the valve core, thereby greatly simplifying the actual force of the valve core, and ultimately ensuring the stability of the internal fluid state of the valve and the force on the valve core. The last purpose of the present invention is to provide a control system using the above-mentioned self-operated quick-adjusting control valve, which has the advantages of precise adjustment, rapid feedback, and stable response.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A jet flow channel window design method, characterized by comprising the following steps:

[0007] S1, the window area A of a single group of jet channels at different openings is obtained by the following formula j :

[0008]

[0009] Where:

[0010] j is the opening of a single group of jet channel windows, j = 0, 10%, 20%, ... 100%;

[0011] n represents the number of jet holes in a single group of jet channel windows;

[0012] ɑ j Indicates the end angle of each layer of jet holes when the control valve is at different openings;

[0013] r i Indicates the centerline inner diameter of each layer of jet holes;

[0014] Δr represents the width of the jet holes in each layer;

[0015] S2. Calculate the theoretical flow rate Q at different openings of the control valve by the following formula j :

[0016]

[0017] Where:

[0018] A 0 Indicates the inlet area of ​​the control valve, in cm 2 ;

[0019] m represents the number of jet channel windows;

[0020] ΔP represents the pressure difference between the inlet and outlet of the control valve, unit: kgf / cm 2 ;

[0021] ρ represents the density of the medium, unit is g / cm 3 ;

[0022] g represents the acceleration due to gravity, in cm / s 2 .

[0023] Preferably, the jet holes are waist-shaped holes of equal width that penetrate the surface of the static valve core plate, and the jet holes are arranged in sequence along the radial direction of the static valve core, and the axes of the hole curves of the jet holes are coaxial with the static valve core; the jet holes that increase in sequence from the inside to the outside with the hole length form a group of jet flow channel windows, and the groups of jet flow channel windows are evenly distributed in sequence around the axis of the static valve core; the static valve core is coaxially and fit-fittingly rotated with a moving valve core at the material inlet surface, and the moving valve core is arranged to produce a staggered action with the jet flow channel window to open and close and adjust the channel fan-shaped holes, and the number of jet flow channel windows is equal to the number of fan-shaped holes; on the same group of jet flow channel windows, the end of the jet hole that the fan-shaped hole first contacts is the front end of the jet hole, the front end of each jet hole and the contacting fan edges of the fan-shaped holes are all located on the same radial line of the static valve core, and the rear end of each jet hole is gradually elongated from the inside to the outside along the radial direction of the static valve core.

[0024] Preferably, a self-operated quick-adjusting control valve using the jet flow channel window design method is characterized in that it includes a valve body, the valve body has a straight cylindrical valve cavity for constituting a flow channel, and the static valve core as a static part is coaxially fixed in the valve cavity; the moving valve core as a moving part is coaxially arranged in the direction of the material incoming surface of the static valve core, and the moving valve core is driven by a power source to produce a close-fitting coaxial rotation action relative to the static valve core.

[0025] Preferably, a rotary shaft is coaxially convexly provided on the material-incoming surface of the static valve core, so as to form a coaxial plug-in fit with the coaxial countersunk hole concavely provided on the movable valve core.

[0026] Preferably, an arc-shaped guide groove is concavely provided on the material inlet surface of the static valve core, the extension direction of the arc-shaped guide groove is in the same direction as the hole length direction of the jet hole and the axes of the curves formed by the two are coaxial with each other; a guide column is convexly provided on the movable valve core and extends axially into the arc-shaped guide groove.

[0027] Preferably, a thrust ball bearing, a bearing seat, an axial spring, a spring seat, a retaining ring and a side cover are arranged in sequence from near to far along the axial direction on the material inlet surface of the moving valve core. The coaxial thread of the side cover is matched with the material inlet end of the valve cavity. The side cover and the spring seat, as well as the spring seat and the inner wall of the valve cavity are sealed to each other through sealing rings.

