Rainfall controller for rainfall simulation test

Abstract

A rainfall controller for a rainfall simulation test is characterized by being composed of a water supply system, a spraying system, a rainfall control system and a rainwater backflow system. The artificial rainfall simulation device is recyclable and movable, and the device is easy and convenient to operate, easy to disassemble and low in manufacturing cost. According to the device, three types of downward spraying type nozzles with different specifications are combined, and the rainfall can be controlled by controlling the pressure of the water conveying pipeline, opening and closing the nozzles with different types and adjusting the position of the canopy and the inclination angle of the water permeable plate, so that the artificial simulation rainfall process with different rainfall intensities and different durations is realized. According to the backflow system, rainwater sprayed out of the model box is collected through the curtain, rainwater which does not pass through the water permeable plate is gathered into the sedimentation tank through a gap between the inclined water permeable plate and the u-shaped water storage tank along the slope, the rainwater is filtered through the filter screen and then is pumped into the u-shaped water tank again through the backflow self-priming pump, and backflow recycling of the water is achieved.

Description

Technical Field

[0001] The present application belongs to the field of rainfall simulation test devices, and in particular relates to a rainfall controller used for rainfall simulation tests. Background Art

[0002] Soil erosion is one of the major problems worldwide, and rainfall is one of the important factors causing soil erosion on the ground and natural disasters in mountainous areas such as landslides, collapses, and mudslides. When using natural rainfall, it is often limited by time and geographical conditions, which brings great difficulties to the test work. In addition, when studying soil erosion, slope runoff, soil infiltration, etc., the research cycle using natural rainfall is long and is greatly affected by the environment, making it difficult to obtain ideal results. The method of artificial rainfall simulation can conveniently control the test process and shorten the test cycle. It is an ideal rainfall method to effectively use artificial rainfall simulation devices to carry out rainfall tests. It is not limited by time and space, can reproduce natural rainfall, can save a lot of manpower and material resources, and can repeat the test in a short period of time and shorten the test cycle. The artificial rainfall simulation method can make up for the research results that cannot be obtained under natural rainfall conditions in the short term, and can verify the research conclusions obtained under natural rainfall environments. The artificial rainfall simulation test must first consider the characteristics of rainfall. The most important thing is to solve the problem of rainfall control. The control of rainfall is the most important and direct characteristic in the rainfall simulation test.

[0003] The main characteristics of rainfall include rainfall intensity, uniformity of rainfall distribution, raindrop diameter and raindrop terminal velocity. In the field of soil and water conservation research, it has been recognized at home and abroad that the rainfall characteristics of artificial rainfall simulation devices are key factors affecting the accuracy of test results, and a number of artificial rainfall simulation devices with different performances have been developed one after another. According to the way raindrops are formed, artificial rainfall simulation devices can be divided into hanging wire type, needle type, pipe network type and sprinkler type. Among them, hanging wire type and needle type rainfall simulators can simulate small intensity rainfall, and the uniformity of rainfall distribution is good, but they have defects such as small control area, large and single raindrop diameter, and large difference between raindrop terminal velocity and natural rainfall, so the current application research is gradually reduced; pipe network type and sprinkler type rainfall simulators are closer to natural rainfall in raindrop diameter and raindrop terminal velocity, and are currently widely used in soil erosion test research.

[0004] For example, the SX2002 pipe network rainfall simulation device developed by Xu Xiangzhou et al. has a rainfall height of 3.5m, a rainfall area of ​​3.5m×2.5m, a rainfall intensity range of 1.0-4.0mm / min, a rainfall uniformity of more than 80%, and a raindrop size of 0-3mm; the needle-tube artificial rainfall device developed by Sun Kai et al. has a rainfall height of 1.6m, a rainfall area of ​​196250mm2, a rainfall intensity range of 0-15mm / h, a rainfall uniformity of more than 90%, and a raindrop size of 0-10mm; the suspended wire rainfall simulator developed by Bowyer-Bower uses a 0. 7mm, 2-3mm outer diameter, 15mm long polyethylene tube, the raindrop median diameter is 2-3mm; the rotary down-spray rainfall device developed by Huo Yunmei et al., the nozzle-type rainfall simulation device developed by Su Yina et al., and the rocker-arm up-spray rainfall simulation device developed by Zhang Jingling et al. The rainfall characteristics of various types of rainfall simulation devices are not the same. Among them, the needle-tube rainfall device has a limited control range of rainfall intensity; the hanging-wire rainfall device is not widely used in China; the nozzle-type rainfall device is mainly used outdoors, and the side-spraying device is greatly affected by the wind due to the large diameter of the raindrops. The destructive force of the down-spraying raindrops is difficult to calculate, and the rainfall uniformity of the up-spraying device is not stable enough. In addition, the existing rainfall simulation device development still has problems such as difficulty in self-circulation of rainwater, long test cycle, complex equipment installation and commissioning, and inconvenient operation of the sample rain shower platform. In terms of the calibration of the rainfall characteristics of the device, domestic and foreign research has been conducted on rainfall intensity, rainfall uniformity, raindrop diameter, raindrop terminal landing speed and rainfall kinetic energy. For example, Wu Guangyan et al. verified that the raindrop diameter characteristics conform to the Best distribution function through the study of natural rainfall raindrop characteristics; American scholar Ross et al.'s study on natural rainfall raindrops showed that the distribution of natural rainfall drop size fluctuates between 0-6mm. However, due to the different mechanisms of generating rainfall, different artificial rainfall simulation devices also need to carry out targeted rainfall characteristics experimental research.

