CN109448514A - Bernoulli principle demonstration instrument for teaching - Google Patents
Bernoulli principle demonstration instrument for teaching Download PDFInfo
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- CN109448514A CN109448514A CN201811617108.XA CN201811617108A CN109448514A CN 109448514 A CN109448514 A CN 109448514A CN 201811617108 A CN201811617108 A CN 201811617108A CN 109448514 A CN109448514 A CN 109448514A
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 69
- 230000006978 adaptation Effects 0.000 claims abstract description 9
- 239000012530 fluid Substances 0.000 claims abstract description 7
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 claims abstract description 3
- 239000007788 liquid Substances 0.000 claims description 15
- 238000002474 experimental method Methods 0.000 claims description 4
- 239000007921 spray Substances 0.000 claims description 4
- 239000011521 glass Substances 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 238000000034 method Methods 0.000 claims description 3
- 238000004364 calculation method Methods 0.000 claims description 2
- 238000004891 communication Methods 0.000 claims description 2
- 238000002347 injection Methods 0.000 claims description 2
- 239000007924 injection Substances 0.000 claims description 2
- 238000005516 engineering process Methods 0.000 abstract description 2
- 239000011148 porous material Substances 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09B—EDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS
- G09B23/00—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes
- G09B23/06—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics
- G09B23/08—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics for statics or dynamics
- G09B23/12—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics for statics or dynamics of liquids or gases
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- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Mathematical Analysis (AREA)
- Mathematical Optimization (AREA)
- Algebra (AREA)
- Pure & Applied Mathematics (AREA)
- Educational Administration (AREA)
- Computational Mathematics (AREA)
- Business, Economics & Management (AREA)
- Educational Technology (AREA)
- Theoretical Computer Science (AREA)
- Measuring Volume Flow (AREA)
Abstract
Bernoulli principle demonstration instrument for teaching disclosed by the invention belongs to fluid dynamics instructional technology field.The present invention includes water storage module, height adjustment fluidics module, damper modules.Three modules use Modularized dismounting structure.Water storage module includes, water storage tank, jet hole, water level regulation hole, the first cooperation slot, height adjustment fluidics module adaptation slot；First cooperation slot is adapted to the second cooperation slot；It is bar shaped in the middle part of jet hole, two sides are semicircle, and strip width is identical as comparison bore dia, and two sides are radius semicircle identical with comparison pore radius；Water level regulation hole is located at water storage tank bottom.Comparison hole is provided on height adjustment fluidics module, external shape fits height adjustment fluidics module is adapted to slot.Damper modules include front apron, side baffle, pedestal, fluerics, water level regulation matching hole, lateral graduated scale, longitudinal graduated scale, the second cooperation slot；Water level regulation matching hole longitudinal aperture is greater than water level regulation hole aperture.
Description
Technical field
The present invention relates to a kind of Bernoulli equation demonstration instrument for teaching, belong to fluid dynamics instructional technology field.
Background technique
The essence of bernoulli principle is the conservation of mechanical energy of perfect fluid, it has on a series of relevant engineering problems
Considerable application value and undergraduate learn essential a part during " hydrodynamics " course.Student exists
A kind of concrete principle of more intuitive teaching aid performance Bernoulli equation is needed during classroom learning, more clearly grasping should
The content of courses.Currently, there is no the teaching aid of intuitive performance Bernoulli equation concrete principle in the prior art.
Summary of the invention
The purpose of bernoulli principle demonstration instrument for teaching disclosed by the invention is: providing a kind of more intuitive bernoulli principle
Demonstration teaching aid, the teaching aid pass through adjustable, observable water-head H-hi, theoretical stream distance is sought obtaining using bernoulli principle
S, and the practical stream distance S ' verifying bernoulli principle tested by the teaching aid.The present invention can carry out on classroom
The sync instruction of bernoulli principle theory and experimental applications makes student have understanding more profound to this learning Content.
The object of the invention is achieved through the following technical solutions.
