CN110531619B - Method for realizing flow control - Google Patents

Method for realizing flow control Download PDF

Info

Publication number
CN110531619B
CN110531619B CN201910804157.2A CN201910804157A CN110531619B CN 110531619 B CN110531619 B CN 110531619B CN 201910804157 A CN201910804157 A CN 201910804157A CN 110531619 B CN110531619 B CN 110531619B
Authority
CN
China
Prior art keywords
channel
wing
turbulence
distance
controllers
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201910804157.2A
Other languages
Chinese (zh)
Other versions
CN110531619A (en
Inventor
刘雪玲
汪健生
焦钰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tianjin University
Original Assignee
Tianjin University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tianjin University filed Critical Tianjin University
Priority to CN201910804157.2A priority Critical patent/CN110531619B/en
Publication of CN110531619A publication Critical patent/CN110531619A/en
Application granted granted Critical
Publication of CN110531619B publication Critical patent/CN110531619B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B13/00—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion
    • G05B13/02—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric
    • G05B13/04—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators
    • G05B13/042—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators in which a parameter or coefficient is automatically adjusted to optimise the performance

Landscapes

  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Artificial Intelligence (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Evolutionary Computation (AREA)
  • Medical Informatics (AREA)
  • Software Systems (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Aerodynamic Tests, Hydrodynamic Tests, Wind Tunnels, And Water Tanks (AREA)

Abstract

The invention relates to a method for realizing flow control, which comprises a plurality of miniature wing-shaped turbulence controllers with self-adaptive deformation characteristics and an arrangement mode on the surface of a channel, wherein the miniature wing-shaped turbulence controllers are made of self-adaptive deformation, namely flexible materials, the bottom surfaces of the miniature wing-shaped turbulence controllers are fixed on the surface of the channel, are vertical to the flow direction of fluid in the channel and are arranged in a plurality of arrays, and the space between the miniature wing-shaped turbulence controllers is the statistical average width of a velocity band in a turbulence program simulating structure.