[0005] As one of the important characteristics of natural rainfall, rainfall amount and rainfall intensity are the single indicators of many artificial rainfall simulation experiments and the most basic type of simulated rainfall. Simulated rainfall is to simulate natural rainfall, so in some studies, the choice of rainfall intensity is based on the existing natural rainfall data. For example, when Xu Ligang et al. studied the effects of different rainfall intensities on the vertical migration process and leaching loss of nutrients, the choice of rainfall intensity in their experiment was based on the probability frequency distribution analysis of the short-term rainfall intensity in the Fuxian Lake area over the years. Based on this, four different intensities representing the common short-term rainfall in the local area were determined as the experimental rainfall intensities.

[0006] A summary of published literature shows that the rainfall intensity of artificial simulated rainfall in my country depends more on the simulated rainfall device used. The rainfall intensity of the simulated rainfall device is mainly regulated by adjusting the flow rate and controlling the pressure. In their study on the effects of different rainfall intensities on farmland soil erosion, Sun Feida et al. showed that the rainfall intensity they adopted was to control the pressure of the rainmaker at 60KPa and the swing speed of the rainmaker to adjust the rainfall, and the average rainfall intensity was calculated after 30 minutes of observation. Zhang Guanghui et al. believe that according to the way rainfall is formed, artificial simulated rainfall machines can be divided into nozzle type and needle tube type. Generally, the rainfall intensity of a rainfall device with a sprinkler as a raindrop generator ranges from 30 to 150 mm / h. Researchers generally select a rainfall intensity within the rainfall intensity range that the rainfall device can provide as the rainfall intensity parameter for simulated rainfall.

[0007] Existing technologies ignore other important rainfall characteristics when emphasizing some rainfall characteristics, or there are some differences between the rainfall characteristics considered and the corresponding natural rainfall characteristics, which will lead to certain deviations in the understanding and mastery of the actual hydrological process and erosion mechanism. Due to the lack of understanding of natural rainfall characteristics, most geotechnical workers pay little attention to the accuracy of artificial rainfall simulation devices. Most of the self-designed rainfall devices only focus on the calibration relationship between rainfall intensity and water pressure, ignoring the importance of other indicators in rainfall parameters. Although some experiments have taken into account the impact of rainfall characteristics on slope water infiltration and slope erosion, due to the lack of consideration in the selection of raindrop generators, reliable artificial rainfall simulation parameters cannot be obtained. In addition, although there are mature artificial rainfall simulation devices, they generally have problems such as complex operation, high price, large size and poor mobility.

[0008] In the field of geotechnical engineering, rainfall is one of the main factors that induce landslides. A series of targeted field tests and physical model tests have been carried out at home and abroad to study the instability mechanism caused by rainfall factors. However, due to the lack of understanding of the characteristics of natural rainfall, most geotechnical workers pay little attention to the accuracy of artificial rainfall simulation devices. Most of the self-designed rainfall devices only focus on the calibration relationship between rainfall intensity and water pressure, ignoring the importance of other indicators in rainfall parameters. Although some experiments have taken into account the impact of rainfall characteristics on slope water infiltration and slope erosion, due to the lack of consideration in the selection of raindrop generators, including the single and rigid control method of rainfall, reliable artificial rainfall simulation parameters cannot be obtained. In addition, although there are mature artificial rainfall simulation devices, they generally have problems such as complex operation, high price, large size and poor mobility.

[0009] In view of this, this application aims at the problems existing in the current artificial rainfall simulation devices, refers to the experience of artificial rainfall simulation device design at home and abroad, and designs a rainfall control device for circulatory and movable rainfall test, and conducts rainfall characteristic calibration test on the device to verify the reliability of the device. Calibration tests on rainfall characteristics such as rainfall intensity, rainfall uniformity, raindrop diameter, raindrop terminal landing speed and rainfall kinetic energy under different rainfall intensities were also carried out on the device to provide guarantees for carrying out large-scale rainfall model tests and obtaining experimental data in a short period of time. The entire device uses a downward spray nozzle as a raindrop generator, and controls the rainfall by controlling the pressure of the water supply pipeline, opening and closing different types of nozzles, moving the canopy position and adjusting the angle of the permeable board, so as to realize artificial simulation rainfall processes with different rainfall intensities and durations. Summary of the invention

[0010] This application aims to solve the problems existing in current artificial rainfall simulation devices and designs a circulatory and movable rainfall control device for rainfall test based on the experience of artificial rainfall simulation device design at home and abroad. The specific technical solution is as follows:

[0011] The utility model discloses a rainfall controller for rainfall simulation test, which is composed of four parts: a water supply system, a sprinkler system, a rainfall control system and a rainwater return system.