Bernoulli principle demonstration instrument for teaching disclosed by the invention, including water storage module, height adjustment fluidics module, baffle mould
Block.Three modules use Modularized dismounting structure.The water storage module includes, water storage tank, jet hole, water level regulation hole,
First cooperation slot, height adjustment fluidics module are adapted to slot；First cooperation slot is adapted to the second cooperation slot；In order to adjust
hi, jet hole middle part is bar shaped, and two sides are semicircle, and strip width is identical as comparison bore dia, and two sides are radius and comparison hole
The identical semicircle of radius；Water level regulation hole is located at water storage tank bottom.Comparison hole, the mould are provided on height adjustment fluidics module
Block external shape fits height adjustment fluidics module is adapted to slot.Damper modules include front apron, side baffle, pedestal, fluerics, water level
Adjust matching hole, lateral graduated scale, longitudinal graduated scale, the second cooperation slot；It is described for the ease of the disassembly of water level regulation hole
Water level regulation matching hole longitudinal aperture is greater than water level regulation hole aperture.The comparison hole and jet stream hole number is i.
Preferably, saving space, the first cooperation slot and the second cooperation slot adaption section are circle for the ease of disassembly
Shape.
Preferably, height adjustment fluidics module shape is step type, slot adaptation is adapted to height adjustment fluidics module
Part is the rectangle of ladder protrusion, and height adjustment fluidics module adaptation slot and the rectangle of the ladder protrusion are suitable in water storage module
With fixation.
Preferably, the comparison hole and jet stream hole number i preferably three.
Preferably, the making material of water storage module, height adjustment fluidics module, damper modules is organic transparent glass,
Low cost and convenient for observation.
Preferably, the preferred water of liquid.
The working method of bernoulli principle demonstration instrument for teaching disclosed by the invention are as follows: filled in the water storage tank of water storage module just
Begin the liquid that height is H, adjusts the initial water level in water storage tank by the water level regulation hole in water storage module to adjust water-head
H-hi, initial time height adjustment fluidics module be located at height adjustment fluidics module adaptation slot bottom, comparison hole and height adjust
Save fluidics module adaptation slot wall surface contact, the comparison hole and non-connection of jet hole, thus compare hole not with water storage inside modules
Fluid communication avoids generating liquid jet under original state.When carrying out bernoulli principle teaching demonstration, by height adjustment jet stream mould
Block pushes up, comparison hole and jet hole connection, and then compares hole and water storage tank internal flow connection, generates jet stream.By right
Height h is adjusted than the contact position of hole and jet holei, wherein i is the quantity for comparing hole, and then adjusts water-head H-hi, different
Water-head H-hiThe liquid with different initial kinetic energies can be projected, the difference of liquid injection distance S is caused.According to Bernoulli equation
And Newton's second law, compare hole hiPlace and column Bernoulli equation at free surface H, obtain following equation group:
hiThe height in respectively i-th comparison hole, hiAdjustable range according to specific bernoulli principle teaching demonstration test survey
?.Fluid column distance of fall at i-th of comparison hole is approximately equal to i-th of comparison hole height hi, compare hole height hiPass through longitudinal quarter
Degree ruler measures.
According to equation group (1), the spray distance S and water level H for further deriving liquid in fluerics have following relationship:
When bernoulli principle teaching demonstration is tested, it is each to measure by longitudinal graduated scale that the parameter measured is actually needed
Compare hole height hiAnd the actual ejection distance S ' in each comparison hole measured by lateral graduated scalei.It is obtained by comparing calculation
S outiWith the actual ejection distance S ' in actually measured each comparison holeiVerify bernoulli principle.Bernoulli principle teaching is completed to drill
Show experiment.
When needing to stop lecture experiment, height adjustment fluidics module is reinserted to height adjustment fluidics module and is adapted to
Slot bottom, the connection between jet hole and comparison hole are cut off, and jet stream stops, and dismantle water storage module, gear respectively as needed
Plate module, height adjustment fluidics module complete teaching demonstration.
The utility model has the advantages that
1, the bernoulli principle demonstration instrument for teaching that there is no in the prior art, bernoulli principle teaching demonstration disclosed by the invention
Instrument, provides a kind of more intuitive bernoulli principle demonstration teaching aid, and the teaching aid passes through adjustable, observable water-head H-hi,
Theoretical stream distance S, and the practical stream distance S ' verifying primary tested by the teaching aid are sought obtaining using bernoulli principle
Exert sharp principle.Bernoulli principle demonstration instrument for teaching disclosed by the invention can be carried out on classroom bernoulli principle theory with
The sync instruction of experimental applications makes student have understanding more profound to this learning Content.
