CN-116263837-B - Pneumatic design method for bionic tower-type wind turbine

Abstract

The invention discloses a pneumatic design method for a bionic tower type wind turbine, which comprises the steps of 1) carrying out bionic modeling on the geometric shape of a tower column of the wind turbine by three-dimensional modeling software to determine the size of the tower column, 2) adopting numerical simulation calculation to study the pneumatic characteristics of the bionic tower column and a cylindrical tower column, 3) 3D printing a tower column model and uniformly distributing pressure measuring holes, 4) arranging a wind tunnel test device, 5) adopting wind tunnel test to collect data to study the pneumatic characteristics of the bionic tower column and the cylindrical tower column, 6) adopting the three-dimensional modeling software to model a wind turbine blade, a hub and a cabin, combining the designed bionic tower column with a rotary blade, and 7) adopting numerical simulation calculation to compare the simulation calculation results of the bionic tower type wind turbine and the cylindrical tower type wind turbine. The invention directly starts from the design angle of the appearance of the tower column, has simple and efficient optimization steps, has better vibration reduction and damping and wake flow improvement effects, and thus, improves the output power of the wind turbine.

Inventors

• HUANG XIAOQIAN
• HU XUEQIN
• YANG JUNWEI
• YANG HUA

Assignees

• 扬州大学

Dates

Publication Date

20260505

Application Date

20230315

Claims (3)

1. 1. The pneumatic design method for the bionic tower-type wind turbine is characterized by comprising the following steps of: Step 1) carrying out improved design on a tower column of a wind turbine by using three-dimensional modeling software, improving an existing seal beard model, and simultaneously selecting a traditional smooth cylindrical tower column with the same hydraulic diameter for comparison research; changing the length-axis ratio of two elliptical control sections and the inclination angle of the two elliptical control sections with a horizontal plane, taking the elliptical control section at the central height of the tower as a basic surface, rotating the elliptical control section above the basic surface anticlockwise by an angle gamma around the central line of the height direction of the tower relative to the next adjacent control surface in sequence, and rotating the elliptical control section below the basic surface clockwise by the angle gamma around the central line of the height direction of the tower relative to the last adjacent control surface in sequence to make the tower spiral along the height direction; Step 2) adopting a numerical simulation calculation method, comparing the improved bionic tower column model with a cylindrical tower column model, analyzing from the aspects of tower column surface force, speed distribution, flow mode and pressure distribution, and researching the aerodynamic characteristics of the tower columns with different appearance structures; Step 3) 3D printing an improved bionic tower column model and a cylindrical tower column model, and uniformly distributing pressure measuring holes on the section of the node and the section of the saddle point; step 4) arranging a wind tunnel test device, and carrying out a test by adopting an electronic pressure scanning valve and a hot wire anemometer; step 5) adopting a wind tunnel test method to collect data, comparing the surface pressure aerodynamic force and wake of the cylindrical tower column model and the bionic tower column model, and researching the aerodynamic characteristics of the tower columns with different appearance structures; The method for adopting the wind tunnel test specifically comprises the steps of collecting data under a subcritical Reynolds number region with a calculated working condition of Reynolds number R_e=30000, wherein a hole is preset in the bottom of the wind tunnel test device, so that a pressure hose can be conveniently connected to an electronic pressure collecting system, and a disc is arranged at the top of a test cylinder to eliminate the interference of the end part; Step 6) modeling the wind turbine blade, the hub and the engine room by using three-dimensional modeling software, and combining the designed bionic tower column with the rotating blade to apply the bionic tower column to the horizontal axis wind turbine; step 7) adopting a numerical simulation calculation method, comparing a series of simulation calculation results of aerodynamic performance and wake field characteristics of the bionic tower-type wind turbine and the cylindrical tower-type wind turbine, and researching the influence of tower shadow effect on the load born by the blades, axial stress of the rotating wind wheel and instantaneous torque of the tower with different appearance structures; the numerical simulation calculation method in the step 2) and the step 7) specifically comprises the steps that the calculation working conditions are subcritical Reynolds number areas with Reynolds numbers R e =30000, the applied turbulence model is a four-way transition model formed by coupling a gamma-Re θ transition model and a k-omega SST model, the simulation working conditions are different wind attack angles, the bionic tower column model and the cylindrical tower column model are compared, and calculation analysis is conducted from the aspects of tower column surface force, speed distribution, flow mode and pressure distribution.
2. 2. The aerodynamic design method for a bionic tower-type wind turbine according to claim 1, wherein the surface pressure aerodynamic force measurement of the cylindrical tower model in step 5) is processed by adopting formula (1); In the formula (1), p j is j number of pressure measurement hole static pressures j=1 to 19, p 0 is incoming flow static pressure of a pitot tube test, ρ is incoming flow air density, U 0 is free flow speed, and C p is pressure coefficient of a measuring hole on a section.
3. 3. The aerodynamic design method for a bionic tower type wind turbine according to claim 1, wherein in the step 5), the surface pressure aerodynamic force measurement of the bionic tower type is processed by adopting a formula (2) and a formula (3); In the formulas (2) and (3), C l is the lift coefficient of each section of the bionic cylinder, C d is the resistance coefficient of each section of the bionic cylinder, θ is the included angle between the measuring point position and the original standing point, the value is from 0 to 180 degrees, and N is the measuring point arranged within the range of 0 to 180 degrees.