[0028] Preferably, the power source is used to drive the valve stem to produce reciprocating linear motion along a direction perpendicular to the axis of the moving valve core; the power source includes a shell and a diaphragm located in the shell, the axis of the valve stem is perpendicular to the diaphragm membrane surface and the top end is fixed on the diaphragm, and a rack is arranged at the bottom end of the valve stem to form a meshing relationship with the gear-shaped moving valve core; the diaphragm divides the inner cavity of the shell into an upper pressure chamber and a lower pressure chamber, thereby relying on the pressure changes in the upper pressure chamber and the lower pressure chamber to drive the diaphragm to produce reciprocating motion, and then drive the valve stem to drive the moving valve core to produce a rotational motion.

[0029] Preferably, a small diameter section is arranged at the top end of the valve stem, and the shoulder formed by the small diameter section and the top end of the valve stem is pressed against the lower membrane surface of the diaphragm from bottom to top. After the small diameter section passes through the diaphragm, it is tightened in sequence through the diaphragm plate and the fastening nut; the top end of the compression spring is pressed against the top wall of the upper pressure chamber, and the bottom of the compression spring is pressed against the spring adjusting seat. After the adjusting screw passes through the top wall of the upper pressure chamber from the outside to the inside, the coaxial thread is engaged with the spring adjusting seat.

[0030] Preferably, the compression springs are in three groups and are coaxially and evenly distributed in sequence from the inside to the outside.

[0031] Preferably, the control system using the self-operated quick-adjusting control valve is characterized in that a pressure-taking interface is provided at the lower pressure chamber, and the pressure-taking interface is connected to the fluid at the flow channel in the incoming direction through a feedback pipe.

[0032] The beneficial effects of the present invention are:

[0033] 1) The design method of the present invention has a very high design accuracy, greatly improving the efficiency of product development, and filling the gap in the theoretical calculation of this type of new structure valve, which can provide a data basis for subsequent research by engineers. The valve core with a jet flow channel window manufactured by this design method can greatly improve the feedback adjustment accuracy of the control valve, with remarkable results.

[0034] 2) Specifically, the valve holes of the moving valve core and the static valve core of the present invention can be staggered to form a flow area, thereby achieving pressure regulation. During the design, the static valve core adopts a multi-layer jet flow channel uniform distribution structure design. The jet flow channels at a single flow channel window are proportionally radiated and enlarged in sequence along the radial direction from the center of the flow channel and are evenly arranged. The overall structure is similar to the shape of wifi. When the opening is small, the medium is ejected from the staggered holes on the edge of the far end of wifi. The jet effect of the multi-hole uniform distribution can offset the external force to make the valve core more uniformly stressed and the flow more stable. When the opening is large, the staggered holes at the near end of wifi play a flow compensation role, which can quickly and accurately adjust the pressure, so that the feedback is timely and stable, and the pressure fluctuation and lag at the inlet of the engine are avoided. In addition, from the perspective of overall flow effect, compared with the existing control valves, the multi-layer jet flow channel structure of the present invention has a multi-level diversion effect, thereby producing a porous jet effect. The medium is sucked and mixed behind the valve to form multiple strong shear energy dissipation zones, which greatly reduces the scouring of the valve internals by the medium. This phenomenon is more obvious at small openings. When the existing control valves are at a small opening, the medium will severely erode the valve seat and valve core, and even cavitation will occur under extreme conditions, reducing the life of the valve. However, the present invention discharges the medium directly into the middle cavity area behind the valve through the porous jet effect at a small opening, thereby avoiding the scouring of the valve internals and greatly reducing the flow-induced noise of the control valve.

[0035] 3) The present invention realizes a self-tightening and sealing structural design by arranging the moving valve core at the material-incoming surface of the static valve core. When the present invention is in a closed state, the pressure of the fluid medium tightly presses the moving valve core against the static valve core, producing a self-tightening and sealing effect, so that the leakage of the control valve is extremely small after closing. At the same time, during the control process, the moving valve core rotates and slides with the static valve core around the flow channel axis, just like self-grinding, which can ensure the leakage for a long time, and thus has the advantages of good sealing, simple structure, and small maintenance workload.

