Novel valve element runner structure of labyrinth type regulating valve and design method

Abstract

The invention discloses a novel valve element runner structure of a labyrinth type regulating valve and a design method, and belongs to the technical field of fluid mechanics. The valve element runner structure comprises a plurality of stages of pressure reduction structures which are sequentially arranged from a valve element inlet to a valve element outlet, and the diameters of the pressure reduction structures are sequentially decreased from the valve element inlet to the valve element outlet. A plurality of stages of pressure reduction structures from the inlet of the valve core adopt cylindrical throttling structures; the multiple stages of pressure reduction structures close to an outlet of the valve element are streamline throttling structures. The cylindrical throttling structures and the streamline throttling structures are arranged on the valve element disc in an array mode. The streamline throttling structure comprises a cylinder and two veneering shapes; the cylinder is located in the middle, and the two facing shapes are arranged on the two sides of the cylinder respectively. And one end of any veneer shape is connected with the cylindrical edge in a tangent manner, and the other end of any veneer shape is connected with the non-cylindrical connecting end of the other tangent surface shape. The cavitation rate of a runner outlet can be effectively reduced, and the flow capacity of the valve element is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of fluid mechanics, and in particular relates to a novel valve core flow channel structure and a design method of a labyrinth regulating valve. Background Art

[0002] The energy and power systems in the fields of electricity, petroleum, and chemical industry in China are constantly developing in the direction of large capacity, high parameters, and high efficiency. The upstream and downstream pressure differences of the currently commercialized supercritical and ultra-supercritical units are as high as tens of MPa. As the key equipment for regulating pressure and flow in the system, the high pressure difference poses a severe challenge to its performance and stability. The labyrinth regulating valve can effectively control the fluid velocity and pressure drop trend in the valve, and alleviate phenomena such as cavitation, noise, and vibration. The labyrinth regulating valve is mainly composed of valve cover, valve stem, sealing packing, valve core, valve seat, and valve body. The surface of the valve core throttling disc is processed into multiple labyrinth flow channels by chemical etching process, and the labyrinth regulating valve core is stacked and welded by vacuum diffusion welding process. When the fluid passes through the labyrinth flow channel, energy dissipation is generated, which reduces the pressure and controls the cavitation degree inside the valve body.

[0003] However, the dimensions of the inlet and outlet of the labyrinth regulating valve core flow channel are much smaller than those of the valve inlet and outlet. Usually, the inlet and outlet dimensions of the labyrinth flow channel are ≤5mm, which limits the maximum flow capacity of the labyrinth regulating valve. The flow channel of the labyrinth regulating valve core is usually composed of multiple levels of angles. As the pressure difference between the upstream and downstream of the valve increases, the number of angles of the flow channel shows an increasing trend, which further increases the flow resistance of the valve core. Therefore, it is difficult for conventional labyrinth regulating valves to take into account flow rate control, energy dissipation and high fluidity. According to the 2023 paper "Optimization of Control Valve Flow Channel Structure Based on Multi-Objective Genetic Algorithm and Back Propagation Neural Network" published in Volume 40, Issue 12 of "Mechanical and Electrical Engineering", even if a labyrinth regulating valve is used, there is still serious cavitation when the outlet pressure is close to normal pressure, which is specifically manifested as the gas phase volume fraction at the outlet of the labyrinth flow channel is too high. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the above-mentioned related art at least to a certain extent.

[0005] To this end, the purpose of the present invention is to provide a new valve core flow channel structure and design method for a labyrinth-type regulating valve, which can effectively reduce the cavitation rate of the flow channel outlet and improve the flow capacity of the valve core.

[0006] In order to solve the above-mentioned technical problems, the present invention is achieved as follows:

[0007] The embodiment of the present invention provides a novel valve core flow channel structure of a labyrinth-type regulating valve, wherein the valve core flow channel structure includes a plurality of pressure-reducing structures arranged in sequence from the valve core inlet to the valve core outlet, and the diameter of the pressure-reducing structures decreases in sequence from the valve core inlet to the valve core outlet;

[0008] Several stages of pressure reduction structures starting from the valve core inlet adopt cylindrical throttling structures; several stages of pressure reduction structures close to the valve core outlet adopt streamlined throttling structures; both the cylindrical throttling structures and the streamlined throttling structures are arranged in an array on the valve core disc.

