A cold air flow path structure suitable for a two-bladed turbine disk

Abstract

The application discloses a cold air flow path structure suitable for a double spoke turbine disc, which comprises the double spoke turbine disc, a tenon for being connected with a turbine blade, an annular slot communicated with a disc hub is formed at one end of a disc cavity of the turbine disc close to the disc hub, a plurality of cold air outlet holes communicated with the disc cavity are formed on a disc rim of the turbine disc, a tenon slot matched with the tenon is further formed on the disc rim, the cold air outlet hole is located on the tenon slot, the tenon is installed in the tenon slot, and a gap is left between an inner end of the tenon and a bottom of the tenon slot. Three cooling flow paths are formed through the above structure, namely, the first flow path is formed between the tenon and the tenon slot, the second flow path is formed by sequentially connecting an air inlet hole, the disc cavity, the cold air outlet hole, the gap and a through hole in sequence, and the third flow path is formed by sequentially connecting the slot, the disc cavity, the cold air outlet hole, the gap and the through hole in sequence. The double spoke turbine disc is cooled through the multiple cooling flow paths located at the bottom radius, the middle radius and the high radius, so that the cooling efficiency of the double spoke turbine disc is improved.

Description

Technical Field

[0001] This invention relates to the field of thermal management technology for aero-engines, and more particularly to a cold airflow path structure suitable for a double-spoke turbine disk. Background Technology

[0002] Traditional high-pressure turbine disks employ a single-spoke structure, which is prone to problems such as uneven turbine disk surface temperature and excessive thermal stress. Compared to traditional single-spoke turbine disks, double-spoke turbine disks offer advantages such as reduced disk weight under the same strength conditions, significantly lower turbine disk operating temperature, and effectively improved ANSI efficiencies. 2 With its significant advantages, the US IHPTET program also studies the twin-web turbine disk as a high-performance turbine disk technology. Therefore, some scholars have conducted numerical and experimental studies on the heat transfer characteristics of the twin-web turbine disk cavity. Zhang et al., through a series of multidisciplinary optimization design (MDO) methods such as computational fluid dynamics (CFD), found a twin-web turbine disk structure with the minimum mass that meets the design conditions. They also found that the turbine disk with the twin-web structure exhibits better heat transfer performance than the single-web turbine disk. (ZHANG Meng-chuang, GOU Wen-xuan, LI Lei, et al. Multidisciplinary design and optimization of the twin-webturbine disk[J]. Structural&Multidisciplinary Optimization, 2015, 53(5):1-13.)

[0003] However, with the invention of this new turbine disk structure, corresponding problems have also arisen. The traditional single-spoke plate cold air flow path design is not suitable for the double-spoke plate turbine disk structure. In order to match the structural characteristics of the double-spoke plate turbine disk, a new cold air flow path needs to be designed to fully utilize its heat transfer performance. For the traditional single-spoke plate turbine disk structure, the central intake axial flow or the high-position intake radial flow method is usually adopted. For the double-spoke plate structure, Zhao Xi et al. proposed several cold air arrangement schemes, such as central intake to static cavity + central intake rotating cavity, central intake to static cavity + high-position intake rotating cavity, etc., and conducted comparative analysis using numerical simulation method (Zhao Xi, Xu Guoqiang, Luo Xiang et al. Cold air arrangement scheme of hollow disk of equal weight [J]. Journal of Beijing University of Aeronautics and Astronautics, 2009, 35(05):527-531.DOI:10.13700 / j.bh.1001-5965.2009.05.013.), and proposed a cold air flow path that is more suitable for the double-spoke plate turbine disk. However, how to improve the cooling effect of the turbine disk and how to set up a cooling airflow path that is more suitable for the double-spoke turbine disk remain hot research topics in this field. Summary of the Invention

[0004] Purpose of the invention: To address the above-mentioned shortcomings, this invention provides a cold airflow path structure suitable for double-spoke turbine disks.