[0036] 4) Both valve cores of the present invention adopt a uniformly distributed structure design of multiple jet flow channel windows, so that the movement of the valve stem per unit stroke can trigger the linkage of multiple strokes of the valve core. Taking four sets of jet flow channel windows as an example, the moving valve cores of the four fan-shaped holes can be linked to the static valve core with four sets of jet flow channel windows, and the four windows can be adjusted simultaneously; compared with the traditional control valve, under the same parameter conditions, the adjustment stroke of the present invention only accounts for 1 / 4 of the existing structure, with the advantages of short adjustment stroke, fast response speed, precise and stable, and can also achieve fast response and precise adjustment under small opening conditions.

[0037] 5) Based on the above valve core structure, considering that the existing self-operated control valve valve core is subjected to complex forces, in addition to the gravity and friction of the valve core assembly itself, it is also subjected to the unbalanced force of unsteady fluctuations and instantaneous impacts during the entire movement process; when designing, engineers usually ignore the instantaneous impact and simplify the fluctuating unbalanced force to a constant value for processing, resulting in a series of problems such as poor adjustment performance, severe pressure fluctuations, and delayed response in the actual working process of the control valve. In comparison, the present invention adopts a direct current structure design, and the moving valve core reciprocates around the center of the flow channel. The whole set of valve cores is not disturbed by gravity during movement, and the porous surrounding uniformly distributed structure of the valve hole can also offset the force of the fluid, free from the impact of the fluid, and the unbalanced force is 0; that is, the moving valve core and the static valve core of the present invention only need to be subjected to a very small friction force during the entire movement process, which greatly simplifies the force of the corresponding valve core, ensures the stability of the internal fluid state of the valve and the force of the valve core, and has the advantages of precise adjustment, rapid feedback, and stable response.

[0038] 6) The valve stem and the moving valve core of the present invention adopt an eccentric structure design, and the valve stem and the moving valve core are not on the same plumb line. With the aforementioned multi-window design, the height of the present invention is greatly reduced after comprehensive accumulation. In addition, the whole valve can be connected with a compact clamping structure, which has the advantages of small size and light weight, is easy to install, and can further meet the design requirements of miniaturization and lightweight.

[0039] 7) The valve stem of the present invention drives the moving valve core to rotate around the flow channel axis through the gear rack meshing mode, and cooperates with the guide column and the arc guide groove to ensure the controllability of the moving valve core's movement stroke. At the same time, the moving valve core is only subjected to the rotational friction caused by the medium and the spring force of the axial spring during the entire movement process. Since the sealing surfaces of the moving valve core and the static valve core can be ground before assembly, and the thrust ball bearing prevents the moving valve core from being disturbed by other external forces when rotating, coupled with the self-lubricating property of the fuel medium itself, this rotational friction is negligible, which can greatly extend the actual service life of the control valve of the present invention, with significant results. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a force diagram of a traditional self-operated control valve;

[0041] Figure 2 It is a structural schematic diagram of the self-operated quick-adjusting control valve of the present invention;

[0042] Figure 3 It is a schematic diagram of the matching state of the moving valve core, the moving valve core and the valve stem;

[0043] Figure 4 This is the coordination diagram of the moving valve core and the static valve core when the flow channel is fully open;

[0044] Figure 5 This is the coordination diagram of the moving valve core and the static valve core when the flow channel is half open;

[0045] Figure 6 This is a diagram showing the coordination of the moving valve core and the static valve core when the flow channel is closed;

[0046] Figure 7 It is a force analysis diagram of the self-operated quick-adjusting control valve of the present invention;

[0047] Figure 8 It is the assembly drawing of the components in the valve cavity;

[0048] Fig. 9 It is a structural schematic diagram of the control system of the present invention;

[0049] Fig.10 The comparative analysis diagram of the valve core opening and the unbalanced force of the conventional self-operated control valve and the valve core of the present invention under the DN200 caliber;

[0050] Fig.11 is a theoretical model of the jet flow channel window of the present invention;

[0051] Fig.12 These are the pressure and velocity cloud diagrams when the control valve is at 80% opening.