[0009] In addition, the novel valve core flow channel structure of the labyrinth regulating valve according to the present invention may also have the following additional technical features:

[0010] In some of the embodiments, the streamlined throttling structure includes a cylinder and two veneer shapes; the cylinder is located in the middle, and the two veneer shapes are arranged on both sides of the cylinder; one end of any veneer shape is tangentially connected to the edge of the cylinder, and the other end is connected to the non-cylindrical connecting end of another tangent shape.

[0011] In some of the embodiments, the veneer shape is an eccentric circular surface whose diameter is twice the diameter of the cylinder.

[0012] In some of the embodiments, the diameter of the cylindrical throttling structure decreases from the valve core inlet to the valve core outlet.

[0013] In some of the embodiments, the diameter of the cylinder of the streamlined throttling structure decreases from the valve core inlet to the valve core outlet.

[0014] In some of the embodiments, the angle α of the cylindrical throttling structure ranges from 5°≤α≤15°.

[0015] The embodiment of the present invention further provides a method for designing a novel valve core flow channel structure of a labyrinth regulating valve, which is used to design a novel valve core flow channel structure of a labyrinth regulating valve as described in any of the preceding items; the steps of the method include:

[0016] S1. Obtain the distance coefficient Δx, valve core outer diameter L, valve core inner diameter l and expansion coefficient k, and calculate the first-stage cylindrical throttling structure circumscribed radius S based on the acquired data 1 , the innermost inscribed radius S of the final throttling structure n , the number of throttling structures n in the valve core flow channel;

[0017] S2. Determine the width w of the first-stage flow channel 1 ;

[0018] S3, determine the cylindrical throttling structure angle α;

[0019] S4, according to the first-stage cylindrical throttling structure circumscribed radius S 1 、Width of first-stage flow channel w 1 The radius R of the first-stage cylindrical throttling structure is calculated by the angle α between the cylindrical throttling structure and the cylindrical throttling structure. 1 ;

[0020] S5. Calculate the circumscribed radius S of the i-th cylindrical throttling structure i , the radius R of the i-th cylindrical throttling structure i , 1<i≤n;

[0021] S6. Determine whether the flow channel structure currently designed can be arranged on the current valve core by size; if not, return to S1.

[0022] In addition, the design method of the novel valve core flow channel structure of the labyrinth regulating valve according to the present invention may also have the following additional technical features:

[0023] In some embodiments, in step S1:

[0024] Calculate the first-stage cylindrical throttling structure circumscribed radius S according to the distance coefficient Δx and the valve core outer diameter L 1 ;

[0025] The innermost inscribed radius S of the final throttling structure is calculated based on the distance coefficient Δx and the inner diameter l of the valve core. n ;

[0026] According to the number of rotation angles n c Calculate the number n of cylindrical throttling structures in the valve core flow channel.

[0027] In some embodiments, in step S5:

[0028] According to the circumscribed radius S of the i-1th cylindrical throttling structure i-1 , the radius R of the i-1th cylindrical throttling structure i-1 , distance coefficient Δx and expansion coefficient k to calculate the circumscribed radius S of the i-th cylindrical throttling structure i ;

[0029] According to the circumscribed radius S of the i-th cylindrical throttling structure i 、Width w of the i-th flow channel i , the cylindrical throttling structure angle α, the distance coefficient Δx and the expansion coefficient k are used to calculate the radius R of the i-th cylindrical throttling structure i .

[0030] In some implementations, the content of the size determination in step S6 includes:

[0031] Calculate the maximum radial arrangement dimension D of the valve core and the outer diameter dimension H of the flow channel structure;

[0032] Determine whether D≥H holds true; if so, it means that the currently designed flow channel structure can be arranged on the current valve core, and the design is completed; otherwise, it means that the currently designed flow channel structure cannot be arranged on the current valve core, and return to step 1 for redesign.