Description

Method for realizing flow control
Technical Field
The invention relates to a novel flow control technology and an implementation method thereof, wherein a miniature wing-shaped turbulence controller with self-adaptive deformation characteristics is arranged on the surface of a channel according to a certain requirement, and the reduction of flow resistance is realized by controlling a turbulence flow structure, so that the flow control technology can be widely applied to the fields of heat energy engineering, aerospace engineering and the like.
Background
The existing drag reduction technologies are many, and can be specifically divided into:
1. the method of adding other substances to the wall surface, such as surface polymer coating, micro-bubble and other drag reduction methods;
2. boundary layer control method: trying to delay or make the transition of the wall surface boundary layer larger, and adopting an elastic wall surface method, an air suction method and the like;
3. non-smooth surface method: such as a trench method, etc.
On the basis of this, methods of rib drag reduction (groove method), polymer additive method, compliant wall method, microbubble method, biomimetic drag reduction, wall vibration drag reduction, and the like have been developed.
In the existing drag reduction technology, there is a technology for reducing drag reduction by delaying transition of a boundary layer, which reduces flow resistance by fluidizing a turbulent layer, but does not directly control a quasi-sequence structure in the boundary layer in turbulence, thereby realizing the situation of flow drag reduction.
Disclosure of Invention
In order to solve the problems, overcome the defects of the prior art and combine with the bionics principle, the invention designs a novel flow control technology and an implementation method thereof, a miniature wing-shaped turbulence controller with self-adaptive deformation characteristics is arranged on the surface of a channel according to certain requirements, and the reduction of flow resistance can be realized by controlling the flow structure in a turbulence boundary layer. In order to achieve the purpose, the invention adopts the following technical scheme:
a method for realizing flow control comprises a plurality of miniature wing-shaped turbulence controllers with self-adaptive deformation characteristics and an arrangement mode on the surface of a channel, wherein the miniature wing-shaped turbulence controllers are made of self-adaptive deformation flexible materials, the bottom surfaces of the miniature wing-shaped turbulence controllers are fixed on the surface of the channel and are vertical to the flow direction of fluid in the channel, and a plurality of miniature wing-shaped turbulence controllers are arranged in an array mode, the distance between the miniature wing-shaped turbulence controllers is the statistical average width of a velocity band in a turbulence program simulating structure, and the method comprises the following steps:
the method comprises the following steps: measuring the characteristic length L (m) of the channel, the flow direction section A (m) of the channel2) Length L of the channel0(m)Width of channel Z0(m) average flow velocity Um(m/s) according to the formula of mass flow in the channel Q ═ UmA(m3S) estimated or measured density ρ (m) of the fluid3Kg) and the kinematic viscosity of the fluid, i.e., the kinematic viscosity of the fluid, i.
Figure BDA0002183147020000021
Can be calculated to determine
Figure BDA0002183147020000022
Step two: an abstract physical model of the channel is built and gridded ANSYS ICEM: using empirical formulas
Figure BDA0002183147020000023
L (m) is a characteristic length, let y+Determining the height delta y (m) of a first layer of grid on the boundary of the channel model, and obtaining a computational grid required by numerical calculation according to a grid division method on the basis of determining the first layer of grid on the boundary of the channel model;
step three:introducing the calculation grid obtained in the step two into an ANSYS Fluent, calculating by using a large-vortex numerical simulation method, keeping constant mass flow by adopting periodic boundary conditions for the boundary conditions of the inlet and the outlet of the channel, and obtaining the shear stress tau on the surface of the channel model according to the numerical simulation resultw(N/m2) The surface of the channel model is an object needing enhanced heat transfer;
step four: using shear stress tau of channel model surface in numerical simulation resultsw(N/m2) The fluid density ρ (kg/m) is known3) Calculating the frictional velocity of the surface of the channel model
Figure BDA0002183147020000024
Step five: height without dimension
Figure BDA0002183147020000025
From the kinematic viscosity v (m) of the fluid2S) and the friction speed uτ(m/s) is calculated, y (m) is the actual height, ρ (kg/m)3) Is the fluid density; y is+When 1 denotes a unit dimensionless height, use
Figure BDA0002183147020000026
To express a unit dimensionless height of 1, y1(m) to represent a unit dimensionless height
Figure BDA0002183147020000027
A corresponding actual height;
step six: and (3) designing the space between the miniature wing-shaped turbulence controllers: the motion center of the velocity bands is located in a turbulent flow near-wall region, the distance between every two adjacent spanwise velocity bands is 60-180, a lognormal probability distribution is presented, and the average spanwise distance of the bands is 100 wall surface wall units. The dimensionless distance between two adjacent wing shapes is 100, and under the distance, the two adjacent wing shapes can control a turbulence quasi-sequence structure such as a flow direction vortex, so that the flow resistance can be effectively reduced; the front ends of the wing shapes are fixed on the bottom surface along the incoming flow direction; several wing-shaped bodies are arranged along the spanwise direction, and the spanwise dimensionless distance between the adjacent wing-shaped bodies is
