A method of cleaning a coupling flow field

Abstract

The application provides a method for cleaning a flow field, which comprises driving garbage by blowing air flow to the surface of a cleaning area, and then carrying the garbage away from the surface of the cleaning area by absorbing air flow. The blowing air flow is composed of a main blowing air flow and two side auxiliary blowing air flows. The main blowing air flow is generated by one or more parallel air flows. The direction of the main blowing air flow is consistent with the direction of the absorbing air flow. The two side auxiliary blowing air flows have an angle of approaching the middle part from the tail part. The air flow generated by the main blowing air flow and the two side auxiliary blowing air flows is consistent with the direction of the absorbing air flow. The garbage carried by the multi-air-flow blowing air flow is absorbed by the absorbing air flow. The application can fully exert the driving effect of the main blowing air flow on the garbage in the width direction, reduce the phenomenon that the garbage escapes to the two sides due to the divergence of the main blowing air flow at the tail part, and reduce the secondary dust phenomenon generated in the air. The method is also suitable for surface cleaning of vertical surfaces, top surfaces, irregular surfaces and uneven surfaces, and can guarantee high cleaning efficiency.

Description

Technical Field

[0001] This invention relates to the field of pneumatic cleaning technology for environmental sanitation, and particularly to a cleaning method coupled with a flow field. Background Technology

[0002] To effectively clean and maintain the environment, sweeping surfaces such as road surfaces and appliance surfaces is a common cleaning method. Currently, the main sweeping methods used domestically and internationally include combined disc brush-spraying-vacuuming, purely pneumatic, combined sweeping and vacuuming, and vacuum cleaning, as detailed below:

[0003] Disc brush-sprinkling-vacuuming combined method: This is a common method for cleaning road surfaces. It cleans up road debris and dust by using a disc brush to sweep the road, sprinkling water to reduce dust, and vacuuming with negative pressure. However, this method has the following problems: (1) The vacuum nozzle can only achieve a good cleaning effect when it is close to the ground. When the road surface is uneven, the cleaning effect is often greatly reduced; (2) Some dust will stick to the ground after it comes into contact with water and is difficult to be sucked away by the nozzle. In cold regions, the water sprayed out may freeze and make the road surface too slippery; (3) The disc brush is easy to wear and needs to be replaced frequently.

[0004] Pure pneumatic cleaning: This cleaning method mainly includes pure suction and a combination of blowing and suction. Pure suction uses only the negative pressure at the suction port to draw garbage into the garbage bin, but it is only suitable for cleaning garbage near the suction port. For garbage slightly further away, the negative pressure quickly weakens, making it difficult to clean. For larger garbage, it is difficult to enter the suction port, making it difficult to clean. The combined blowing and suction method uses the positive pressure at the blowing port to blow garbage to the vicinity of the suction port, and the negative pressure at the suction port assists in drawing the garbage into the garbage bin. Although it can increase the cleaning area and cleaning efficiency compared to pure suction, existing reports do not mention how to prevent secondary dust from being generated to both sides, how to adapt to uneven surfaces, or how to use effective flow field evaluation indicators to couple multiple airflows. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of the aforementioned background technology by providing a highly efficient cleaning method based on coupled flow fields, which minimizes secondary dust generation and is suitable for uneven surfaces.

[0006] To achieve the above objectives, the present invention provides a cleaning method with coupled flow fields. A blowing airflow is directed at the surface of the cleaning area to drive the debris, and then an absorbing airflow carries the debris away from the surface of the cleaning area, thus cleaning the debris from the surface of the cleaning area. The blowing airflow consists of a main blowing airflow and auxiliary blowing airflows on both sides. The main blowing airflow is generated by one or more parallel airflows, and its direction is consistent with the direction of the absorbing airflow. The auxiliary blowing airflows on both sides have an angle at their tails converging towards the center, and combine with the airflows diverging to both sides from the main blowing airflow to form a flow consistent with the direction of the absorbing airflow. The debris carried by the multiple blowing airflows is received by the absorbing airflow.