[0052] The actual correspondence between the reference numerals and component names of the present invention is as follows:

[0053] a-upper pressure chamber; b-lower pressure chamber;

[0054] 10-valve body; 20-static valve core; 21-jet hole; 22-arc guide groove;

[0055] 30-moving valve core; 31-sector-shaped hole; 32-guide column;

[0056] 40-power source; 41-housing; 42-diaphragm; 43-diaphragm plate; 44-fastening nut;

[0057] 45-compression spring; 46-spring adjustment seat; 47-adjusting screw; 48-pressure taking interface;

[0058] 49-Feedback tube;

[0059] 50-rotating shaft; 61-thrust ball bearing; 62-bearing seat; 63-axial spring;

[0060] 64-spring seat; 65-retaining ring; 66-side cover; 67-sealing ring;

[0061] 70-valve stem; 71-rack. DETAILED DESCRIPTION

[0062] For ease of understanding, here we combine Figure 1-12 The specific structure and working mode of the present invention are further described as follows:

[0063] The design method of the present invention is specifically embodied by the following embodiment 1:

[0064] Embodiment 1:

[0065] This embodiment 1 takes a DN100 caliber control valve as an example, and matches Fig.11 The jet hole 21 is wifi-shaped, and the jet channel window formed by the jet hole 21 is a four-window evenly distributed structure.

[0066] At this time, the number of jet holes in a single group of jet channel windows is 7, that is, m=4, n=7, and the width of the jet hole 21 Δr=5 mm. Here, three typical openings of j=20%, j=50%, and j=80% are selected to calculate the flow rate of the control valve.

[0067] When the opening is 20%, that is, when j = 20%, according to Fig.11 The following formula is used to calculate the flow area of ​​a single set of jet channel windows, where the upper and lower limits of the double integral interval are as follows:

[0068]

[0069]

[0070] Substituting the above boundary conditions into the formula, we get:

[0071]

[0072] That is, when the opening is 20%, the window area of ​​the single jet flow channel of the control valve is A. 20％ =0.52cm 2 .

[0073] Then, the flow calculation formula under different opening degrees of the control valve is obtained as follows:

[0074]

[0075] Where:

[0076] Q j Indicates the theoretical calculated flow rate under different opening degrees of the control valve, m 3 / h;

[0077] A 0 Indicates the inlet area of ​​the control valve, cm 2 ;

[0078] m represents the number of multi-layer jet flow channel groups of the control valve (m=1, 2, 3...);

[0079] ΔP represents the pressure difference between the inlet and outlet of the control valve, which is 100kgf / cm 2 ;

[0080] ρ represents the medium density, which is 1g / cm 3 ;

[0081] g represents the acceleration due to gravity, which is 981 cm / s 2 ;

[0082] From the design parameters, we know that A 0 =Π / 4*DN 2 =78.5cm 2 ,have to:

[0083]

[0084] The control valve with 20% opening is modeled in three dimensions, and numerical simulation is performed using fluid mechanics to obtain a simulated flow rate value of 3.5m 3 / h.

[0085] Similarly, according to the above process, the calculated flow and simulated flow of the control valve at 50% and 80% opening are calculated respectively. The pressure cloud diagram and velocity cloud diagram at 80% opening of the control valve are as follows: Fig.12 As shown, no further details are given here; at the same time, the relative error between the theoretical and simulated flow rates is calculated, and the results are shown in Table 1:

[0086] Table 1 Flow coefficient and error at typical opening of DN100 control valve

[0087]

[0088] Conclusion: As shown in Table 1, as the opening of the control valve increases, the calculated flow rate and the simulated flow rate gradually increase. The simulated flow rate values ​​under typical openings are all greater than the calculated flow rate values. This is due to the local simplification of the model during numerical simulation, while ignoring the influence of factors such as roughness on the flow rate. In addition, the relative error between the calculated flow rate and the simulated flow rate is about 8%, which is within the range allowed by engineering errors and technical requirements, verifying the correctness of the theoretical design.

[0089] It can be seen that the design method proposed in the present invention has a very high design accuracy, which greatly improves the efficiency of product research and development. At the same time, it fills the gap in theoretical calculation of this type of new structure valve and provides a data basis for subsequent research by engineers.