Figure BDA0002183147020000028
Let y+When the dimensionless distance is 100, the corresponding actual distance Δ G is y100＝100y1(m) the actual spacing being the pitch of the arrangement of adjacent micro-foil turbulence controllers;
step seven: the front end of a self-adaptive deformation miniature wing-shaped turbulence controller is fixed on the bottom surface of a channel, and the front end of the self-adaptive deformation miniature wing-shaped turbulence controller is arranged in an array form along the incoming flow direction, and the distance is set to be delta G (y)100＝100y1(m) arranged on the actual channel surface; the preferred wing shape is a rectangular parallelepiped sheet with a thickness of 0.2 times the unit dimensionless distance
Figure BDA0002183147020000031
Actual thickness Δ z is 0.2y1(m); length 4 times unit dimensionless distance
Figure BDA0002183147020000032
Actual length Δ x is 4y1(m); unit dimensionless distance of 23 times height
Figure BDA0002183147020000033
Actual height Δ h 23y1(m)。
Due to the adoption of the technical scheme, the invention has the following advantages:
(1) from material analysis, most of the conventional turbulence control devices are made of rigid materials and cannot generate deformation according to fluid movement, and the micro wing-shaped turbulence controller with the self-adaptive deformation characteristic can generate self-adaptive deformation along with the flow of the fluid, so that the resistance of the fluid flowing through can be reduced;
(2) from material analysis, the wing-shaped turbulence controller made of flexible materials can generate self-adaptive bending deformation phenomena aiming at different flow velocities, can adapt to variable working condition, and enables the turbulence controller to be automatically optimized and adapted to the minimum flow resistance;
(3) from the analysis of the arrangement mode, the arrangement mode of a turbulence control device for controlling turbulence has no certain basis, and certain guidance and inspiration are lacked for industrial production and scientific research; the spanwise dimensionless spacing between adjacent airfoils is 100, at which the array type micro airfoil turbulence controllers can control the flow structure and reduce the surface flow resistance;
(4) at present, some technologies for reducing resistance by delaying transition of a boundary layer exist, flow resistance is reduced by fluidizing a turbulent layer, and the flow resistance is reduced by controlling movement of a turbulent structure in a small range according to different principles.
The invention comprises two types of drag reduction types of controlling the drag reduction of a turbulent structure and reducing the flow resistance by the flexible material, thereby realizing the superposition of two drag reduction effects, and the drag reduction effect is better than that of one of the two drag reduction types which are used independently.
According to the novel flow control technology and the implementation method thereof provided by the invention, the array type self-adaptive deformation miniature wing-shaped turbulence controller with the dimensionless spacing of 100 is designed. The self-adaptive deformation can be generated along with the flow of the fluid, the turbulence sequence simulating structure can be better controlled, the surface resistance is further better reduced, and the excellent flow drag reduction effect is realized.
Drawings
FIG. 1 shows the application of adaptive shape-changing micro-airfoil turbulence controllers in a matrix arrangement in a channel flow under the recommended conditions
Figure 2 shows an enlarged view of an adaptively deformable miniature airfoil-shaped turbulence controller arranged in a preferred situation in a channel.
Fig. 3 is a deformation diagram of adaptive deformation micro wing-shaped turbulence controllers arranged in an array, and (a) - (f) are various deformation modes.
Detailed Description
The present invention will be further described with reference to specific embodiments for the purpose of facilitating an understanding of technical means, characteristics of creation, objectives and functions realized by the present invention, but the following embodiments are only preferred embodiments of the present invention, and are not intended to be exhaustive. Based on the embodiments in the implementation, other embodiments obtained by those skilled in the art without any creative efforts belong to the protection scope of the present invention. The experimental methods in the following examples are conventional methods unless otherwise specified, and materials, reagents and the like used in the following examples are commercially available unless otherwise specified.
The invention comprises a miniature wing-shaped turbulence controller body with self-adaptive deformation characteristics and an arrangement mode on the surface of a channel. The miniature wing-shaped turbulence controllers are made of self-adaptive deformation (flexible) materials, and the bottom surfaces of the miniature wing-shaped turbulence controllers are fixed on the surface of the channel, are vertical to the flow direction of fluid in the channel, and are arranged in an array manner. The micro-foil turbulence controller pitch in the present invention is the statistical average width of the velocity bands in the turbulence program structure, i.e., a unit dimensionless length of 100.
The size design and the arrangement mode of the wing-shaped turbulence controller based on the self-adaptive deformation (flexibility) comprise the following steps
The method comprises the following steps: measuring the characteristic length L (m) of the channel, the flow direction section A (m) of the channel2) Length L of the channel0(m) channel width Z0(m) average flow velocity Um(m/s) according to the formula of mass flow in the channel Q ═ UmA(m3S) estimated or measured density ρ (m) of the fluid3Kg) and the kinematic viscosity of the fluid, i.e., the kinematic viscosity of the fluid, i.