[0007] Furthermore, the main blowing airflow and the auxiliary blowing airflows on both sides should satisfy... W Bmi W represents the width of the i-th main airflow, with a total of I and W. Bhj Let J represent the width of the j-th auxiliary airflow, with a total of J and a minimum value of 2.

[0008] Furthermore, the auxiliary airflow on both sides needs to meet the following requirements. This indicates the speed at which the main airflow diverges outwards. Indicates the velocity of the auxiliary blowing airflow. This indicates the speed at which the airflow is absorbed.

[0009] Furthermore, the surface adaptation requirements for airflow include: O S >O B O S Indicates the opening degree of the absorption airflow, O B This indicates the opening degree of the blowing airflow.

[0010] Furthermore, the surface adaptation requirements for airflow also include: O Bd >(1+γ / 45°)R a O Bd R is the thickness of the airflow covering the surface of the cleaning area in the blowing direction, γ is the angle between the airflow that most significantly bends backward and upward after encountering the protruding obstacle and the surface of the cleaning area, γ∈[0, 90°], R a The height of the bulge encountered by the most obvious upward and backward folding airflow.

[0011] Furthermore, the first flow field evaluation index for the cleaning method is the secondary dust re-entrainment rate: η1=(1-Q SB / Q B )∈[0,1], representing the degree of secondary dust emission; the smaller the value, the better. The ideal value of 0 represents no secondary dust emission. Q SB The flow rate of the blowing airflow is changed to the absorption airflow; Q B The flow rate of the blowing air.

[0012] Furthermore, the second flow field evaluation index for the cleaning method is the energy consumption cleaning rate: This represents the effect of airflow on removing debris per unit power, v. Ak This represents the velocity of the k-th position relative to the cleaning area, with a total of K positions, v pmax This indicates the maximum starting speed of the waste disposal unit, and P represents the total airflow power input to the cleaning area. p s To absorb the relative pressure at the airflow inlet, p B Q represents the relative pressure at the outlet of the blowing airflow. S To absorb the airflow, Q B The flow rate of the blowing airflow is ρ, the gas density is v. S To absorb the airflow velocity, v B The velocity of the blowing airflow.

[0013] The above-described solution of the present invention has the following beneficial effects:

[0014] The cleaning method with coupled flow field provided by this invention, through the coupling of multiple airflows including the main airflow and the auxiliary airflows on both sides, can give full play to the driving effect of the main airflow on the garbage in terms of width, reduce the phenomenon of garbage escaping to both sides due to the divergence of the main airflow at the tail, and reduce the phenomenon of secondary dust generation into the air. Moreover, since the flow field evaluation index of secondary dust generation rate and energy consumption cleaning rate is adopted, it is beneficial to improve the cleaning efficiency through flow field control. This method is also applicable to surface cleaning of vertical surfaces, top surfaces, uneven surfaces, etc. In addition, this method does not require the use of water resources, can achieve non-contact cleaning, and the wear on the cleaning surface is much less than that of traditional solutions. It can avoid problems such as corrosion, water waste and dust adhesion to the ground caused by water washing.

[0015] Other beneficial effects of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the airflow before it enters the surface of the cleaning area according to the present invention;

[0017] Figure 2 This is a schematic diagram of the airflow in the coupled flow field of the present invention on the front and rear symmetry planes;

[0018] Figure 3 This is a velocity vector diagram of the surface of the cleaned area in the flow field simulation of this invention;

[0019] Figure 4 This is a pressure cloud map at the symmetry plane of the cleaned area in the flow field simulation of this invention;

[0020] Figure 5This is a particle trajectory diagram of the cleaning zone in the simulation of this invention. Detailed Implementation

[0021] The following specific examples illustrate the implementation of this disclosure. Those skilled in the art can easily understand other advantages and effects of this disclosure from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. This disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this disclosure. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0022] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this disclosure, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0023] It should also be noted that the illustrations provided in the following embodiments are merely schematic representations of the basic concept of this disclosure. The illustrations only show components relevant to this disclosure and are not drawn according to the actual number, shape, and size of components in implementation. In actual implementation, the type, quantity, and proportion of each component can be arbitrarily changed, and the component layout may be more complex. Furthermore, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that the described aspects can be practiced without these specific details.