[0090] Based on the above design method, the present invention provides an improved control valve structure, specifically as follows Figure 2-9 As shown, the main body includes an adjustment mechanism and a control mechanism constituting a power source 40, wherein:

[0091] The regulating structure is the main valve component, including the valve body 10, the valve stem 70, the moving valve core 30, the static valve core 20 and the corresponding pressure regulating unit. Figure 2-3 As shown, the valve stem 70 and the movable valve core 30 are driven by gear rack engagement; when the valve stem 70 reciprocates up and down along the axial direction, it can drive the movable valve core 30 to reciprocate and rotate around the axis of the flow channel. Figure 2 As shown, an O-ring is sleeved on the valve stem 70 to ensure that the pressures in the lower pressure chamber b and the valve chamber do not interfere with each other.

[0092] As for the pressure regulating unit, Figure 7-8 As shown, it includes a side cover 66, a retaining ring 65, a spring seat 64, an axial spring 63, a bearing seat 62 and a thrust ball bearing 61 arranged in sequence from left to right. Figure 8 It can be seen that the static valve core 20 is fixed in the valve cavity by the positioning pin, and the static valve core 20 and the thrust ball bearing 61 cooperate with each other to clamp the dynamic valve core 30. At this time, the dynamic valve core 30 is tightly fitted on the static valve core 20. In order to prevent medium leakage, a sealing ring 67 is arranged between the outer ring surface of the spring seat 64 and the inner wall of the valve cavity, and between the side cover 66 and the inner ring surface of the spring seat 64.

[0093] During specific assembly, the static valve core 20 is placed in the middle of the valve cavity and is fixed to the valve body 10 through the positioning pin. The dynamic valve core 30 is coaxially arranged with the static valve core 20 using the rotary shaft 50, and forms a gear rack meshing with the rack 71 at the valve stem 70. The thrust ball bearing 61 is placed in the bearing seat 62 and abuts against the incoming surface of the dynamic valve core 30. Multiple groups of axial springs 63 are evenly distributed in the spring seat 64, and the spring seat 64 is coaxially placed in the valve cavity and sealed by an O-ring. The retaining ring 65 can use an elastic retaining ring and be inserted into the preset groove at the incoming end of the valve body 10, so as to achieve the fit between the spring seat 64 and the bearing seat 62, and also provide an initial preload force for the dynamic valve core 30. The side cover 66 is threadedly connected to the valve body 10.

[0094] like Figure 3 As shown, when the present invention is working, the valve stem 70 reciprocates along the vertical axial direction, driving the moving valve core 30 to reciprocate around the flow channel rotary axis 50, and the windows of the moving valve core 30 and the static valve core 20 are staggered to form a fluid channel to achieve flow regulation. The static valve core 20 is provided with a semi-sunk hole-shaped arc guide groove 22 on the side that fits the moving valve core 30, that is, the material-incoming surface of the static valve core 20, so as to limit the moving stroke of the moving valve core 30 through the guiding action of the guide column 32 at the moving valve core 30, so as to ensure that the moving valve core 30 works within the preset stroke.

[0095] by Figure 2-6Taking the four-window structure shown as an example, in the present invention, the moving valve core 30 is not affected by gravity during the entire movement process. This is because the valve hole uniform distribution scheme of the present invention can make the impact effect of the fluid converge at the fan-shaped hole 31 of the moving valve core 30, and collide and offset each other due to the matching action of a group of fan-shaped holes 31 and multiple groups of jet holes 21. The moving valve core 30 is only subjected to the friction force generated by the medium force and the spring force acting on the end face and the static valve core 20 during the rotational movement; at the same time, multi-window designs such as four windows also have a multi-level diversion effect, thereby producing a multi-porous jet effect. The medium is sucked and mixed behind the valve to form multiple strong shear energy dissipation zones, which effectively reduce the scouring effect of the medium on the inner wall behind the valve.

