Method for measuring propagation starting wind speed of solanum rostratum plants by using wind tunnel

Abstract

The invention belongs to the technical field of wind-rolling plant starting wind speed measurement, and particularly relates to a method for measuring the propagation starting wind speed of solanum rostratum plants through a wind tunnel. The method comprises the following steps: (1) selecting a wind tunnel which is low in speed, large in section and stable and adjustable in wind speed; (2) selecting plastic simulation plants with different heights, and simulating a vegetation underlying surface; (3) simulating vegetation underlying surfaces with different density, height and coverage characteristics; (4) configuring a wind speed measuring device; and (5) selecting typical solanum rostratum plants, and measuring the average starting wind speed of the solanum rostratum plants on different underlying surfaces. Based on the wind propagation principle of the wind rolling plants, the starting wind speed of the solanum rostratum plants on different simulated underlying surfaces is measured through the wind tunnel, the principle is simple, measurement is accurate, and theoretical support is provided for prevention and control of the solanum rostratum.

Description

Technical Field

[0001] The invention belongs to the technical field of wind-rolling plant startup wind speed measurement, and particularly relates to a method for measuring the propagation startup wind speed of Solanum serrata plants by using a wind tunnel. Background Art

[0002] The alien invasive plant Solanum serratum is an annual weed with extremely strong invasiveness. After invasion, it competes with crops and local plants for resources such as light, water, and fertilizer, inhibits plant growth, and affects the yield of food and cash crops. Studies have shown that one of the main ways of propagation of Solanum serratum is wind rolling. It is reported that when the seeds of Solanum serratum mature, the plants break and roll under the action of wind. The seeds fall from the plants during the rolling process, and the seeds are spread by the wind rolling movement of the plants. The starting wind speed of the broken plant is the lowest wind speed at which it starts to move on the surface. Only when the wind speed exceeds the starting wind speed, the plant will roll and spread at a certain speed. Solanum serratum grows in grasslands, pastures, deserts and other habitats with low and open vegetation, so the starting wind speed of Solanum serratum is affected by the vegetation structure (height and coverage). Moreover, in the natural environment, the wind speed and direction in the field are unstable, and it is very difficult to measure the starting wind speed of Solanum serratum in different types of vegetation environments. Compared with field tests, wind tunnel simulation tests have the advantage of controllable wind conditions. Moreover, in large-scale wind tunnels, simulations of different types of vegetation structures can meet the physical similarity conditions of geometric similarity, motion similarity, and dynamic similarity with the actual wind propagation process in the field. Using this wind tunnel, vegetation of different heights and coverages was simulated, and a method for measuring the starting wind speed of Solanum serratum plants under different vegetation conditions was proposed, which is of great significance for the formulation of strategies for the prevention and control of the spread of Solanum serratum. Summary of the invention

[0003] In view of the problem that wind speed and direction are difficult to control in the wild, the purpose of the present invention is to provide a method for measuring the starting wind speed of Solanum spinulosa plants using a wind tunnel. This method overcomes the interference of complex outdoor environments and the measurement results are accurate and reliable.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] The present invention provides a method for measuring the wind speed of Solanum serrata plant propagation start-up by using a wind tunnel, comprising the following steps:

[0006] (1) Select a wind tunnel;

[0007] (2) Selecting plastic simulated plants;

[0008] (3) Laying plastic simulated plants in the wind tunnel to simulate the underlying vegetation surface;

[0009] (4) Select an anemometer;

[0010] (5) Determine the starting wind speed of Solanum spinulosa plants.

[0011] In a possible implementation, the wind tunnel includes a wind tunnel body and a wind source disposed at the front end of the wind tunnel body, and the wind source is used to provide low-speed wind into the wind tunnel body, and the wind volume is adjustable.

[0012] In a possible implementation, the plastic simulated plants are plastic simulated plants of different heights to simulate different vegetation underlying surfaces.