[0012] The function of the water supply system is to provide water source and water pressure for the entire device, and it is mainly composed of a U-shaped water reservoir, a water pipe, a variable frequency self-priming pump, a flow meter, a check valve, a flexible joint and a main water supply pipeline;

[0013] Furthermore, four pulleys are installed at the bottom of the U-shaped water reservoir, and a variable frequency self-priming pump is connected to the end of the U-shaped water reservoir, and then connected to the main water supply pipe after passing through a flow meter, a check valve, and a flexible joint in sequence. The water supply system and the spraying system can be separated by rotating the flexible joint.

[0014] The sprinkler system is used to control and generate simulated rainfall, and is composed of a movable bracket, a branch pipe, a valve, a top water pipe and a sprinkler head;

[0015] Furthermore, the branch pipes include several ones, which are connected to the main water supply pipe through two-way joints. The branch pipes are connected to the top water pipe with a bend joint. The top water pipe is connected to the nozzle through a tee. Valves are installed on the branch pipes and the top water pipes to control the opening and closing of different types of nozzles.

[0016] The rainfall control system is used to support the water pipeline and control the rainfall, and is mainly composed of a mobile canopy, a track, a rain curtain and an inclined permeable board;

[0017] Furthermore, the movable canopy is an aluminum alloy frame structure, the top crossbeam is used to place the top water pipe, and the bottom crossbeams on both sides of the frame are welded with pulleys and can move along the track;

[0018] Furthermore, the rain curtain is used to collect rainwater sprayed outside the model box and gather it at the top of the U-shaped water storage tank. Since the top of the U-shaped water storage tank is inclined inward, the water will flow into the return groove on the inner wall of the U-shaped water storage tank, and then gather in the sedimentation tank, and then flow into the water tank through the rainwater return system;

[0019] Furthermore, the inclined permeable board is rotatably connected to the U-shaped water storage tank by bolts, and rainfall is simulated by drilling holes on the permeable board. The rainfall is controlled by adjusting the slope of the inclined permeable board and the position of the movable canopy. Rainwater that does not pass through the inclined permeable board will flow along the slope and into the sedimentation tank through the gap at the bottom, thereby realizing water recycling.

[0020] The rainwater return system is composed of a return self-priming pump, a sedimentation tank, a filter screen, a return trough, and a return pipe;

[0021] Furthermore, in addition to collecting rainwater sprayed outside the model box through the curtain, the reflux system also collects rainwater that has not passed through the inclined permeable plate along the slope, through the gap between the inclined permeable plate and the U-shaped water reservoir, and then flows into the sedimentation tank. After being filtered by the filter, the water is pumped back into the U-shaped water reservoir by the reflux self-priming pump, thereby realizing the reflux recycling of water.

[0022] The artificial rainfall simulation device of the present application has a total height of 4.6m, a length of 8.0m, and a width of 6.0m, and can be moved in conjunction with a mobile canopy.

[0023] The entire device uses downward-spraying nozzles as raindrop generators. By controlling the pressure of the water supply pipeline, opening and closing different types of nozzles, and adjusting the position of the canopy and the inclination angle of the inclined permeable board, artificial simulated rainfall processes of different rainfall intensities and durations can be achieved.

[0024] The advantages and effects of this application are as follows:

[0025] (1) The rainfall controller disclosed in the present invention has a variable frequency self-priming pump. The water in the U-shaped water tank then passes through a flow meter, a check valve, and a flexible joint in sequence and is connected to the main water supply pipeline. The water supply system and the sprinkler system can be separated by rotating the flexible joint.

[0026] (2) The rainfall controller disclosed in the present invention is a mobile canopy with an aluminum alloy frame structure. The top crossbeam is used to place the top water pipe. The bottom crossbeams on both sides of the frame are welded with pulleys and can move along the track. Three different specifications of downspout nozzles are combined to control the rainfall by controlling the pressure of the water pipeline.