[0096] In the specific design, on the same group of jet flow channel windows, the end of the jet hole 21 that the fan-shaped hole 31 first contacts is the front end of the waist-shaped jet hole 21, and the front end of each jet hole 21 and the contacting fan edge of the fan-shaped hole 31 are all located on the same radial line of the static valve core 20, and the rear end of each jet hole 21 is gradually elongated from the inside to the outside along the radial direction of the static valve core 20; that is, the hole width and interval of each jet hole 21 remain unchanged, while the length increases successively in the rotation direction of the moving valve core 30, and the overall structure forms a shape that is similar to "wifi" tilted to one side. When the guide column 32 of the moving valve core 30 moves in the arc-shaped guide groove 22 of the static valve core 20, the valve holes at the two groups of valve cores naturally produce staggered fluid channels, and finally achieve the following Figure 4-6 The adjustment effect is shown.

[0097] As for the control mechanism, it is mainly composed of a diaphragm 42, a compression spring 45, an adjusting screw 47, a pressure-taking interface 48 and other components. Figure 2 As shown, the whole set of control structure can be placed in the cavity of the housing 41 formed by the flange matching of the upper cover and the valve body 10, and the cavity of the housing 41 can be divided into an upper pressure chamber a and a lower pressure chamber b by means of the diaphragm 42, and the lower pressure chamber b is connected to the flow channel in the incoming direction through the pressure-taking interface 48 and the feedback pipe 49, that is, the inlet of the engine. A small diameter section is arranged at the top of the valve stem 70, and the shoulder formed by the small diameter section and the top of the valve stem 70 is pressed against the lower membrane surface of the diaphragm 42 from bottom to top. The small diameter section passes through the diaphragm 42 and is pressed by the diaphragm plate 43 and the fastening nut 44 in sequence. The top of the compression spring 45 is pressed against the top wall of the upper pressure chamber a, and the bottom of the compression spring 45 is pressed against the spring adjustment seat 46. The adjusting screw 47 passes through the top wall of the upper pressure chamber a from outside to inside and then is coaxially threaded and matched with the spring adjustment seat 46. By rotating the adjusting screw 47, the online control of the spring force of the control mechanism can be realized. The spring adjustment seat 46 itself can be formed by assembling multiple parts, which will not be described in detail here.

[0098] When the present invention is actually used, the stress state at the diaphragm 42 is referred to Fig. 9 As shown, the valve core stress state refers to Figure 7At this time, the pressure P1 at the inlet of the engine is guided to the lower pressure chamber b at the control mechanism through the feedback pipe 49, and the pressure acts on the bottom of the diaphragm 42 as shown in FIG. Fig. 9 As shown, a vertically upward medium force F1 is generated, and a spring force F2 is applied on the diaphragm 42 .

[0099] When the pressure P1 at the inlet of the engine decreases, F1<F2, the compression spring 45 will drive the diaphragm 42 and the valve stem 70 to move downward, at which time the movable valve core 30 rotates around the flow channel axis, the valve holes are staggered and the staggered window area is gradually reduced, thereby achieving the purpose of increasing the pressure P1 at the inlet of the engine;

[0100] Vice versa, when the pressure P1 at the engine inlet increases, F1>F2, the compression spring 45 drives the diaphragm 42 and the valve stem 70 to move upward, at which time the movable valve core 30 rotates around the flow channel axis, the valve holes are staggered and the staggered window area is gradually increased, thereby achieving the purpose of reducing the pressure P1 at the engine inlet;

[0101] Such repeated rapid response and precise adjustment can ensure that the pressure at the turbine inlet is stable within the designed range, thereby ensuring safe, reliable and stable operation of the system.

[0102] Figure 7 This is a schematic diagram of the unbalanced force of the present invention. The moving valve core 30 reciprocates around the center of the flow channel, and the fluid medium goes in and out directly. The moving valve core 30 is not disturbed by gravity during movement. The multi-layer jet flow channel structure can offset the force of the fluid and avoid the impact of the fluid. The unbalanced force Fb' on the control valve is 0, which greatly simplifies the force condition of the valve core and has the advantages of precise adjustment, rapid response and stable feedback.