Description

Pneumatic design method for bionic tower-type wind turbine Technical Field The invention relates to the field of aerodynamic characteristics optimization design of wind turbines, in particular to an aerodynamic design method for a bionic tower-type wind turbine. Background The energy is closely related to human society, and is an important material foundation for developing production and improving human living standard. With population growth and economic development, the demand for energy is also increasing, and in the current generation of shortage of fossil fuels, along with the increasing global climate change, the development of clean renewable energy has become one of the most urgent energy problems in the world today. The wind energy is used as sustainable renewable energy, clean and pollution-free, and has high ecological environment benefit value. The number of globally available wind resources is about 4350GW, with about 1000GW land and 200GW offshore being commercially available using existing technology. The wind power source is sufficient in China, chinese operators are wide, coastline is long and tortuous, and the wind power source is extremely rich. Greatly improves the wind energy utilization ratio of China, and is an important measure for realizing the national energy strategy of 3060. With the rapid development of the global wind turbine industry, the large-scale wind turbine has become a future development trend. The design structure of cylindrical thin-wall tower columns is adopted in most of modern large megawatt horizontal axis variable pitch constant frequency wind turbines, and because wind in nature is changed more and more in space and time in practical engineering application, the influence of wind on the structure, the load and other aspects of blades and tower columns of the wind turbines is correspondingly complicated, when fluid passes through the wind turbines, karman vortex streets which frequently fall off are generated behind the tower columns, vortex streets and columns interact to form vortex-induced vibration, and the phenomenon can cause serious potential safety hazards to the structure of the tower columns; in addition, when fluid passes through the wind turbine, the blocking effect of the tower column can generate a tower shadow effect, the effect can influence aerodynamic load on the blades, the fatigue life and output power of the blades are reduced, and meanwhile, the tower shadow effect can also influence a wake flow area of the wind turbine, so that the power output of a downstream wind turbine is influenced. Bionic researches show that compared with a smooth cylinder, the average resistance and the pulsation resistance of the seal beard surrounding flow field are greatly reduced, beard vibration is obviously weakened, and the vortex shedding process is greatly inhibited, so that the pulsation pressure on the surface of the cylinder is reduced. Therefore, the pneumatic design for the bionic tower type wind turbine is provided, a method combining experimental measurement and numerical calculation is adopted, the influence mechanism of the bionic tower on load shedding and power increasing of the horizontal axis wind turbine blade is systematically researched, the resistance characteristic and wake flow structure of the traditional cylindrical tower are changed, the tower shadow effect of the tower on the blade is reduced, so that the wind turbine can be ensured to reduce potential safety hazards as much as possible, and the power output is improved. Disclosure of Invention The invention aims to overcome the defects of the prior art, provides a pneumatic design method for a bionic tower-type wind turbine, is suitable for pneumatic design of a tower column of the wind turbine under different working conditions, improves the influence caused by the tower shadow effect, improves the power output of the wind turbine, provides theoretical basis and scientific basis for pneumatic optimization design of the horizontal-axis wind turbine, and is beneficial to practical application of the wind turbine. The invention aims to realize the pneumatic design method for the bionic tower-type wind turbine, which comprises the following steps of: step 1) carrying out improved design on a tower column of a wind turbine by using three-dimensional modeling software, improving an existing seal beard model, and simultaneously selecting a traditional smooth cylindrical tower column with the same hydraulic diameter for comparison research; Step 2) adopting a numerical simulation calculation method, comparing the improved bionic tower column model with a cylindrical tower column model, analyzing from the aspects of tower column surface force, speed distribution, flow mode and pressure distribution, and researching the aerodynamic characteristics of the tower columns with different appearance structures; Step 3) 3D printing an improved bionic tower column model and a cylindrical tower colum