A circulating water supply device for centrifugal model test under high g value

Abstract

The invention discloses a circulating water supply device for centrifugal model test under high g value, comprising a water circulation pump group, a servo control system and a water delivery pipeline; the water circulation pump group is composed of six groups of double-acting reciprocating water pumps, and the six groups of double-acting reciprocating water pumps are symmetrically arranged on both sides of the model box of the centrifugal model test; the model box is divided into two layers, the upper layer is the model area for the test, and the lower layer is a water storage tank for storing test water; each group of double-acting reciprocating water pumps is composed of a bidirectional hydraulic servo actuator and two water cylinders connected to both ends of the servo actuator; the servo actuator is used to control the operation of the double-acting reciprocating water pump; the servo control system feeds back real-time data of the water supply process, and controls the servo actuator to complete the water supply. The device of the invention has the advantages of large water supply flow, can work in a high-g value hypergravity environment, novel design, and less impact on the surrounding environment.

Description

Technical Field

[0001] The invention relates to the technical field of geotechnical centrifuges, and in particular to a circulating water supply device used for centrifugal model tests under high g values. Background Art

[0002] The technology of continuous water supply and control of large flow rate of centrifuge under high centrifugal force is a technical difficulty in centrifugal model test. The following problems must be solved to realize the centrifugal model test under hydraulic action: First, a suitable water flow control system must be provided in the centrifuge system, and the system should be able to continuously provide sufficient water during the test; second, when the water flows into the model box, the impact force of the high-speed water flow cannot damage the bottom plate of the buffer tank, and cannot have too high kinetic energy to avoid destroying the model; third, the test water flow does not affect the normal operation of the electronic equipment inside the model box; fourth, in the high gravity field, all components can work normally. Nanjing Institute of Water Science and Technology adopted a water supply system with the idea of ​​rotating water ring and developed a large flow model water flow control system. The test water of this system needs to be discharged directly into the centrifuge room. The atomized water vapor formed by the high-speed rotation of the water flow will corrode the main machine and affect the service life of the main machine. Beijing University of Technology invented a water circulation device that can be used in a centrifuge. The experimental device can provide a closed water circulation space to avoid the influence of water mist caused by water discharge on the test and damage to the centrifuge equipment. However, since the operation of the water pump is inhibited in the centrifuge, in order to provide a large flow rate for the model under high acceleration, the water pump needs a lot of power. At this time, the volume of the water pump will increase, thereby increasing the size of the model box and the weight of the entire device, which is not conducive to the experiment. Summary of the invention

[0003] In view of the shortcomings of the existing centrifugal model test water supply device, the present invention provides a circulating water supply device for centrifugal model test under high g value.

[0004] The object of the present invention is achieved through the following technical solutions: a circulating water supply device for centrifugal model test under high g value, comprising a water circulating pump group, a servo control system and a water delivery pipeline; the water circulating pump group is composed of six groups of double-acting reciprocating water pumps, and the six groups of double-acting reciprocating water pumps are symmetrically arranged on both sides of the model box of the centrifugal model test; the model box is divided into two layers, the upper layer is the model area for the test, and the lower layer is a water tank for storing test water; each group of double-acting reciprocating water pumps is composed of a bidirectional hydraulic servo actuator and a The servo actuator is composed of two water cylinders at both ends; the water inlet of each set of double-acting reciprocating water pumps is connected to the water suction check valve through a water supply pipeline, the water suction check valve is connected to the water storage tank at the lower layer of the model box through the water supply pipeline, the water outlet of each set of double-acting reciprocating water pumps is connected to the drainage check valve through a water supply pipeline, and the drainage check valve is connected to the model area at the upper layer of the model box through the water supply pipeline; the servo actuator is used to control the operation of the double-acting reciprocating water pump; the servo control system feeds back real-time data of the water supply process and controls the servo actuator to complete the water supply.