[0103] For ease of comparison, Figure 1 It also gives a force diagram of the existing self-operated control valve; the flow channel structure of this type of valve is "S" shaped, and the fluid directly impacts the bottom end face of the valve core, causing the valve core assembly to be subjected to a large medium unbalanced force, and this unbalanced force shows an unsteady fluctuation trend with the change of the valve opening. At present, when calculating the unbalanced force Fb, engineering and technical personnel all simplify it to a constant value based on the industry design manual, without considering the error caused by the pressure difference fluctuation before and after the valve at different openings of the control valve, which makes the control valve often have a series of problems such as severe pressure fluctuations, delayed response, and poor adjustment performance during actual operation; the calculation formula is shown as follows:

[0104]

[0105] Where:

[0106] Fb represents the unbalanced force, in N;

[0107] ds represents the valve stem diameter, in mm;

[0108] dg represents the valve core diameter, in mm;

[0109] P1 represents the upstream pressure, in mPa;

[0110] P2 represents the downstream pressure in mPa.

[0111] Furthermore, for the sake of illustration, Figure 7 The present invention and Figure 1 The existing control valve shown in the figure is subjected to comparative analysis of valve core unbalance force at DN200 caliber, in order to obtain an intuitive comparison at calibers with the same parameters. Fig.10 shown.

[0112] Fig.10 It can be clearly seen that:

[0113] The unbalanced force on the existing control valve during the entire adjustment stroke shows an unsteady fluctuation trend. Fig.10 As shown, for the low-inlet and high-outlet type, which is the existing flow-closing type, as the opening increases, the unbalanced force gradually decreases and then tends to be stable; for the high-inlet and low-out type, which is the existing flow-opening type, as the opening increases, the unbalanced force gradually decreases to 0, then changes direction and gradually increases again. The unbalanced force interferes with the movement of the valve core, causing feedback pressure fluctuations and poor regulation performance.

[0114] The present invention balances the valve trim structure by changing the relationship between the movement mode of the valve core and the fluid force, and offsets the fluid force by dissipating energy, such as Fig.10 As shown, the unbalanced force on the valve core during movement is always 0, which obviously greatly simplifies the force condition of the valve core. It can be seen that the adjustment is effective and accurate.

[0115] Of course, it will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, but also includes the same or similar structures that can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0116] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0117] The techniques, shapes, and structural parts not described in detail in the present invention are all well-known techniques.

Claims

1. A jet flow channel window design method, characterized in that The following steps are involved: S1, the window area A of a single group of jet channels at different openings is obtained by the following formula j : Where: j is the opening of a single group of jet channel windows, j = 0, 10%, 20%, ... 100%; n represents the number of jet holes (21) in a single group of jet channel windows; ɑ j Indicates the end angle of each layer of jet holes (21) when the control valve is at different opening degrees; r i represents the centerline inner diameter of each layer of jet holes (21); Δr represents the width of the jet holes (21) of each layer; S2. Calculate the theoretical flow rate Q at different openings of the control valve by the following formula j : Where: A0 represents the inlet area of ​​the control valve, in cm 2 ; m represents the number of jet channel windows; ΔP represents the pressure difference between the inlet and outlet of the control valve, unit: kgf / cm 2 ; ρ represents the density of the medium, in g / cm 3 ; g represents the acceleration due to gravity, in cm / s 2 ; The jet holes (21) are waist-shaped holes of equal width that penetrate the plate surface of the static valve core (20), and the jet holes (21) are sequentially arranged along the radial direction of the static valve core (20), and the axes of the hole curves of the jet holes (21) are coaxial with the static valve core (20); the jet holes (21) whose hole lengths increase sequentially from the inside to the outside form a group of jet flow channel windows, and the groups of jet flow channel windows are uniformly distributed in sequence around the axis of the static valve core (20); the static valve core (20) is coaxially and fit-fittingly rotatably matched with the moving valve core (30), and the moving valve core (30) ) are arranged on the static valve core (20) to produce a staggered action with the jet flow channel window so as to open, close and adjust the flow channel fan-shaped hole (31), the number of the jet flow channel windows is equal to the number of the fan-shaped holes (31); on the same group of jet flow channel windows, the end of the jet hole (21) that the fan-shaped hole (31) first contacts is the front end of the jet hole (21), the front end of each jet hole (21) and the contacting fan edge of the fan-shaped hole (31) are all located on the same radial line of the static valve core (20), and the rear end of each jet hole (21) is gradually elongated from the inside to the outside along the radial direction of the static valve core (20); The invention comprises a valve body (10), wherein the valve body (10) has a straight-cylindrical valve cavity for forming a flow channel, wherein a static valve core (20) as a static part is coaxially fixed in the valve cavity; a movable valve core (30) as a dynamic part is coaxially arranged in the direction of the material inlet surface of the static valve core (20), and the movable valve core (30) is driven by a power source (40) to generate a coaxial rotational movement relative to the static valve core (20) in a fitted manner.

