CN206961386U - A kind of reynolds test instrument - Google Patents

Abstract

The utility model relates to a Renault experimental instrument, which comprises a water temperature control system, an experimental rectification system, an experimental demonstration system and a water circulation system. The technical problem to be solved by the utility model is to provide a Reynolds number for the existing Reynolds experimental instrument completely relying on changing the flow velocity of the water flow in the circular tube to provide a The Reynolds experimental instrument that changes the Reynolds number by changing the water temperature reduces the influence of the water flow disturbance caused by the adjustment of the flow velocity on the experimental results.

Description

A Reynolds Test Apparatus

technical field

The utility model relates to a novel Renault experimental device, which belongs to the field of hydraulic experimental instruments.

Background technique

The Reynolds experiment has an important position in the history of hydraulics development. It is an important experiment for beginners in hydraulics to understand the two flow states of laminar flow and turbulent flow and their transition and transformation laws. Therefore, the Reynolds tester is a kind of instrument in hydraulics teaching Indispensable teaching experimental device.

When the pipe diameter is constant, as the flow velocity changes, different flow regimes can appear in the circular pipe. Generally, the flow state of the water flow can be judged by calculating the Reynolds number of the circular pipe. The Reynolds tester is a teaching device for demonstrating the motion state of water flow at different Reynolds numbers and the mutual transformation process between laminar flow and turbulent flow by changing the Reynolds number of water flow in a circular tube.

At present, the change of the Reynolds number in the Reynolds tester is mainly achieved by changing the flow velocity in the circular tube. The change of the flow velocity is often achieved by adjusting the flow rate. However, in actual operation, the water flow disturbance caused by the flow velocity adjustment will directly affect the experiment. The results and accuracy of the results and accuracy, especially the critical stage of water flow transition from laminar flow to turbulent flow or turbulent flow to laminar flow, the observed experimental rules are not obvious, the critical Reynolds number obtained by repeated experiments is not stable, and the deviation is large, for This is especially true for operators who are not familiar with the two flow states of water flow and their transformation relations, which may even affect the teaching effect of the experiment and students' cognition of Reynolds number.

Therefore, it is necessary to use a new experimental device to reduce the impact of flow changes in the critical stages of the experiment on the accuracy of the experiment and improve the teaching effect of the experiment.

Utility model content

The technical problem to be solved by the utility model is to provide a Reynolds number for the existing Reynolds experimental instrument to adjust the Reynolds number completely by changing the water flow velocity in the circular tube, and to provide a The Reynolds experimental instrument that changes the Reynolds number by changing the water temperature reduces the influence of the water flow disturbance caused by the adjustment of the flow velocity on the experimental results.

In order to solve the above-mentioned technical problems, the utility model proposes the following technical proposals: a Renault experimental instrument, which includes a water temperature control system, an experimental rectification system, an experimental demonstration system and a water circulation system;

The water temperature control system is composed of a hot water system module, a cold water system module and a water mixing system module. The hot water system module includes a heating system and a heat storage incubator. The heating system is connected to the heat storage incubator; The cold water system module includes a refrigeration system and a cold water storage incubator, and the refrigeration system is connected to the cold water storage incubator; the water mixing system module includes a water mixing valve, and a water pump is installed on the outlet pipe of the water mixing valve. A flow regulator is installed behind the water pump, and a water temperature control device is installed on the water pump;

The experimental rectification system includes a rectification box, and a plurality of rectification plates are arranged inside the rectification box;

The experimental demonstration system includes a tracer storage box, a tracer guide tube is installed at the bottom of the tracer storage box, a tracer regulating valve is installed on the tracer guide tube, and the tracer guide tube is equipped with a tracer regulating valve. The other end of the tracer guide pipe is connected to the transparent insulating glass pipe section, and a control valve is installed on the transparent insulating glass pipe section;

The water body circulation system includes a tail water tank, the tail water tank is located directly below the end of the transparent insulating glass pipe section, a sensitive thermometer is arranged inside the tail water tank, and a circulation pipe is connected to the bottom of the tail water tank, and the circulation pipe is A first control valve, a water pump, a water diversion valve and a second control valve are installed in sequence, and a water tank is arranged at the water outlet end of the circulation pipe.

The water mixing valve adopts a thermostatic water mixing valve, which can automatically maintain the set outlet water temperature within a small range.

The outside of the hot water storage incubator and the cold water storage incubator is wrapped with thermal insulation materials.

The rectifier box is flexibly connected with the flow regulator; two parallel and upright rectifier plates are arranged in the rectifier box.

