Gas internal energy change demonstrator

Abstract

The utility model discloses a gas internal energy change demonstrator, and relates to the technical field of teaching tools. The demonstrator structurally comprises an air cylinder, the air cylinder is connected with an inflating device through a first sealing pipeline, and the demonstrator further comprises a circuit control system, a temperature indicating device used for indicating the temperature in the air cylinder and a pressure indicating device used for indicating the pressure in the air cylinder. According to the utility model, the structural design is reasonable, the problems that the traditional teaching aid has many parts and raw materials have certain dangerousness are solved, the direct relationship between gas acting and internal energy change is more visually reflected through the temperature indicating device and the pressure indicating device, and a demonstrator is helped to display the gas internal energy change more vividly.

Description

Technical Field

[0001] The present application relates to the technical field of teaching tools, and in particular to a gas internal energy change demonstrator. Background Art

[0002] Internal energy is the sum of the kinetic energy of all the molecules in the object and the potential energy of the molecules. When work is done on an object, the internal energy of the object increases; when work is done on the object, the internal energy of the object decreases. In order to combine experiments to let students understand the law of mechanical energy and internal energy conversion, the existing demonstration experiment uses two teaching aids. One teaching aid is Figure 1 As shown in the figure, nitrocellulose is ignited by compressing gas to demonstrate that work is done on the gas to increase the internal energy of the gas (the temperature rises). Another teaching aid is Figure 2 As shown, the cork is opened by the pressurized gas, and water mist is condensed in the bottle to demonstrate that the gas does work outside and reduces its internal energy (lowers its temperature).

[0003] However, the current teaching aids have at least the following problems: 1. Two teaching aids are required for demonstration, which is cumbersome to operate, has many parts, is easy to lose, and takes a long time to prepare. 2. Nitrocellulose is flammable, and the experiment is somewhat dangerous. 3. It is difficult to obtain condensed water mist in actual experiments. Even if water mist appears by chance, it is difficult for students sitting under the podium to observe it. Utility Model Content

[0004] The technical problems to be solved by the utility model are that the teaching aids have many parts, the experimental materials are dangerous, and it is difficult to observe the phenomenon of water vapor condensing into liquid. For this reason, the utility model provides a device which integrates two teaching aids and their parts, is non-dangerous, and can more intuitively observe the work done by gas and the change of internal energy.

[0005] In order to solve the above technical problems, the utility model provides a gas internal energy change demonstrator, including a gas cylinder, the gas cylinder is connected to an air pumping device through a first sealed pipe, and the gas internal energy change demonstrator also includes a circuit control system, a temperature indicating device for indicating the temperature in the gas cylinder, and a pressure indicating device for indicating the pressure in the gas cylinder. The gas used to demonstrate the change in gas internal energy is stored in a sealed gas cylinder, and the pressure indicating device reflects the gas pressure in the gas cylinder. The change in the gas pressure value can reflect the work done by the gas to the outside or the work done by the outside to the gas; the temperature indicating device reflects the gas temperature, and the change in gas temperature can reflect the change in gas internal energy. The circuit control system controls the temperature indicating device, the pressure indicating device, the air pumping device, the protection device and other devices connected to the circuit.

[0006] Furthermore, as one of the preferred modes of the gas internal energy change demonstrator: the gas storage cylinder is connected to the observation device through a second sealed pipe, the second sealed pipe is provided with an air release valve, the observation device is a transparent piston cylinder, and the transparent piston cylinder is equipped with a foam ball that can move with the flow of gas. The observation device is used to directly observe the work done by gas release, and the number of foam balls must not fill the transparent piston cylinder, and the number of foam balls is preferably sufficient to facilitate the observation of the gas blowing up the foam balls. The foam balls in the transparent piston cylinder are blown up by the gas, which can visualize the form of gas doing work externally. Combined with the temperature indicating device, it can also reflect the work done by the gas and the reduction of internal energy.

[0007] Furthermore, as one of the preferred modes of the gas internal energy change demonstrator: the temperature indicating device includes a temperature sensor and a temperature numerical display that changes dynamically in real time according to the temperature in the gas cylinder. The temperature sensor probe senses the gas temperature in the gas cylinder, and the temperature numerical display displays the real-time temperature, thereby reflecting the internal energy change of the gas in the gas cylinder. The temperature numerical display can also be changed to a temperature indicator light group, which displays the temperature range such as lower temperature, medium temperature and higher temperature.

