Liquid nitrogen cooling type simulated rainfall experiment teaching aid

Abstract

The utility model discloses a kind of liquid nitrogen cooling type simulated rainfall experiment teaching aids, including experiment box and the top cover plate of experiment box top setting, experiment box is present and can be seen through cuboid box, and top surface is full opening design, and water injection port is used to inject cold water or hot water simulation ground water in the bottom of experiment box right side;Top cover plate covers the top surface opening of experiment box, and the lower surface of top cover plate is equipped with the liquid nitrogen spray pipe of arc shape with longitudinal opening, and cotton ball is covered outside the longitudinal opening of liquid nitrogen spray pipe;The input end of liquid nitrogen spray tank and liquid nitrogen spray pipe is detachably connected, which is independently arranged outside experiment box;The utility model is visible by transparent box body design and detachable modular structure, simulate precipitation phenomenon, convert abstract water cycle thermodynamic principle into visual natural phenomenon;By independently adjusting injection cold water or hot water, and control and adjust liquid nitrogen injection state, i.

Description

TECHNICAL FIELD

[0001] The utility model relates to rainfall simulation technical field especially relates to a liquid nitrogen cooling formula simulation rainfall experiment teaching aid. BACKGROUND

[0002] Precipitation observation is one of the important elements in ground meteorological observation, and mastering precipitation intensity identification skills and understanding the relationship between precipitation observation and wind and temperature are one of the difficulties in teaching. The formation of simulated rainfall is a compulsory experiment in the basic directory of primary and secondary school experimental teaching, and the traditional experiment is to use the water vapor emitted by hot water in the beaker under the tripod to collide with the bottom of the iron plate containing ice on the top of the tripod, and the water droplets are condensed on the lower surface of the iron plate and fall down, simulating the natural phenomenon of rainfall formation.

[0003] This traditional experimental method only shows the combination of evaporation and condensation two phenomena, and cannot guide students to understand that temperature is an internal factor for promoting rainfall formation, cannot comprehensively master the reasons for rainfall formation and water cycle formation in nature, and restricts the cultivation of students' scientific thinking.

[0004] Therefore, a liquid nitrogen cooling formula simulation rainfall experiment teaching aid is provided to solve the above problems. UTILITY MODEL CONTENT

[0005] In order to solve the above problems existing in the prior art, the utility model provides a liquid nitrogen cooling formula simulation rainfall experiment teaching aid.

[0006] The technical scheme of the utility model is as follows:

[0007] A liquid nitrogen cooling formula simulation rainfall experiment teaching aid, comprising an experimental box and a top cover plate arranged on the top of the experimental box, the experimental box is a perspective cuboid box, and the top surface is designed as a full opening, a water inlet is arranged on the right bottom of the experimental box for injecting cold water or hot water to simulate ground water; the top cover plate covers the top opening of the experimental box, and the lower surface of the top cover plate is provided with an arc-shaped liquid nitrogen spray pipe with a longitudinal opening, and the longitudinal opening of the liquid nitrogen spray pipe is covered with cotton balls; the outside of the experimental box is independently provided with a liquid nitrogen spray tank, and the input end of the liquid nitrogen spray pipe is detachably connected.

[0008] Preferably, the liquid nitrogen spray pipe is an arc-shaped downward-bent thin plastic pipe, two longitudinal openings are arranged at the bottom to uniformly diffuse the liquid nitrogen gas to the surface of the cotton balls to form a low-temperature condensation zone.

[0009] Preferably, the water inlet is arranged on the outer wall of the right bottom of the experimental box, and the position is higher than the inner plane of the bottom of the box to avoid direct flushing of the water flow to the cotton balls.

[0010] Preferably, the cotton balls tightly wrap the longitudinal opening of the liquid nitrogen spray pipe, and the cotton balls can be used to adsorb water vapor and sublimate ice crystals by using the fragrance structure of the cotton balls.

[0011] The utility model has the advantages that: the utility model discloses through transparent box body design and detachable modular structure, students can directly observe the dynamic process that water vapor is condensed into ice crystal under the refrigeration of liquid nitrogen on the surface of cotton ball, namely, the simulated precipitation phenomenon can be seen, and the abstract water cycle thermodynamic principle is converted into visual natural phenomenon, by independently adjusting the injection of cold water or hot water, and controlling and adjusting the liquid nitrogen injection state, that is, opening or closing, students can independently design four sets of contrast experiments, and the double mechanism that temperature simultaneously regulates evaporation and condensation rate is accurately verified, this structured variable matrix design realizes the complete attribution deduction of "the necessary condition of rainfall formation" at the teaching aid level for the first time, makes students deeply understand the decisive role of temperature in the water cycle in nature, avoids the defects of long time consumption and vague phenomenon of traditional teaching aids, internalizes thermodynamic concepts into scientific thinking accomplishment, and significantly enhances the depth and practicality of environmental science education. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is whole structure schematic diagram of the utility model;

[0013] The figure mark is shown as:

[0014] 1, experimental box, 2, water inlet, 3, liquid nitrogen spray tank, 4, top cover, 5, liquid nitrogen spray pipe, 6, cotton ball. DETAILED DESCRIPTION

[0015] The technical scheme in the embodiments of the utility model will be apparently and completely described below with reference to the drawings in the embodiments of the utility model. Apparently, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the utility model.