The transparent insulating glass pipe section adopts a transparent glass pipe containing a heat insulating layer.

The water inlet pipe of the heating system is provided with a third control valve.

The water inlet pipe of the refrigeration system is provided with a fourth control valve.

An improved Renault tester provided by the utility model has the beneficial effects compared with the traditional Renault tester in that:

Using the change of water temperature, the purpose of adjusting the viscosity coefficient of water body movement instead of adjusting the flow velocity of the circular pipe through the change of flow rate and then changing the Reynolds number between laminar flow and turbulent flow effectively reduces the influence of water flow disturbance and improves the accuracy of the experiment.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further described.

Figure 1 is a structural unit diagram of the Renault experimental instrument.

Figure 2 is a schematic diagram of the overall water circulation system.

In the figure: heating system 1, hot water storage incubator 2, refrigeration system 3, cold water storage incubator 4, water mixing valve 5, water temperature control device 6, tracer storage box 7, tracer regulating valve 8, indicator Tracer diversion pipe 9, rectifier box 10, transparent insulating glass pipe section 11, flow regulator 12, tail water tank 13, first control valve 14, water pump 15, diverter valve 16, circulation pipe 17, control valve 18, Sensitive thermometer 19, flexible pipe 20, rectifying plate 21, water tank 22, the 4th control valve 23, the 3rd control valve 24.

Detailed ways

Embodiments of the present utility model will be further described below in conjunction with the accompanying drawings.

Example 1:

As shown in Figure 1, a new type of Reynolds experimental instrument consists of a water temperature control system, an experimental rectification system, an experimental demonstration system and a water circulation system. In particular, the water temperature control system is used to change the temperature of the experimental water body to adjust the Reynolds number; the water temperature control system includes a hot water system module, a cold water system module, and a water body mixing system module.

Wherein, the hot water system module includes a heating system 1 and a heat storage incubator 2, and the heating system 1 and the heat storage incubator 2 are internally connected with a plastic circular pipe, and the heating system 1 is used to heat up the incoming water , and then stored in the hot water storage incubator 2 to ensure sufficient and stable hot water supply; The plastic circular tubes are internally connected. Firstly, the cooling system 3 is used to cool down the incoming water, and then stored in the cold water incubator 4. When the experiment does not require special refrigeration, that is, when the fluctuation range of the Reynolds number is small, the external room temperature water can be directly used . The water body of the external normal temperature water system flows into the heating system 1 and the cooling system 3 respectively through the plastic round pipe; after the heating system 1 or the cooling system 3 is not turned on, it flows into the hot water storage tank 2 and the cold storage tank 4 respectively.

Further, the water body mixing system module is composed of a water mixing valve 5 , a flow regulator 12 , a water pump 15 and a water temperature control device 6 . The water mixing valve 5 communicates with the hot water storage incubator 2 and the cold water storage incubator 4 through the circulation pipe 17, and the water temperature control device 6 is used to set the confluence temperature of the water mixing valve to mix hot water and cold water into the required water temperature; the water pump 15 Water pressure is provided, and flow regulator 12 controls the water volume.

In addition, the experimental rectification system is composed of a rectification box 10 and a rectification plate 21 . Inside the rectifier box 10, there are two parallel rectification plates 21 placed vertically to provide a stable and constant water flow environment; special attention should be paid to the flexible connection between the rectifier box 10 and the upper flow regulator 12 using a flexible hose 20, that is, to ensure the experimental rectification demonstration The system is independent and stable, and the stability of the rectifier box 10 is not disturbed by the vibration of other connected equipment.

Further, the experimental demonstration system is composed of a tracer storage box 7 , a tracer guide tube 9 , a tracer regulating valve 8 , a transparent insulating glass pipe section 11 and a control valve 18 . The tracer storage box 7 and the tracer guide pipe 9 are placed on the transparent insulating glass pipe section 11, and the connection between the transparent insulating glass pipe section 11 and the rectifier box 10 is connected in a trumpet shape; the transparent insulating glass pipe section 11 needs to meet the heat preservation requirements , to facilitate the observation of experimental phenomena and reduce the heat loss of the water body.