[0027] (3) The rainfall controller disclosed in the present invention has an inclined permeable plate whose bottom end is fixed to the inner wall of a U-shaped pool by bolts. A gap is left between the fixed position and the wide side of the U-shaped pool so that rainwater that does not pass through the permeable holes can flow into the sedimentation tank below the gap along the slope. In addition, a hydraulic height adjustment device is used at the top of the permeable plate to adjust the angle of the inclined permeable plate. The holes on the permeable plate are 8×6 holes of different sizes, and the diameter is larger as it is closer to the top. The rainfall is controlled by adjusting the slope of the sloped permeable plate and the position of the mobile canopy on the track. The closer the canopy is to the holes of the permeable plate, the greater the rainfall that passes through the holes.

[0028] (4) The rainwater circulation system of the rainfall controller disclosed in the present invention has curtains on three sides of the mobile canopy, and a circle of return grooves on the inner wall of the U-shaped water tank to collect rainwater sprayed outside the model box and blocked by the curtains. The rainwater flows to the top of the U-shaped water tank through the curtains. Since the top of the U-shaped water tank is inclined inward, the rainwater will flow along the top of the water tank into the return groove on the inner side. In addition, the rainwater that has not passed through the permeable plate will flow along the slope through the gap between the permeable plate and the U-shaped water tank into the sedimentation tank. After being filtered by the filter, the water is pumped back into the U-shaped water tank by a self-priming pump, thereby realizing the reflux and recycling of water.

[0029] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application so that it can be implemented in accordance with the contents of the specification, and to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following is a detailed description of the preferred embodiments of the present application in conjunction with the accompanying drawings as follows.

[0030] Based on the detailed description of the specific embodiments of the present application in combination with the accompanying drawings below, those skilled in the art will become more aware of the above and other objects, advantages and features of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings without creative work. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual scale.

[0032] Figure 1 A stereoscopic diagram of a rainfall controller used in rainfall simulation tests

[0033] Figure 2 A front view of a rainfall controller used in rainfall simulation tests

[0034] Figure 3 Rear view of a rainfall controller used in rainfall simulation tests

[0035] Figure 4 A side view of a rainfall controller used in rainfall simulation tests

[0036] Figure 5 A partial connection diagram of a rainfall controller device used in rainfall simulation tests

[0037] Figure 6 A top view of a rainfall controller used in rainfall simulation tests

[0038] Figure numerals: 1-U-shaped water storage tank; 2-pulley; 3-variable frequency self-priming pump; 4-inclined permeable plate; 5-bolt; 6-sedimentation tank; 7-reflux self-priming pump; 8-reflux trough; 9-hydraulic device; 10-fixed beam; 11-slide rail; 12-mobile canopy; 13-sprinkler; 14-rain curtain. Specific embodiments

[0039] To make the purpose, technical scheme and advantages of the embodiment of the present application clearer, the technical scheme in the embodiment of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the present application. Obviously, the described embodiment is a part of the embodiment of the present application, rather than all of the embodiments. In the following description, specific details such as specific configuration and components are provided only to help fully understand the embodiments of the present application. Therefore, it should be clear to those skilled in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. In addition, for clarity and brevity, the description of known functions and structures is omitted in the embodiment.

[0040] It should be understood that the references to "one embodiment" or "this embodiment" throughout the specification mean that the specific features, structures, or characteristics associated with the embodiment are included in at least one embodiment of the present application. Therefore, the references to "one embodiment" or "this embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0041] In addition, the present application may repeat reference numerals and / or letters in different examples. This repetition is for the purpose of simplicity and clarity, and does not in itself indicate the relationship between the various embodiments and / or settings discussed.

[0042] The term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist at the same time. The term " / and" in this article describes another type of association object relationship, indicating that there can be two relationships. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the previous and next associated objects are in an "or" relationship.

[0043] The term "at least one" in this article is merely a description of the association relationship of associated objects, indicating that there may be three relationships. For example, at least one of A and B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0044] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusions.

[0045] Example 1

[0046] This embodiment introduces the basic structure of a rainfall controller used in rainfall simulation tests. Figure 1 , 2 , 3, 4, 5, Figure 1 A three-dimensional diagram of a rainfall controller used in rainfall simulation tests. Figure 2 A front view of a rainfall controller used in rainfall simulation tests. Figure 3 The rear view of a rainfall controller used in rainfall simulation tests. Figure 4 A side view of a rainfall controller used in rainfall simulation tests. Figure 5 This is a partial connection diagram of a rainfall controller device used for rainfall simulation test. Figure 6 A top view of a rainfall controller used in rainfall simulation tests.

[0047] A rainfall controller for rainfall simulation test, which consists of four parts: water supply system, sprinkler system, rainfall control system and rainwater return system;

[0048] The water supply system is arranged on the periphery of the lower half of the entire device;

[0049] The rainfall control system is arranged above the water supply system, and part of it is arranged in the middle U-shaped part of the water supply system;

[0050] The spray system is arranged on the rainfall control system and is located at the top of the entire device;

[0051] The rainwater return system is realized by the cooperation of the rainwater control system and some components of the water supply system.