[0033] Compared with the prior art, the present invention has at least the following beneficial effects:

[0034] In the embodiment of the present invention, the novel valve core flow channel structure and design method of the labyrinth regulating valve provided utilizes the vortex and impact generated by the multiple flow diversion and confluence of the fluid in the cylindrical array to dissipate energy, and still maintains a good flow rate control effect when the upstream and downstream pressure differences are large;

[0035] In the embodiment of the present invention, the novel valve core flow channel structure and design method of the labyrinth regulating valve provided adopts a structural design combining a cylindrical wall surface and a streamlined wall surface, which can significantly reduce the influence of the valve core wall effect on the fluid, thereby effectively reducing the resistance of the valve core structure and improving the fluid mass flow rate;

[0036] In the embodiment of the present invention, the novel valve core flow channel structure and design method of the labyrinth regulating valve provided is designed with a special streamlined spoiler structure at the outlet on the basis of the labyrinth throttling structure, which can significantly reduce the influence of the wake area of ​​the throttling structure on the flow field, improve the uniformity of the flow field, reduce pressure loss, reduce the local low-pressure area and reduce the cavitation rate;

[0037] In the embodiment of the present invention, the new valve core flow channel structure and design method of the labyrinth-type regulating valve provided can complete the replacement of the existing valve core without changing other structural components of the existing valve, thereby achieving the effect of reducing the internal cavitation rate of the valve and the valve core structural resistance, and improving the flow capacity of the valve.

[0038] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A flow chart of a method for designing a flow channel structure of a labyrinth valve core disclosed in one embodiment of the present invention;

[0040] Figure 2 A schematic diagram of a labyrinth valve core flow channel disclosed in one embodiment of the present invention;

[0041] Figure 3 A diagram showing parameters of a labyrinth flow channel disclosed in an embodiment of the present invention;

[0042] Figure 4 A schematic diagram of a streamlined spoiler structure of a labyrinth flow channel disclosed in one embodiment of the present invention;

[0043] Figure 5 This is a comparison chart of the outlet cavitation rates of the valve core flow channel structure disclosed in one embodiment of the present invention and the existing structure. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] The embodiments of the present invention are described in detail below through specific embodiments and application scenarios in conjunction with the accompanying drawings.

[0046] In some embodiments of the present invention, a new valve core flow channel structure and design method of a labyrinth-type regulating valve are provided. The valve core flow channel structure of the designed new labyrinth-type regulating valve adopts a throttling structure that combines a cylindrical type and a streamlined type, and is arranged in an array on a valve core disc. Each circle of throttling cylindrical structure from the valve core inlet to the valve core outlet is a first-level pressure reduction structure.

[0047] Preferably, the diameter of the cylindrical throttling structure decreases from the valve core inlet to the outlet.

[0048] Preferably, the cylindrical throttling structure is the largest at the inlet, and a large change in flow direction will occur when the high-pressure fluid passes through, resulting in increased energy dissipation. This design optimizes the flow rate control effect, and since the pressure at this location is much higher than the saturated steam pressure, there is no need to worry about cavitation.

[0049] Preferably, the diameter of the cylindrical throttling structure gradually decreases and the size of the fluid channel gradually increases. During the flow process, there will be no increase in flow velocity due to the contraction of the flow channel size, thereby achieving better control of the flow velocity and improving the mass flow rate.

[0050] Preferably, the cylindrical throttling structures in the last two stages of the cylinder are replaced with streamlined structures, which not only improves the uniformity of the flow field, but also reduces the size of the low-pressure area in the wake of the cylindrical throttling structure, prevents severe cavitation caused by excessively low local pressure, and reduces the cavitation rate at the fluid outlet.

[0051] Preferably, the present invention can adjust the number of array structures according to flow demand. If the expected value cannot be reached, the number of circumferential arrays can be continuously increased until the valve core disc is filled.

[0052] The design method of the novel valve core flow channel structure of the present invention is implemented by using a specific algorithm, and the algorithm content includes:

[0053] The angle level n is calculated based on the pressure difference between the upstream and downstream of the labyrinth regulating valve. c After that, according to n c The cylindrical throttling structure level n is calculated. The cylindrical throttling structure level n of the valve core flow channel of the present invention is calculated in the following way:

[0054]

[0055] This is because each level of cylindrical throttling structure provides two corner throttling effects, so the number of cylinders is half of the number of calculated corner levels.

[0056] The first-stage cylindrical throttling structure circumscribed radius S 1 , calculated as follows:

[0057]

[0058] Where: Δx represents the distance coefficient, which is the distance between the inscribed radius of the previous throttling structure and the circumscribed radius of the next throttling structure, 0.5mm≤Δx≤2mm; L represents the outer diameter of the valve core, which is usually determined by the valve design size.

[0059] The innermost inscribed radius S of the final throttling structure n , calculated as follows:

[0060]

[0061] Where: l is the inner diameter of the valve core, which is usually determined by the valve design size.