Further, the water body circulation system is composed of a tail water tank 13 , a sensitive thermometer 19 , a water pump 15 and a diversion valve 16 . The tail water tank 13 and the water pump 15 are connected by a circulation pipe 17, and the first control valve 14 is set in the middle of the pipe. After the water pump, the circulation pipe 17 is connected to the diverter valve 16. During the demonstration experiment of a single Renault experimental system, there is no whole In the external hot water circulation system of the laboratory, one end of the water diversion valve 16 is connected to the heating system 1 with a plastic pipe, and the other end is connected to the water tank 22, which stores excess tail water; One end of the water valve 16 is connected to the heating system 1 of this Renault tester with a plastic tube, and the other end is connected to the external hot water circulation system of the entire laboratory. The external hot water circulation system is directly connected to the next Renault tester with a plastic round tube. The water inlet pipe of the heating system 1 of the instrument. In the water body circulation system, the tail water tank 13 collects the experimental tail water. When the water storage in the tail water tank 13 reaches a certain amount, the water diversion valve 16 is opened to connect to the hot water system end, and the water pump 15 is used to pump the tail water to the hot water circulation of the experimental incoming water. In the system, the heating system 1 is used to process again to complete the hot water cycle, and the other end of the water diversion valve 16 treats the excess tail water separately depending on whether a single or multiple experimental systems are connected. In addition, a sensitive thermometer 19 is installed in the tail water tank to check the temperature of the experimental water flow. The experimental temperature is the average value of the temperature set by the mixing valve and the monitored temperature of the tail water.

Example 2:

As shown in Figure 1, it is a structural unit diagram of the Renault experimental instrument of the present invention, which includes a water temperature control system, an experimental rectification system, an experimental demonstration system and a water body circulation system. The water temperature control system includes a heating system 1 and a hot water system module composed of a hot water storage incubator 2; a cooling system 3 and a cold water system module composed of a cold water incubator 4; a water mixing valve 5, a flow regulator 12, and a pump 15 And the water body mixing system module that water temperature control device 6 constitutes. The hot water storage and cold water storage incubators are all sealed incubators with a size of 100×60×80cm, and the mixing valve is a temperature-sensitive thermostatic mixing valve.

The experimental rectification system includes a rectification box 10 and a rectification plate 21; the rectification box 10 is made of tempered glass with a size of 100×30×60cm, and two opposing and parallel rectification plates are arranged in the rectification box at an interval of 30cm, and the size of the rectification plate is 5×30× 60cm, the rectifier box 10 and the flow regulator 12 are flexibly connected by a hose with a diameter of 30mm.

The experimental demonstration system consists of a tracer storage box 7, a tracer diversion tube 9, a tracer adjustment valve 8, a transparent insulating glass pipe section 11 and a control valve 18; the tracer storage box unit 7 is made of permanganate Potassium tracer, the end of the tracer guide tube 9 is located on the center line of the transparent insulating glass pipe section 11, and is 20cm away from the outlet of the rectifier box 10; The insulating glass pipe section 11 adopts a double-layer transparent hollow insulating glass pipe with a length of 100 cm, an outer diameter of 35 mm, and an inner diameter of 30 mm. The water circulation system is composed of a tail water tank 13 , a first control valve 14 , a water pump 15 and a diversion valve 16 .

Example 3:

As shown in Figure 2, the experimental flow of the Renault experimental instrument of the present invention is demonstrated with the schematic diagram of the overall water circulation system. Open the fourth control valve 23 and the third control valve 24 of the water inlet to connect the external cold water system with the cold water system module and the hot water system module, so that the incoming water is stored in the corresponding hot water storage insulation box, through the heating system 1 and the refrigeration system 3 respectively. Cold water storage insulation box; in the water mixing system module, adjust the temperature of the water temperature control device 6 to set the temperature, use the water mixing valve to mix the hot water storage and cold storage water into constant temperature water, and pump it to the experimental rectification demonstration module through the water pump 15; In the experimental module, the water at a specific temperature rectified by the rectifier box merges with the tracer, flows through the transparent insulating glass pipe section 11, and collects in the tail water tank 13; when the tail water tank has a certain amount of water, the water pump 15 is turned on to collect the tail water The experimental water of the module is pumped to the hot water system module for recycling. If multiple Renault experimental instruments are jointly demonstrated, the water diversion valve 16 can also be adjusted, and the outlet control valve 25 can be opened to divert the water into the water tank 22.