[0008] Further, as one of the preferred modes of the gas internal energy change demonstrator: the pressure indicating device includes a pressure sensor and a pressure indicator light group that gradually lights up or goes out according to the pressure change of the gas cylinder. The pressure sensor probe senses the gas pressure in the gas cylinder, and the pressure indicator light group gradually lights up or goes out to display the pressure change in the gas cylinder, thereby reflecting the work done by the gas in the gas cylinder.

[0009] Furthermore, as one of the preferred modes of the gas internal energy change demonstrator: the pressure indicating device includes a pressure sensor and a pressure numerical display that changes dynamically in real time according to the pressure in the gas storage cylinder. The pressure display device can also be a pressure numerical display that directly and intuitively reflects the pressure with numerical changes.

[0010] Furthermore, as one of the preferred modes of the gas internal energy change demonstrator: the air pumping device is an electric air pump, the first sealed pipe is connected to an air inlet valve, and the circuit control system controls the switch of the electric air pump and the air inlet valve to controllably adjust the pressure in the air storage cylinder.

[0011] Furthermore, as one of the preferred modes of the gas internal energy change demonstrator: the gas internal energy change demonstrator further comprises an overpressure protection device, which is an overpressure solenoid valve connected to the circuit control system. The circuit control system detects the internal air pressure of the gas storage cylinder through a pressure sensor, and opens the overpressure solenoid valve to release the pressure when the pressure exceeds the set value, thereby protecting the demonstrator.

[0012] The method of using the gas internal energy change demonstrator is as follows:

[0013] 1. Preparation before use:

[0014] Place the instrument flat on the table, check to ensure that the air storage cylinder is airtight, the transparent piston cylinder is firmly fixed, and the air outlet hole on the upper end of the transparent piston cylinder is not blocked.

[0015] Close the air vent valve, turn on the main power switch, the temperature display shows room temperature, the pressure display shows "0", and the instrument is ready.

[0016] 2. Demonstrate that work is done on a gas to increase its internal energy:

[0017] By pumping air, work is done on the gas in the gas cylinder. The gas pressure gradually increases during the work process, which can be visually seen by the observer through the pressure indicating device. At this time, the observer can also visually see the gas temperature rise through the temperature indicating device, indicating that work is done on the gas, the temperature rises, and the internal energy increases.

[0018] 3. Demonstrate that the gas does work externally and its internal energy decreases:

[0019] In the initial state, the gas in the gas cylinder has a certain initial pressure, and the initial temperature is recorded. The air release valve is quickly opened, and the compressed gas rushes up the foam ball in the transparent piston cylinder, that is, the gas does work on the foam ball. At the same time, the observer can see the temperature drop through the temperature indicating device, which means that the gas does work outside, the temperature drops, and the internal energy is reduced.

[0020] 4. Safe use:

[0021] When the gas pressure reaches the threshold, the circuit control system stops supplying power to the electric air pump and stops pumping; when the gas pressure exceeds the threshold, the overpressure solenoid valve opens to release the gas and pressure, providing double insurance to ensure the safe use of the demonstrator.

[0022] In summary, the advantages of the utility model are:

[0023] (1) The demonstrator integrates many components, making it easier and quicker for teachers to prepare for class. After the experiment, the demonstrator is easy to pack up and carry and is not likely to fall apart.

[0024] (2) There are no dangerous experimental materials, and the experimental equipment is equipped with an overvoltage protection device, which is safe and reliable and protects the lives of teachers and students.

[0025] (3) This demonstrator has a temperature indicator and a pressure indicator, which can intuitively reflect the changes in the internal energy of the gas and the work done by the gas. It is more convenient and easier to observe than the water vapor condensation in the original experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The present invention is a schematic diagram of an existing internal energy demonstration teaching aid.

[0027] Figure 2 This is a schematic diagram of another existing internal energy demonstration teaching aid.

[0028] Figure 3 This is a schematic diagram of the overall structure of this application.

[0029] Figure 4 This is a structural diagram of the present application from another angle.

[0030] Figure 5 This is a bottom exploded schematic diagram of this application.