[0062] Starting from the outermost side, the size of the first-stage cylindrical throttling structure is determined by the following formula:

[0063]

[0064] Where: R 1 Indicates the radius of the first-stage cylindrical throttling structure; w 1 Indicates the flow channel width when the fluid flows through the first-stage cylindrical throttling structure.

[0065] w 1 The recommended value range is 3mm≤w 1 ≤10mm, this width can be adjusted according to the maximum and minimum sizes of the valve core. 1 When w decreases, the resistance generated by throttling increases, thereby better meeting the flow rate control requirements under high pressure difference conditions and reducing the flow rate; on the contrary, when w 1 When it increases, the resistance generated by throttling decreases, making it difficult to meet the flow rate control requirements under high pressure difference conditions and resulting in a larger flow rate.

[0066] α represents the included angle between two rows of throttling structures, and it is recommended that 5°≤α≤15°. The larger the angle, the larger the space required for arranging the throttling structure, thereby achieving a better flow rate control effect; conversely, the smaller the angle, the smaller the space required for the structure arrangement, resulting in a relatively general flow rate control effect.

[0067] The circumscribed radius S of the i-th level (1<i≤n) cylindrical throttling structure i , calculated as follows:

[0068] S i =S i-1 -2R i-1 -k(i-1)·Δx

[0069] Where: k represents the fluid gap expansion coefficient, and it is recommended that 1≤k≤1.5. Too large a value will affect the fluid control effect, or it should be consistent with the flow channel expansion coefficient when performing series calculation;

[0070] The size of the i-th stage cylindrical throttling structure is determined by the following formula:

[0071]

[0072] Where: R i represents the radius of the i-th cylindrical throttling structure; w i It represents the flow channel width when the fluid flows through the i-th cylindrical throttling structure. The flow channel width is determined by theoretical calculation and can be expanded at each stage according to demand.

[0073] Preferably, after completing the positioning of the cylindrical throttling size of each level, the cylindrical throttling structures of the last two levels need to be replaced with streamlined spoiler structures.

[0074] Preferably, the windward surface of the spoiler structure is the same as the cylindrical throttling structure, and the windward surface is tangent to an eccentric cylindrical section whose diameter is twice that of the cylindrical structure of this level. Finally, the eccentric section is tangent to the tail through a straight line of 15°≤β≤50°, that is, the tail angle of the streamline structure is β.

[0075] Preferably: this streamline structure can achieve better uniformity and significantly reduce the cavitation rate. When the valve inlet pressure is 4MPa and the outlet pressure is normal pressure, the labyrinth flow channel using the structure of the present invention is compared with the existing labyrinth flow channel, and the average cavitation rate of the outlet cross section is reduced from 75.8% to 41.9%.

[0076] Preferably, the radial dimension of the flow-disturbing structure along the valve core disc is less than 2.5 times the dimension of the cylindrical throttling structure of the same level.

[0077] Preferably, the throttling structure is in the form of not completely penetrating the valve core disc, and a plurality of cylindrical and streamlined convex structures are formed on the inner side of the valve core disc. Figure 2 As shown, a plurality of groups of groove structures are arranged on the inner side of the valve core disc, and cylindrical and streamlined convex block structures are arranged in each group of groove structures, and the convex block structures are distributed in an array.

[0078] Preferably, after completing the above-mentioned size calculation, it is necessary to check whether the overall flow channel structure size can be completely arranged on the valve core disc, otherwise it is necessary to readjust the size of the flow channel throttling original part, and the calculation method is as follows:

[0079] D=S 1 -S n

[0080] In the formula, D represents the maximum radial arrangement size of the valve core disc;

[0081] The judgment formula is:

[0082]

[0083] If the result of this formula is true, it proves that the labyrinth flow channel structure can be arranged on the valve core disc currently designed, and the structure is available;

[0084] If the result of this formula is false, it proves that the labyrinth flow channel structure cannot be arranged on the currently designed valve core disc, and local details need to be readjusted.

