Self-cooling butt-assembled integral impeller

Abstract

When an outer shaft structure is adopted, an inner duct fan blade and an outer duct fan blade form a whole through a rotary drum, a spiral fan blade without a central shaft is used in an inner duct and fixed to the inner wall of the rotary drum in a symmetrical splicing installation (butt installation) mode, a plate-shaped reinforcing structure is used in a spiral inner cavity, and the spiral inner cavity is communicated with the outer duct through air holes in the wall of the rotary drum. The outer duct semicircular integral impeller pair is arranged at the periphery of the rotary drum; when the inner shaft structure is adopted, spiral fan blades with a central shaft are used and fixed to a rotating shaft and a power spiral in a butt-mounting mode, the rotating shaft is hollow and two ends of the rotating shaft are closed, an air inlet hole is reserved in an air compression end of the rotating shaft, an air hole is reserved in a first blade spiral fixing position of a power end, and a cooling channel is formed along the interior of the spiral and is discharged from the tail end; a double-helix or multi-helix structure is formed in a butt-assembling mode and is prolonged according to needs, efficient cooling can be achieved through a cavity structure, heat efficiency can be directly improved through an outer shaft structure, and the butt-assembling mode has high efficiency and reliability of an integral impeller while cost and process requirements are reduced.

Description

Technical Field

[0001] The invention relates to a self-cooling paired integral impeller. Background Art

[0002] The most direct way to improve the power and efficiency of a gas turbine is to increase the core combustion temperature, that is, the turbine pre-temperature. However, excessively high temperatures can cause failure and damage to the heated materials. When material properties develop relatively slowly, cooling technology can effectively increase the material's operating temperature.

[0003] At present, turbine blade cooling technology is mainly divided into two methods: internal cooling and external cooling. In internal cooling, the cooling airflow and the combustion airflow do not interfere with each other, but good cooling air ducts and air volume are required to achieve better results. Due to the limitations of the internal space and processing technology of the internal blades, the development of internal cooling is relatively slow or even stagnant; while in external cooling (film cooling), the cooling airflow and the combustion airflow have an interactive area, and a relatively complex aerodynamic model needs to be considered during the design, and the cost and process requirements are also high.

[0004] The current fan blade cooling technology is basically aimed at improving system performance and reliability, and generally has little effect on improving thermal efficiency.

[0005] Compared with traditional assembled impellers, integral impellers have higher efficiency and reliability and are an important trend for future development. Summary of the invention

[0006] In order to solve the problems of cooling high-temperature fan blades, simplifying the manufacturing and maintenance process, and recycling heat energy, the present invention discloses a self-cooling paired integral impeller. When an external shaft structure is adopted, the inner and outer duct blades are formed as a whole through a rotating drum, the inner duct uses a spiral fan blade without a central axis, which is fixed to the inner wall of the rotating drum by a symmetrical splicing installation (pair installation), and the spiral inner cavity uses a plate-shaped reinforcement structure, which is interconnected with the outer duct through the air holes on the rotating drum wall, and the outer duct semicircular integral impeller is paired to the periphery of the rotating drum; when an inner shaft structure is adopted, a spiral fan blade with a central axis is used, which is fixed to the rotating shaft in a pair installation manner, the power spiral is hollow, the rotating shaft is hollow and closed at both ends, the rotating shaft reserves an air inlet hole at the low-temperature compression end, and reserves an air hole at the fixed position of the first blade spiral at the power end, and a cooling channel is formed along the spiral and discharged from the tail end; a double helix or multi-helix structure is formed by a pair installation method and extended as needed, the cavity structure can achieve efficient cooling, and the thermal efficiency can be directly improved under the external shaft structure. The pair installation method has the high efficiency and reliability of the integral impeller while reducing costs and process requirements.

[0007] When using the external axis structure, the inner-channel fan blade is in the shape of an Archimedean spiral with the optimized feature of having no central axis. It is connected to the rotating drum through an external axis. A reinforcing rib plate is arranged axially inside the spiral fan blade. A certain interval is left between the reinforcing rib plate and the tip of the spiral fan blade to form a cooling air flow channel. The reinforcing rib plate drives the air inside the fan blade to form a powerful cooling air flow during rotation, which acts as a cooling blade inside the fan blade. The inner-channel spiral fan blade unit is extended and expanded through a symmetrical splicing installation method.

[0008] When using the external shaft structure, the outer duct uses a symmetrically spliced ​​integral impeller, which reduces the complexity of installation and maintenance of the outer duct fan blades while maintaining the high efficiency and reliability of the integral impeller. Compared with an integrated impeller, the symmetrically spliced ​​integral impeller is more adaptable to complex installation environments and is easier to maintain and replace. Compared with a single-piece assembly method, the symmetrically spliced ​​integral impeller has better efficiency and reliability, and can also better reduce the total weight.

[0009] When using the external shaft structure, holes are reserved along the inner channel spiral blade fixed positions of the rotating drum to ensure smooth exchange of cooling air flow of the inner channel fan blades; compared with grooving or overall hollowing, drilling can greatly reduce the impact on the overall strength of the equipment.