[0031] Explanation of the reference numerals: 1. air storage cylinder; 2. first sealed pipe; 2a. air inlet valve; 3. second sealed pipe; 3a. air release valve; 3b. overpressure solenoid valve; 4. temperature numerical display; 5. air pressure indicator light group; 6. air pressure numerical display; 7. transparent piston cylinder; 8a. temperature sensor; 8b. pressure sensor. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described content cannot fully exemplify all implementation schemes. The following examples are only a part of many implementation schemes, not all examples. Based on the disclosure of the utility model, all other implementation results obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0033] Example

[0034] like Figure 3 As shown, a gas internal energy change demonstrator includes a gas storage cylinder 1, which is connected to an electric air pump through a first sealed pipe 2, and an air inlet valve 2a is also connected to the first sealed pipe 2. The gas internal energy change demonstrator also includes a circuit control system, a temperature indicating device for indicating the temperature in the gas storage cylinder 1, and a pressure indicating device for indicating the pressure in the gas storage cylinder 1.

[0035] like Figure 5 As shown, the gas storage cylinder 1 is connected to the observation device through the second sealed pipe 3, and the second sealed pipe 3 is provided with a deflation valve 3a. The observation device is a transparent piston cylinder 7, and the transparent piston cylinder 7 contains a foam ball that can move with the flow of gas.

[0036] like Figure 3 and 4 As shown, the temperature indicating device includes a temperature sensor 8a and a temperature numerical display 4 that changes dynamically in real time according to the temperature in the gas storage cylinder 1.

[0037] The pressure indicating device includes a pressure sensor 8b, an air pressure indicator light group 5 which gradually lights up or goes out according to the pressure change of the air cylinder 1, and an air pressure value display 6 which dynamically changes in real time according to the air pressure in the air cylinder 1.

[0038] The gas internal energy change demonstrator also includes an overpressure protection device, which is an overpressure solenoid valve 3b connected to the circuit control system.

[0039] Other embodiments

[0040] The temperature indicating device includes a temperature sensor and a temperature display. The temperature display can display a numerical value or can be a temperature indicator light group that gradually lights up as the temperature rises.

[0041] The air pressure indicator light group and the air pressure value display can be used at the same time, or only one air pressure display device can be used.

[0042] The work done by the gas can be observed through the transparent piston cylinder or simply from the gas pressure indicating device.

[0043] The above solutions can be arranged and combined to form the technical solution of the utility model.

[0044] The embodiments of the utility model are described in detail above in conjunction with the accompanying drawings, but the utility model is not limited to the above-mentioned implementation modes. Within the scope of knowledge possessed by ordinary technicians in the technical field, equivalent changes made to the structure, shape and principle all fall within the protection scope of the utility model.

Claims

1. A gas internal energy change demonstrator, comprising a gas storage cylinder (1), wherein the gas storage cylinder (1) is connected to an air pumping device via a first sealed pipe (2). Features: The gas internal energy change demonstrator further comprises a circuit control system, a temperature indicating device for indicating the temperature inside the gas cylinder (1), and a pressure indicating device for indicating the pressure inside the gas cylinder (1).

2. The gas internal energy change demonstrator according to claim 1, Features: The gas storage cylinder (1) is connected to the observation device via a second sealed pipe (3), the second sealed pipe (3) is provided with a deflation valve (3a), the observation device is a transparent piston cylinder (7), and a foam ball that can move with the flow of gas is installed in the transparent piston cylinder (7).

3. The gas internal energy change demonstrator according to claim 1 or 2, Features: The temperature indicating device comprises a temperature sensor (8a) and a temperature value display (4) which changes dynamically in real time according to the temperature in the gas storage cylinder (1).

4. The gas internal energy change demonstrator according to claim 1 or 2, Features: The pressure indicating device comprises a pressure sensor (8b) and a gas pressure indicator light group (5) which gradually lights up or goes out according to the pressure change of the gas cylinder (1).

5. The gas internal energy change demonstrator according to claim 1 or 2, Features: The pressure indicating device comprises a pressure sensor (8b) and an air pressure numerical display (6) which changes dynamically in real time according to the air pressure in the air storage cylinder (1).

6. The gas internal energy change demonstrator according to claim 1, Features: The air pumping device is an electric air pump, and the first sealed pipe (2) is connected to an air inlet valve (2a).

7. The gas internal energy change demonstrator according to claim 1, Features: The gas internal energy change demonstrator further comprises an overpressure protection device, wherein the overpressure protection device is an overpressure solenoid valve (3b) connected to the circuit control system.

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