2, bernoulli principle demonstration instrument for teaching disclosed by the invention, water storage module, damper modules, height adjustment fluidics module
Detachably, small in size, light-weight, convenient for users to carry.
3, bernoulli principle demonstration instrument for teaching disclosed by the invention can prevent liquid splash by the way that baffle is arranged, keep
The neat and tidy of teaching environment.
4, bernoulli principle demonstration instrument for teaching disclosed by the invention, teaching aid integral manufacturing material are organic transparent glass, are made
Valence is cheap and convenient for observation.
Detailed description of the invention
Fig. 1 is the overall top view of bernoulli principle demonstration instrument for teaching disclosed by the invention；
Fig. 2 is overall structure cross-sectional view under working condition of the present invention；
Fig. 3 is water storage module diagram；
Fig. 4 is height adjustment fluidics module schematic diagram
Fig. 5 is damper modules schematic diagram.
Fig. 6 is comparison hole and jet hole junction partial sectional view
Wherein, 1- water storage module, 2- height adjustment fluidics module, 3- damper modules.
For water storage module, 1.1- water storage tank, 1.2- jet hole, 1.3- water level regulation hole, 1.4- first cooperate slot,
1.5- height adjustment fluidics module is adapted to slot.
For height adjustment fluidics module, 2.1- compares hole.
To with damper modules, 3.1- front apron, 3.2- side baffle, 3.3- pedestal, the fluerics 3.4-, 3.5- water level regulation are matched
Close hole, 3.6- transverse direction graduated scale, the longitudinal direction 3.7- graduated scale, the cooperation slot of 3.8- second.
Specific embodiment
The present invention will now be described in detail with reference to the accompanying drawings and examples.
Embodiment 1
As shown in attached drawing 1,2, a kind of height adjustment bernoulli principle demonstrator disclosed in the present embodiment, including water storage module
1, height adjustment fluidics module 2, damper modules 3.
1.1 slot inner height of water storage tank is 200mm, and water storage module 1 and height adjustment fluidics module 2 are respectively equipped with jet hole
1.2 with comparison hole 2.1, there are three jet holes 1.2, and the adjustable range of three jet holes 1.2 is 31mm, each jet hole 1.2
It is spaced 32mm, is evenly distributed on height adjustment fluidics module cooperation 1.5 inner wall of slot.Lateral graduated scale 3.6 measures the upper limit
205mm, the measurement upper limit of longitudinal graduated scale 3.7 are 200mm.
Height adjustment fluidics module 2 is located at height adjustment fluidics module adaptation 1.5 bottom of slot under instrument original state, right
It is contacted than hole 2.1 with height adjustment fluidics module adaptation 1.5 wall surface of slot, comparison hole 2.1 and the non-connection of jet hole 1.2, in turn
Hole 2.1 is compared not with 1 internal flow connection of water storage module, avoids generating liquid jet under original state.When instrument works, storage
Water is filled in sink 1.1, adjusting initial water level height by water level regulation hole 1.3 is H=180mm, and the numerical value is by longitudinally carving
Anale settting scale measurement obtains.Height adjustment fluidics module 2 is pushed up, the height in three comparison holes 2.1 is through longitudinal graduated scale
3.7 measurements are respectively as follows: h1=40mm, h2=100mm, h3=160mm.It is connected simultaneously with jet hole 1.2.At this point, the height of connection position
Degree difference is respectively as follows:
H-h1=140mm
H-h2=80mm
H-h3=20mm
According to bernoulli principle, the theoretical spray distance of three jet holes 1.2 should be respectively as follows:
The actual ejection distance that jet stream is generated at comparison hole 2.1 is measured through lateral graduated scale 3.6 are as follows:
Actual ejection distance is close with theoretical spray distance, i.e. verifying bernoulli principle.
When needing to stop using, height adjustment fluidics module 2 is reinserted to height adjustment fluidics module to cooperate and is inserted
The connection of 1.5 bottom of slot, jet hole 1.2 and comparison hole 2.1 is cut off, and jet stream stops.
Above-described specific descriptions have carried out further specifically the purpose of invention, technical scheme and beneficial effects
It is bright, it should be understood that the above is only a specific embodiment of the present invention, the protection model being not intended to limit the present invention
It encloses, all within the spirits and principles of the present invention, any modification, equivalent substitution, improvement and etc. done should be included in the present invention
Protection scope within.