Figure BDA0002183147020000041
Can be calculated to determine
Figure BDA0002183147020000042
Step two: an abstract physical model of the channel is built and gridded ANSYS ICEM: using empirical formulas
Figure BDA0002183147020000043
L (m) is a characteristic length, let y+Determining the height delta y (m) of a first layer of grid on the boundary of the channel model, and obtaining a computational grid required by numerical calculation according to a grid division method on the basis of determining the first layer of grid on the boundary of the channel model;
step three: introducing the calculation grid obtained in the step two into an ANSYS Fluent, calculating by using a large-vortex numerical simulation method, keeping constant mass flow by adopting periodic boundary conditions for the boundary conditions of the inlet and the outlet of the channel, and obtaining the shear stress tau on the surface of the channel model according to the numerical simulation resultw(N/m2) The surface of the channel model is an object needing enhanced heat transfer;
step four: using shear stress tau of channel model surface in numerical simulation resultsw(N/m2) The fluid density ρ (kg/m) is known3) Calculating the frictional velocity of the surface of the channel model
Figure BDA0002183147020000051
Step five: height without dimension
Figure BDA0002183147020000052
From the kinematic viscosity v (m) of the fluid2S) and the friction speed uτ(m/s) is calculated, y (m) is the actual height, ρ (kg/m)3) Is the fluid density; y is+When 1 denotes a unit dimensionless height, use
Figure BDA0002183147020000053
To express a unit dimensionless height of 1, y1(m) to represent a unit dimensionless height
Figure BDA0002183147020000054
A corresponding actual height;
step six: the pitch of the miniature wing-shaped turbulence controller in the invention is the statistical average width of the velocity bands in the turbulence program structure, namely 100 times of the unit dimensionless length. The center of motion of the velocity fringes is located in the turbulent near-wall region. The spacing between the spanwise adjacent speed strips is 60-180, a lognormal probability distribution is presented, and the average spanwise spacing of the strips is 100 wall surface wall units. Through research, the dimensionless distance between two adjacent wing-shaped bodies is 100, and at the distance, the two adjacent wing-shaped bodies can control the turbulence quasi-sequence structure such as flow direction vortexTherefore, the flow resistance can be effectively reduced; the front ends of the wing shapes are fixed on the bottom surface along the incoming flow direction; several wing-shaped bodies are arranged along the spanwise direction, the spanwise direction is very thin, and the spanwise dimensionless distance between every two adjacent wing-shaped bodies is
Figure BDA0002183147020000055
Let y+When the dimensionless distance is 100, the corresponding actual distance Δ G is y100＝100y1(m) the actual spacing being the pitch of the arrangement of adjacent micro-foil turbulence controllers;
step seven: the front end of a self-adaptive deformation miniature wing-shaped turbulence controller is fixed on the bottom surface of a channel, and the front end of the self-adaptive deformation miniature wing-shaped turbulence controller is arranged in an array form along the incoming flow direction, and the distance is set to be delta G (y)100＝100y1(m) arranged on the actual channel surface; the preferred wing shape is a rectangular parallelepiped sheet with a thickness of 0.2 times the unit dimensionless distance
Figure BDA0002183147020000056
Actual thickness Δ z is 0.2y1(m); length 4 times unit dimensionless distance
Figure BDA0002183147020000057
Actual length Δ x is 4y1(m); unit dimensionless distance of 23 times height
Figure BDA0002183147020000058
Actual height Δ h 23y1(m)。
The invention is described in detail below with reference to the figures and examples.
The present invention provides the use of adaptive shape changing micro aerofoil turbulence controllers in a matrix arrangement in a channel flow as shown in the preferred embodiments of figures 1-2. The array type self-adaptive deformation micro wing-shaped turbulence controller arranged on the surface of a channel is used for controlling a flow structure and comprises the channel 1 and a channel fluid inlet 2, wherein the front end 3 of the self-adaptive deformation micro wing-shaped turbulence controller is fixed on the surface of the channel, the parts 4 of the self-adaptive deformation micro wing-shaped turbulence controller except the front end are not fixed, the self-adaptive deformation micro wing-shaped turbulence controller is arranged in an array type and at equal intervals, and the channel fluid outlet 5 is arranged. Figure 3 shows a deformed diagram of an array of equally spaced adaptively deformed miniature aerofoil turbulence controllers arranged on the surface of a channel.
Specifically, the method comprises the following steps:
average flow rate U as flow ratemWith reference to 0.547(m/s) of air flowing through the channel, the channel half height (as a characteristic length) is L0.1 (m), and the channel length is L01.256(m), channel width Z00.628(m), air density ρ 1.225 (m)3Kg), aerodynamic viscosity μ 1.7894e-05(kg/(m · s)), the kinematic viscosity of air
Figure BDA0002183147020000061
The method comprises the following steps: characteristic length L of measuring channel is 0.1(m), average flow speed Um0.547(m/s) depending on the kinematic viscosity of the fluid
Figure BDA0002183147020000062
Determining
Figure BDA0002183147020000063
Step two: an abstract physical model of the channel is built at ANSYS ICEM, using
Figure BDA0002183147020000064
