Variable-period coupling rib height bionic S-shaped turbulent flow structure for enhancing on-way heat exchange uniformity
By adopting a bionic S-shaped spoiler structure with variable-period coupling ribs in the gas turbine blade cooling design, the fluctuation period and rib height change rules of the bionic S-shaped spoiler ribs are optimized, which solves the problem of degradation of heat exchange uniformity along the route in traditional cooling designs, and achieves a more efficient cooling effect.
Patent Information
- Application Number
- CN202510367483.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-26
- Publication Date
- 2025-05-13
AI Technical Summary
The traditional gas turbine blade cooling design is difficult to cope with rising temperatures, resulting in a decrease in heat exchange uniformity along the route, especially at the end of the channel.
The bionic S-shaped spoiler structure is adopted for variable-period coupling ribs. By optimizing the fluctuation period and rib height change pattern of the bionic S-shaped spoiler rib fins, the period is gradually reduced and the rib height is increased to improve the uniformity of heat exchange along the route.
The uniformity of heat exchange along the cooling channel is significantly improved, and the heat exchange performance at the end of the channel is avoided due to the rise of the cooling air temperature, which improves the overall performance of the channel.
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Figure CN119982105A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of gas turbine blade cooling, in particular to a variable-period coupled rib height bionic S-shaped spoiler structure for enhancing heat exchange uniformity along the blade. Background Art
[0002] In order to improve the thrust-to-weight ratio of aircraft gas turbines, the current method is mainly to increase the turbine inlet temperature, which puts higher requirements on the cooling design of turbine blades. The traditional internal ribbed channel combined with impingement jet and film cooling technology is no longer sufficient to cope with the increasing temperature, so a more efficient cooling solution is needed.
[0003] The bionic S-shaped spoiler structure can improve the flow and heat transfer performance in the inner cooling channel, but the cooling temperature rise along the flow direction in the channel will lead to a decrease in heat transfer performance. To this end, the present invention proposes a bionic S-shaped spoiler structure with variable period coupling rib height that can enhance the uniformity of heat transfer along the channel. Summary of the invention
[0004] In order to solve the problems existing in the background technology, the present invention is implemented through the following technical solutions: a variable period coupled rib height bionic S-shaped spoiler structure for enhancing the uniformity of heat transfer along the process, including a rib structure, wherein the rib structure is a bionic S-shaped spoiler rib, and the period size and rib height of the bionic S-shaped spoiler rib gradually change along the flow direction.
[0005] Furthermore, the bionic S-shaped spoiler rib is wavy, and the fluctuation of the bionic S-shaped spoiler rib is 10 cycles, and the amplitude and rib thickness in a single cycle remain the same.
[0006] Furthermore, the profile of the bionic S-shaped spoiler fin in a single period is a sine curve.
[0007] Furthermore, the bionic S-shaped spoiler rib has a rib thickness of 2.718 mm and a fluctuation amplitude of 27% of the channel width.
[0008] Furthermore, the period of the bionic S-shaped spoiler fins gradually decreases along the flow direction to weaken the adverse effect of the temperature rise along the flow on the heat exchange at the rear end of the channel.
[0009] Furthermore, the generation formula of the periodic variation of the bionic S-shaped spoiler fin is:
[0010]
[0011] Among them, the contour of the bionic S-shaped spoiler rib is discretized into 6000 points, the value of the discrete point i corresponds to 1 to 6000, y is the amplitude of the bionic S-shaped spoiler rib, n0 is the actual period number of the bionic S-shaped spoiler rib, and n1 is used to control the degree of period change, with a value range of 1-n0.
[0012] Furthermore, the rib height of the bionic S-shaped spoiler rib increases gradually along the flow direction, with an initial height of 2e and a terminal rib height value range of 2e-3.2e.
[0013] Compared with the prior art, the present invention has the following beneficial effects:
[0014] 1. The variable period coupled rib height bionic S-shaped spoiler structure that enhances the uniformity of heat transfer along the cooling channel significantly improves the uniformity of heat transfer along the cooling channel by optimizing the fluctuation period and the variation law of the rib height, and effectively avoids the problem of significantly reduced heat transfer performance at the end of the channel due to the temperature rise of the cold air along the channel. This design can significantly improve the heat transfer uniformity of the channel while ensuring that the channel performance remains basically unchanged, and can also preliminarily give the influence law of the performance of the variable period coupled rib height bionic S-shaped spoiler structure under different period variation amplitudes.
