Bernoulli visual demonstration device

Abstract

The invention relates to the technical field of scientific demonstration, in particular to a Bernoulli visual demonstration device. The airfoil comprises an airfoil horizontally arranged in a normal state and a fan arranged beside one end of the airfoil, a vertically distributed airflow channel is arranged in the airfoil, the airflow channel can be perspective from the outside of the airfoil, the airflow channel communicates with the top surface and the bottom surface of the airfoil, and a light small ball is arranged in an inner cavity of the airflow channel. The small light ball can ascend under the action of pressure difference between the top face and the bottom face of the wing. According to the Bernoulli principle demonstration device, generation of wing lift force can be visually displayed without overall rising movement of the wings in the demonstration process, and the requirement of a large Bernoulli principle demonstration device for the air blowing range of a draught fan is effectively lowered.

Description

Technical Field

[0001] The invention relates to the technical field of scientific demonstration, in particular to a Bernoulli visualization demonstration device. Background Art

[0002] Bernoulli's principle is a basic principle in fluid mechanics, and its essence is the conservation of mechanical energy of an ideal fluid. Its most famous corollary is that when the flow is at equal height, the greater the flow velocity, the smaller the pressure.

[0003] Bernoulli principle demonstration devices are often used for teaching or popular science in science and technology exhibition halls. For example, as recorded in the text of a Bernoulli principle demonstration device with a Chinese patent publication number of CN215007135U, a sliding and rotating wing is set on a base. When in use, when high-speed airflow passes through the upper and lower surfaces of the wing, the wing rotates to a certain angle, which will cause a difference in the flow rate between the upper and lower surfaces of the wing, thereby pushing the wing to slide on the base, and more intuitively demonstrating the process of lift generation. During the demonstration process, this scheme shows the generation of lift through the movement of the wing, which requires the high-speed airflow to completely cover the movement stroke of the wing during the overall ascent. This structural setting is more suitable for small teaching demonstration devices, but when used in large demonstration devices, the requirements for the blowing range of the fan are too large, and a large Bernoulli principle demonstration device cannot be formed, so it is urgent to solve. Summary of the invention

[0004] In order to avoid and overcome the technical problems existing in the prior art, the present invention provides a Bernoulli visualization demonstration device, which can intuitively show the generation of wing lift without the need for the overall upward movement of the wing during the demonstration, effectively reducing the demand for the fan blowing range in large-scale Bernoulli principle demonstration devices.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A Bernoulli visualization demonstration device comprises a wing arranged horizontally in a normal state and a fan arranged beside one end of the wing, a vertically distributed airflow channel is arranged inside the wing, the airflow channel can be seen through from the outside of the wing, and the airflow channel is connected to both the top surface and the bottom surface of the wing, a light ball is arranged in the inner cavity of the airflow channel, and the light ball can move upward under the pressure difference between the top surface and the bottom surface of the wing.

[0007] As a further solution of the present invention: the wing includes an upper top plate and a lower bottom plate, the upper top plate is an elastic steel plate, and a hollow chamber is provided between the upper top plate and the lower bottom plate, a transparent tube fixed to the lower bottom plate and distributed vertically is provided in the hollow chamber, a transparent sleeve is slidably sleeved on the transparent tube, the transparent sleeve and the inner cavity of the transparent tube jointly form an airflow channel, the transparent sleeve is driven to rise and fall by an electric cylinder, and can push the upper top plate to produce elastic deformation.

[0008] As a further solution of the present invention: a push head is fixed on the top of the transparent sleeve, the push head is fixed to the upper top plate, and the top surface of the push head is in an arc structure to fit with the bottom surface of the upper top plate after being elastically deformed by being squeezed therein, and the middle part of the push head has a through hole connected to the inner cavity of the transparent sleeve and the top surface of the upper top plate.

[0009] As a further solution of the present invention: the outer peripheries of the upper top plate and the lower bottom plate are wrapped with silicone cloth.

[0010] As a further solution of the present invention: the wing also includes transparent side panels arranged on both sides of the upper top plate and the lower bottom plate, the transparent side panels are fixed to the lower bottom plate, and the inner walls of the transparent side panels are in contact with the upper top plate.

[0011] As a further solution of the present invention: it also includes a cabinet, the front wall of the cabinet is provided with a mounting groove, the groove of the mounting groove is provided with tempered glass, the fan and the wing are both installed in the mounting groove, and an atomizer is also provided between the fan and the wing.