(this empirical formula was proposed by Schlichting in 1979), the characteristic length L is 0.1(m), let y+Determining that the height of a first layer grid on the boundary of the channel model is delta y approximately equal to 0.00035(m) so as to establish a calculation grid;
step three: introducing a calculation grid into ANSYS Fluent, and calculating by using a large-vortex numerical simulation method to obtain the shear stress tau of the surface of the channel modelw≈0.00145(N/m2)；
Step four: the shear stress tau of the channel surface (the object needing enhanced heat transfer) in the numerical simulation result is utilizedw≈0.00145(N/m2) The known air density ρ is 1.225 (kg/m)3) Calculating the frictional velocity of the surface of the passage
Figure BDA0002183147020000065
Step five: height without dimension
Figure BDA0002183147020000066
y (m) is the actual height, and the air density ρ is 1.225 (m)3Kg), aerodynamic viscosity μ 1.7894e-05(kg/(m · s)), kinematic viscosity of air
Figure BDA0002183147020000067
Frictional velocity uτ≈0.0344(m/s)；y+When 1 denotes a unit dimensionless height, use
Figure BDA0002183147020000068
To express a unit dimensionless height of 1, y1(m) to represent an actual height corresponding to a unit dimensionless height; let y+1, obtaining unit dimensionless height
Figure BDA0002183147020000069
Corresponding actual height y1≈0.00042(m)；
Step six: the pitch of the miniature wing-shaped turbulence controller in the invention is the statistical average width of the velocity bands in the turbulence program structure, namely 100 times of the unit dimensionless length. The center of motion of the velocity fringes is located in the turbulent near-wall region. The spacing between the spanwise adjacent speed strips is 60-180, a lognormal probability distribution is presented, and the average spanwise spacing of the strips is 100 wall surface wall units. Through research, the dimensionless distance between adjacent wing-shaped bodies is 100, and under the distance, the two adjacent wing-shaped bodies can control a turbulence quasi-sequence structure such as a flow direction vortex, so that the flow resistance can be effectively reduced; the front ends of the wing shapes are fixed on the bottom surface along the incoming flow direction; several wing-shaped bodies are arranged along the spanwise direction, the spanwise direction is very thin, and the spanwise dimensionless distance between every two adjacent wing-shaped bodies is
Figure BDA0002183147020000071
Let y+＝100，Obtaining the corresponding actual distance delta G ═ y when the dimensionless distance is 100100＝100y10.042(m), this actual pitch being the arrangement pitch of adjacent micro-foil turbulence controllers;
step seven: as shown in fig. 2, the front end of the adaptive deformation miniature wing-shaped turbulence controller is fixed on the bottom surface of the channel, and the front end is arranged in an array form along the incoming flow direction, and the distance is set to 100y10.042(m) is arranged on the surface of the actual channel; y is1Approximately equal to 0.00042, the preferred wing shape is a rectangular parallelepiped sheet, very thin in the spanwise direction (z-axis direction), with a thickness of 0.2 times the unit dimensionless distance
Figure BDA0002183147020000072
Actual thickness Δ z is 0.2y10.000084 (m); length 4 times unit dimensionless distance
Figure BDA0002183147020000073
Actual length Δ x is 4y10.00168 (m); unit dimensionless distance of 23 times height
Figure BDA0002183147020000074
Actual height Δ h 23y10.00966 (m). As shown in fig. 1 and 2
Step eight: the micro-airfoil turbulence controller, which is fixed to the surface of the fluid channel, is adaptively deformed, as shown in fig. 3, indicating the good adaptive characteristics of the micro-airfoil turbulence controller.
The invention is inspired by bionics, through observing the movement law of fish and finding, the fish body has very strong flexibility, under the motion state, the skin and wavelike scale of fish can reduce the external resistance in the swimming process effectively, its flexible viscous bottom layer thickens, reduce the speed gradient of the boundary layer of epidermis effectively. Meanwhile, dynamic change can be generated according to the change of external load (stress), so that the velocity gradient and the shearing force on the surface boundary layer are reduced, the power consumption caused by the shearing force is finally reduced, and the effect of reducing the frictional resistance is achieved. Therefore, the flexible wall can reduce energy consumption more than the traditional rigid wall, and the flexible wall material can play a role in effectively saving energy when being applied to the turbulence drag reduction process.
By utilizing the phenomena and the statistical characteristics in the turbulent boundary layer, the invention controls the turbulent structure, thereby realizing the flow drag reduction. The flow structure of a turbulent boundary layer includes several features: generating and evolving a speed band in the boundary layer; the low-speed fluid in the near-wall surface area is affected and bursts; the generation and development of span-wise vortices, flow-wise vortices, etc. Wherein the streamwise vortex structure induces eruption of low velocity fluid in the near wall region (Ejection), Sweep down of the high velocity fluid strip (Sweep), and creates additional reynolds stresses. The center of motion of the velocity fringes is located in the turbulent near-wall region. The spacing between the spanwise adjacent speed strips is 60-180, a lognormal probability distribution is presented, and the average spanwise spacing of the strips is 100 wall surface wall units. Through research, the dimensionless distance between two adjacent wing-shaped bodies is 100, and at the distance, the two adjacent wing-shaped bodies can control a turbulence quasi-sequence structure such as a flow direction vortex, so that the flow resistance can be effectively reduced.