[0015] 2. Compared with the traditional S-shaped spoiler structure, the present application can control the degree of disturbance of the cold air in the channel by adjusting the fluctuation period of the bionic S-shaped spoiler ribs and the variation range of the rib height. In order to eliminate the adverse effects of temperature rise along the way, the period can be gradually reduced along the flow direction and the rib height can be gradually increased, thereby effectively improving the heat exchange efficiency at the trailing edge of the channel. The design of the spoiler structure also takes into account the specific needs of different regions to ensure that the overall performance of the channel is enhanced while ensuring the uniformity of heat exchange along the way. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 Schematic diagram of the performance distribution of the bionic S-shaped spoiler fins under different termination rib heights he of the present invention;
[0017] Figure 2 Schematic diagram of Nu / Nu0 distribution along the wall of the bionic S-shaped spoiler fins of the traditional bionic S-shaped channel and the variable period rib height channel of the present application;
[0018] Figure 3 It is a schematic diagram of a traditional S-shaped ribbed channel;
[0019] Figure 4 This is a schematic diagram of the bionic S-shaped spoiler rib when the termination rib height he is 3.2 and n1 is 7;
[0020] Figure 5 This is the Nu / Nu0 cloud diagram of the ribbed wall of the traditional S-shaped ribbed channel;
[0021] Figure 6 The Nu / Nu0 cloud diagram of the bionic S-shaped spoiler fin wall when the termination rib height he is 3.2 and n1 is 7;
[0022] Figure 7 It is a schematic diagram of the structure of the bionic S-shaped spoiler fin of the present invention. DETAILED DESCRIPTION
[0023] 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 only 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.
[0024] The embodiment of the variable period coupling rib height bionic S-shaped spoiler structure for enhancing the uniformity of heat transfer along the process is as follows:
[0025] See also Figure 1-Figure 7 A variable period coupled rib height bionic S-shaped spoiler structure for enhancing uniformity of heat transfer along the process includes a rib structure, the rib structure is a bionic S-shaped spoiler rib, and the period size and rib height of the bionic S-shaped spoiler rib gradually change along the flow direction.
[0026] It should be noted that the bionic S-shaped spoiler rib is wavy, and the fluctuation of the bionic S-shaped spoiler rib is 10 cycles, and the amplitude and rib thickness related parameters within a single cycle remain the same; the profile of the bionic S-shaped spoiler rib within a single cycle is a sine curve; the rib thickness of the bionic S-shaped spoiler rib is e, in mm, and the value can be 2.718 mm, and the fluctuation amplitude is 27% of the channel width; the rib height of the bionic S-shaped spoiler rib gradually increases along the flow direction, the initial height is 2e, and the terminal rib height ranges from 2e to 3.2e.
[0027] It should also be noted that the period of the bionic S-shaped spoiler fins gradually decreases along the flow direction to weaken the adverse effect of the temperature rise along the flow on the heat exchange at the tail end of the channel.
[0028] Among them, the generation formula of the periodic change of the bionic S-shaped spoiler fin is:
[0029]
[0030] Among them, the contour of the bionic S-shaped spoiler rib is discretized into 6000 points, the value of the discrete point i corresponds to 1 to 6000, y is the amplitude of the bionic S-shaped spoiler rib, n0 is the actual period number of the bionic S-shaped spoiler rib, and n1 is used to control the degree of period change, with a value range of 1-n0.
[0031] like Figure 1 The performance distribution of the bionic S-shaped spoiler fins under different terminal rib heights he is shown in the figure. With the increase of the terminal rib height, the overall heat transfer performance and pressure loss of the bionic S-shaped spoiler fins show a monotonically increasing trend, and the corresponding comprehensive thermal performance TP remains basically unchanged. Compared with the channel of the traditional S-shaped rib (such as Figure 3 and Figure 4As shown), the heat transfer strength of the (new) variable period rib height bionic S-shaped spoiler ribs of the present application has obvious advantages, and the dimensionless Nusselt number (Nu / Nu0) is increased by about 13%.