2. A self-operated fast-adjustable control valve using the jet flow channel window design method of claim 1, characterized in that: A rotary shaft (50) is coaxially convexly provided on the material inlet surface of the static valve core (20), so as to form a coaxial plug-in fit with a coaxial countersunk hole concavely provided on the movable valve core (30).

3. The self-operated fast-adjustable control valve according to the jet flow channel window design method of claim 2, characterized in that: An arc-shaped guide groove (22) is concavely provided on the material-incoming surface of the static valve core (20), the extension direction of the arc-shaped guide groove (22) is in the same direction as the hole length direction of the jet hole (21), and the axes of the curves formed by the two are coaxial with each other; a guide column (32) is convexly provided on the movable valve core (30) and extends axially into the arc-shaped guide groove (22).

4. The self-operated fast-adjustable control valve according to the jet flow channel window design method according to claim 2 or 3, characterized in that: A thrust ball bearing (61), a bearing seat (62), an axial spring (63), a spring seat (64), a retaining ring (65) and a side cover (66) are arranged in sequence from near to far along the axial direction on the material inlet surface of the movable valve core (30). The coaxial thread of the side cover (66) is matched with the material inlet end of the valve cavity. The side cover (66) and the spring seat (64) as well as the spring seat (64) and the inner wall of the valve cavity are sealed to each other through a sealing ring (67).

5. The self-operated fast-adjustable control valve according to the jet flow channel window design method according to claim 2 or 3, characterized in that: The power source (40) is used to drive the valve stem (70) to generate a reciprocating linear motion along the direction perpendicular to the axis of the movable valve core (30); the power source (40) comprises a housing (41) and a diaphragm (42) located in the housing (41); the axis of the valve stem (70) is perpendicular to the membrane surface of the diaphragm (42) and the top end is fixed on the diaphragm (42); a rack (71) is arranged at the bottom end of the valve stem (70) so as to form a meshing relationship with the gear-shaped movable valve core (30); The diaphragm (42) divides the inner cavity of the housing (41) into an upper pressure cavity (a) and a lower pressure cavity (b), so that the pressure change between the upper pressure cavity (a) and the lower pressure cavity (b) drives the diaphragm (42) to produce a reciprocating motion, thereby driving the valve stem (70) to drive the valve core (30) to produce a rotating motion.

6. The self-operated fast-adjustable control valve according to the jet flow channel window design method of claim 5, characterized in that: A small diameter section is arranged at the top end of the valve stem (70), and the shoulder formed by the small diameter section and the top end of the valve stem (70) is pressed against the lower membrane surface of the diaphragm (42) from bottom to top. The small diameter section passes through the diaphragm (42) and is tightened in sequence through the diaphragm plate (43) and the fastening nut (44); the top end of the compression spring (45) is pressed against the top wall of the upper pressure chamber (a), and the bottom of the compression spring (45) is pressed against the spring adjustment seat (46). The adjusting screw (47) passes through the top wall of the upper pressure chamber (a) from the outside to the inside and is coaxially threadedly engaged with the spring adjustment seat (46).

7. The self-operated fast-adjustable control valve according to the jet flow channel window design method of claim 6, characterized in that: The compression springs (45) are in three groups and are coaxially and evenly distributed in sequence from the inside to the outside.

8. A control system for a self-operated fast-adjustable control valve using the jet flow channel window design method of claim 5, characterized in that: A pressure-taking interface (48) is provided at the lower pressure chamber (b), and the pressure-taking interface (48) is connected to the fluid at the flow channel in the incoming direction through a feedback pipe (49).

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