Claims (1)

1. A method for realizing flow control comprises a plurality of miniature wing-shaped turbulence controllers with self-adaptive deformation characteristics and an arrangement mode on the surface of a channel, wherein the miniature wing-shaped turbulence controllers are made of self-adaptive deformation flexible materials, the bottom surfaces of the miniature wing-shaped turbulence controllers are fixed on the surface of the channel and are vertical to the flow direction of fluid in the channel, and a plurality of miniature wing-shaped turbulence controllers are arranged in an array mode, the distance between the miniature wing-shaped turbulence controllers is the statistical average width of a velocity band in a turbulence program simulating structure, and the method comprises the following steps:
the method comprises the following steps: measuring the characteristic length L (m) of the channel, the flow direction section A (m) of the channel2) Length L of the channel0(m) channel width Z0(m) average flow velocity Um(m/s) according to the formula of mass flow in the channel Q ═ UmA(m3S) estimated or measured density ρ (m) of the fluid3Kg) and the kinematic viscosity of the fluid, i.e., the kinematic viscosity of the fluid, i.
Figure FDA0003375818980000011
Can be calculated to determine
Figure FDA0003375818980000012
Step two: an abstract physical model of the channel is built and gridded ANSYS ICEM: using empirical formulas
Figure FDA0003375818980000013
L (m) is a characteristic length, let y+Determining the height delta y (m) of a first layer of grid on the boundary of the channel model, and obtaining a computational grid required by numerical calculation according to a grid division method on the basis of determining the first layer of grid on the boundary of the channel model;
step three: introducing the calculation grid obtained in the step two into an ANSYS Fluent, calculating by using a large-vortex numerical simulation method, keeping constant mass flow by adopting periodic boundary conditions for the boundary conditions of the inlet and the outlet of the channel, and obtaining the shear stress tau on the surface of the channel model according to the numerical simulation resultw(N/m2) The surface of the channel model is an object needing enhanced heat transfer;
step four: using shear stress tau of channel model surface in numerical simulation resultsw(N/m2) The fluid density ρ (kg/m) is known3) Calculating the frictional velocity of the surface of the channel model
Figure FDA0003375818980000014
Step five: height without dimension
Figure FDA0003375818980000015
From the kinematic viscosity v (m) of the fluid2S) and the friction speed uτ(m/s) is calculated, y (m) is the actual height, ρ (kg/m)3) Is the fluid density; y is+When 1 denotes a unit dimensionless height, use
Figure FDA0003375818980000016
To express a sheetBit dimensionless height 1, y1(m) to represent a unit dimensionless height
Figure FDA0003375818980000017
A corresponding actual height;
step six: and (3) designing the space between the miniature wing-shaped turbulence controllers: the motion center of the velocity bands is located in a turbulent flow near-wall area, the distance between every two adjacent velocity bands in the spanwise direction is 60-180, a lognormal probability distribution is presented, and the average spanwise distance of the bands is 100 wall surface wall units; the dimensionless distance between two adjacent wing shapes is 100, and under the distance, the two adjacent wing shapes can control a turbulence quasi-sequence structure such as a flow direction vortex, so that the flow resistance can be effectively reduced; the front ends of the wing shapes are fixed on the bottom surface along the incoming flow direction; several wing-shaped bodies are arranged along the spanwise direction, and the spanwise dimensionless distance between the adjacent wing-shaped bodies is
Figure FDA0003375818980000021
Let y+When the dimensionless distance is 100, the corresponding actual distance Δ G is y100＝100y1(m) the actual spacing being the pitch of the arrangement of adjacent micro-foil turbulence controllers;
step seven: the front end of a self-adaptive deformation miniature wing-shaped turbulence controller is fixed on the bottom surface of a channel, and the front end of the self-adaptive deformation miniature wing-shaped turbulence controller is arranged in an array form along the incoming flow direction, and the distance is set to be delta G (y)100＝100y1(m) arranged on the actual channel surface; the preferred wing shape is a rectangular parallelepiped sheet with a thickness of 0.2 times the unit dimensionless distance
Figure FDA0003375818980000022
Actual thickness Δ z is 0.2y1(m); length 4 times unit dimensionless distance
Figure FDA0003375818980000023
Actual length Δ x is 4y1(m); unit dimensionless distance of 23 times height
Figure FDA0003375818980000024
Actual height Δ h 23y1(m)。
CN201910804157.2A 2019-08-28 2019-08-28 Method for realizing flow control Active CN110531619B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910804157.2A CN110531619B (en) 2019-08-28 2019-08-28 Method for realizing flow control