[0005] Furthermore, one of the six groups of double-acting reciprocating water pumps is on standby, and the other five groups operate sinusoidally with a certain phase difference under the control of the servo actuator, that is, one operation cycle is divided into 360°. Since the structure of each pump is a double-acting two-chamber symmetrical reciprocating pump, each pump will output a half-sine wave flow rate within the half cycle of piston extension or contraction. By controlling the starting point of the operation cycle to make it relatively delayed by 36°, the flow of each pump in the half cycle is complemented, forming a final output with a smaller total flow pulsation.

[0006] Furthermore, the water delivery pipeline is a stainless steel seamless steel pipe, which is fixed on the model box through a water pipe bracket.

[0007] Furthermore, the six groups of double-acting reciprocating water pumps are arranged in parallel with each other.

[0008] Furthermore, the water cylinder body of the double-acting reciprocating water pump is composed of an aluminum alloy and a ceramic-coated cylinder liner.

[0009] Furthermore, the actuator cylinder of the servo actuator is made of ultra-high strength alloy steel with a yield strength of more than 1 GPa.

[0010] Furthermore, the hydraulic rods at both ends of the servo actuator are coaxially connected to the piston rod of the double-acting reciprocating water pump, and the piston is driven to reciprocate in the water cylinder through the piston rod.

[0011] Furthermore, two piston rods at both ends of the double-acting reciprocating water pump that cooperate with the water cylinder form a cantilever structure, and the cantilever structure is supported by a linear guide rail.

[0012] Furthermore, the servo control system includes a flow sensor and a displacement sensor. The flow sensor is installed on a water supply pipeline connected to the model area on the upper layer of the model box to measure the water flow entering the model area. The displacement sensor is used to measure the hydraulic rod position of the servo actuator to obtain the piston extension and contraction amount of the double-acting reciprocating water pump.

[0013] The method for using the circulating water supply device comprises the following steps:

[0014] Step A, arranging three sets of double-acting reciprocating water pumps on both sides of the model box, connecting the water inlet of the double-acting reciprocating water pump to the water storage tank at the lower layer of the model box through a water delivery pipeline, connecting the water outlet of the double-acting reciprocating water pump to the model area at the upper layer of the model box through a water delivery pipeline, and then fixing the water delivery pipeline and the model box together;

[0015] Step B, adding water to the water tank, testing the circulating water supply device after the water tank is filled with water, and disconnecting the power supply after the test is completed;

[0016] Step C, placing the installed circulating water supply device and the model box on the model installation workbench, and making a geotechnical centrifuge model in the model area on the upper layer of the model box;

[0017] Step D, the model box of the geotechnical centrifuge model is placed in the centrifuge basket and fixed, the power supply of the circulating water supply device is turned on, and the servo actuator is controlled by the servo control system to complete the water supply.

[0018] The beneficial effects of the present invention are as follows: the present invention provides a circulating water supply device for centrifugal model test under high g value, comprising a water circulating pump group, a servo control system and a water delivery pipeline; the water circulating pump group is composed of six groups of double-acting reciprocating water pumps, each group of double-acting reciprocating water pumps is composed of a bidirectional hydraulic servo actuator and two water cylinders connected at both ends of the servo actuator, which can increase the water supply flow; one group of the six groups of double-acting reciprocating water pumps is standby, and the other five groups operate sinusoidally according to a certain phase difference under the control of the servo actuator, that is, one operation cycle is divided into 360 degrees, and because each group of double-acting reciprocating water pumps is used as a spare, the other five groups operate sinusoidally according to a certain phase difference under the control of the servo actuator, that is, one operation cycle is divided into 360 degrees, and because each group of double-acting reciprocating water pumps is used as a spare, the other five groups operate sinusoidally according to a certain phase difference under the control of the servo actuator, that is, one operation cycle is divided into 360 degrees, and because each group of double-acting reciprocating water pumps is used as a spare, the other five groups of double-acting reciprocating water pumps are used as a spare, and ... The pump structure is a double-acting two-chamber symmetrical reciprocating pump. Each pump piston will output a semi-sine wave flow rate in the half cycle of extension or contraction. By controlling the starting point of the operation cycle, it is relatively delayed by 36°, so that the flow of each pump is complementary in the half cycle, forming a final output with a smaller total flow pulsation; the cantilever structure formed by the two piston rods at both ends of the double-acting reciprocating water pump is supported by a linear guide rail and can be placed under large deformation under high g values; the device of the present invention has the advantages of large water supply flow, can work in a high-g value ultra-gravity environment, novel design, and less impact on the surrounding environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is an assembly diagram of the overall structure of the circulating water supply device of the present invention;

