CN206058736U - Water particle tracer in a kind of flume experiment - Google Patents

Water particle tracer in a kind of flume experiment Download PDF

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Publication number
CN206058736U
CN206058736U CN201620549743.9U CN201620549743U CN206058736U CN 206058736 U CN206058736 U CN 206058736U CN 201620549743 U CN201620549743 U CN 201620549743U CN 206058736 U CN206058736 U CN 206058736U
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China
Prior art keywords
cross bar
water
connecting rope
support
water particle
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Expired - Fee Related
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CN201620549743.9U
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Chinese (zh)
Inventor
刘亚伊
陶爱峰
苏俊玮
蔡颖
王懿
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Hohai University HHU
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Hohai University HHU
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Abstract

This utility model belongs to experimental provision field, water particle tracer in specially a kind of flume experiment, including support, cross bar and spike part;The support is installed on tank;The cross bar is installed on support and can slide along the length direction on the long side of support;The trace particle that the spike part includes connecting rope and is fixed in connecting rope;The connecting rope is installed on cross bar and can move along the length direction of cross bar.This utility model simple structure, easy to operate, flexible and convenient to use, low cost and spike is functional, can directly in observation water slot wave flow field arbitrary water particle movement locus.

Description

Water particle tracer in a kind of flume experiment
Technical field
This utility model belongs to experimental provision field, water particle tracer in specially a kind of flume experiment.
Background technology
There are some researches show, when wave is impacted to object, the impulsive force for producing maximum injury is not that surface is advanced Velocity of wave but be current speed by the speed of water particle inside wave, even if disaster-stricken body vulnerability very little, it is also difficult to avoid wave Wave disaster caused by internal water particle.Not only in wave field, the movement locus of the water particle in true wave current field are also It is the function of particle original coordinates, time, wave height, wavelength and the depth of water, but also virgin flow flow velocity and its distribution will be subject to special The impact of property.Tracer study to the actual water quality locus of points, also carries out seldom due to lacking necessary laboratory facilities so far.
Water particle spike refers to using the tracer of artificial manufacture substitute water particle, by fortune of the water particle in wave current field Dynamic rail mark shows and can use the instruments such as video camera to shoot record.Water particle spike is not only inquires into water particle in wave current field The key of kinetic characteristic, and the teaching demonstration of relevant wave theory course is can be applicable to, excite the learning enthusiasm of students.
PIV flow velocity measuring systems being adopted the current spike means to water particle motion track, although PIV flow-speed measurements system more System is with higher degree of accuracy, but PIV complete equipments are prohibitively expensive, and shooting result is not directly perceived, and post-processing steps are numerous and diverse, no Directly can show.Another kind of more conventional tracing method is that the solid float being directly close to water using density makees spike Agent, but Technology at this stage is confined to, in experimentation, water temperature will be affected and be changed by temperature or water pump etc., water capacity weight Accordingly change, the proportion of solid float can not possibly accomplish completely the same with water proportion, float sheet has one in hydrostatic Fixed heavy speed or floating speed.Although also someone studies the motion of water particle using liquid tracer, compensate for a certain extent solid Some defects of body float, but liquid tracer has the shortcomings that easily diffusion, when water particle motion is more violent, and follows the trail of the time Easily fail when longer.
Utility model content
This utility model provides a kind of simple structure, easy to operate, flexible and convenient to use, low cost and spike is functional Flume experiment in water particle tracer, which can direct arbitrary water particle motion track in observation water slot wave flow field.
To realize above-mentioned technical purpose, the specific technological means that this utility model is taken are:Water in a kind of flume experiment Particle tracer device, including support, cross bar and spike part;The support is installed on tank;The cross bar is installed on and props up On frame and can along the long side of support length direction slide;The spike part includes connecting rope and showing of being fixed in connecting rope Track particle;The connecting rope is installed on cross bar and can move along the length direction of cross bar.
Used as the improved technical scheme of this utility model, the support includes two stocks be arrangeding in parallel, flat at two The side that the stock of row setting is opposite is provided with the chute moved in parallel for cross bar;The cross bar is provided with connecting portion at two ends, connection The size in portion is matched with the size of chute, and cross bar is installed in chute by connecting portion.
Used as the improved technical scheme of this utility model, the stock indicates scale.
Used as the improved technical scheme of this utility model, the stock bottom surface is provided with mounting groove, and support is pacified by mounting groove Loaded on tank.
Used as the improved technical scheme of this utility model, the connecting rope is installed on cross bar by pipe crimping;The cross bar In the direction perpendicular to cross bar upper surface, rectangular through-hole groove is set;The pipe crimping is installed on cross bar by rectangular through-hole groove, and And pipe crimping can pass through rectangular through-hole groove and move along the length direction of cross bar.