[0052] The function of the water supply system is to provide water source and water pressure for the entire device, and is mainly composed of a U-shaped water reservoir 1, a water delivery pipe, a variable frequency self-priming pump 3, a flow meter, a check valve, a flexible joint and a main water supply pipeline;

[0053] Preferably, four pulleys 2 are installed at the bottom of the U-shaped water reservoir 1, and the variable frequency self-priming pump 3 is connected to the end of the U-shaped water reservoir 1, and then connected to the main water supply pipe after passing through a flow meter, a check valve, and a flexible joint in sequence. The water supply system and the spray system can be separated by rotating the flexible joint.

[0054] The spray system is used to control and generate simulated rainfall, and is composed of a movable bracket, a branch pipe, a valve, a top water pipe and a sprinkler 13;

[0055] Preferably, the branch pipes include several ones, which are connected to the main water supply pipe through two-way joints. The branch pipes are connected to the top water pipe with a bend joint, and the top water pipe is connected to the nozzle 13 through a tee. Valves are installed on the branch pipes and the top water pipe to control the opening and closing of different types of nozzles 13.

[0056] The rainfall control system is used to support the water pipeline and control the rainfall, and is mainly composed of a mobile canopy 12, a track, a rain curtain 14 and an inclined permeable board 4;

[0057] Preferably, the movable canopy 12 is an aluminum alloy frame structure, the top crossbeam is used to place the top water pipe, and the bottom crossbeams on both sides of the frame are welded with pulleys 2, which can move along the track;

[0058] Preferably, the rain curtain 14 is used to collect rainwater sprayed outside the model box and gather it at the top of the U-shaped water tank. Since the top of the U-shaped water tank 1 is inclined inward, the water will flow into the reflux groove 8 on the inner wall of the U-shaped water tank 1, and then gather into the sedimentation tank 6, and then flow into the water tank through the rainwater return system;

[0059] Preferably, the inclined water-permeable plate 4 is rotatably connected to the U-shaped water storage tank 1 by bolts 5, and rainfall is simulated by drilling holes on the inclined water-permeable plate 4, and the rainfall is controlled by adjusting the slope of the inclined water-permeable plate 4 and the position of the movable canopy 12; rainwater that does not pass through the inclined water-permeable plate 4 will flow along the slope and into the sedimentation tank 6 through the gap at the bottom, so as to realize water recycling.

[0060] The rainwater return system is composed of a return self-priming pump 7, a sedimentation tank 6, a filter screen, a return trough 8, and a return pipe;

[0061] In addition to collecting rainwater sprayed outside the model box through the curtain, the reflux system also collects rainwater that has not passed through the inclined permeable plate 4 along the slope, through the gap between the inclined permeable plate 4 and the U-shaped water storage tank 1 into the sedimentation tank 6, and after being filtered by the filter screen, the reflux self-priming pump 7 pumps the water back into the U-shaped water storage tank 1 to achieve the reflux recycling of water.

[0062] The artificial rainfall simulation device of the present application has a total height of 4.6 m, a length of 8.0 m, and a width of 6.0 m, and can be moved in conjunction with the mobile canopy 12 .

[0063] The whole device adopts downward spraying nozzle 13 as raindrop generator, and can realize artificial simulated rainfall process of different rainfall intensities and durations by controlling the pressure of water pipeline, opening and closing different types of nozzles 13, adjusting the position of canopy and the inclination angle of inclined water-permeable board 4.

[0064] The artificial simulated rainfall device designed in this paper has a total height of 4.6m, a length of 8.0m, and a width of 6.0m, and can be moved with the mobile canopy 3. The entire device uses a downward spray nozzle as a raindrop generator, and can realize artificial simulated rainfall processes of different rainfall intensities and durations by controlling the pressure of the water pipeline, opening and closing different types of nozzles, and adjusting the position of the canopy and the inclination angle of the inclined permeable board 4.

[0065] Example 2

[0066] This embodiment supplements the structural connection relationship of the rainfall controller used for rainfall simulation test on the basis of the above embodiment.