[0010] When using the external shaft structure, the cooling airflow in the inner cavity of the spiral fan blade in the inner duct is directly connected to the outer duct, and the airflow in the outer duct flows back to the inner duct, directly realizing the recovery of heat energy and the improvement of thermal efficiency.

[0011] When using the inner shaft structure, the power turbine adopts spiral blades with a central axis. The blades are Archimedean spiral-shaped, and the radial cross-section of the power spiral is V-shaped and hollow. The first radial end face of the first blade power spiral is closed along the airflow direction. The cooling airflow enters from the fixed position of the first blade spiral blade shaft, forming a through cooling airflow channel inside the power spiral and discharged from the tail end spiral to achieve efficient cooling.

[0012] When using the inner shaft structure, the shaft is hollow and closed at both ends. An air inlet hole is reserved at the low-temperature compression end of the shaft, and an air hole is reserved at the fixed position of the first blade spiral at the power end to realize an independent cooling channel for low-temperature compressed air. While providing cooling airflow for the power spiral, the shaft itself is also cooled at the same time.

[0013] When the inner shaft structure is used, the turbine at the air compression end adopts spiral blades with a central axis. The blades are in the shape of an Archimedean spiral. Since the operating temperature at the air compression end is relatively low, the blades use a solid structure and can be fixed to the rotating shaft by a pair-mounting method. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Attached Figure 1 The present invention is a front cross-sectional view of the outer shaft structure of a self-cooling paired integral impeller.

[0015] Attached Figure 2 It is a three-dimensional schematic diagram of the outer shaft structure of a self-cooling paired integral impeller of the present invention.

[0016] Attached Figure 3 It is a three-dimensional schematic diagram of a basic unit of spiral blades inside an outer shaft structure of a self-cooling paired integral impeller of the present invention.

[0017] Attached Figure 4 This is a wireframe diagram of the basic unit of the spiral blades inside the outer shaft structure of a self-cooling integral impeller of the present invention.

[0018] Attached Figure 5 This is a wireframe diagram of the basic unit assembly of spiral blades inside the outer shaft structure of a self-cooling integral impeller of the present invention.

[0019] Attached Figure 6 It is a three-dimensional schematic diagram of the assembly of the outer shaft structure and the inner channel fan blades of a self-cooling paired integral impeller of the present invention.

[0020] Attached Figure 7 It is a three-dimensional schematic diagram of an outer duct blade unit of an outer shaft structure of a self-cooling paired integral impeller of the present invention.

[0021] Attached Figure 8 It is a three-dimensional schematic diagram of the heat dissipation holes of the outer shaft structure of the rotating drum of a self-cooling paired integral impeller of the present invention.

[0022] Attached Fig. 9 The present invention is a front view of the inner shaft structure of a self-cooling paired integral impeller. DETAILED DESCRIPTION

[0023] Attached Figure 1 -Attached Figure 8 A first embodiment of the present invention is shown. Fig. 9 A second embodiment of the present invention is shown. It should be noted that these and subsequent drawings are only examples and are not drawn in proportion. The drawings only show the parts related to the present invention rather than all structural processes, and should not be used as a limitation on the actual scope of protection required by the present invention.

[0024] Attached Figure 1 It is a front view cross-sectional view of embodiment 1 of the present invention, and the numbers in the figure respectively represent: 1. inner duct spiral blade; 2. outer duct blade; 3. outer duct blade mounting hole; 4. rotor heat dissipation hole; 5. rotor sealing head; 6. engine frame diagram.

[0025] The inner spiral blade of embodiment 1 is composed of blade basic units in a pair-mounted manner (such as the attached Figure 5 As shown), it is a symmetrical structure along the radial direction of the central axis.

[0026] The inner channel spiral blades of Example 1 can be directly welded to the inner wall of the drum, and can also be fixed by screws on the outer wall of the drum. In order to strengthen the isolation of high-temperature combustion gas and cooling air, high-temperature sealants (such as graphite) can be used for sealing. In order to improve the heat resistance of the system, the inner wall of the drum and the inner channel blade surfaces can be sprayed with heat-resistant materials (such as silicon carbide or silicon nitride).

[0027] The outer duct fan blades of Example 1 adopt a semicircular integral impeller method. The two semicircular integral impellers are completely identical in structure and are installed in a symmetrical splicing manner. During installation, ensure that the blade directions of the two semicircular integral impellers are consistent; bolts and nuts are used for tightening during installation; the number of outer duct fan blade groups can be increased or decreased as required, but the fan blade groups must be spaced a certain distance apart to prevent blocking the heat dissipation holes on the drum.

[0028] The rotating drum of Example 1 is provided with a heat dissipation hole group along the hollow position of the inner spiral blade, the opening direction of the heat dissipation hole is perpendicular to the central axis, and the heat dissipation hole position is kept at an appropriate distance from the edge of the inner spiral blade.