In the first stage of the experiment, the Reynolds number was demonstrated from low to high. Control the flow regulator 12 in the water mixing system module to adjust the flow, slightly open the tracer valve, and you can see that the colored liquid in the pipe presents a thin straight line, indicating that the flow state is laminar flow; gradually open the large flow regulator Valve, stop adjusting the flow rate from small to large corresponding to the flow rate of the circular tube determined by the Reynolds number 1800±200, keep the current adjustment setting of the flow regulator 12; start to gradually adjust the setting temperature of the water temperature control device 6, you can observe the colored straight line in the glass tube The pulsation begins to appear, but the fluid particles have not yet reached the degree of mutual exchange. At this time, it is the upper critical state where the fluid flow state begins to change. Record the experimental temperature at this moment, and the actual Reynolds number for the water flow to change from laminar flow to turbulent flow can be obtained; Continue to slowly adjust the set temperature of the water temperature control device 6. It can be observed that the colored straight line is completely disordered, and the water body flow state enters the turbulent stage. Continue to adjust the water temperature control device 6 to stop adjusting when the temperature of the water body determined by the Reynolds number 3000±200; readjust The flow regulator 12 in the water mixing system module turns up the flow.

In the second stage of the experiment, the Reynolds number was demonstrated from high to low. Control the flow regulator 12 in the water mixing system module to adjust the flow rate, and stop the adjustment when the flow rate from large to small corresponds to the circular pipe flow rate determined by the Reynolds number 3000±200, and keep the current flow regulator 12 adjustment setting; start to adjust the water temperature control device 6 The set temperature of the water flow was observed to change from turbulent flow to laminar flow, and the actual Reynolds number of water flow changed from turbulent flow to laminar flow could be solved by recording the experimental temperature at this moment; continue to adjust the set temperature of water temperature control device 6, test the A thin straight line will appear in the tube again, and the fluid flow state will change to laminar flow; stop adjusting when the temperature of the water body calculated according to the Reynolds number of 1800±200 is reached, and readjust the flow regulator 12 in the water mixing system module to reduce the flow , ready for the next experiment.

Through the above description, those skilled in the art can make various changes and modifications without departing from the technical idea of the utility model, all of which are within the protection scope of the utility model. Unfinished matters of the utility model belong to the common knowledge of those skilled in the art.

Claims (7)

1. A Renault experimental instrument, characterized in that: it comprises a water temperature control system, an experimental rectification system, an experimental demonstration system and a water circulation system; The water temperature control system is composed of a hot water system module, a cold water system module and a water mixing system module. The hot water system module includes a heating system (1) and a heat storage insulation box (2). The heating system (1) It is connected with the hot water storage insulation box (2); the cold water system module includes a refrigeration system (3) and a cold water storage insulation box (4), and the refrigeration system (3) is connected with the cold water storage insulation box (4); The water mixing system module includes a water mixing valve (5), a water pump (15) is installed on the water outlet pipe of the water mixing valve (5), and a flow regulator (12) is installed after the water pump (15). A water temperature control device (6) is installed on the water pump (15); The experimental rectification system includes a rectification box (10), and a plurality of rectification plates (21) are arranged inside the rectification box (10); The experimental demonstration system includes a tracer storage box (7), and a tracer guide tube (9) is installed at the bottom of the tracer storage box (7), and the tracer guide tube (9) A tracer regulating valve (8) is installed on the top, and the other end of the tracer guide pipe (9) is connected to the transparent insulating glass pipe section (11), and a control valve is installed on the transparent insulating glass pipe section (11) (18); The water circulation system includes a tail water tank (13), the tail water tank (13) is located directly below the end of the transparent insulating glass pipe section (11), and a sensitive thermometer (19) is arranged inside the tail water tank (13), The bottom of the tail water tank (13) is connected with a circulation pipe (17), and the circulation pipe (17) is sequentially installed with a first control valve (14), a suction pump, a diverter valve (16) and a second control valve ( 25), the water outlet end of the circulation pipe (17) is provided with a water tank (22). 2. A Renault tester according to claim 1, characterized in that: the water mixing valve (5) is a thermostatic water mixing valve, which can automatically maintain the set outlet water temperature within a small range. 3. A Renault tester according to claim 1, characterized in that: the heat-storage incubator (2) and the cold-storage incubator (4) are wrapped with heat-insulating materials. 4. A Renault tester according to claim 1, characterized in that: the rectifier box (10) and the flow regulator (12) are flexibly connected by a hose (20); two blocks are arranged in the rectifier box Parallel upright rectifying plates (21). 5. A Renault tester according to claim 1, characterized in that: the transparent insulating glass tube section (11) is a transparent glass tube with a thermal insulation layer. 6. A Renault tester according to claim 1, characterized in that: the water inlet pipe of the heating system (1) is provided with a third control valve (24). 7. A Renault tester according to claim 1, characterized in that: a fourth control valve (23) is provided on the water inlet pipe of the refrigeration system (3).