Flow control method based on porous coating and impeller blade with flow control method

Abstract

The invention relates to a flow control method based on a porous coating and an impeller blade with the porous coating, the blade is provided with a porous elastic polymer flow self-adaptive coating, and the porous elastic polymer flow self-adaptive coating is used for reducing the pressure of the porous elastic polymer flow self-adaptive coating under the working condition that the flow is smaller than the designed flow. The surface roughness of the coating position of the blade is increased to promote full mixing of a flowing boundary layer on the surface of the blade, so that flowing separation is avoided; under the working condition that the flow is larger than the designed flow, the pressure borne by the porous elastic polymer self-adaptive coating is increased, the surface roughness of the coating position of the blade is reduced, and therefore the flow resistance of the coating position of the surface of the blade is reduced. The performance of the impeller under the non-design working condition can be improved by coating the porous elastic polymer flow self-adaptive coating, so that the working range of the impeller is widened.

Description

Technical Field

[0001] The present invention belongs to the technical field of fluid machinery, and in particular relates to a flow control method based on a porous coating and an impeller blade having the same. Background Art

[0002] As one of the most common general-purpose equipment in various industrial scenarios, fluid machinery plays an irreplaceable and important role in the fields of power generation and power. Classical fluid machinery design methods often only consider parameters under a single design condition. Although existing methods can achieve relatively good fluid machinery performance under design conditions, the problem of performance degradation under non-design conditions is still prominent, which seriously restricts the operating performance of fluid machinery equipment under complex and changeable conditions.

[0003] Improving and enhancing the performance of fluid machinery within a relatively wide range of non-design operating conditions is an important direction for the current development of fluid machinery. Using simple transformation methods to improve the components of fluid machinery to enhance their adaptability to complex working conditions can greatly reduce resource loss and help achieve the goal of carbon neutrality as soon as possible. It can be seen that improving the performance of fluid machinery within a wide range of operating conditions has important engineering value for enriching application scenarios and reducing energy consumption. Summary of the invention

[0004] The object of the present invention is to provide a flow control method based on a porous coating and an impeller blade having the same, so as to improve the performance of the impeller under non-design conditions and broaden its working range.

[0005] The present invention provides a flow control method based on a porous coating and an impeller blade having the same, wherein the blade has a porous elastic polymer flow adaptive coating, and the porous elastic polymer flow adaptive coating is used for:

[0006] Under the condition of less than the design flow rate, the porous elastic polymer adaptive coating is subjected to reduced pressure, and the surface roughness of the blade coating position is increased to promote full mixing of the flow boundary layer on the blade surface, thereby avoiding the occurrence of flow separation;

[0007] Under the condition that the flow rate is greater than the design flow rate, the porous elastic polymer adaptive coating is subjected to increased pressure, which reduces the surface roughness of the blade coating position, thereby reducing the flow resistance at the blade surface coating position.

[0008] Furthermore, the blade includes a blade inlet section from the inlet edge to the front one-third position, a blade middle section from the front one-third position to the rear one-third position, and a blade outlet section from the one-third position to the outlet edge along the relative axial streamline; the blade has a blade convex side and a blade concave side, and the blade convex side of the blade inlet section and the blade concave side of the blade outlet section are coated with a porous elastic polymer.

[0009] Furthermore, the porous elastic polymer flow adaptive coating expands along the normal direction of the wall under low pressure, so that the blade surface presents a microporous rough structure, so as to increase the roughness of the coating position on the blade surface.

[0010] Furthermore, the porous elastic polymer flow adaptive coating shrinks along the wall normal under high pressure, so that the blade surface presents a flattened structure, so as to reduce the roughness of the coating position on the blade surface.

[0011] The present invention also provides an impeller, comprising the blades coated with the porous elastic polymer flow adaptive coating.

[0012] By means of the above scheme, through a porous coating-based flow control method and an impeller blade having the same, the impeller can maintain a high performance under non-design conditions, thereby being able to operate stably within a wider working range.

[0013] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic diagram of the structure of a flow control method based on a porous coating and an impeller blade having the same according to the present invention;

[0015] Figure 2 Schematic diagram of the expansion of a porous elastic polymer flow adaptive coating under low pressure in one embodiment of the present invention.

[0016] Figure 3 Schematic diagram of the contraction of a porous elastic polymer flow adaptive coating under high pressure in one embodiment of the present invention.