[0085] In some embodiments of the present invention, the design method of the novel valve core flow channel structure of the present invention is shown in Figure 1 As shown, the steps include:

[0086] Step 1, obtain the distance coefficient Δx, the valve core outer diameter L and the valve core inner diameter l, and the expansion coefficient k;

[0087] Calculate the first-stage cylindrical throttling structure circumscribed radius S according to the distance coefficient Δx and the valve core outer diameter L 1 ;

[0088] The innermost inscribed radius S of the final throttling structure is calculated based on the distance coefficient Δx and the inner diameter l of the valve core. n ;

[0089] According to the number of rotation angles n c Calculate the number of cylindrical throttling structures n in the valve core flow channel;

[0090] Step 2: Determine the first-stage flow channel width w 1 ;

[0091] Step 3: Determine the angle α between the two rows of throttling structures, such as Figure 3 As shown in , the centers of all the cylinders in each row of throttling structures are coaxial, and the diameters of the cylinders decrease from the valve core inlet to the valve core outlet;

[0092] Step 4: According to the circumscribed radius S of the first-stage cylindrical throttling structure 1 、Width of first-stage flow channel w 1 The radius R of the first-stage cylindrical throttling structure is calculated by the angle α of the throttling structure 1 ;

[0093] Step 5: Calculate the circumscribed radius S of the cylinder in the i-th level throttling structure i , the radius R of the cylinder in the i-th throttling structure i , 1<i≤n;

[0094] According to the circumscribed radius S of the cylinder in the i-1th level throttling structure i-1 , the radius R of the cylinder in the i-1th level throttling structure i-1 , distance coefficient Δx and expansion coefficient k to calculate the circumscribed radius S of the cylinder in the i-th level throttling structure i ;

[0095] According to the circumscribed radius S of the cylinder in the i-th level throttling structure i 、Width w of the i-th flow channel i , the throttling structure angle α, the distance coefficient Δx and the expansion coefficient k are used to calculate the radius R of the cylinder in the i-th throttling structure. i ;

[0096] Step 6: Determine whether the flow channel structure currently designed can be arranged on the current valve core;

[0097] The way to judge is by size;

[0098] Calculate the maximum radial arrangement dimension D of the valve core and the outer diameter dimension H of the flow channel structure;

[0099] Determine whether D is greater than or equal to H. If so, it means that the currently designed flow channel structure can be arranged on the current valve core; otherwise, it means that the currently designed flow channel structure cannot be arranged on the current valve core, and return to step 1 for redesign.

[0100] Embodiment 1:

[0101] The flow channel structure is calculated based on the upstream and downstream pressure difference conditions with an inlet pressure of 4MPa and an outlet pressure of normal pressure. The valve core flow channel throttling level is 7, and the flow channel inlet width is w 1 is 6mm, the flow channel expansion coefficient k is 1.05, the flow channel distance coefficient Δx is 0.5mm, and the calculated disc shape is as follows Figure 2 As shown, the specific structure is as follows:

[0102] The diameter of the cylindrical throttling structure decreases from the valve core inlet to the outlet; the cylindrical throttling structure is largest at the inlet, and a large change in flow direction occurs when the high-pressure fluid passes through, resulting in increased energy dissipation; from the valve core inlet to the outlet, the diameter of the cylindrical throttling structure gradually decreases, and the size of the fluid channel gradually increases.

[0103] This design optimizes the flow rate control effect and improves the flow capacity of the valve core. Under the conditions of an inlet pressure of 4MPa and an outlet pressure of normal pressure, the maximum flow rate in the flow channel is less than 85m / s, and the mass flow rate of a single flow channel is 1.31kg / s.

[0104] The throttling structure of the last two stages of the cylinder is replaced with a streamlined structure, which improves the uniformity of the flow field and prevents severe cavitation caused by low local pressure.

[0105] The cylindrical throttling structure and the streamlined throttling structure are arranged on the valve core disc in an array manner. Figure 2 The number of multi-strand structures can affect the flow rate, but has no essential effect on the actual pressure reduction process in the flow field, so the flow rate can be increased by increasing the number of arrays.

[0106] Design the dimensions of the valve core flow channel structure. The specific calculation contents include:

[0107] Calculate the required pressure reduction level n according to the actual use of the valve c Afterwards, the number of stages n required for the cylindrical throttling structure required for the flow channel of this embodiment is calculated according to the following formula.

[0108]

[0109] If you are modifying an existing valve, you need to input the existing valve core outer diameter L and inner diameter l; if you are designing a new valve structure, input the valve core outer diameter L and inner diameter l according to the design requirements.

[0110] Enter the required valve core distance coefficient Δx, which is the distance between the inscribed radius of the previous throttling structure and the circumscribed radius of the next throttling structure. Figure 3 , it is recommended that 0.5mm≤Δx≤2mm. If it is too large, it will affect the flow rate control effect of the flow channel.