[0020] Figure 2 It is a schematic diagram of the overall structure of the circulating water supply device of the present invention;

[0021] Figure 3 It is a front view of the overall structure of the circulating water supply device of the present invention;

[0022] Figure 4 It is a top view of the overall structure of the circulating water supply device of the present invention;

[0023] Figure 5 It is a side view of the overall structure of the circulating water supply device of the present invention;

[0024] Figure 6 It is a schematic diagram of the working principle of the double-acting reciprocating water pump of the present invention;

[0025] Figure 7 is a side view of a double-acting reciprocating water pump of the present invention;

[0026] Figure 8 is a top view of the double-acting reciprocating water pump of the present invention;

[0027] Fig. 9 yes Figure 8 AA section view;

[0028] In the figure, the model box 1, the water inlet pipe 2, the water suction pipe 3, the water circulation pump group 4, the servo actuator 5, the double-acting reciprocating water pump 6, the linear guide 7, the hydraulic rod 8, the piston rod 9, the water pipe bracket 10, the valve block 11, the water inlet 12, the water suction check valve 13, the drainage check valve 14, the A cavity water inlet 15, the A cavity drainage port 16, the B cavity water inlet 17, the B cavity drainage port 18, the actuator cylinder head 19, the actuator cylinder body 20, the actuator valve block 21, the water cylinder body 22, the water pump end cover 23, the water pump piston support ring 24, the water pump piston rod support ring 25, the piston rod connecting piece 26, and the actuator piston 27. DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0030] like Figure 1-5As shown, the present invention provides a circulating water supply device for centrifugal model test under high g value, including a water circulation pump group 4, a servo control system and a water supply pipeline; the water circulation pump group is composed of six groups of double-acting reciprocating water pumps 6, and the six groups of double-acting reciprocating water pumps 6 are symmetrically arranged on both sides of the model box 1 of the centrifugal model test; the model box 1 is divided into two layers, the upper layer is the model area for the test, and the lower layer is a water storage tank for storing test water; each group of double-acting reciprocating water pumps 6 is composed of a bidirectional hydraulic servo actuator 5 and two water cylinders connected to both ends of the servo actuator 5; the water inlet of each group of double-acting reciprocating water pumps 6 is connected to the water suction check valve 13 through the water supply pipeline, and the water suction check valve 13 is connected to the water suction check valve 13 through the water supply pipeline. The valve 13 is connected to the water storage tank at the lower layer of the model box 1 through the suction pipe 3, the water outlet of each group of double-acting reciprocating water pumps 6 is connected to the drainage check valve 14 through the water supply pipeline, and the drainage check valve 14 is connected to the model area at the upper layer of the model box 1 through the water supply pipeline; the water flows into the suction pipe 3 through the water inlet 12, enters the water inlet pipe 2 through the piston of the double-acting reciprocating water pump 6, and finally flows to the model area at the upper layer of the model box 1; the servo actuator 5 is a hydraulic cylinder, which performs reciprocating motion as designed under the action of the servo control system; the servo actuator 5 is used to control the operation of the double-acting reciprocating water pump 6; the servo control system feeds back real-time data of the water supply process, and controls the servo actuator 5 to complete the water supply.

[0031] One of the six groups of double-acting reciprocating water pumps 6 is in standby mode, and the other five groups operate sinusoidally with a certain phase difference under the control of the servo actuator 5, that is, one operation cycle is divided into 360°. Since the structure of each pump is a double-acting two-chamber symmetrical reciprocating pump, each pump piston will output a half-sine wave flow rate within the half cycle when it extends or contracts. By controlling the starting point of the operation cycle to make it lag behind by 36°, the flow rates of each pump in the half cycle are complemented, forming a final output with a smaller total flow pulsation.