[0029] Example 2 uses an inner shaft structure, in which the central shaft is a hollow rotating shaft with both ends closed. The left end along the direction of airflow is the low-temperature air compression end, and the right end is the power turbine end. The rotating shaft has an air inlet reserved near the low-temperature air compression end, and an air outlet is reserved at the fixed position of the first blade spiral fan blade at the power end.

[0030] Example 2 uses an inner shaft structure, and the power spiral is characterized by an Archimedean spiral blade with a central axis. The inner cavity is a V-shaped hollow structure without a partition. The first radial end face of the first blade power spiral is closed along the airflow direction, and its subsequent power spiral blades are V-shaped through-type hollow blades. The power spiral is fixed to the rotating shaft in a pair-mounted manner to form a double helix or multi-helix structure.

[0031] Embodiment 2 uses an inner shaft structure, the turbine at the air compression end is an Archimedean screw blade with a central axis, the blade uses a solid plate structure, and the air compression spiral is fixed to the rotating shaft by a pair-mounting method to form a double spiral or multi-spiral structure.

[0032] The specific embodiments described above further illustrate the purpose, technical solutions and effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A self-cooling paired integral impeller, characterized in that: An external shaft structure is adopted, and the inner and outer duct fan blades are integrated through the rotor. The inner duct adopts spiral fan blades without a central axis, which are fixed to the inner wall of the rotor by symmetrical splicing installation (pair installation). The spiral inner cavity uses a plate-like reinforcement structure, which is interconnected with the outer duct through the air holes on the rotor wall. The semi-circular integral impeller of the outer duct is pair-mounted to the periphery of the rotor; a double-helix or multi-helix structure is formed by pair installation and can be extended as needed.

2. A self-cooling paired integral impeller, characterized in that: It adopts an inner shaft structure and uses spiral fan blades with a central shaft, which are fixed to the rotating shaft in a pair-mounted manner. The power spiral is hollow, and the rotating shaft is hollow and closed at both ends. The rotating shaft has an air inlet hole reserved at the low-temperature compression end, and an air hole reserved at the fixed position of the first blade spiral at the power end. A cooling channel is formed along the inside of the spiral and discharged from the tail end; a double or multi-spiral structure is formed by a pair-mounted manner and can be extended as needed.

3. The self-cooling paired integral impeller according to claim 1, characterized in that: The inner channel fan blade is in the shape of an Archimedean spiral, with the optimized feature of having no central axis, connected to the rotor through an open end, and the axial feature of which is complete airflow blocking; the inner channel fan blade is installed by welding or by fastening with screws on the outside of the rotor.

4. The self-cooling paired integral impeller according to claim 1, characterized in that: The inner spiral blades can select an integer multiple of 90 degrees as the radial angle range of the basic blade unit, preferably 180 degrees; the spiral blades divide the circumferential angle equally along the radial direction and extend to form a multi-helix structure, such as 2 spiral blades are symmetrically distributed along the radial direction of 180 degrees and extended to form a double helix structure, 3 spiral blades are equally distributed along the radial direction of 120 degrees and extended to form a triple helix structure, and the total number in the axial direction is an integer multiple of the complete blades.

5. The self-cooling paired integral impeller according to claim 1, characterized in that: The pitch of the inner spiral fan blades needs to be adjusted according to the diameter of the rotor, and factors such as the volume and velocity of the combustion airflow are taken into consideration. The pitch can be equal to or proportional to the radial area of ​​the rotor through the area, or a variable pitch can be used according to the change of the airflow velocity.

6. The self-cooling paired integral impeller according to claim 1, characterized in that: The interior of the inner spiral blade is a V-shaped hollow structure, and its angle can be optimized and adjusted according to the airflow velocity, including the radial angle of the impact surface and the size of the internal angle. Generally, the radial angle range of the impact surface is 0-30 degrees, and the internal angle range is 5-30 degrees.

7. The self-cooling paired integral impeller according to claim 1, characterized in that: The reinforcing ribs set inside the inner spiral blades are parallel to the axis of the drum and evenly distributed at an angle. A certain distance is reserved between the ribs and the tip of the blade (towards the center of the drum) to form a cooling air flow exchange channel and enhance the cooling effect of the tip of the blade.

8. The self-cooling paired integral impeller according to claim 1, characterized in that: Ventilation holes are opened along the inner channel blade opening position (along the spiral line) of the drum. The direction of the ventilation holes is perpendicular to the axis of the drum. The diameter and number of the ventilation holes can be adjusted according to the material and processing technology, and the total ventilation area (the product of the unit area and the number of ventilation holes) should be increased as much as possible.

9. The self-cooling paired integral impeller according to claim 1, characterized in that: The outer duct fan blades use a semicircular integral impeller as the basic unit, adopt a semicircular symmetrical splicing installation method, and are fastened with bolts and nuts. The number of outer duct fan blades can be adjusted according to the air flow and static pressure requirements, and their installation position should minimize obstruction to the rotor vents.

10. The self-cooling paired integral impeller according to claim 2, characterized in that: The power turbine blades are in the shape of an Archimedean spiral, the first power spiral blade is closed on the first radial end face along the airflow direction, and the subsequent power spiral blades are V-shaped through-type hollow blades.

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