[0067] The bottom of the U-shaped water storage tank 1 is connected to four pulleys 2 for movement, and one end of the pulleys is connected to a variable frequency self-priming pump 3. The water storage tank 1 and the inclined permeable plate 4 are connected to the inner wall of the water storage tank 1 by two bolts 5. A sedimentation tank 6 and a reflux self-priming pump 7 are installed on the inner side of the U-shaped water storage tank 1, and an inclined reflux trough 8 is installed on the inner wall. The tail end of the reflux trough 8 is connected to the sedimentation tank 6 to collect rainwater collected on the top of the water storage tank. The bottom end of the inclined permeable plate 4 is connected to the inner wall of the U-shaped water storage tank by two bolts 5, and the connection position leaves a certain distance from the short side of the water storage tank. The top of the permeable plate 4 is connected to the fixed crossbeam 10 of the water storage tank through a hydraulic device 9 with adjustable height. The top of the U-shaped water storage tank 1 is made to be inclined toward the center, and a slide rail 11 is installed on the top to facilitate the movable canopy 12 to adjust the position. Nine nozzles 13 are arranged on the canopy 12, and rain-proof curtains 14 are arranged on three sides of the movable canopy 12. The external sprayed rainwater blocked by the curtain 14 will be gathered by the curtain to the top of the U-shaped water storage tank, and flow into the reflux groove 8 of the inner wall along the slope of the top of the water tank, and then flow into the sedimentation tank 6. The water in the sedimentation tank 6 passes through the filter screen and the reflux self-priming pump 7 and then returns to the U-shaped water storage tank 1.

[0068] The main function of the water supply system is to use a water pump to deliver the water in the water tank to the nozzle at a certain pressure through the water supply pipe. The water supply system designed this time is mainly composed of a water tank, a water pipe, a variable frequency self-priming pump, a flow meter, a check valve, a flexible joint and a main water supply pipe.

[0069] Example 3

[0070] This embodiment introduces the specific equipment and parameters used in each system of a rainfall controller for rainfall simulation test based on the above embodiments.

[0071] The water pump in the water supply system of the artificial rainfall simulation device designed in this application uses a variable frequency constant pressure single-phase self-priming booster pump produced by Jiangsu Wilo Pump Technology Co., Ltd. The specific parameters are: working voltage 220V, rated power 1.5kW, maximum head 65m, maximum flow 8m 2 / h, rated head 50m, rated flow 5m 3 / h, maximum suction range 9-15m, adjustable pressure 0-0.65bar. This pump is an intelligent variable frequency constant pressure water pump. Its built-in pressure sensor can monitor the outlet pipe pressure in real time and stabilize the outlet pipe pressure at the required pressure by adjusting the motor speed. When adjusting the rainfall intensity, you only need to adjust the button on the control panel to achieve pressure control of the entire rainfall device. Compared with adjusting the pressure by replacing the reducer and reading the water pressure gauge, this pump not only has a wide adjustable pressure range, but also controls the entire artificial simulated rainfall device more quickly and efficiently.

[0072] The water pipe and main water supply pipe use PPR pipe with inner diameter of 25mm, and the top 8 water pipes connected to the sprinkler are PPR pipe with inner diameter of 20mm; the height of the vertical water pipe is 4.6m, and when the water reaches the top branch pipes, the water pressure will lose about 0.46bar, and the bottom horizontal water pipe is 5m, and the water pressure loss caused by friction in the pipe is negligible. Therefore, in order to make each sprinkler reach normal working state, the minimum pressure of the water pump outlet should be set to 0.9bar.

[0073] The nozzle is located 4.6m above the water pump. The nozzle is the core part of the artificial rainfall simulation device and determines the reliability of the device. The raindrop generator of the artificial rainfall simulation device developed in this experiment is a Fulljet rotary down-spray nozzle produced by an American company. The raindrop diameter and raindrop energy of this nozzle are highly similar to natural rainfall, and it has been configured on some more advanced artificial rainfall simulation devices in China. The nozzles are divided into three specifications: 1# (nozzle diameter: 3.2mm), 2# (nozzle diameter: 1.5mm), and 3# wide-angle (nozzle diameter: 2.0mm). Reasonable nozzle superposition arrangement can effectively reduce the unevenness of rainfall intensity within the rainfall coverage range. The rainfall coverage range of the model test is 5m×3m. The three nozzles are arranged according to the minimum rainfall coverage diameter. The design uses 9 1# nozzles, 9 2# nozzles, and 2 3# wide-angle nozzles. Through the control valves on each pipeline, different types of nozzles can be opened separately, and all can achieve comprehensive rainfall in the model box.

[0074] The U-shaped pool is made of plexiglass and is factory customized. Users can see the overflow of the water in the pool to conduct operation inspections. The three tops are inclined inwards, and the rainwater blocked by the curtain will flow along the top of the water tank into the reflux groove on the inner wall and then into the sedimentation tank.

[0075] Example 4

[0076] This embodiment introduces the specific assembly steps of a rainfall controller used in rainfall simulation test based on the above embodiments.

[0077] One end of the U-shaped water storage tank is connected to a variable frequency water pump. There are two slide rails on the inclined top of the water storage tank. The mobile canopy can move on the rails. Rain curtains are arranged on three sides of the canopy to block the rainwater sprayed from the nozzles. Different types of nozzles are installed on the top of the canopy. There are 6×8 holes on the inclined permeable plate, which is connected to the inner wall of the U-shaped water storage tank by bolts. There is a certain gap between the connection point and the wide side of the U-shaped water storage tank, which is convenient for rainwater to flow into the sedimentation tank on the inner wall of the water storage tank. The other end of the inclined permeable plate can be adjusted in height by a hydraulic device. A part of the rainwater that does not pass through the inclined permeable plate flows into the sedimentation tank, and the other part is blocked by the curtain and flows through the inclined top of the U-shaped water storage tank into the reflux tank on the inner wall. After being filtered by the filter, the water is pumped back into the U-shaped water storage tank by the self-priming pump.