[0032] like Figure 2 The Nu / Nu0 distribution along the wall of the bionic S-shaped spoiler ribs of the traditional bionic S-shaped channel and the variable period rib height channel of the present application is shown. By comparison, it is found that the heat transfer performance of the bionic S-shaped spoiler ribs of the present application is significantly better than that of the traditional ribs except for the first cycle. Among them, the difference in the tenth cycle is the largest, about 20%. At the same time, it is observed that the difference between the maximum and minimum values of the bionic S-shaped spoiler ribs of the present application along the ten cycles is smaller, only 40% of that of the traditional ribs. After the 4th cycle, the heat transfer performance of the bionic S-shaped spoiler ribs along the flow direction increases slightly, avoiding the decrease in heat transfer capacity along the process due to the rise in the cooling temperature.
[0033] like Figure 5 and Figure 6 As shown, by comparing the Nu / Nu0 cloud diagrams of the walls of the two channels, it can be found that compared with the traditional S-shaped wall channel, the high bionic S-shaped wall channel with variable period bionic S-shaped spoiler ribs of the present application significantly enhances the range and strength of the high heat exchange zone of each heat exchange wall.
[0034] The dimensionless Nusselt number is defined as follows:
[0035] Nu / Nu0=(hD / λ) / 0.023Re 0.8 Pr 0.4 (1)
[0036] In the formula, h is the heat transfer coefficient, D is the characteristic length, λ is the thermal conductivity, Re is the inlet Reynolds number, and Pr is the Prandtl number. The comprehensive heat transfer performance index is defined as follows:
[0037] TP=(Nu / Nu0) / (f / f0) 1 / 3 (2)
[0038] Where f0 = 0.507Re -0.3 f=Δp / (0.5ρU 2 ), Δp is the pressure difference between the inlet and outlet of the channel, ρ is the cold air density, and U is the cold air velocity.
[0039] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A variable period coupled rib height bionic S-shaped spoiler structure for enhancing the uniformity of heat transfer along the process, including a rib structure, characterized in that: The rib structure is a bionic S-shaped spoiler rib, and the periodic size and rib height of the bionic S-shaped spoiler rib gradually change along the flow direction.
2. The variable period coupling rib height bionic S-shaped spoiler structure for enhancing heat transfer uniformity along the process according to claim 1, characterized in that: The bionic S-shaped spoiler rib is wavy, and the fluctuation of the bionic S-shaped spoiler rib is 10 cycles, and the amplitude and rib thickness in a single cycle remain the same.
3. The variable period coupling rib height bionic S-shaped spoiler structure for enhancing heat transfer uniformity along the process according to claim 2, characterized in that: The profile of the bionic S-shaped spoiler fin in a single period is a sine curve.
4. The variable period coupled rib height bionic S-shaped spoiler structure for enhancing heat transfer uniformity along the process according to claim 1, characterized in that: The bionic S-shaped spoiler rib has a rib thickness of 2.718 mm and a fluctuation amplitude of 27% of the channel width.
5. The variable period coupling rib height bionic S-shaped spoiler structure for enhancing heat transfer uniformity along the process according to claim 1, characterized in that: The period of the bionic S-shaped spoiler fins gradually decreases along the flow direction, so as to weaken the adverse effect of the temperature rise along the flow on the heat exchange at the rear end of the channel.
6. The variable period coupling rib height bionic S-shaped spoiler structure for enhancing heat transfer uniformity along the process according to claim 5, characterized in that: The generation formula of the periodic variation of the bionic S-shaped spoiler fin is: Among them, the contour of the bionic S-shaped spoiler rib is discretized into 6000 points, the value of the discrete point i corresponds to 1 to 6000, y is the amplitude of the bionic S-shaped spoiler rib, n0 is the actual period number of the bionic S-shaped spoiler rib, and n1 is used to control the degree of period change, with a value range of 1-n0.
7. The variable period coupling rib height bionic S-shaped spoiler structure for enhancing heat transfer uniformity along the process according to claim 4, characterized in that: The rib height of the bionic S-shaped spoiler rib increases gradually along the flow direction, with an initial height of 2e and a terminal rib height value range of 2e-3.2e.