[0012] As a further solution of the present invention: a rectifier connected to the outside of the cabinet is arranged inside the installation groove, and the rectifier is arranged on the side of the wing away from one end of the fan.

[0013] As a further solution of the present invention: the wing is rotatably connected to the cabinet via a horizontal rotation axis, the horizontal rotation axis is perpendicular to the length direction of the wing, and the rotation angle of the wing is adjustable.

[0014] As a further solution of the present invention: the wings are located on both sides of the horizontal rotating shaft with equal weight so that the wings remain horizontal under normal conditions, a handle penetrating the tempered glass is fixed on the wing, and the tempered glass is provided with an arc-shaped long hole for the handle to slide.

[0015] As a further solution of the present invention: a display screen is provided at the bottom of the installation groove.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. An airflow channel is set inside the wing. When the fan blows air toward the wing and forms a pressure difference between the top and bottom surfaces of the wing, an upward force is generated on the lightweight ball, causing the lightweight ball to move upward in the airflow channel. The lightweight ball rises in the airflow channel to intuitively demonstrate the generation of wing lift, without the need for the overall upward sliding of the wing, effectively reducing the demand for the fan's blowing range in the large-scale Bernoulli principle demonstration device.

[0018] 2. The upper top plate is made of a deformable elastic material, and the airflow channel is composed of the inner cavity of the transparent tube and the inner cavity of the transparent sleeve sliding on the transparent tube, so that the airflow channel forms a floating structure with adjustable length. When the transparent sleeve is driven by the electric cylinder and performs a lifting motion to push the elastic deformation of the upper top plate, the curvature of the upper top plate is changed, thereby changing the pressure difference between the upper and lower surfaces of the wing, realizing the adjustment of the lifting force of the lightweight ball in the airflow channel, thereby enhancing the diversity of the display of Bernoulli's principle.

[0019] 3. Use a push head to push the upper top plate to deform, and use the arc surface structure of the top surface of the push head to fit with the bottom surface of the upper top plate after elastic deformation, to ensure that the top of the upper top plate can form a smooth arc surface structure after extrusion deformation.

[0020] 4. The silicone cloth wrapped around the outer periphery of the upper top plate and the lower bottom plate can keep the overall wing intact after the upper top plate is deformed, further ensuring the integrity of the gas streamlines formed by the airflow on the surface of the upper top plate and the lower bottom plate.

[0021] 5. An atomizer is installed between the fan and the wing to visually display the streamline of the airflow outside the wing.

[0022] 6. The rotation angle of the wing is adjustable. The operator can also further demonstrate the Bernoulli principle by rotating the wing and observing the airflow direction on the upper and lower sides of the wing and the movement state of the small ball inside the wing. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the internal structure of the wing in the present invention.

[0024] Figure 2 It is a structural schematic diagram of the present invention.

[0025] Figure 3 It is a schematic diagram of the internal top view structure of the cabinet in the present invention.

[0026] Figure 4 It is a schematic diagram of the internal top view structure of the wing in the present invention.

[0027] In the figure: 10, cabinet; 11, tempered glass; 111, arc-shaped long hole; 12, mounting slot; 20, display screen; 30, wing; 31, lower base plate; 32, upper top plate; 33, transparent tube; 34, lightweight ball; 35, transparent sleeve; 351, push head; 36, electric cylinder; 37, transparent side panel; 371, handle; 38, silicone cloth; 39, air flow channel; 40, fan; 50, rectifier; 60, atomizer. DETAILED DESCRIPTION

[0028] 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.

[0029] For ease of understanding, the specific structure and working mode of the present invention are further described below in conjunction with the accompanying drawings:

[0030] The specific structure of the present invention refers to Figure 1-4 As shown, its main structure includes a wing 30 arranged horizontally under normal conditions and a fan 40 arranged beside one end of the wing 30. The fan 40 blows air at one end of the wing 30 to form a pressure difference between the top and bottom surfaces of the wing 30. Different from the prior art, the wing 30 of the present application is provided with a vertical distribution airflow channel 39 inside, and the airflow channel 39 can be seen through from the outside of the wing 30, so that the audience can observe the internal state of the airflow channel 39; the airflow channel 39 is connected to both the top and bottom surfaces of the wing 30, and the inner cavity of the airflow channel 39 is provided with a light ball 34. After a pressure difference is formed between the top and bottom surfaces of the wing 30, the light ball 34 can move upward under the pressure difference between the top and bottom surfaces of the wing 30. The present application can intuitively demonstrate the generation of lift force of the wing 30 by the rise of the lightweight ball 34 in the airflow channel 39, without the need for the wing 30 to rise and slide as a whole, effectively reducing the demand for the blowing range of the fan 40 in the large-scale Bernoulli principle demonstration device. Of course, in actual implementation, the traditional demonstration mechanism of the overall rise and slide of the wing 30 can also be used in conjunction with the airflow channel 39 and the lightweight ball 34 in the present application to achieve the dual demonstration effects of the rise of the wing 30 and the rise of the lightweight ball 34.

[0031] On the basis of the above, in order to demonstrate the influence of different curvatures of the top surface of the wing 30 on the pressure changes at the top and bottom of the wing 30, the top plate 32 in this application is a curvature-adjustable structure. Figure 1As shown, the wing 30 includes an upper top plate 32 and a lower bottom plate 31, and the upper top plate 32 is an elastic steel plate; there is a hollow chamber between the upper top plate 32 and the lower bottom plate 31, and a transparent tube 33 fixed to the lower bottom plate 31 and distributed vertically is arranged in the hollow chamber, and a transparent sleeve 35 is slidably sleeved on the transparent tube 33, and the transparent sleeve 35 and the inner cavity of the transparent tube 33 together form an airflow channel 39; the transparent sleeve 35 is driven to rise and fall by an electric cylinder 36, and can push the upper top plate 32 to produce elastic deformation. In the present application, the airflow channel 39 adopts a retractable structure formed by a combination of a transparent tube 33 and a transparent sleeve 35. In addition, the curvature change of the upper top plate 32 is also achieved by the synchronous extension and retraction of the transparent sleeve 35. By driving the transparent sleeve 35 to rise and fall, the adaptive change between the curvature of the upper top plate 32 and the length of the airflow channel 39 can be achieved, thereby changing the pressure difference between the upper and lower surfaces of the wing 30, and realizing the adjustment of the lift force of the lightweight ball 34 in the airflow channel 39, thereby enhancing the diversity of the display of Bernoulli's principle.

[0032] Further, such as Figure 1 As shown, a push head 351 is fixed to the top of the transparent sleeve 35, and the middle part of the push head 351 has a through hole connected to the inner cavity of the transparent sleeve 35 and the top surface of the upper top plate 32. The push head 351 is fixed to the upper top plate 32 to ensure that when the transparent sleeve 35 is raised or lowered, the connection between the inner cavity of the transparent sleeve 35 and the upper surface of the wing 30 will not be misaligned. In addition, the top surface of the push head 351 is in an arc structure to fit with the bottom surface of the upper top plate 32 after being squeezed and elastically deformed by it, ensuring that the top of the upper top plate 32 can form a smooth arc structure after being squeezed and deformed.

[0033] On the basis of the above, if Figure 1 As shown, the outer periphery of the upper top plate 32 and the lower bottom plate 31 is wrapped with silicone cloth 38, which can keep the entire wing 30 intact after the upper top plate 32 is deformed, and further ensure the integrity of the gas streamlines formed by the airflow on the surfaces of the upper top plate 32 and the lower bottom plate 31.

[0034] On the basis of the above, if Figure 4 As shown, the wing 30 also includes transparent side panels 37 arranged on both sides of the upper top plate 32 and the lower bottom plate 31, the transparent side panels 37 are fixed to the lower bottom plate 31, and the inner wall of the transparent side panels 37 is in contact with the upper top plate 32. In this embodiment, the upper top plate 32 and the lower bottom plate 31 are blocked on both sides by the transparent side panels 37, so as to ensure that the airflow channel 39 is visible and prevent the airflow from entering the inner cavity of the wing 30 from both sides of the upper top plate 32 and the lower bottom plate 31 to form a turbulent flow. In addition, the transparent side panels 37 are installed in a manner that the inner wall is in contact with the upper top plate 32. When the upper top plate 32 is deformed, the upper top plate 32 and the transparent side panels 37 are slidably matched, and the deformation of the upper top plate 32 will not be hindered.