[0016] Reference is made to Figure 1 A liquid nitrogen cooling type simulated rainfall experiment teaching aid, including experimental box 1 and the top cover plate 4 of experimental box 1 top, experimental box 1 is the perspective cuboid box body, and the top surface is the full opening design, is equipped with water inlet 2 for injecting cold water or hot water simulation ground water at the right bottom of experimental box 1;The top cover plate 4 covers the top surface opening of experimental box 1, and the lower surface of top cover plate 4 is provided with the liquid nitrogen spray pipe 5 of arc-shaped with longitudinal opening, and the longitudinal opening of liquid nitrogen spray pipe 5 is covered with cotton ball 6;The outside of experimental box 1 is independently provided with liquid nitrogen spray tank 3 and the input end detachable connection of liquid nitrogen spray pipe 5.

[0017] In the utility model, the experimental box (1), top cover plate (4) and liquid nitrogen spray tank (3) are detachable independent modules, and can be combined to form a closed experimental system.

[0018] Further, the liquid nitrogen spray pipe 5 is an arc-shaped downward-bent thin plastic pipe, and two longitudinal openings are formed in the bottom of the pipe to uniformly diffuse the liquid nitrogen gas to the surface of the cotton ball 6 to form a low-temperature condensation zone.

[0019] Further, the water injection opening 2 is arranged at the bottom outer wall of the right side of the experiment box 1 and is higher than the inner plane of the bottom of the box.

[0020] Further, the cotton ball 6 tightly wraps the longitudinal opening of the liquid nitrogen spray pipe 5 to absorb water vapor and condense ice crystals.

[0021] The working principle of the utility model is as follows:

[0022] In the utility model, the following teaching method for simulating rainfall is adopted, and the steps are as follows:

[0023] S1, water injection control: hot water or cold water is injected through the water injection opening 2;

[0024] S2, liquid nitrogen refrigeration: the liquid nitrogen spray can 3 is pressed to spray liquid nitrogen gas to the cotton ball 6 at a preset interval;

[0025] S3, comparative experiment: four groups of variable combinations are operated:

[0026] (a) inject cold water + do not spray liquid nitrogen;

[0027] (b) inject cold water + spray liquid nitrogen;

[0028] (c) inject hot water + do not spray liquid nitrogen;

[0029] (d) inject hot water + spray liquid nitrogen;

[0030] S4, observation phenomenon: the formation of ice crystals on the surface of the cotton ball and the falling of water droplets within 90 seconds are recorded to verify the double influence of temperature on the formation of rainfall.

[0031] Among them, the liquid nitrogen spraying interval is 5 seconds / time, and visible ice crystals are formed on the surface of the cotton ball 6 after 1 minute of continuous operation, and significant rainfall phenomenon can be produced after 90 seconds.

[0032] The experimental data table is as follows:

[0033]

[0034] Through the experimental exploration results, it is understood that temperature is an important internal factor affecting the formation of rainfall and water cycle.

[0035] The experimental conclusion analysis is as follows:

[0036] Comparative experiment group one and experiment group four: it is proved that the evaporation (hot water) and condensation (liquid nitrogen) are necessary conditions for rainfall;

[0037] Experiment group two condensation deficiency: slow evaporation of cold water, even if the liquid nitrogen to produce low temperature, water vapor is insufficient to form rain;

[0038] Experiment group three evaporation invalid: hot water evaporates fast, but no low-temperature condensing carrier, steam cannot be liquefied into rain;

[0039] Core mechanism: temperature controls water circulation through double paths, that is, when the surface water temperature rises, the evaporation rate accelerates; when the cloud temperature drops, the condensation rate accelerates.

[0040] The above only describes the embodiments of the present application, and does not limit the patent range of the present application, and any equivalent structure or equivalent process transformation using the content of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection range of the present application.

Claims

1. A liquid nitrogen cooling-type simulated rainfall experimental teaching aid, comprising an experimental box (1) and a top cover plate (4) disposed on the top of the experimental box (1), characterized in that: The experimental box (1) is a transparent rectangular box with a fully open top surface. A water inlet (2) is provided at the bottom right side of the experimental box (1) for injecting cold or hot water to simulate surface water. The top cover (4) covers the top opening of the experimental box (1), and the lower surface of the top cover (4) is provided with an arc-shaped liquid nitrogen spray pipe (5) with a longitudinal opening. The longitudinal opening of the liquid nitrogen spray pipe (5) is covered with cotton balls (6). The outside of the experimental box (1) is independently provided with a liquid nitrogen spray tank (3) which is detachably connected to the input end of the liquid nitrogen spray pipe (5).

2. The liquid nitrogen cooling simulated rainfall experimental teaching aid according to claim 1, characterized in that: The liquid nitrogen nozzle (5) is an arc-shaped, downward-curved thin plastic tube with two longitudinal openings at the bottom, so that the liquid nitrogen gas can be evenly diffused to the surface of the cotton ball (6) to form a low-temperature condensation zone.

3. The liquid nitrogen cooling simulated rainfall experimental teaching aid according to claim 1, characterized in that: The water inlet (2) is located on the outer wall of the bottom right side of the experimental chamber (1), and its position is higher than the inner plane of the bottom of the chamber.

4. The liquid nitrogen cooling simulated rainfall experimental teaching aid according to claim 1, characterized in that: The cotton ball (6) tightly wraps the longitudinal opening of the liquid nitrogen nozzle (5) to adsorb water vapor and sublimate ice crystals.

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