[0032] The water delivery pipeline is a stainless steel seamless steel pipe, which is fixed on the model box 1 through a water pipe bracket 10, and the valve block 11 for suction and drainage is integrated with the water delivery pipeline.

[0033] The six groups of double-acting reciprocating water pumps 6 are arranged in parallel with each other; when the double-acting reciprocating water pumps 6 are in operation, the piston rods 9 at both ends will form a cantilever structure, and in order to prevent large deformation, the two sides are supported by linear guide rails 7 for movement.

[0034] The actuator cylinder 20 of the servo actuator 5 is made of ultra-high strength alloy steel with a yield strength of more than 1GPa. The hydraulic rods 8 at both ends of the servo actuator 5 are coaxially connected with the piston rod 9 of the double-acting reciprocating water pump 6. The piston rod 9 drives the piston to reciprocate in the water cylinder. The water cylinder drains water on one side of the piston movement and absorbs water on the other side. Figure 6It is a schematic diagram of the working principle of the double-acting reciprocating water pump of the present invention. When the double-acting reciprocating water pump is working, the piston moves up, the lower left sucks liquid, and the upper right discharges liquid. The piston moves down, the upper left sucks liquid, and the lower right discharges liquid. The piston reciprocates once, and there are two suction and discharge operations.

[0035] The structure of a double-acting reciprocating water pump is as follows Figure 7-9 As shown. The water cylinder connected at both ends of the servo actuator 5 includes a water cylinder body 22, a water pump end cover 23, a water pump piston support ring 24, and a water pump piston rod support ring 25. The water pump piston support ring 24 is used to support the water pump piston, and the water pump piston rod support ring 25 is used to support the piston rod 9. The water cylinder body 22 has an A-chamber water inlet 15, an A-chamber drain port 16, a B-chamber water inlet 17, and a B-chamber drain port 18. The water cylinder body 22 can be composed of a cylinder sleeve coated with aluminum alloy and ceramic. The servo actuator 5 includes an actuator cylinder head 19, an actuator cylinder body 20, an actuator valve block 21, and an actuator piston 27 that cooperates with the hydraulic rod 8. The hydraulic rod 8 and the piston rod 9 are connected by a piston rod connector 26.

[0036] The servo control system includes a flow sensor and a displacement sensor. The flow sensor is installed on the water delivery pipeline connected to the model area on the upper layer of the model box 1, and is used to measure the water flow entering the model area and provide feedback. The displacement sensor is used to measure the position of the hydraulic rod 8 of the servo actuator 5 and provide feedback to obtain the piston extension amount of the double-acting reciprocating water pump 6. The servo control system communicates with the remote controller, and controls the signal generator to generate the required control signal, which is output to the servo actuator 5 to complete the closed-loop control of the water flow.

[0037] The method for using the circulating water supply device for centrifugal model test under high g value of the present invention comprises the following steps:

[0038] Step A, three groups of double-acting reciprocating water pumps 6 are arranged on both sides of the model box 1, the water inlet of the double-acting reciprocating water pump 6 is connected to the water storage tank at the lower layer of the model box 1 through a water delivery pipeline, the water outlet of the double-acting reciprocating water pump 6 is connected to the model area at the upper layer of the model box 1 through a water delivery pipeline, and then the water delivery pipeline is fixed to the model box 1;

[0039] Step B, adding water to the water tank, testing the circulating water supply device after the water tank is filled with water, and disconnecting the power supply after the test is completed;

[0040] Step C, placing the installed circulating water supply device and the model box 1 on the model installation workbench, and making a geotechnical centrifuge model in the model area on the upper layer of the model box 1;

[0041] Step D: Hang the model box 1 of the geotechnical centrifuge model into the centrifuge basket and fix it, turn on the power of the circulating water supply device, and control the servo actuator 5 through the servo control system to complete the water supply.