[0017] Reference numerals:

[0018] 1-blade; 11-blade inlet section; 12-blade middle section; 13-blade outlet section;

[0019] 2-blade inlet edge; 3-blade outlet edge; 4-blade convex side; 5-blade concave side; 6-blade inlet section convex side; 7-blade outlet section concave side; 8-blade surface;

[0020] 91 - porous elastic polymer in normal state; 92 - porous elastic polymer after low-pressure expansion; 93 - porous elastic polymer after high-pressure contraction. DETAILED DESCRIPTION

[0021] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0022] Ginseng Figure 1 As shown, this embodiment provides a flow control method based on a porous coating and an impeller blade having the same, wherein the blade 1 can be divided into a blade inlet section 11 from the blade inlet edge 2 to the front third position, a blade middle section 12 from the front third position to the rear third position, and a blade outlet section 13 from the third position to the blade outlet edge 3 along the relative axial streamline, and the blade has a blade convex side 4 and a blade concave side 5, and the blade convex side 6 of the blade inlet section 11 and the blade concave side 7 of the blade outlet section 13 are coated with a porous elastic polymer. The porous elastic polymer can be thermoplastic polyurethane, which is attached to the blade surface by thermal spraying or compression molding.

[0023] Ginseng Figure 2 As shown, the porous elastic polymer flow adaptive coating 91 can expand along the wall normal under low pressure to become a low-pressure expanded porous elastic polymer 92, so that the blade surface 8 presents a microporous rough structure, thereby increasing the roughness of the coating position on the blade surface.

[0024] Ginseng Figure 3 As shown, the porous elastic polymer flow adaptive coating 91 can shrink along the wall normal under high pressure to become a porous elastic polymer 93 after high pressure shrinkage, so that the blade surface 8 presents a flattened structure, thereby reducing the roughness of the coating position on the blade surface.

[0025] By coating the surface of the impeller blade with a porous elastic polymer adaptive coating, under the condition of less than the design flow rate, due to the reduced pressure on the porous elastic polymer adaptive coating, the surface roughness of the blade coating position can be increased to promote the full mixing of the flow boundary layer on the blade surface, thereby avoiding the occurrence of flow separation; under the condition of greater than the design flow rate, due to the increased pressure on the porous elastic polymer adaptive coating, the surface roughness of the blade coating position can be reduced to reduce the flow resistance at the blade surface coating position. Therefore, the blade based on the porous elastic polymer flow adaptive coating of the present invention can improve the performance of the impeller under non-design conditions, broaden its working range, and is suitable for any type of fluid machinery.

[0026] This embodiment also provides an impeller, which includes the blades coated with the porous elastic polymer flow adaptive coating 1. Based on a similar structure, the beneficial effect of the impeller in the embodiment of the present invention is: improving the performance of the impeller under non-design conditions, thereby widening its working range.

[0027] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the technical principles of the present invention, and these improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. An impeller blade based on a porous coating, characterized in that: The blade has a porous elastic polymer flow adaptive coating, and the porous elastic polymer flow adaptive coating is used to: Under the condition of less than the design flow rate, the porous elastic polymer adaptive coating is subjected to reduced pressure, and the surface roughness of the blade coating position is increased to promote full mixing of the flow boundary layer on the blade surface, thereby avoiding the occurrence of flow separation; Under the condition that the flow rate is greater than the design flow rate, the porous elastic polymer adaptive coating is subjected to increased pressure, which reduces the surface roughness of the blade coating position, thereby reducing the flow resistance at the blade surface coating position.

2. An impeller blade based on a porous coating according to claim 1, characterized in that: The blade (1) comprises a blade inlet section (11) from the blade inlet edge (2) to the front third position, a blade middle section (12) from the front third position to the rear third position, and a blade outlet section (13) from the third position to the blade outlet edge (3) along the relative axial streamline; the blade (1) has a blade convex side (4) and a blade concave side (5); the blade convex side (4) of the blade inlet section (11) and the blade concave side (5) of the blade outlet section (13) are coated with a porous elastic polymer.

3. An impeller blade based on a porous coating according to claim 2, characterized in that: The porous elastic polymer flow adaptive coating expands along the normal direction of the wall under low pressure, so that the blade surface presents a microporous rough structure, so as to increase the roughness of the coating position on the blade surface.

4. An impeller blade based on a porous coating according to claim 3, characterized in that: The porous elastic polymer flow adaptive coating shrinks along the normal direction of the wall under high pressure, so that the blade surface presents a flattened structure, so as to reduce the roughness of the coating position on the blade surface.

5. An impeller, characterized in that: An impeller blade based on a porous coating comprising the impeller blade according to any one of claims 1 to 4.

Images