[0078] Example 4

[0079] This embodiment further illustrates the water supply problem of a rainfall controller used in a rainfall simulation test based on the above embodiments.

[0080] The water pump is the core component of the water supply system, providing the pressure source for the entire artificial rainfall simulation device. Its selection mainly considers three factors: flow rate, head and adjustable pressure. The water pump in the water supply system of the artificial rainfall simulation device designed in this paper uses the variable frequency constant pressure single-phase self-priming booster pump produced by Jiangsu Wilo Pump Industry Technology Co., Ltd. The specific parameters are: working voltage 220V, rated power 1.5kW, maximum head 65m, maximum flow 8m 2 / h, rated head 50m, rated flow 5m 3 / h, maximum suction range 9~15m, adjustable pressure 0~0.65bar. The pump is an intelligent variable frequency constant pressure water pump. Its built-in pressure sensor can monitor the outlet pipe pressure in real time, and stabilize the outlet pipe pressure at the required pressure by adjusting the motor speed. When adjusting the rainfall intensity, you only need to adjust the button on the control panel to achieve pressure control of the entire rainfall device. Compared with adjusting the pressure by replacing the reducer and reading the water pressure gauge, this pump not only has a wide adjustable pressure range, but also controls the entire artificial simulated rainfall device more quickly and efficiently. In addition, compared with the power system of the current artificial simulated rainfall device with CNC function, this pump is simple to operate and low in price, which can greatly reduce the production cost.

[0081] In artificial rainfall simulation, in addition to considering the portability and operability of the instruments used in the test, the supply of water and electricity is a decisive issue in whether the test can be carried out. The installation height of the artificial rainfall simulation device is related to the characteristics of the raindrops. As mentioned above, the higher the height, the closer the raindrops are to natural rainfall. However, for the sake of safety and operational feasibility, especially under field test conditions, the control of water supply pressure in artificial rainfall simulation is another important issue in the test. Due to the selection of water pipeline materials, the repeatability of the test under the same pressure is poor, so it is best to choose materials that are not easy to deform in the test. Previous devices and equipment often ignore the characteristics of the water pipeline itself, thereby affecting the water supply pressure and causing inaccurate experimental results.

[0082] Example 5

[0083] This embodiment further illustrates the selection and arrangement of nozzles of a rainfall controller for a rainfall simulation test based on the above embodiments.

[0084] This device uses a sprinkler-type rainfall device, which has good uniformity of rainfall distribution and is closer to natural rainfall in terms of raindrop diameter and raindrop terminal velocity. Sprinkler-type rainfall devices are mainly used outdoors, and side-spraying devices are greatly affected by wind due to their large raindrop diameter. The curtain of this device also reduces the impact of wind on the sprinkler to a certain extent. Reasonable sprinkler superposition arrangement can effectively reduce the unevenness of rainfall intensity within the rainfall coverage range. The rainfall coverage range of the model test is 5m×3m. The three sprinklers are arranged according to the minimum rainfall coverage diameter. The design uses 9 1# sprinklers, 9 2# sprinklers, and 2 3# sprinklers. Different types of sprinklers can be opened separately through the control valves on each pipeline. In addition, the three sprinklers can be rotated at an angle to achieve comprehensive rainfall in the model box. The existing rainfall controller for rainfall simulation has not fully considered the various combinations of different types, including the angle, which is basically fixed.

[0085] Example 6

[0086] This embodiment further illustrates the rainfall control problem of a rainfall controller used in a rainfall simulation test based on the above embodiments.

[0087] The rainfall controller designed in this application for rainfall simulation test is a circulatory and movable artificial rainfall simulation device, which is easy to operate, easy to disassemble and has low manufacturing cost. The device is combined with 3 different specifications of downspout nozzles. The rainfall can be controlled by controlling the pressure of the water pipeline, opening and closing different types of nozzles, adjusting the position of the canopy and the inclination angle of the permeable board, and realizing artificial rainfall simulation processes of different rainfall intensities and durations.

[0088] Example 7

[0089] This embodiment further illustrates the problem of rainwater circulation of a rainfall controller used in a rainfall simulation test based on the above embodiments.