[0111] Enter the fluid gap expansion coefficient k. It is recommended that 1≤k≤1.5. A too large value will affect the fluid control effect. It should be consistent with the flow channel expansion coefficient when performing series calculation.

[0112] Calculate the circumscribed radius S of the first-stage cylindrical throttling structure based on the input data 1 , the specific calculation method is as follows:

[0113]

[0114] Calculate the inscribed radius S of the last stage throttling structure according to the input data n , the specific calculation method is as follows:

[0115]

[0116] The flow channel width w of the input fluid when it flows through the first-stage cylindrical throttling structure 1 , usually the flow channel of the labyrinth valve is small. If there is no special regulation, it is recommended to be 3mm≤w 1 ≤10mm, this width can be adjusted according to the maximum and minimum sizes of the valve core. 1 When w decreases, the resistance generated by throttling increases, thereby better meeting the flow rate control requirements under high pressure difference conditions and reducing the flow rate; on the contrary, when w 1 When it increases, the resistance generated by throttling decreases, making it difficult to meet the flow rate control requirements under high pressure difference conditions and resulting in a larger flow rate.

[0117] Input the throttling structure angle α, it is recommended to be 5°≤α≤15°. The larger the angle, the larger the space required for arranging the throttling structure, thereby achieving a better flow rate control effect; conversely, the smaller the angle, the smaller the space required for the structure arrangement, resulting in a relatively general flow rate control effect.

[0118] First, the radius of the first-stage cylindrical structure of the throttling structure needs to be determined according to the input data, as shown in the following formula:

[0119]

[0120] Secondly, the size of the subsequent structure is calculated based on the first-level structure, as follows:

[0121] The circumscribed radius S of the cylinder in the i-th level (1<i≤n) throttling structure i , calculated as follows:

[0122] S i =S i-1 -2R i-1 -k(i-1)·Δx

[0123] The radius R of the cylinder in the i-th stage throttling structure i Determined by the following formula:

[0124]

[0125] Finally, the structure of the last two stages needs to be changed to a streamlined structure based on the cylindrical throttling structure, and the overall flow channel structure size needs to be checked to see whether it can be fully arranged on the valve core disc, as follows:

[0126] Changes to the streamlined spoiler structure, and suggestions for the labyrinth flow channel streamlined spoiler structure Figure 4 As shown:

[0127] First, the windward surface of the spoiler structure is the same as the cylindrical throttling structure;

[0128] Secondly, the windward surface is tangent to an eccentric circular surface whose diameter is twice that of the cylindrical structure;

[0129] Finally, the eccentric section is tangent to the straight line with an angle of 15°≤β≤50°.

[0130] Verification of flow channel structure dimensions:

[0131] It is necessary to check whether the overall flow channel structure size can be completely arranged on the valve core disc. Otherwise, it is necessary to readjust the size of the flow channel throttling original. The calculation method is as follows:

[0132] D=S 1 -S n

[0133] Where: D represents the maximum radial arrangement size of the valve core disc;

[0134] determination:

[0135]

[0136] If the result of the above formula is true, it proves that the labyrinth flow channel structure can be arranged on the currently designed valve core disc and the structure is available; if the result of the above formula is false, it proves that the labyrinth flow channel structure cannot be arranged on the currently designed valve core disc, and the structural parameters of the flow channel input need to be readjusted and calculated again.

[0137] See also Figure 5 As shown, compared with other flow channel types, the structure of the present invention significantly reduces the cavitation rate of the fluid outlet. The average cavitation rate of the outlet cross section is reduced from 75.8% to 41.9%, and the maximum cavitation rate in the flow channel is reduced from more than 95% to 65%.

[0138] The present invention can adjust the number of array structures according to flow requirements. If the expected value cannot be reached, the number of circumferential arrays can be continuously increased until the valve core disc is filled. The flow channel structure of this embodiment only occupies half of the area of ​​the valve core disc, and the flow channels can continue to be increased to further increase the flow capacity of the valve core.

[0139] For the parts of the present invention not described in detail, please refer to the prior art in the art or know the technology well known to those skilled in the art.

[0140] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A new valve core flow channel structure of a labyrinth regulating valve, characterized in that: The valve core flow channel structure includes a plurality of pressure reducing structures arranged in sequence from the valve core inlet to the valve core outlet, and the diameter of the pressure reducing structure decreases in sequence from the valve core inlet to the valve core outlet; Several stages of pressure reduction structures starting from the valve core inlet adopt cylindrical throttling structures; several stages of pressure reduction structures close to the valve core outlet adopt streamlined throttling structures; both the cylindrical throttling structures and the streamlined throttling structures are arranged in an array on the valve core disc.