[0005] Technical Solution: To solve the above problems, the present invention adopts a cold air flow path structure suitable for a double-spoke turbine disk, including a double-spoke turbine disk and a tenon for connecting with turbine blades. The double-spoke turbine disk includes front and rear spokes of the turbine disk and a hollow annular cavity formed by the front and rear spokes of the turbine disk. An annular slot communicating with the center of the disk is opened at one end of the cavity. Several cold air outlet holes communicating with the cavity are opened on the edge of the double-spoke turbine disk. An air inlet hole communicating with the cavity is opened on the front spoke of the turbine disk near the edge. A mortise matching the tenon is opened on the edge of the double-spoke turbine disk. The cold air outlet hole is located on the mortise. The tenon is installed in the mortise. A gap is left between the inner end of the tenon and the bottom of the mortise. A through hole is opened on the tenon. The through hole, the cold air outlet hole and the gap are interconnected. The two sides of the gap pass through the two sides of the turbine disk to form a first flow path.

[0006] Cooling gas enters the disk cavity through the slot and air inlet, cools the double-spoke turbine disk, and flows out through the through hole after passing through the cold gas outlet hole and the gap; cooling gas also flows in from the first flow path inlet and flows out from the first flow path outlet.

[0007] Furthermore, the through hole and the cold air outlet hole are coaxially arranged to form a cold air outlet channel, which is perpendicularly intersecting the first flow path.

[0008] Furthermore, the air inlet, the disk cavity, the cold air outlet, the gap, and the through hole are sequentially connected to form a second flow path.

[0009] Furthermore, the slot, the cavity, the cold air outlet hole, the gap, and the through hole are connected in sequence to form a third flow path.

[0010] Furthermore, the central axis of the air intake is at an angle of 10°-30° to the rotation axis of the turbine disk.

[0011] Furthermore, the central axis of both the cold air outlet hole and the through hole is perpendicular to the turbine disk rotation axis.

[0012] Furthermore, the radial height of the gap is 10%-60% of the total radial height of the tenon connection structure after the tenon is installed in the mortise.

[0013] Furthermore, the flow rate of the first flow path accounts for 10.0% of the total cold air flow rate, the flow rate of the second flow path accounts for 73.3% of the total cold air flow rate, and the flow rate of the third flow path accounts for 16.7% of the total cold air flow rate.

[0014] Furthermore, the flow rate of the first flow path accounts for 10.0% of the total cold air flow rate, the flow rate of the second flow path accounts for 40% of the total cold air flow rate, and the flow rate of the third flow path accounts for 50% of the total cold air flow rate.

[0015] Furthermore, the flow rate of the first flow path accounts for 10.0% of the total cold air flow rate, the flow rate of the second flow path accounts for 16.7% of the total cold air flow rate, and the flow rate of the third flow path accounts for 73.3% of the total cold air flow rate.

[0016] Beneficial effects: Compared with the prior art, the significant advantage of this invention is that it cools the double-spoke turbine disk by means of multiple cooling flow paths located at the bottom radius, middle radius and high radius, thereby improving the cooling efficiency of the double-spoke turbine disk. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the double-spoke turbine disk in this embodiment;

[0018] Figure 2 This is a schematic diagram of the cold airflow path of the double-spoke turbine disk in this embodiment;

[0019] Figure 3 This is a comparison chart of the cooling air utilization rate under different flow distribution schemes in this embodiment. Detailed Implementation