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910804157.2A CN110531619B (en) 2019-08-28 2019-08-28 Method for realizing flow control

Publications (2)

Publication Number Publication Date
CN110531619A CN110531619A (en) 2019-12-03
CN110531619B true CN110531619B (en) 2022-04-08

Family

ID=68665011

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910804157.2A Active CN110531619B (en) 2019-08-28 2019-08-28 Method for realizing flow control

Country Status (1)

Country Link
CN (1) CN110531619B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114719115B (en) * 2022-03-16 2024-03-19 中国航发沈阳发动机研究所 Structure for adjusting temperature of fluid in pipeline

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101348170A (en) * 2008-09-01 2009-01-21 北京航空航天大学 Wing structure having lamellar flow flowing control and separation control
WO2014123615A2 (en) * 2012-12-05 2014-08-14 Rensselaer Polytechnic Institute Piezoelectric driven oscillating surface
WO2016018953A2 (en) * 2014-07-28 2016-02-04 The Regents Of The University Of Colorado, A Body Corporate Phononic materials used to control flow behavior
CN106703069A (en) * 2017-03-16 2017-05-24 天津大学前沿技术研究院有限公司 Cylindrical foundation sinking device for ground breaking drag resistance and pressure maintenance and sinking method thereof
CN107352042A (en) * 2017-07-10 2017-11-17 中国空气动力研究与发展中心高速空气动力研究所 A kind of drag reduction method in supersonic turbulent boundary layer
CN109185223A (en) * 2018-09-27 2019-01-11 江苏大学 A kind of bionic design method for making centrifugal pump that there is reducing noise and drag performance
CN109915443A (en) * 2019-01-23 2019-06-21 南京理工大学 A kind of automatic control device opened up for profile flow to oscillating electromagnetic power drag reduction

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104395601A (en) * 2012-04-10 2015-03-04 奥金公司 Shrouded fluid turbine with boundary layer energising elements