[0035] On the basis of the above, if Figure 3As shown, the cabinet 10 also includes a cabinet 10, a mounting groove 12 is provided on the front wall of the cabinet 10, a tempered glass 11 is installed at the notch of the mounting groove 12, a fan 40 and a wing 30 are both installed in the mounting groove 12, and an atomizer 60 is also provided between the fan 40 and the wing 30. In this embodiment, the atomizer 60 is provided to facilitate intuitive display of the streamline of the airflow outside the wing 30. In addition, the wing 30, the atomizer 60 and the fan 40 are arranged in the cabinet 10, so that the demonstration process is less affected by external wind energy.

[0036] Further, such as Figure 3 As shown, the interior of the mounting groove 12 is provided with a rectifier 50 connected to the outside of the cabinet 10, and the rectifier 50 is arranged on the side of the wing 30 away from the end of the fan 40. The rectifier 50 adopts the rectifier grid in the prior art. Since the airflow tends to become chaotic at the rear end of the wing 30, the rectifier 50 is arranged at the rear end of the wing 30 so that the airflow can maintain a parallel airflow direction when it goes out from the rear air outlet; it ensures that the airflow in the entire interval from the air outlet of the fan 40 to the air outlet outside the cabinet 10 maintains an orderly parallel airflow, avoiding the chaotic airflow at the rear end that causes the overall demonstration experiment to fail.

[0037] On the basis of the above, if Figure 3 and Figure 4 As shown, the wing 30 is rotatably connected to the cabinet 10 via a horizontal rotating shaft, the horizontal rotating shaft is perpendicular to the length direction of the wing 30, and the rotation angle of the wing 30 is adjustable. With the adjustable rotation angle structure of the wing 30, the operator can further demonstrate the Bernoulli principle by rotating the wing 30 and observing the airflow direction on the upper and lower sides of the wing 30 and the motion state of the ball in the wing 30. In this embodiment, the rotation angle adjustment of the wing 30 can be achieved by using a motor with a locking function, or by a latch structure.

[0038] Further, to increase the interactivity between the angle adjustment of the wing 30 and the operator, as Figure 3 and Figure 4 As shown, the wing 30 is located on both sides of the horizontal shaft with equal weight, so that the wing 30 remains horizontal in a normal state, and the end of the wing 30 can be aligned with the fan 40 in a normal state, ensuring that the fan 40 can form a stable airflow at the top and bottom of the wing 30 in the initial state. In addition, a handle 371 penetrating the tempered glass 11 is fixed on the wing 30, and an arc-shaped long hole 111 for the handle 371 to slide is provided on the tempered glass 11, which is convenient for the operator to manually operate the angle of the wing 30, thereby improving the interactivity of the demonstration device.

[0039] like Figure 3As shown, a display screen 20 is provided at the bottom of the installation slot 12. When the device is not started, the display screen 20 plays the popular science video of Bernoulli's principle in a loop to deepen the viewer's understanding of Bernoulli's principle.

[0040] It is worth mentioning that in order to further show the streamline conditions of the airflow on the top surface of the wing 30 and the ground, in the present application, the display screen 20 also has the function of displaying the force streamline diagram of the wing 30 in real time, thereby further deepening the viewer's understanding of the Bernoulli principle.

[0041] The specific steps of displaying the force flow line diagram on the display screen 20 are as follows:

[0042] The shape profile parameters of the wing 30 in the initial state and the airflow speed on the top surface of the wing 30 and the ground are obtained, and a simulation model of the wing 30 is established in the computer. The real airflow direction is simulated by the simulation model to form a force streamline diagram of the wing 30 and display it on the display screen 20.

[0043] When the audience rotates the wing 30, the rotation angle of the wing 30 is obtained, and the angle can be obtained through an encoder; according to the obtained rotation angle information, the computer synchronously rotates the simulation model to the same angle, and then simulates the airflow direction to form a force streamline diagram of the wing 30, which is displayed on the display screen 20.

[0044] When the audience adjusts the curvature of the wing 30, since the top curve of the wing 30 is relatively complex, in this demonstration device, the curve of the upper top plate 32 on the wing 30 is simplified to the existing catenary equation for simulation. By establishing a catenary equation algorithm in the computer, when the electric cylinder 36 moves upward, the distance the electric cylinder 36 moves upward is obtained, so as to determine the distance the vertex of the top surface curve of the upper top plate 32 moves upward, and then calculate the curvature change of the upper side curve of the upper top plate 32, and then synchronously update the changed curvature of the curve to the simulation model in the computer, and then output the changed airflow direction and force streamline diagram of the wing 30, and display it on the display screen 20.