[0042] Personnel in the technical field can easily make various changes and modifications based on the text description, drawings and claims provided by the present invention without departing from the concept and scope of the present invention defined by the claims. Any modification or equivalent change made to the above embodiments based on the technical concept and essence of the present invention shall fall within the scope of protection defined by the claims of the present invention.

Claims

1. A circulating water supply device for centrifugal model test under high g value, characterized in that: It comprises a water circulation pump group, a servo control system and a water supply pipeline; the water circulation pump group is composed of six groups of double-acting reciprocating water pumps, which are symmetrically arranged on both sides of the model box of the centrifugal model test; the model box is divided into two layers, the upper layer is the model area for the test, and the lower layer is the water storage tank for storing the test water; each group of double-acting reciprocating water pumps is composed of a bidirectional hydraulic servo actuator and two water cylinders connected to the two ends of the servo actuator; the water inlet of each group of double-acting reciprocating water pumps is connected to the water suction check valve through the water supply pipeline, the water suction check valve is connected to the water storage tank in the lower layer of the model box through the water supply pipeline, the water outlet of each group of double-acting reciprocating water pumps is connected to the drainage check valve through the water supply pipeline, and the drainage check valve is connected to the model area in the upper layer of the model box through the water supply pipeline; the servo actuator is used to control the operation of the double-acting reciprocating water pump; the servo control system feeds back the real-time data of the water supply process, and controls the servo actuator to complete the water supply; One of the six double-acting reciprocating water pumps is in standby mode, and the other five operate sinusoidally with a certain phase difference under the control of the servo actuator, that is, one operating cycle is divided into 360°. Since each pump is a double-acting two-chamber symmetrical reciprocating pump, each pump will output a half-sine wave flow rate in the half cycle when the piston extends or contracts. By controlling the starting point of the operating cycle to lag 36° relative to each other, the flow of each pump in the half cycle is complemented, forming a final output with a smaller total flow pulsation; The water delivery pipeline is a stainless steel seamless steel pipe, which is fixed on the model box through a water pipe bracket; The six groups of double-acting reciprocating water pumps are arranged in parallel with each other; The water cylinder body of the double-acting reciprocating water pump is composed of an aluminum alloy and a ceramic-coated cylinder sleeve; The actuator cylinder of the servo actuator is made of ultra-high strength alloy steel with a yield strength of more than 1GPa; The hydraulic rods at both ends of the servo actuator are coaxially connected to the piston rod of the double-acting reciprocating water pump, and the piston is driven to reciprocate in the water cylinder through the piston rod; The two piston rods at both ends of the double-acting reciprocating water pump cooperate with the water cylinder to form a cantilever structure, and the cantilever structure is supported by a linear guide rail; The servo control system includes a flow sensor and a displacement sensor. The flow sensor is installed on a water supply pipeline connected to the model area on the upper layer of the model box to measure the water flow entering the model area. The displacement sensor is used to measure the hydraulic rod position of the servo actuator to obtain the piston extension and contraction amount of the double-acting reciprocating water pump.

2. A method for using the circulating water supply device according to claim 1, characterized in that: The following steps are involved: Step A, arranging three sets of double-acting reciprocating water pumps on both sides of the model box, connecting the water inlet of the double-acting reciprocating water pump to the water storage tank at the lower layer of the model box through a water delivery pipeline, connecting the water outlet of the double-acting reciprocating water pump to the model area at the upper layer of the model box through a water delivery pipeline, and then fixing the water delivery pipeline and the model box together; Step B, adding water to the water tank, testing the circulating water supply device after the water tank is filled with water, and disconnecting the power supply after the test is completed; Step C, placing the installed circulating water supply device and the model box on the model installation workbench, and making a geotechnical centrifuge model in the model area on the upper layer of the model box; Step D, the model box of the geotechnical centrifuge model is hoisted into the centrifuge basket and fixed, the power supply of the circulating water supply device is turned on, and the servo actuator is controlled by the servo control system to complete the water supply.

Images