[0020] like Figure 1 As shown, a cooling airflow path structure suitable for a double-spoke turbine disk in this embodiment includes a double-spoke turbine disk 1 and a tenon 6 for connecting with turbine blades. The double-spoke turbine disk 1 includes front and rear spokes of the turbine disk and a hollow annular cavity 4 formed by the front and rear spokes of the turbine disk. An annular slot 3 communicating with the center of the disk is opened at one end of the cavity 4 near the center of the disk 2. This slot 3 serves as an air inlet for cooling gas. Several cooling gas outlet holes 9 communicating with the cavity 4 are opened on the edge of the double-spoke turbine disk 1. An air inlet hole 5 communicating with the cavity 4 is opened on the front spoke (11) of the turbine disk near the edge of the disk. The central axis of the air inlet hole 5 forms a 20° angle with the rotation axis of the turbine disk. This angle setting can reduce the relative velocity of the cooling gas flowing in the turbine disk and improve the overall cooling effect. The double-spoke turbine disk 1 has a mortise 7 on its edge that matches the tenon 6. The cold air outlet hole 9 is located on the mortise 7. The tenon 6 is installed in the mortise 7. A gap 10 is left between the tenon 6 and the bottom of the mortise 7. The two sides of the gap (10) pass through the two sides of the turbine disk (1) to form a first flow path. Each tenon 6 has a through hole 8. The position of the through hole 8 coincides with the central axis of the cold air outlet hole 9, and the central axes of the two are set perpendicular to the first flow path. The through hole 8, the cold air outlet hole 9 and the gap 10 are interconnected.

[0021] like Figure 2As shown, this invention provides three cooling flow paths for the turbine disk. The first flow path involves cooling gas flowing in from one end of the gap 10 between the tenon 6 and the mortise 7, and flowing out from the other end. This first flow path enhances heat transfer within the gap, reducing the temperature at the junction of the disk rim and the blades. The second flow path involves cooling gas entering the disk cavity 4 through the inlet 5, cooling the double-spoke turbine disk 1, and flowing out through the cold air outlet 9, the gap 10, and the through hole 8. The cold air in the second flow path originates from the sealing cavity upstream of the turbine disk, cooling the portion of the turbine disk near the rim. The third flow path involves cooling gas entering the disk cavity 4 through the slot 3, cooling the double-spoke turbine disk 1, and flowing out through the cold air outlet 9, the gap 10, and the through hole 8. This third flow path passes through the entire turbine disk, thus cooling the entire turbine disk. The turbine disk is cooled in multiple ways through three cooling flow paths located at the bottom radius, middle radius, and high radius, which improves the overall cooling efficiency. At the same time, the cooling gas from the second and third flow paths can further cool the temperature of the turbine blades after flowing out of the through hole 8, further improving the utilization rate of the cooling gas.

[0022] This embodiment conducts simulation experiments on the above structure, employing three different cold air flow distribution schemes to verify the cooling effect. The three different cold air flow distribution schemes are: 1) Flow distribution scheme 1: the first flow path accounts for 10.0% of the total cold air flow, the second flow path accounts for 73.3% of the total cold air flow, and the third flow path accounts for 16.7% of the total cold air flow; 2) Flow distribution scheme 2: the first flow path accounts for 10.0% of the total cold air flow, the second flow path accounts for 40% of the total cold air flow, and the third flow path accounts for 50% of the total cold air flow; 3) Flow distribution scheme 3: the first flow path accounts for 10.0% of the total cold air flow, the second flow path accounts for 16.7% of the total cold air flow, and the third flow path accounts for 73.3% of the total cold air flow.

[0023] Calculate the air conditioning utilization rate using the following formula:

[0024] η=q / m

[0025] Where q is the total wall heat transfer, W / m² 2 m represents the airflow rate, kg / s.

[0026] The results of the three groups of experiments are as follows Figure 3 As shown, compared with the dual-path cooling flow path structure with only the second and third cooling paths, the cooling flow path structure with three cooling paths has a better cooling effect. Specifically, the cooling utilization rate of flow distribution scheme 1 is increased by 21.69%, the cooling utilization rate of flow distribution scheme 2 is increased by 21.80%, and the cooling utilization rate of flow distribution scheme 3 is increased by 37.29%.