[0013] In one possible implementation, the vegetation underlying surface is a combination of plastic simulated plants of different heights to simulate a vegetation underlying surface with different density, height and coverage characteristics.

[0014] In a possible implementation, the wind speed measuring device is an anemometer capable of accurately measuring wind speed.

[0015] In a possible implementation, in step (5), the process of determining the startup wind speed of the Solanum serrata plant comprises the following steps:

[0016] (1) Selection of Solanum serrata plants;

[0017] (2) Wind speed measurement of a single Solanum serrata plant;

[0018] (3) Average starting wind speed measurement.

[0019] In a possible implementation, the Solanum nigrum calyx plants are selected by selecting five Solanum nigrum calyx plants with intact branches in the wild.

[0020] In a possible implementation, the method for measuring the wind speed of a single Solanum serratum plant is to place a single Solanum serratum plant at the center of different vegetation underlying surfaces in a wind tunnel test section, turn on the wind tunnel motor, and adjust the wind speed from 0 ms to -1 Start to increase gradually and observe the anemometer reading when the Solanum spinulosa plant starts.

[0021] In one possible implementation, the average starting wind speed determination method is to measure the starting wind speeds of five Solanum spinulosa plants on a vegetation underlying surface, calculate the average value as the starting wind speed of the plants on the vegetation underlying surface, and then repeat the measurement process on other vegetation underlying surfaces to obtain the starting wind speeds of the Solanum spinulosa plants on different vegetation underlying surfaces.

[0022] The advantages and beneficial effects of the present invention are as follows: the present invention is based on the wind propagation principle of wind-rolling plants, and utilizes a wind tunnel to measure the starting wind speed of Solanum arabinoides plants on different simulated underlying surfaces. The principle is simple and the measurement is accurate, providing theoretical support for the prevention and control of Solanum arabinoides.

[0023] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0024] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0026] Figure 1 The present invention is a schematic diagram of the principle of a method for measuring the propagation start wind speed of Solanum spinulosa plants using a wind tunnel.

[0027] In the figure: 1 is the wind tunnel body, 2 is the test section, 3 is the vegetation underlying surface, 4 is the Solanum spinulosa plant, 5 is the Pitot tube, and 6 is the differential pressure transmitter. DETAILED DESCRIPTION

[0028] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0030] See also Figure 1 As shown, an embodiment of the present invention provides a method for measuring the wind speed of Solanum serrata plant propagation start-up using a wind tunnel, comprising the following steps:

[0031] (1) Select a wind tunnel;

[0032] (2) Selecting plastic simulated plants;

[0033] (3) Laying plastic simulated plants in the wind tunnel to simulate the vegetation underlying surface 3;

[0034] (4) Select an anemometer;

[0035] (5) Determine the starting wind speed of Solanum nigrum plant 4.

[0036] In an embodiment of the present invention, the wind tunnel includes a wind tunnel body 1 and a wind source disposed at the head end of the wind tunnel body 1, the wind source is used to provide low-speed wind into the wind tunnel body 1, and the wind volume is adjustable. The vegetation underlying surface 3 is laid at the test section 2 of the wind tunnel body 1. Therefore, the wind tunnel has the characteristics of large cross-section, low speed, stable and adjustable wind speed.

[0037] In the embodiment of the present invention, the plastic simulated plants are plastic simulated plants of different heights, which are used to simulate different vegetation underlying surfaces 3. The vegetation underlying surface 3 is a combination of plastic simulated plants of different heights, which simulates vegetation underlying surfaces 3 with different density, height and coverage characteristics, such as bare land, desert grassland, typical grassland and meadow grassland underlying surface.

[0038] Specifically, the wind speed measuring device is an anemometer capable of accurately measuring wind speed, and related supporting equipment; the wind source adopts a fan.