[0045] Of course, it is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, but also includes the same or similar structures that can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any reference numerals in the claims should not be regarded as limiting the claims involved.

[0046] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0047] The techniques, shapes, and structural parts not described in detail in the present invention are all well-known techniques.

Claims

1. A Bernoulli visualization demonstration device, comprising a wing (30) arranged horizontally in a normal state and a fan (40) arranged beside one end of the wing (30), characterized in that: A vertically distributed airflow channel (39) is arranged inside the wing (30), the airflow channel (39) can be seen from the outside of the wing (30), and the airflow channel (39) is connected to both the top surface and the bottom surface of the wing (30). A light ball (34) is arranged in the inner cavity of the airflow channel (39), and the light ball (34) can move upward under the pressure difference between the top surface and the bottom surface of the wing (30).

2. A Bernoulli visualization demonstration device according to claim 1, characterized in that: The wing (30) comprises an upper top plate (32) and a lower bottom plate (31), wherein the upper top plate (32) is an elastic steel plate, and a hollow chamber is provided between the upper top plate (32) and the lower bottom plate (31), wherein a transparent tube (33) fixed to the lower bottom plate (31) and arranged in a vertical distribution is provided in the hollow chamber, wherein a transparent sleeve (35) is slidably sleeved on the transparent tube (33), wherein the inner cavity of the transparent sleeve (35) and the transparent tube (33) jointly form an air flow channel (39), and the transparent sleeve (35) is driven to rise and fall by an electric cylinder (36), and can push the upper top plate (32) to generate elastic deformation.

3. A Bernoulli visualization demonstration device according to claim 2, characterized in that: A push head (351) is fixed on the top of the transparent sleeve (35), the push head (351) is fixed to the upper top plate (32), and the top surface of the push head (351) is in an arc structure so as to fit with the bottom surface of the upper top plate (32) after being squeezed and elastically deformed by the push head (351), and the middle part of the push head (351) has a through hole connected to the inner cavity of the transparent sleeve (35) and the top surface of the upper top plate (32).

4. A Bernoulli visualization demonstration device according to claim 2, characterized in that: The outer peripheries of the upper top plate (32) and the lower bottom plate (31) are wrapped with silica gel cloth (38).

5. A Bernoulli visualization demonstration device according to claim 2, characterized in that: The wing (30) further comprises transparent side panels (37) arranged on both sides of the upper top panel (32) and the lower bottom panel (31); the transparent side panels (37) are fixed to the lower bottom panel (31); and the inner wall of the transparent side panels (37) is in close contact with the upper top panel (32).

6. A Bernoulli visualization demonstration device according to claim 1 or 2 or 3 or 4 or 5, characterized in that: The cabinet (10) further comprises a cabinet body (10), wherein a mounting groove (12) is arranged on the front wall of the cabinet body (10), a tempered glass (11) is installed at the notch of the mounting groove (12), a fan (40) and a wing (30) are both installed in the mounting groove (12), and an atomizer (60) is also arranged between the fan (40) and the wing (30).

7. A Bernoulli visualization demonstration device according to claim 6, characterized in that: A rectifier (50) connected to the outside of the cabinet (10) is arranged inside the installation groove (12), and the rectifier (50) is arranged on the side of the wing (30) away from one end of the fan (40).

8. A Bernoulli visualization demonstration device according to claim 6, characterized in that: The wing (30) is rotatably connected to the cabinet (10) via a horizontal rotation axis, the horizontal rotation axis is perpendicular to the length direction of the wing (30), and the rotation angle of the wing (30) is adjustable.

9. A Bernoulli visualization demonstration device according to claim 8, characterized in that: The wings (30) are located on both sides of the horizontal rotation axis and have equal weight, so that the wings (30) can remain horizontal in a normal state. A turning handle (371) penetrating the tempered glass (11) is fixed on the wing (30), and an arc-shaped long hole (111) for the turning handle (371) to slide is provided on the tempered glass (11).

10. The Bernoulli visualization demonstration device according to claim 6, characterized in that: A display screen (20) is provided at the bottom of the installation groove (12).

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