Claims (7)
1. bernoulli principle demonstration instrument for teaching, it is characterised in that: including water storage module (1), height adjustment fluidics module (2), gear
Plate module (3)；Three modules use Modularized dismounting structure；The water storage module (1) includes, water storage tank (1.1), jet stream
Hole (1.2), water level regulation hole (1.3), the first cooperation slot (1.4), height adjustment fluidics module adaptation slot (1.5)；First
Cooperation slot (1.4) is adapted to the second cooperation slot (3.8)；It is bar shaped in the middle part of jet hole (1.2), two sides are to adjust hi
Semicircle, strip width is identical as comparison hole (2.1) diameter, and two sides are radius semicircle identical with comparison hole (2.1) radius；
Water level regulation hole (1.3) is located at water storage tank (1.1) bottom；Comparison hole (2.1) is provided on height adjustment fluidics module (2), it should
Module external shape fits height adjustment fluidics module is adapted to slot (1.5)；Damper modules (3) include front apron (3.1), side baffle
(3.2), pedestal (3.3), fluerics (3.4), water level regulation matching hole (3.5), lateral graduated scale (3.6), longitudinal graduated scale
Ruler (3.7), the second cooperation slot (3.8)；For the ease of water level regulation hole (1.3) disassembly, the water level regulation matching hole (3.5)
Longitudinal aperture is greater than water level regulation hole (1.3) aperture；The comparison hole (2.1) and jet hole (1.2) quantity is i.
2. bernoulli principle demonstration instrument for teaching as described in claim 1, it is characterised in that: for the ease of disassembly, space is saved,
First cooperation slot (1.4) is circle with the second cooperation slot (3.8) adaption section.
3. bernoulli principle demonstration instrument for teaching as described in claim 1, it is characterised in that: height adjustment fluidics module (2) is outside
Shape is step type, and the rectangle that slot (1.5) adaption section is ladder protrusion, water storage module are adapted to height adjustment fluidics module
(1) height adjustment fluidics module adaptation slot (1.5) and the rectangular adapter of the ladder protrusion are fixed in.
4. bernoulli principle demonstration instrument for teaching as described in claim 1, it is characterised in that: the comparison hole (2.1) and penetrate
Discharge orifice (1.2) quantity i selects three.
5. bernoulli principle demonstration instrument for teaching as described in claim 1, it is characterised in that: water storage module (1), height adjustment are penetrated
Flow module (2), damper modules (3) making material be organic transparent glass.
6. bernoulli principle demonstration instrument for teaching as described in claim 1, it is characterised in that: liquid selects water.
7. the bernoulli principle demonstration instrument for teaching as described in claim 1,2,3,4,5 or 6, it is characterised in that: working method is,
The liquid that elemental height is H is filled in the water storage tank (1.1) of water storage module (1), passes through the water level regulation hole on water storage module (1)
(1.3) initial water level in water storage tank (1.1) is adjusted to adjust water-head H-hi, initial time height adjustment fluidics module (2)
It is adapted to slot (1.5) bottom positioned at height adjustment fluidics module, hole (2.1) is compared with height adjustment fluidics module and is adapted to slot
(1.5) wall surface contacts, comparison hole (2.1) and jet hole (1.2) non-connection, so compare hole (2.1) not with water storage module (1)
Internal flow connection avoids generating liquid jet under original state；When carrying out bernoulli principle teaching demonstration, height adjustment is penetrated
Flow module (2) pushes up, comparison hole (2.1) and jet hole (1.2) connection, and then compares in hole (2.1) and water storage tank (1.1)
Portion's fluid communication generates jet stream；Height hi is adjusted by comparison hole (2.1) and jet hole (1.2) contact position, wherein i is pair
Than the quantity of hole (2.1), and then adjust water-head H-hi, different water-head H-hiThe liquid with different initial kinetic energies can be projected
Body leads to the difference of liquid injection distance S；According to Bernoulli equation and Newton's second law, hole (2.1) h is comparediLocate and oneself
By liquid level H column Bernoulli equation, following equation group is obtained:
hiThe height of respectively i-th comparison hole (2.1), hiAdjustable range tested according to specific bernoulli principle teaching demonstration
It measures；Fluid column distance of fall is approximately equal to i-th of comparison hole (2.1) height h at i-th of comparison hole (2.1)i, compare hole (2.1)
Height hiIt is measured by longitudinal graduated scale；
According to equation group (1), the spray distance S and water level H for further deriving liquid in fluerics (3.4) have following relationship:
When bernoulli principle teaching demonstration is tested, the parameter measured is actually needed and is measured by longitudinal graduated scale (3.7)
Each comparison hole (2.1) height hiAnd the actual ejection distance of each comparison hole (2.1) measured by lateral graduated scale (3.6)
S′i；The S obtained by comparing calculationiWith the actual ejection distance S ' of actually measured each comparison hole (2.1)iIt is former to verify Bernoulli Jacob
Reason；Complete the experiment of bernoulli principle teaching demonstration；
When needing to stop lecture experiment, height adjustment fluidics module (2) is reinserted to height adjustment fluidics module and is adapted to
Slot bottom, the connection between jet hole (1.2) and comparison hole (2.1) are cut off, and jet stream stops, as needed disassembly storage respectively
Water module (1), damper modules (3), height adjustment fluidics module (2) complete teaching demonstration.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811617108.XA CN109448514B (en) | 2018-12-28 | 2018-12-28 | Bernoulli principle teaching demonstration instrument |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811617108.XA CN109448514B (en) | 2018-12-28 | 2018-12-28 | Bernoulli principle teaching demonstration instrument |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109448514A true CN109448514A (en) | 2019-03-08 |
| CN109448514B CN109448514B (en) | 2020-11-03 |
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ID=65538446
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811617108.XA Expired - Fee Related CN109448514B (en) | 2018-12-28 | 2018-12-28 | Bernoulli principle teaching demonstration instrument |
Country Status (1)
| Country | Link |
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| CN (1) | CN109448514B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU628530A1 (en) * | 1977-05-23 | 1978-10-15 | Университет Дружбы Народов Имени Патриса Лумумбы | Educational appliance on hydraulic |
| CN101882391A (en) * | 2009-05-08 | 2010-11-10 | 河南农业大学 | Authentication instrument of Bernoulli equation |
| RU2473388C1 (en) * | 2011-07-25 | 2013-01-27 | Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Ярославский государственный технический университет" | Lab module |
| CN104282203A (en) * | 2014-09-27 | 2015-01-14 | 复旦大学 | Bernoulli equation demonstration instrument |
| CN204480554U (en) * | 2015-01-26 | 2015-07-15 | 上海市宝山区青少年科学技术指导站 | Bernoulli's theorem apparatus for demonstrating |
| CN205827740U (en) * | 2016-04-21 | 2016-12-21 | 西安建筑科技大学 | A kind of viscosity pipe flow synthetic instruction experiment instrument |
| CN206162956U (en) * | 2016-08-08 | 2017-05-10 | 祝庆龙 | Bernoulli's principle experimental apparatus |
-
2018
- 2018-12-28 CN CN201811617108.XA patent/CN109448514B/en not_active Expired - Fee Related
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU628530A1 (en) * | 1977-05-23 | 1978-10-15 | Университет Дружбы Народов Имени Патриса Лумумбы | Educational appliance on hydraulic |
| CN101882391A (en) * | 2009-05-08 | 2010-11-10 | 河南农业大学 | Authentication instrument of Bernoulli equation |
| RU2473388C1 (en) * | 2011-07-25 | 2013-01-27 | Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Ярославский государственный технический университет" | Lab module |
| CN104282203A (en) * | 2014-09-27 | 2015-01-14 | 复旦大学 | Bernoulli equation demonstration instrument |
| CN204480554U (en) * | 2015-01-26 | 2015-07-15 | 上海市宝山区青少年科学技术指导站 | Bernoulli's theorem apparatus for demonstrating |
| CN205827740U (en) * | 2016-04-21 | 2016-12-21 | 西安建筑科技大学 | A kind of viscosity pipe flow synthetic instruction experiment instrument |
| CN206162956U (en) * | 2016-08-08 | 2017-05-10 | 祝庆龙 | Bernoulli's principle experimental apparatus |
Non-Patent Citations (3)
| Title |
|---|
| 于海清: "《小型伯努利方程验证实验装置》", 《吉林工业大学学报》 * |
| 吴亚东等: "《Heron喷泉水柱高度模型及试验验证》", 《唐山师范学院学报》 * |
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| CN109448514B (en) | 2020-11-03 |
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Granted publication date: 20201103 |