[0024] like Figure 1 , Figure 2 As shown, embodiments of the present invention provide a cleaning method with coupled flow fields. One or more parallel blowing airflows are directed at the surface of the cleaning area to drive the debris, and then an absorbing airflow carries the debris away from the surface of the cleaning area, thereby achieving debris cleaning of the surface of the cleaning area. The cleaning requirements include three aspects: the basic combination of airflows, the surface adaptation requirements of the airflows, and flow field evaluation.

[0025] Specifically, the basic requirements for airflow combination are: the blowing airflow consists of one or more main blowing airflows in the same direction and auxiliary blowing airflows on both sides, and should meet the following requirements. To ensure that the main airflow fully exerts its width-based effect on repelling the waste, W Bmi W represents the width of the i-th main airflow, with a total of I and W. Bhj This represents the width of the j-th auxiliary airflow. The total number of auxiliary airflows is J, which is usually an even number, with a minimum value of 2.

[0026] At the same time, the auxiliary airflow on both sides should also meet the following requirements. To ensure that the garbage does not escape to the sides due to the main airflow dissipating at the tail end, among other things, This indicates the speed at which the main airflow diverges outwards. Indicates the velocity of the auxiliary blowing airflow. This indicates the speed at which the airflow is absorbed.

[0027] In this embodiment, the surface adaptation requirement for the airflow is: O S >O B To ensure that the absorber airflow receives as much blower airflow as possible, where O S Indicates the opening degree of the absorption airflow, O B This indicates the opening degree of the blowing airflow.

[0028] Meanwhile, the surface adaptation requirements for airflow also include: O Bd >(1+γ / 45°)R a To ensure that the airflow can cover the surface protrusions of the cleaning area and become an absorption airflow, wherein, O Bd R is the thickness of the airflow covering the surface of the cleaning area in the blowing direction, γ is the angle between the airflow that most significantly bends backward and upward after encountering the protruding obstacle and the surface of the cleaning area, γ∈[0, 90°], R a This refers to the height of the protrusion encountered by the most prominent upward-curving airflow. The larger the angle of the upward-curving airflow, the greater the velocity component perpendicular to the surface of the cleaning area, making it more difficult for the airflow to become an absorbent flow. Therefore, an airflow exceeding the height of the protrusion is needed to combine into an absorbent flow. It should be noted that the most difficult state for the airflow to become an absorbent flow is when it is entirely upward-curving and perpendicular to the surface of the cleaning area.

[0029] The flow field evaluation index for cleaning effect includes secondary dust re-entrainment rate: η1=(1-Q SB / Q B )∈[0,1], indicating that the degree of secondary dust is evaluated using flow field indices, with an ideal value of 0, meaning no secondary dust. Where, Q SB The flow rate of the blowing airflow is changed to the absorption airflow; Q B The flow rate of the blowing air.

[0030] In this embodiment, the flow field evaluation index also includes energy consumption cleaning rate: This represents the effect of the flow field on debris removal under unit power, where v Ak This represents the velocity of the k-th position relative to the cleaning area, with a total of K positions, v pmax This indicates the maximum starting speed for free dust particles, gravel, and other debris; P represents the total airflow power input to the cleaning area. p s To absorb the relative pressure at the airflow inlet, p B Q represents the relative pressure at the outlet of the blowing airflow. S To absorb the airflow, Q B The flow rate of the blowing airflow is ρ, the gas density is v. S To absorb the airflow velocity, c B The velocity of the blowing airflow.