[0039] In step (5), the process of determining the wind speed at which the Solanum sphaerocephalum plant 4 starts up comprises the following steps:

[0040] (1) Selecting Solanum nigrum calyx plants; specifically, selecting Solanum nigrum calyx plants is to select five typical Solanum nigrum calyx plants with intact branches in the wild;

[0041] (2) Wind speed measurement of a single Solanum serrata plant;

[0042] (3) Average starting wind speed measurement.

[0043] Specifically, the method for measuring the wind speed of a single Solanum serratum plant is to place a single Solanum serratum plant 4 at the center of different vegetation underlying surfaces 3 in the wind tunnel test section, turn on the wind tunnel motor, and make the wind speed change from 0 ms to 1 ms. -1 Start to increase gradually and observe the anemometer measurement value when Solanum serrata plant 4 is started.

[0044] Specifically, the method for determining the average starting wind speed is to measure the starting wind speeds of five Solanum spinulosa plants 4 on a vegetation underlying surface 3 respectively, calculate the average value, and use it as the starting wind speed of the plants on the vegetation underlying surface 3; then repeat the measurement process on other vegetation underlying surfaces 3 respectively to obtain the starting wind speeds of the Solanum spinulosa plants 4 on different vegetation underlying surfaces 3.

[0045] Embodiment 1

[0046] (1) Select a wind tunnel

[0047] In this embodiment, the wind tunnel adopts patent number ZL201310755608.0, and the invention name is a portable environmental wind tunnel that can adapt to the undulating terrain in the wild. It is a low-speed open wind tunnel with a square cross-section, 2m high, 2m wide, and a total length of 20m. It solves the problem of physical similarity of the test. The wind speed at the center of the wind tunnel cross-section can reach up to 14m s -1 The airflow stability coefficient of the wind tunnel 10m away from the fan is <4%, the lateral unevenness is <7%, and the turbulence is about 6%. A test measurement section is set up in the wind tunnel space 10 to 20m away from the fan. Therefore, the wind tunnel can meet the requirements for measuring the starting wind speed of wind propagation of Solanum nigrum plants.

[0048] (2) Select plastic simulated plants

[0049] The vegetation structure of desert steppe, typical steppe and meadow steppe is simulated by using three kinds of simulated grass combinations of low, medium and high heights. The height of a single low grass plant is 15cm and the projection area of ​​a single plant is 160cm. 2 ; Medium height grass height 50cm, single plant projection area 220cm 2 ; Tall grass height 70cm, single plant projection area 720cm 2 .

[0050] (3) Setting up vegetation underlying surface

[0051] Bare land: Bare land has no vegetation and the ground is covered with wind-blown sand to simulate mobile sand dunes;

[0052] Desert steppe: low grass plant density is 12 plants m -2 , with an average height of 15 cm and a vegetation cover of about 20%;

[0053] Typical grassland: low grass plant density is 12 plants m -2 , medium height grass density is 9 plants m -2 The vegetation coverage is about 40%, the average height is 30 cm, and the average plant density is 21 plants m -2 ;

[0054] Meadow grassland: low grass plant density is 20 plants m -2 , medium height grass density is 20 plants m -2 , the density of tall grass is 5 plants m -2 The vegetation coverage is about 60%, the average height is 40 cm, and the average plant density is 45 plants m -2 .

[0055] Different vegetation underlying surfaces 3 are set in the test section 10m away from the wind turbine. The length of the vegetation underlying surface 3 is set to 5m. According to different vegetation structure configuration schemes, plastic plants are first fixed on cardboard and buried in the sand of the test section, and the burial depth is adjusted to meet the test requirements.

[0056] (4) Determine wind speed

[0057] The wind speed in the wind tunnel was measured using a pitot tube 5 and a differential pressure transmitter 6 (160-96, Dwyer Instruments, Inc., IN). The pitot tube 5 was fixed to the top of the wind tunnel body 1, with the inlet set at the center of the cross section of the wind tunnel body 1 (1 m from the ground and the wind tunnel wall), and the top was connected to the differential pressure transmitter 6 to read the wind speed.