[0090] The rainwater return system consists of a self-priming pump, a sedimentation tank, a filter, a return trough, and a return pipe. In addition to collecting rainwater sprayed outside the model box through a curtain, the return system also collects rainwater that has not passed through the permeable plate along the slope, through the gap between the permeable plate and the U-shaped water tank, and then flows into the sedimentation tank. After being filtered by the filter, the water is pumped back into the U-shaped water tank by a self-priming pump, thereby realizing the return and recycling of water.

[0091] The above description is only the preferred embodiment of the present invention, which does not limit the protection scope of the present invention. For those skilled in the art, the present invention can be modified and varied in various ways. Within the spirit and principle of the present invention, any change, modification, replacement, integration and parameter change of these embodiments by conventional substitution or capable of achieving the same function without departing from the principle and spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. A rainfall controller for rainfall simulation test, characterized in that: It consists of four parts: water supply system, sprinkler system, rainfall control system and rainwater return system; The water supply system is arranged on the periphery of the lower half of the entire device; The rainfall control system is arranged above the water supply system, and part of it is arranged in the middle U-shaped part of the water supply system; The spray system is arranged on the rainfall control system and is located at the top of the entire device; The rainwater return system is realized by the cooperation of the rainwater control system and some components of the water supply system.

2. A rainfall controller for rainfall simulation test as claimed in claim 1, characterized in that: The function of the water supply system is to provide water source and water pressure for the entire device, and is mainly composed of a U-shaped water reservoir (1), a water pipe, a variable frequency self-priming pump (3), a flow meter, a check valve, a flexible joint and a main water supply pipeline; Four pulleys (2) are installed at the bottom of the U-shaped water reservoir (1), and a variable frequency self-priming pump (3) is connected to the end of the U-shaped water reservoir (1), and then connected to the main water supply pipeline after passing through a flow meter, a check valve, and a flexible joint in sequence. The water supply system and the spray system can be separated by rotating the flexible joint.

3. A rainfall controller for rainfall simulation test as claimed in claim 1, characterized in that: The spray system is used to control and generate simulated rainfall, and is composed of a movable bracket, a branch pipe, a valve, a top water pipe and a spray head (13); The branch pipes include a plurality of branch pipes connected to the main water supply pipe via two-way joints. The branch pipes are connected to the top water pipe via an elbow joint. The top water pipe is connected to the nozzle (13) via a tee. Valves are installed on the branch pipes and the top water pipe to control the opening and closing of different types of nozzles (13).

4. A rainfall controller for rainfall simulation test as claimed in claim 1, characterized in that: The rainfall control system is used to support the water pipeline and control the rainfall, and is mainly composed of a movable canopy (12), a track, a rain curtain (14) and an inclined water-permeable board (4); The movable canopy (12) is an aluminum alloy frame structure, the top crossbeam is used to place the top water pipe, and the bottom crossbeams on both sides of the frame are welded with pulleys (2) so that it can move along the track; The rain curtain (14) is used to collect rainwater sprayed outside the model box and gather it at the top of the U-shaped water tank. Since the top of the U-shaped water tank (1) is inclined inward, the water will flow into the return groove (8) on the inner wall of the U-shaped water tank (1), and then gather in the sedimentation tank (6), and then flow into the water tank through the rainwater return system; The inclined water-permeable plate (4) is rotatably connected to the U-shaped water storage tank (1) via bolts (5). Rainfall is simulated by drilling holes on the inclined water-permeable plate (4). The amount of rainfall is controlled by adjusting the slope of the inclined water-permeable plate (4) and the position of the movable canopy (12). Rainwater that does not pass through the inclined water-permeable plate (4) flows along the slope through the gap at the bottom into the sedimentation tank (6), thereby realizing water recycling.

5. A rainfall controller for rainfall simulation test as claimed in claim 1, characterized in that: The rainwater return system is composed of a return self-priming pump (7), a sedimentation tank (6), a filter screen, a return trough (8), and a return pipe; In addition to collecting rainwater sprayed outside the model box through the curtain, the return system also collects rainwater that has not passed through the inclined water-permeable plate (4) along the slope through the gap between the inclined water-permeable plate (4) and the U-shaped water storage tank (1) into the sedimentation tank (6). After being filtered by the filter screen, the water is pumped back into the U-shaped water storage tank (1) by the return self-priming pump (7), thereby realizing the return and recycling of water.

6. A rainfall controller for rainfall simulation test as claimed in claim 1, characterized in that: The artificial rainfall simulation device of the present application has a total height of 4.6 m, a length of 8.0 m, and a width of 6.0 m, and can be moved in conjunction with a mobile canopy (12).

7. A rainfall controller for rainfall simulation test as claimed in claim 1, characterized in that: The entire device uses a downward spray nozzle (13) as a raindrop generator, and can control the pressure of a water pipeline, open and close different types of nozzles (13), and adjust the position of the canopy and the inclination angle of the inclined water-permeable board (4) to achieve an artificial simulated rainfall process with different rainfall intensities and durations.

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