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101348170A (en) * 2008-09-01 2009-01-21 北京航空航天大学 Wing structure having lamellar flow flowing control and separation control
WO2014123615A2 (en) * 2012-12-05 2014-08-14 Rensselaer Polytechnic Institute Piezoelectric driven oscillating surface
WO2016018953A2 (en) * 2014-07-28 2016-02-04 The Regents Of The University Of Colorado, A Body Corporate Phononic materials used to control flow behavior
CN106703069A (en) * 2017-03-16 2017-05-24 天津大学前沿技术研究院有限公司 Cylindrical foundation sinking device for ground breaking drag resistance and pressure maintenance and sinking method thereof
CN107352042A (en) * 2017-07-10 2017-11-17 中国空气动力研究与发展中心高速空气动力研究所 A kind of drag reduction method in supersonic turbulent boundary layer
CN109185223A (en) * 2018-09-27 2019-01-11 江苏大学 A kind of bionic design method for making centrifugal pump that there is reducing noise and drag performance
CN109915443A (en) * 2019-01-23 2019-06-21 南京理工大学 A kind of automatic control device opened up for profile flow to oscillating electromagnetic power drag reduction

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Heat transfer and flow characteristics in a rectangular channel with small scale vortex generators;Wang jiansheng et al.;《International Journal of Heat and Mass Transfer》;20190416;第208–225页 *
槽道流动与传热的主动控制模式;汪健生等;《机械工程学报》;20111231;第47卷(第24期);第104-110页 *

Also Published As

Publication number Publication date
CN110531619A (en) 2019-12-03

Similar Documents

Publication Publication Date Title
Ashraf et al. Reynolds number, thickness and camber effects on flapping airfoil propulsion
Rojratsirikul et al. Unsteady fluid-structure interactions of membrane airfoils at low Reynolds numbers
Eldredge et al. A computational study of a canonical pitch-up, pitch-down wing maneuver
Rival et al. Recovery of energy from leading-and trailing-edge vortices in tandem-airfoil configurations
CN111460699B (en) Design method of micro-texture with drag reduction function on flat wall surface
Ai et al. Experimental investigation of aerodynamic performance of airfoils fitted with morphing trailing edges
Karbasian et al. Enhancement of propulsive performance of flapping foil by fish-like motion pattern
Guillaud et al. Large Eddy Simulations on a pitching airfoil: Analysis of the reduced frequency influence
Kurt et al. Swimming freely near the ground leads to flow-mediated equilibrium altitudes
Merryisha et al. Experimental and CFD analysis of surface modifiers on aircraft wing: A review
CN110531619B (en) Method for realizing flow control
CN110489823B (en) Size design and arrangement mode of self-adaptive deformation miniature square column vortex generator
Ladopoulos Nonlinear unsteady flow problems by multidimensional singular integral representation analysis
Yan et al. Lift-drag characteristics and unsteady cavitating flow of bionic hydrofoil
Shetty et al. CFD Simulation of Flow Past MAV Wings.
Genç et al. Unsteady flow over flexible wings at different low Reynolds numbers
Tejero et al. Shock wave induced flow separation control by air-jet and rod vortex generators
Dwivedi et al. Aerodynamic performance of micro aerial wing structures at low Reynolds number
Khan et al. Computational analysis of bio-inspired corrugated airfoil with varying corrugation angle
Khan et al. Aerodynamic and experimental analysis of biomimic corrugated dragonfly aerofoil
Isaev et al. Modeling an increase in the lift and aerodynamic efficiency of a thick Göttingen airfoil with optimum arrangement
Saad et al. Numerical analysis for comparison of aerodynamic characteristics of six airfoils
Chandan et al. Efficient study of Aerodynamic Characteristics over NACA 0012 at 1000 Reynolds number using subparametric transformations in Micro Air Vehicle application
Chuang et al. Effects of Reynolds number and inclined angle of stroke plane on aerodynamic characteristics of flapping corrugated airfoil
Kitsios et al. Numerical simulation of lift enhancement on a NACA 0015 airfoil using ZNMF jets

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant