Asymmetrical wedge-shaped vortex generator applied to flow control over compressor cascade and design method thereof

A vortex generator and cascade flow technology, applied in mechanical equipment, gas turbine devices, machines/engines, etc., can solve the problems of inability to efficiently reduce compressor flow loss, unreasonable structure, and weak compressor flow loss, etc. The effect of low total pressure loss, reduced airflow separation, and reduced form resistance loss

Inactive Publication Date: 2018-11-06

NORTHWESTERN POLYTECHNICAL UNIV

6 Cites 4 Cited by

AI-Extracted Technical Summary

Problems solved by technology

[0003] In order to solve the problem that the existing wedge-shaped vortex generator cannot effectively reduce the flow loss of the compressor due to the unreasonable structure, the present invention proposes an asymmetric wedge-shaped vortex generator and its design method applied to the flow control of the compressor cascade

Therefore, the project team proposed an asymmetric wedge-shaped vortex genera...

Abstract

The invention provides an asymmetrical wedge-shaped vortex generator applied to flow control over a compressor cascade and a design method thereof. The structure of the wedge-shaped vortex generator is redesigned, the dimension of the vortex generator which controls the branch side of a suction surface is decreased as far as possible, so that the form drag loss and the gas flow separation on the suction surface side are effectively reduced, and the problem that the capacity of lowering the flow loss of a compressor of the wedge-shaped vortex generator is not high is solved. The asymmetrical wedge-shaped vortex generator is introduced, so that suction surface vortexes and pressure surface vortexes are induced to be generated, the structure and transverse flowing of channel vortexes are changed through low-energy fluid rolling an adsorption side layer, gas flow separation on the suction surface/an end wall corner area is reduced, and therefore the total pressure loss of the compressor cascade is lowered.

Application Domain

Gas turbine plantsJet propulsion plants

Technology Topic

AirflowEngineering +6

Image

Examples

Experimental program(1)

Example Embodiment

[0026] The embodiments of the present invention are described in detail below. The embodiments are exemplary and are intended to explain the present invention, but should not be understood as a limitation to the present invention.

[0027] In this embodiment, an asymmetric wedge-shaped vortex generator method for flow control of a compressor cascade includes the following steps:

[0028] Step 1: Determine the design parameters of the geometric structure of the wedge-shaped vortex generator as radial height, axial length, suction side width and pressure side width. Reference figure 1 , The asymmetric wedge-shaped vortex generator has a tetrahedral structure as a whole. The geometric dimensions are determined by the radial height 1, the axial length 2, the suction side width 3, and the pressure side width 4. 5 is the vertical point of the triangle bottom on the top surface of the asymmetric wedge-shaped vortex generator. The radial height 1 is perpendicular to the bottom end wall.

[0029] Step 2: Keep the suction side width 3 and pressure side width 4 equal, adjust the radial height 1, axial length 2, and suction side width 3 and pressure side width 4 of the wedge-shaped vortex generator within the design domain of the design parameters Considering to improve the universality of the device, the height of the vortex generator is related to the thickness of the surface layer, and a total of 12 design schemes are obtained; see Table 1:

[0030] Table 1 12 kinds of wedge-shaped vortex generator sizes

[0031]

[0032]

[0033] Step 3: Model the design schemes of several wedge-shaped vortex generators obtained in step 2 respectively, and use computational fluid dynamics to test the improvement effect of the wedge-shaped vortex generator on the performance of the compressor cascade under different design schemes, and get the wedge-shaped vortex generation The optimized value range of the design parameters of the device; among which refer to figure 2 , image 3 In the computational fluid dynamics software, the installation relationship between the wedge-shaped vortex generator model and the compressor cascade model is: the wedge-shaped vortex generator model is installed on the end wall of the leading edge of the compressor cascade blade 6 model, and the top surface of the wedge-shaped vortex generator The distance between the vertical point 5 of the triangle base and the leading edge point 7 of the blade is 0.5 mm, and the line connecting the two points is perpendicular to the base.

