阅读说明：本技术 一种水泵汽蚀现象实验装置 (Water pump cavitation phenomenon experimental device ) 是由 刘坤 李媛媛 马帅 于 2021-06-12 设计创作，主要内容包括：本发明的水泵汽蚀现象实验装置主要分为三部分,分别为控制部分,水源及循环管道部分,实验发生部分。各部分集中在一个与水平面平行的矩形底座支架上,水源水箱中装有加热器和冷凝装置,以及温度传感器,可以实验不同温度下的液体产生的汽蚀对水泵的影响。控制箱位于整个实验装置的后方,方便控制的同时不影响实验的进行,控制箱不但能控制水泵的启动,还可以控制水泵的转速,并把转速显示在控制箱上对应显示器上；还可以改变水源水箱加热温度,并显示当前水箱的水温。实验水泵入水口和出水口装有压力表和球阀,可测量流量变化过程中水泵发生汽蚀现象时压力变化情况,水泵使用透明泵头,可以更直观的观察汽蚀发生的全过程。(The water pump cavitation phenomenon experimental device is mainly divided into three parts, namely a control part, a water source and circulating pipeline part and an experiment generation part. All parts are concentrated on a rectangular base support parallel to the horizontal plane, and a heater, a condensing device and a temperature sensor are arranged in a water source water tank, so that the influence of cavitation generated by liquid at different temperatures on a water pump can be tested. The control box is positioned behind the whole experimental device, so that the control is convenient, the experiment is not influenced, the control box can control the starting of the water pump and the rotating speed of the water pump, and the rotating speed is displayed on a corresponding display on the control box; the heating temperature of the water source water tank can be changed, and the current water temperature of the water tank can be displayed. The water inlet and the water outlet of the experimental water pump are provided with the pressure gauge and the ball valve, so that the pressure change condition of the water pump in the flow change process can be measured, and the water pump uses the transparent pump head, so that the whole process of cavitation can be observed more visually.)

1. A kind of water pump cavitation phenomenon experimental provision, fig. 1 is the control box, 3 is the water source water tank, 4 is the experimental water pump, show the common part shape here only, obviously can also use other part of suitable shape; the device comprises a water source water tank 3, a water outlet of an experimental water pump 4, a filter 9 for filtering impurities in a water source and a ball valve 14 for controlling inflow, wherein the water inlet is also provided with a pressure gauge 10 for detecting the pressure without cavitation when the experiment starts; the water outlet is also provided with a pressure gauge 11, and after the water pump 4 generates cavitation, the indication number of the water pump is compared with that of the pressure gauge 10, so that the pressure change condition before and after the cavitation is calculated; besides, the pipeline at the water outlet is also connected with a ball valve 13 for controlling the flow of the water outlet, a flow meter 2 for checking the flow change, and finally a water return tank to realize circulation.

2. The water pump cavitation experiment apparatus of claim 1, wherein: the experiment water pump 4 base can install the cushion additional, and quantity can be self-defined.

3. The water pump cavitation experiment apparatus of claim 1, wherein: the control box 1 can control the temperature of the water source water tank 3 and the rotating speed of the experimental water pump 4.

4. The water pump cavitation experiment apparatus of claim 1, wherein: and a filter 9 is arranged at the water outlet of the water source water tank 3.

5. The water pump cavitation experiment apparatus of claim 1, wherein: and a liquid level display device 12 based on a communicating vessel principle is arranged on the side edge of the water source water tank 3.

6. The water pump cavitation experiment apparatus of claim 1, wherein: the base support 5 is additionally provided with a portable handle 6.

7. The water pump cavitation phenomenon experiment apparatus as set forth in claims 1 and 2, characterized in that: the experimental water pump 4 used a transparent pump head 12.

Technical Field

The invention relates to a practical training experimental device, in particular to a demonstration device for cavitation generated when a water pump works.

Background

The cavitation of the water pump refers to the process of water flow component damage and water power performance deterioration caused by the fact that air bubbles in a low-pressure area in a water pump overflowing system are quickly collapsed when water flow reaches a high-pressure area and is compressed.