[0031] The following specific examples further illustrate this cleaning method:

[0032] Figure 1 As shown, the equipment involved in this cleaning method includes a suction nozzle 1 and three blow nozzles 2, which are installed in the middle area below the existing road sweeper. The blow nozzles 2 include a main blow nozzle 22 and two auxiliary blow nozzles 21 and 23. The airflow blown out by the main blow nozzle 22 is the main blowing airflow, and the airflow blown out by the auxiliary blow nozzles 21 and 23 is the auxiliary blowing airflow. Figure 1 In the diagram, dimension D represents the distance from the lower edge of the main blow nozzle 22 to the lower edge of the suction nozzle 1, which is the length of the cleaning area. The width of the cleaning area is the width W of the suction nozzle. s The corresponding area is cleaning zone 3. The suction nozzle 1 has a suction pipe at the end facing away from the cleaning surface, and the blow nozzle 2 has a blow pipe at the end facing away from the cleaning surface. The suction pipe connects the suction nozzle 1 to the exhaust device, and the blow pipe connects the blow nozzle 2 to the blower device. Corresponding drive mechanisms and control systems can be added to the blow nozzle 2 and suction nozzle 1 to adjust the angle and position of the nozzles, ensuring that the airflow blown from the blow nozzle is absorbed by the suction nozzle as much as possible. Without exceeding the maximum width limit of the road sweeper vehicle body, the suction nozzle width W... s The maximum value should be selected to maximize the width of the cleaning area. For uneven ground or large debris, the suction nozzle 1 and blow nozzle 2 are often positioned further off the ground than existing combined disc brush-sprinkler-vacuum or pure suction systems to ensure cleaning effectiveness, thus demonstrating adaptability to complex working conditions. The main blow nozzle 22 is parallel to the suction nozzle 1, and the auxiliary blow nozzles 21 and 23 are angled towards each other at the tail end to reduce the possibility of airflow leakage to the sides. The suction nozzle 1 and blow nozzle 2 are at a certain angle to the ground.

[0033] Since the auxiliary blowing airflow may disrupt the main blowing airflow and become an absorption airflow, the main nozzle width W bm1 It should be greater than the width W of the auxiliary nozzle. bh1 W bh2 The included angles β1 and β2 between the main blowing nozzle 22 and the auxiliary blowing nozzles 21 and 23 should not be too large. When the flow rate and velocity of the main blowing airflow are large, most of the dust particles can be pushed to the inlet of the suction nozzle 1. When the flow rate and velocity of the auxiliary blowing airflow are small, it can be combined with the airflow diverging at the tail of the main blowing airflow to form an absorption airflow.

[0034] Before the road sweeper begins its sweeping operation, the position parameters of the air nozzles are adjusted through the corresponding control system and drive device. Generally, the direction of the road sweeper's movement should be aligned with the direction of the airflow from nozzle 2 for optimal sweeping. If the directions are not aligned, the airflow speed from nozzle 2 should be relatively higher. The road sweeper's speed must be ensured not to significantly disrupt the sweeping effect of the coupled airflow. The airflow generated by the blowing device enters nozzle 2 through the blowing pipe and exits from the outlet of nozzle 2. The blowing airflow pushes the debris on the sweeping surface to the vicinity of the suction nozzle 1 inlet. During this pushing process, the airflow speed gradually decreases, but the minimum speed is still greater than the dust particle initiation speed. Simultaneously, the suction device starts working, generating negative pressure at the suction nozzle 1 inlet. Before the kinetic energy of the airflow from nozzle 2 dissipates, suction nozzle 1 draws the airflow and debris near its inlet into the dust collection device. Under the influence of the negative pressure at suction nozzle 1, the airflow speed also gradually increases. Figure 4 As shown.