[0034] In this embodiment, an unstructured grid is used to model the design of the wedge-shaped vortex generator to reduce the total pressure loss as a basis for evaluating the performance improvement of the compressor cascade. The ability of the wedge-shaped vortex generator to reduce the total pressure loss is measured by the percentage of total pressure loss reduction. The total pressure loss Loss is defined as follows:

[0035]

[0036] Where p t , P represent total pressure and static pressure respectively, subscript m represents 50% leaf height, and in represents inlet position.

[0037] Figure 4 It is shown that the 12 solutions have reduced the total pressure loss coefficient to varying degrees, and when the wedge-shaped vortex generator size falls within the following range: height 10-12.5mm, length 31-36mm, width 16-24mm, the total pressure loss is reduced. The best results.

[0038] Step 4: Within the optimized value range of the design parameters of the wedge-shaped vortex generator obtained in step 3, adjust the ratio of the suction side width 3 and the pressure side width 4, and obtain 26 asymmetric wedge vortex generator designs through the uniform design method Scheme; see Table 2.

[0039] Table 2 Size schemes of 26 asymmetric wedge-shaped vortex generators with uniform design

[0040]

[0041]

[0042] Step 5: Use unstructured grids to separately model several asymmetric wedge-shaped vortex generator design schemes obtained in step 4, and use computational fluid dynamics to test the asymmetric wedge-shaped vortex generators against compressor blades under different design schemes. The improvement of the grid performance results in the optimal asymmetric wedge-shaped vortex generator design.

[0043] Figure 5 It is shown that the total pressure loss coefficient of the 26 kinds of schemes of installing an asymmetric wedge-shaped vortex generator is more than 10.8% lower than that of the prototype cascade. Prove the effectiveness of the control method. Among them, Scheme 21 (radial height 12mm, axial length 35.6mm, suction side width 7.5mm, pressure side width 11.1mm) has the smallest total pressure loss, which is 21.03% less than the prototype cascade loss.

[0044] In order to further compare the effects of symmetric wedge-shaped vortex generators and asymmetric wedge-shaped vortex generators with similar dimensions on the total pressure loss of the flow field, two comparison schemes of symmetric wedge-shaped vortex generators were designed: Scheme 1: height 12mm, length 35.6mm, The width of the suction side is 7.5mm, and the width of the pressure side is 7.5mm; Option 2: Height 12mm, length 35.6mm, suction side width 11.1mm, pressure side width 11.1mm.

[0045] Image 6 with Figure 7 It shows that, compared with the symmetrical wedge-shaped vortex generator, the implementation of the asymmetrical wedge-shaped vortex generator can more effectively improve the distribution of flow loss along the flow direction, reduce the backflow area in the cascade channel, and greatly improve the blockage of the channel. , Thereby reducing the total pressure loss.

[0046] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art will not depart from the principle and purpose of the present invention. Under the circumstances, changes, modifications, substitutions and modifications can be made to the above-mentioned embodiments within the scope of the present invention.

PUM

Property	Measurement	Unit
Radial height	12.0	mm
Axial length	35.6	mm

Description & Claims & Application Information

We can also present the details of the Description, Claims and Application information to help users get a comprehensive understanding of the technical details of the patent, such as background art, summary of invention, brief description of drawings, description of embodiments, and other original content. On the other hand, users can also determine the specific scope of protection of the technology through the list of claims; as well as understand the changes in the life cycle of the technology with the presentation of the patent timeline. Login to view more.

Similar technology patents

Biomass pyrolysis gasification furnace of star composite structure

PendingCN106996564Areduce overall sizeSmall footprint

Owner:广东英翔科技有限公司

Sound wave phase modulation and sound field reconstruction method based on near-field orbital angular momentum conversion

ActiveCN114543980Asmall geometryIncrease Pixel Density

Owner:BEIJING INSTITUTE OF TECHNOLOGYGY