2. The novel valve core flow channel structure of the labyrinth regulating valve according to claim 1 is characterized in that: The streamlined throttling structure includes a cylinder and two veneer shapes; the cylinder is located in the middle, and the two veneer shapes are arranged on both sides of the cylinder; one end of any veneer shape is tangentially connected to the edge of the cylinder, and the other end is connected to the non-cylindrical connecting end of another tangent shape.

3. The novel valve core flow channel structure of the labyrinth regulating valve according to claim 2 is characterized in that: The veneer shape is an eccentric circular surface whose diameter is twice the diameter of the cylinder.

4. The novel valve core flow channel structure of the labyrinth regulating valve according to claim 1 is characterized in that: The diameter of the cylindrical throttling structure decreases from the valve core inlet to the valve core outlet.

5. The novel valve core flow channel structure of the labyrinth regulating valve according to claim 3 is characterized in that: The diameter of the cylinder of the streamlined throttling structure decreases from the valve core inlet to the valve core outlet.

6. The novel valve core flow channel structure of the labyrinth regulating valve according to claim 1 is characterized in that: The value range of the throttling structure angle α is 5°≤α≤15°.

7. A design method for a novel valve core flow channel structure of a labyrinth regulating valve according to any one of claims 1 to 6, characterized in that: The steps of the method include: S1, obtain the distance coefficient Δx, the valve core outer diameter L, the valve core inner diameter l and the expansion coefficient k, and calculate the circumscribed radius S1 of the first-stage cylindrical throttling structure and the innermost inscribed radius S of the final-stage throttling structure based on the obtained data n , the number of throttling structures n in the valve core flow channel; S2, determining the first-stage flow channel width w1; S3, determine the cylindrical throttling structure angle α; S4, calculating the radius R1 of the first-stage cylindrical throttling structure according to the circumscribed radius S1 of the first-stage cylindrical throttling structure, the first-stage flow channel width w1 and the cylindrical throttling structure angle α; S5. Calculate the circumscribed radius S of the i-th level throttling structure i , the radius R of the i-th throttling structure i , 1<i≤n; when the throttling structure is a cylindrical throttling structure, the radius R i is the radius of the cylinder in the throttling structure, and the circumscribed radius S i is the circumscribed radius of the cylinder in the throttling structure; when the throttling structure is a streamlined throttling structure, the radius R i is the radius of the cylinder in the streamlined throttling structure, and the circumscribed radius S i is the circumscribed radius of the cylinder in the streamlined throttling structure; S6. Determine whether the flow channel structure currently designed can be arranged on the current valve core by size; if not, return to S1.

8. The novel valve core flow channel structure and design method of the labyrinth regulating valve according to claim 7 is characterized in that: In step S1: The circumscribed radius S1 of the first-stage cylindrical throttling structure is calculated according to the distance coefficient Δx and the valve core outer diameter L; The innermost inscribed radius S of the final throttling structure is calculated based on the distance coefficient Δx and the inner diameter l of the valve core. n ; According to the number of rotation angles n c Calculate the number n of cylindrical throttling structures in the valve core flow channel.

9. The novel valve core flow channel structure and design method of the labyrinth regulating valve according to claim 7 is characterized in that: In step S5: According to the circumscribed radius S of the i-1th cylindrical throttling structure i-1 , the radius R of the i-1th cylindrical throttling structure i-1 , distance coefficient Δx and expansion coefficient k to calculate the circumscribed radius S of the i-th cylindrical throttling structure i ; According to the circumscribed radius S of the i-th cylindrical throttling structure i 、Width w of the i-th flow channel i , the cylindrical throttling structure angle α, the distance coefficient Δx and the expansion coefficient k are used to calculate the radius R of the i-th cylindrical throttling structure i .

10. The novel valve core flow channel structure and design method of a labyrinth regulating valve according to claim 7, characterized in that: The contents determined by size in step S6 include: Calculate the maximum radial arrangement dimension D of the valve core and the outer diameter dimension H of the flow channel structure; Determine whether D≥H holds true; if so, it means that the currently designed flow channel structure can be arranged on the current valve core, and the design is completed; otherwise, it means that the currently designed flow channel structure cannot be arranged on the current valve core, and return to step 1 for redesign.

Images