[0035] To verify the cleaning effect of the road sweeping in this embodiment, a numerical model was established based on the structural dimensions of existing road sweepers for simulation, and the width W of the absorbed airflow was calculated. s The width W of the main airflow is 2500mm. bm1 The width W of the auxiliary blowing airflow is 1500mm. bh1 and W bh2 Both are 300mm, with an absorption airflow opening of O. S The opening of the blowing airflow is 130mm. B All are 120mm. The relative pressure at the outlet of the absorption airflow is -2300Pa, the velocity at the inlet of the blowing airflow is 12m / s, and the dust particles are injected from the surface of the cleaning area with an initial velocity of 0m / s. The cleaning effect of the invention is judged by the capture of particles at the outlet of the suction nozzle 1.

[0036] The airflow in this simulation is a low-speed flow with a Mach number less than 0.3. Therefore, the air is considered an incompressible gas, and the Realizable k-epsilon model is used to simulate the continuous phase, referring to the following two equations:

[0037]

[0038]

[0039] In the above formula, G k The term representing the generation of turbulent kinetic energy k due to the average velocity gradient, where v is the kinematic viscosity coefficient, and σ is the kinetic energy. k =1.0, σ ε =1.2, C2 = 1.9,

[0040] In the clean flow field, heat exchange is not considered, and the airflow follows the continuity equation and the momentum conservation equation. Therefore, the governing equations are established as follows:

[0041]

[0042]

[0043] In the above formula, ρ is the fluid density, t is time, v is the fluid velocity vector; p is the static pressure; τ ij g is the stress tensor; i and F i These are the gravitational volume force and the external volume force in the i-direction, respectively.

[0044] Since the volume fraction of dust particles is less than 10%, the DPM model is used to simulate the discrete phase. During the cleaning process, dust particles and airflow interact, so a two-way coupled simulation is employed. The finite volume method is used for numerical simulation, and the SIMPLE algorithm is used for steady-state solution. A second-order upwind scheme is used for spatial discretization. The number of iterations is set to 10,000, and the convergence criterion is that the residuals tend to a certain value.

[0045] Simulation results are as follows Figures 3-5 As shown. By Figure 3 It can be seen that the coupling effect between the blowing airflow and the absorbing airflow causes the airflow in the cleaning flow field to flow towards the absorbing airflow, which helps the airflow carry dust particles in the cleaning space to the absorbing airflow, where they are then sucked away. For example... Figure 4 As shown, the negative pressure created by the absorption airflow is much lower than standard atmospheric pressure, and the negative pressure area created by the absorption airflow can be close to the ground, effectively drawing in dust particles that move to the ground near the absorption airflow. Figure 5 As shown, under the coupling effect of the blowing airflow and the absorption airflow, most of the dust particles on the surface of the cleaning area are successfully activated, pushed to the area near the absorption airflow, and sucked away by the absorption airflow, indicating that the dust particle cleaning effect is good.

[0046] The following case further illustrates this point:

[0047] A suction nozzle 1 and three blowing nozzles 2 are installed at the end of the robotic arm. Similarly, the blowing nozzles 2 include a main blowing nozzle 22 and two auxiliary blowing nozzles 21 and 23, and the width of the main blowing nozzle is W. bm1 It should be greater than the width W of the auxiliary nozzle. bh1 W bh2 The main nozzle 22 blows out the main airflow, while the auxiliary nozzles 21 and 23 blow out the auxiliary airflow. The main airflow has a larger flow rate and velocity, while the auxiliary airflow has a smaller flow rate and velocity, ensuring that the auxiliary airflow does not disrupt the main airflow and become an absorption airflow. The area between the suction nozzle 1 and the nozzle 2 is the cleaning area. Each nozzle has a suction pipe or a blowing pipe at the end away from the cleaning surface. The suction pipe is used to connect the suction nozzle 1 to the exhaust device, and the blowing pipe is used to connect the nozzle 2 to the blowing device.