When the effective cavitation allowance of the water pump device is smaller than the necessary cavitation allowance of the water pump, and the local pressure in the pump is reduced to the saturated vaporization pressure at the liquid temperature, gas nuclei existing in the gaps of impurities, tiny solid particles or liquid interfaces (contact surfaces of liquid and solid) in the liquid rapidly grow into cavitation bubbles and reach a high-pressure area along with water flow, and are rapidly collapsed by the compression of surrounding liquid. In the cavitation collapse area, the metal surface bears a water hammer force, the frequency of the water hammer force can reach several ten thousand times per second, and the water hammer force acts on a tiny area, so that the stress of the water hammer force can reach thousands of atmospheric pressures. Such high stress frequently applied causes plastic deformation and hardening of the metal surface layer, producing local fatigue and micro-cracks, the latter promoting the development of cavitation. Causing the metal component to be broken and peeled. Cavitation can occur on the back and front faces of the impeller blades, as well as between the outer edge of the impeller and the wall of the impeller chamber. In general, the cavitation of a water pump reduces the flow, the lift, the power and the efficiency of the pump, causes the vibration and the noise of a unit, shortens the service life of equipment, and influences the engineering safety. The situation is more serious in a water pump for taking water from water flow with high sand content

When bubbles are fed and extinguished, liquid particles collide with each other to generate noise, when cavitation is serious, vibration is generated, flow, lift and efficiency are obviously reduced, even evacuation phenomenon occurs, and meanwhile, the impeller is degraded and thinned due to cavitation, even the blades and the cover plate are penetrated. The cavitation causes the water pump performance to deteriorate, the device operates unstably, the metal surface material is tired and is degraded, noise and vibration aggravate etc. bad consequence, therefore, need analysis, research and monitoring water pump cavitation in design and operation management, in time take effective safeguard measure.

Disclosure of Invention

The invention aims to: the device can be used for observing and knowing the cavitation phenomenon of the water pump and the influence on the working performance of the water pump, and knowing main factors influencing the cavitation of the water pump and measures for preventing the cavitation.

The water pump cavitation phenomenon experimental device is mainly divided into three parts, namely a control part, a water source and circulating pipeline part and an experiment generation part. All parts are concentrated on a rectangular base support parallel to the horizontal plane, and a heater, a condensing device and a temperature sensor are arranged in a water source water tank, so that the influence of cavitation generated by liquid at different temperatures on a water pump can be tested. The control box is positioned behind the whole experimental device, so that the control is convenient, the experiment is not influenced, the control box can control the starting of the water pump and the rotating speed of the water pump, and the rotating speed is displayed on a corresponding display on the control box; the heating temperature of the water source water tank can be changed, and the current water temperature of the water tank can be displayed. The water inlet and the water outlet of the experimental water pump are provided with the pressure gauge and the ball valve, so that the pressure change condition of the water pump in the flow change process can be measured, and the water pump uses the transparent pump head, so that the whole process of cavitation can be observed more visually.

Drawings

FIG. 1 is a schematic diagram of the overall structure of a water pump cavitation experiment device.

FIG. 2 is a schematic diagram of a control box of the water pump cavitation experiment device.

Fig. 3 shows a left side view of the water pump cavitation experiment apparatus.

FIG. 4 is a schematic diagram of the internal structure of a water tank of the experimental device for water pump cavitation.

Detailed Description

The invention is described in detail below with reference to the drawings and the detailed description.

In fig. 1, reference numeral 1 is a control box, 3 is a water source tank, and 4 is an experimental water pump, and only the common shapes of the components are shown here, and obviously, other components with appropriate shapes can be used; the water source water tank 3 is connected to the water inlet of the experimental water pump 4, the middle of the water source water tank is provided with a filter 9 for filtering impurities in a water source and a ball valve 14 for controlling the water inlet flow, and the water inlet is also provided with a pressure gauge 10 for detecting the pressure without cavitation when the experiment starts; the water outlet is also provided with a pressure gauge 11, and after the water pump 4 generates cavitation, the indication number of the water pump is compared with that of the pressure gauge 10, so that the pressure change condition before and after the cavitation is calculated; besides, the pipeline at the water outlet is also connected with a ball valve 13 for controlling the flow of the water outlet, a flow meter 2 for checking the flow change, and finally a water return tank to realize circulation.

Fig. 2 shows a control box part, as shown in the control box 1, the control box 1 is a rectangular cube structure as a whole, and is installed behind all experimental devices, so that the experiment is not influenced while the adjustment is convenient; the control box 1 not only plays a role in control, but also can display the accurate numerical values of all sensors in an experiment and the specific rotating speed of the water pump 4; at the beginning of the experiment; the main power switch 26 and the water pump starting switch 28 are turned on, and at the moment, the temperature controller 21, the flow meter 22 and the tachometer 25 display the numerical values of the corresponding sensors; the heating switch 23 is connected with the heater 7 and is used for changing the temperature of the liquid in the water source tank 3; the rotational speed controller 29 changes the rotational speed of the water pump 4 so as to observe the change of the rotational speed of the water pump 4 to the cavitation phenomenon.

Referring to fig. 3 and 4, the side of the water source tank 3 is provided with an inlet 30 and an outlet 31 of a cooling coil 35, and in addition, a drain outlet 32 is arranged below the side; cooling coil 35 inside the tank is mounted in a manner referring to fig. 4, with heater 7 and temperature sensor 8 opposite cooling coil 35.