[0058] (5) Determination of the starting wind speed of Solanum serrata

[0059] ① Place the Solanum nigrum plant 4 at the center of the different vegetation underlying surfaces 3, turn on the fan motor, and increase the wind speed from 0 ms to -1 Start to increase gradually, with a minimum increase of 1m s -1 ; ② When the Solanum nigrum plant 4 was observed to roll 0.5 circles, the wind speed measured by the differential pressure transmitter 6 was the starting wind speed of the wind propagation of the plant; ③ Five Solanum nigrum plants 4 were taken to measure the starting wind speed of the Solanum nigrum plants 4 in simulated bare land, desert steppe, typical steppe and meadow steppe, and the average speed of the 5 measurements was calculated.

[0060] The present invention is based on the wind propagation principle of wind-rolling plants, and uses a wind tunnel to measure the starting wind speed of Solanum rostratum plants on different simulated vegetation underlying surfaces. The principle is simple and the measurement is accurate, providing theoretical support for the prevention and control of Solanum rostratum.

[0061] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for measuring the wind speed of Solanum serrata plant propagation using a wind tunnel, characterized in that: The following steps are involved: (1) Select a wind tunnel; (2) Selecting plastic simulated plants; (3) Laying plastic simulated plants in the wind tunnel to simulate the underlying vegetation surface; (4) Select an anemometer; (5) Determine the starting wind speed of Solanum spinulosa plants.

2. The method for measuring the wind speed of Solanum serrata plant propagation using a wind tunnel according to claim 1, characterized in that: The wind tunnel comprises a wind tunnel body and a wind source arranged at the front end of the wind tunnel body. The wind source is used to provide low-speed wind into the wind tunnel body, and the wind volume is adjustable.

3. The method for measuring the wind speed of Solanum serrata plant propagation using a wind tunnel according to claim 1, characterized in that: The plastic simulated plants are plastic simulated plants of different heights, which are used to simulate different vegetation underlying surfaces.

4. The method for measuring the wind speed of Solanum serrata plant propagation using a wind tunnel according to claim 3, characterized in that: The vegetation underlying surface is a combination of plastic simulated plants of different heights to simulate a vegetation underlying surface with different density, height and coverage characteristics.

5. The method for measuring the wind speed of Solanum serrata plant propagation using a wind tunnel according to claim 1, characterized in that: The wind speed measuring device is an anemometer capable of accurately measuring wind speed.

6. The method for measuring the wind speed of Solanum serrata plant propagation using a wind tunnel according to claim 1, characterized in that: In step (5), the process of determining the starting wind speed of the Solanum serrata plant comprises the following steps: (1) Selection of Solanum serrata plants; (2) Wind speed measurement of a single Solanum serrata plant at startup; (3) Average starting wind speed measurement.

7. The method for measuring the wind speed of Solanum serrata plant propagation using a wind tunnel according to claim 6, characterized in that: The Solanum nigrum calyx plants are selected by selecting five Solanum nigrum calyx plants with intact branches in the wild.

8. The method for measuring the wind speed of Solanum serrata plant propagation using a wind tunnel according to claim 6, characterized in that: The method for measuring the starting wind speed of a single Solanum serratum plant is to place a single Solanum serratum plant at the center of different vegetation underlying surfaces in a wind tunnel test section, turn on the wind tunnel motor, and adjust the wind speed from 0 ms to 10 ms. -1 Start to increase gradually and observe the anemometer reading when the Solanum spinulosa plant starts.

9. The method for measuring the wind speed of Solanum serrata plant propagation using a wind tunnel according to claim 6, characterized in that: The average starting wind speed determination method is to respectively determine the starting wind speeds of five Solanum nigrum plants on a vegetation underlying surface, calculate the average value as the starting wind speed of the plants on the vegetation underlying surface, and then repeat the determination process on other vegetation underlying surfaces to obtain the starting wind speeds of the Solanum nigrum plants on different vegetation underlying surfaces.

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