[0048] The operator first determines the cleaning area and path. Then, the system detects wind speed and pressure in the flow field and calculates flow field evaluation indicators. Based on these indicators, while ensuring the highest possible cleaning efficiency, the system dynamically adjusts the corresponding position and airflow parameters in real time. These parameters include the position parameters of suction nozzle 1 and air nozzle 2, as well as the airflow velocity of air nozzle 2 and the negative pressure of suction nozzle 1. The position parameters of suction nozzle 1 and air nozzle 2 are implemented through a robotic arm and position control system; the airflow parameters are implemented through an airflow control system. Furthermore, the system must ensure that the movement speed of the cleaning system relative to the ground does not affect the cleaning effect of the coupled flow field.

[0049] In this case, the robotic arm's flexibility and multi-degree-of-freedom movement enable it to perform more complex and diverse cleaning tasks, such as cleaning areas that are difficult to reach, including high places, confined spaces, and complex terrain. Furthermore, the robotic arm's end effector allows for coordinated operation of the suction nozzle 1 and the blowing nozzle 2, making the cleaning process more efficient and comprehensive, and adaptable to various cleaning scenarios such as industrial automation, warehousing and logistics, building maintenance, and transportation facilities.

[0050] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A cleaning method using coupled flow fields, comprising: a blowing airflow directed towards the surface of a cleaning area to drive debris removal; and an absorption airflow receiving the blowing airflow to carry the debris away from the surface of the cleaning area, thereby achieving debris removal from the surface of the cleaning area; characterized in that... The blowing airflow consists of a main blowing airflow and auxiliary blowing airflows on both sides. The main blowing airflow is generated by one or more parallel airflows. The direction of the main blowing airflow is the same as the direction of the absorption airflow. The auxiliary blowing airflows on both sides have an angle that converges towards the middle at the tail end. They combine with the airflows that diverge to both sides from the main blowing airflow to form a flow that is consistent with the direction of the absorption airflow. The garbage carried by the multiple blowing airflows is received by the absorption airflow.

2. The method for cleaning a coupled flow field according to claim 1, characterized in that, The main airflow and the auxiliary airflows on both sides should satisfy... W Bmi W represents the width of the i-th main airflow, with a total of I and W. bhj Let J represent the width of the j-th auxiliary airflow, with a total of J and a minimum value of 2.

3. The method for cleaning a coupled flow field according to claim 2, characterized in that, The auxiliary airflow on both sides must meet the following requirements This indicates the speed at which the main airflow diverges outwards. Indicates the velocity of the auxiliary blowing airflow. This indicates the speed at which the airflow is absorbed.

4. The method for cleaning a coupled flow field according to claim 1, characterized in that, Surface adaptation requirements for airflow include: O S >O B O S Indicates the opening degree of the absorption airflow, O B This indicates the opening degree of the blowing airflow.

5. The method for cleaning a coupled flow field according to claim 4, characterized in that, The surface adaptation requirements for airflow also include: O Bd >(1+γ / 45°)R a O Bd R is the thickness of the airflow covering the surface of the cleaning area in the blowing direction, γ is the angle between the airflow that most significantly bends backward and upward after encountering the protruding obstacle and the surface of the cleaning area, γ∈[0, 90°], R a The height of the bulge encountered by the most obvious upward and backward folding airflow.

6. The method for cleaning a coupled flow field according to claim 1, characterized in that, Secondary dust emission rate of the cleaning method: η1=(1-Q SB / Q B )∈[0,1], representing the degree of secondary dust, Q SB The flow rate of the blowing airflow is changed to the absorption airflow; Q B The flow rate of the blowing air.

7. The method for cleaning a coupled flow field according to claim 1, characterized in that, Energy consumption and cleaning efficiency of the cleaning method: This represents the effect of airflow on removing debris per unit power, v. Ak This represents the velocity of the k-th position relative to the cleaning area, with a total of K positions, v pmax This indicates the maximum starting speed of the waste disposal unit, and P represents the total airflow power input to the cleaning area. p s To absorb the relative pressure at the airflow inlet, p B Q represents the relative pressure at the outlet of the blowing airflow. S To absorb the airflow, Q B The flow rate of the blowing airflow is ρ, the gas density is v. S To absorb the airflow velocity, v B The velocity of the blowing airflow.

Images