[0027] The results above show that flow distribution scheme 3 is the most effective in improving the cooling efficiency of the turbine disk. However, each of the three cooling methods has its advantages and disadvantages, mainly in terms of the temperature distribution of the turbine disk. With flow distribution scheme 1, more cooling air is used for cooling the high-radius area, resulting in a lower temperature from the tenon joint structure to the high-temperature blades. With flow distribution scheme 2, the cooling air distribution is more uniform, leading to a more even overall temperature distribution of the turbine disk. With flow distribution scheme 3, more cooling air flows through the inner cavity of the double-spoke turbine disk, better utilizing its structural cooling advantages, but it is slightly lacking in temperature control at the high-radius area. Therefore, the specific cooling air flow arrangement scheme should be determined based on the specific heat exchange requirements.

Claims

1. A cold airflow path structure suitable for a double-spoke turbine disk, characterized in that, The device includes a double-spoke turbine disk (1) and a tenon (6) for connecting with the turbine blades. The double-spoke turbine disk (1) includes front and rear spokes and a hollow annular cavity (4) formed by the front and rear spokes. An annular slot (3) communicating with the center of the disk is opened at one end of the cavity (4). Several cold air outlet holes (9) communicating with the cavity (4) are opened on the edge of the double-spoke turbine disk (1). An air inlet hole (5) communicating with the cavity (4) is opened on the front spoke (11) of the turbine disk near the edge. A mortise (7) matching the tenon (6) is opened on the edge of the double-spoke turbine disk (1). The cold air... The outlet hole (9) is located on the mortise (7), and the tenon (6) is installed in the mortise (7). A gap (10) is left between the inner end of the tenon (6) and the bottom of the mortise (7). A through hole (8) is opened on the tenon (6). The through hole (8), the cold air outlet hole (9) and the gap (10) are interconnected. The two sides of the gap (10) pass through the two sides of the double-spoke turbine disk (1) to form the first flow path. The through hole (8) and the cold air outlet hole (9) are coaxially arranged to form a cold air outlet channel. The cold air outlet channel and the first flow path are perpendicular to each other. The central axis of the cold air outlet hole (9) and the through hole (8) are both perpendicular to the turbine disk rotation axis. Cooling gas enters the disk cavity (4) through the slot (3) and the air inlet (5), cools the double-spoke turbine disk (1), and flows out through the through hole (8) after passing through the cold gas outlet hole (9) and the gap (10); cooling gas also flows in from the first flow path inlet and flows out from the first flow path outlet; The air inlet (5), the cavity (4), the cold air outlet (9), the gap (10), and the through hole (8) are connected in sequence to form a second flow path; the slot (3), the cavity (4), the cold air outlet (9), the gap (10), and the through hole (8) are connected in sequence to form a third flow path.

2. The cold airflow path structure for a double-spoke turbine disk as described in claim 1, characterized in that, The central axis of the air inlet (5) forms an angle of 10°-30° with the rotating axis of the turbine disk.

3. The cold airflow path structure for a double-spoke turbine disk as described in claim 1, characterized in that, The radial height of the gap is 10%-60% of the total radial height of the tenon connection structure after the tenon (6) is installed in the mortise (7).

4. The cold airflow path structure suitable for a double-spoke turbine disk as described in claim 1, characterized in that, The first flow path accounts for 10.0% of the total cold air volume, the second flow path accounts for 73.3% of the total cold air volume, and the third flow path accounts for 16.7% of the total cold air volume.

5. The cold airflow path structure suitable for a double-spoke turbine disk as described in claim 1, characterized in that, The first flow path accounts for 10.0% of the total cold air volume, the second flow path accounts for 40% of the total cold air volume, and the third flow path accounts for 50% of the total cold air volume.

6. The cold airflow path structure for a double-spoke turbine disk as described in claim 1, characterized in that, The first flow path accounts for 10.0% of the total cold air volume, the second flow path accounts for 16.7% of the total cold air volume, and the third flow path accounts for 73.3% of the total cold air volume.

Images