Used as the improved technical scheme of this utility model, the pipe crimping carries external screw thread, and pipe crimping passes through nut-washer combination It is installed on cross bar.
Used as the improved technical scheme of this utility model, the upper surface of the cross bar indicates scale.
Used as the improved technical scheme of this utility model, the connecting rope is the rope that can be absorbed water, and the density of connecting rope compared with The density of water is little.
Beneficial effect
Trace particle connecting rope is concatenated by the device, connecting rope is wound on pipe crimping, and pipe crimping is rack-mount to be made to show Track particle is in suspended state, trace particle is appointed in wave current field by the length of the position and connecting rope that adjust pipe crimping One position;In addition, fixing trace particle by connecting rope so that trace particle will not be because of the difference with water body density in weight The downward problem made a concerted effort, effectively improve trace particle sedimentation diffusion in prior art is produced under power and buoyancy.Should Installation cost is less than 800 yuan, and PIV tracers price of the prior art up to more than 800,000, significantly reduce making Cost, and spike is functional, can be used for relevant wave class demonstration and the experiment higher to required precision.
Description of the drawings
The front view of water particle tracer in a kind of Fig. 1 flume experiments of the present utility model;
The side view of water particle tracer in a kind of Fig. 2 flume experiments of the present utility model;
The top view of water particle tracer in a kind of Fig. 3 flume experiments of the present utility model;
In a kind of Fig. 4 flume experiments of the present utility model in water particle tracer stock end view;
In a kind of Fig. 5 flume experiments of the present utility model in water particle tracer cross bar front view;
In a kind of Fig. 6 flume experiments of the present utility model in water particle tracer cross bar top view;
Pipe crimping schematic diagram in water particle tracer in a kind of Fig. 7 flume experiments of the present utility model;
Spike grain in a kind of flume experiment in Fig. 8 embodiments 1 in water particle tracer experimentation in 0m depths Sub-trajectory figure;
Showing in 0.132m depths in water particle tracer experimentation in a kind of flume experiment in Fig. 9 embodiments 1 Track particle trajectory figure;
In 0.266m depths in water particle tracer experimentation in a kind of flume experiment in Figure 10 embodiments 1 Trace particle trajectory diagram;
In 0.356m depths in water particle tracer experimentation in a kind of flume experiment in Figure 11 embodiments 1 Trace particle trajectory diagram;
In 0.527m depths in water particle tracer experimentation in a kind of flume experiment in Figure 12 embodiments 1 Trace particle trajectory diagram;
Showing in 0.66m depths in water particle tracer experimentation in a kind of flume experiment in Figure 13 embodiments 1 Track particle trajectory figure;
In a kind of flume experiment in Figure 14 embodiments 1 in water particle tracer experimentation trace particle in depth Trace particle composite trochoid figure at 0m, 0.132m, 0.266m, 0.356m, 0.527m and 0.66m;
In figure, 1, pipe crimping;2nd, support;3rd, stock;4th, quarter butt;5th, cross bar;6th, trace particle;7th, connecting rope;8th, spike portion Part;9th, chute;10th, mounting groove;11st, rectangular through-hole groove;12nd, connecting portion.
Specific embodiment
To make the purpose and technical scheme of this utility model embodiment clearer, implement below in conjunction with this utility model The accompanying drawing of example, is clearly and completely described to the technical scheme of this utility model embodiment.Obviously, described embodiment It is a part of embodiment of the present utility model, rather than the embodiment of whole.Based on described embodiment of the present utility model, The every other embodiment obtained on the premise of without the need for creative work by those of ordinary skill in the art, belongs to practical Novel protected scope.
Those skilled in the art of the present technique are appreciated that unless otherwise defined, all terms used herein(Including technology art Language and scientific terminology)With with this utility model art in those of ordinary skill general understanding identical meaning.Also It should be understood that those terms defined in such as general dictionary are should be understood that with the context with prior art The consistent meaning of meaning, and unless defined as here, will not be explained with idealization or excessively formal implication.
The implication of " long and short " described in this utility model refers to relative to equipment the both sides for itself referring to support Size, longer side is stock, and shorter side is quarter butt, rather than the specific restriction to equipment mechanism of the present utility model.
It can also be between part that the implication of " connection " described in this utility model can be being directly connected between part Being indirectly connected with by other parts.
Embodiment
Water particle tracer in a kind of flume experiment, including support 2, cross bar 5, and spike part 8;The support 2 It is installed on tank, and the size of support 2 is arranged according to the size of tank;The cross bar 5 be installed on support 2 and can along The length direction on 2 long side of frame slides;The trace particle 6 that the spike part 8 includes connecting rope 7 and is fixed in connecting rope 7; The connecting rope 7 is installed on cross bar 5 and can move along the length direction of cross bar 5.The length direction of cross bar 5 refers to whole cross bar A 5 overall most long directions.
In the present embodiment, the support 2 includes two stocks 3 be arrangeding in parallel and is individually fixed in 3 two ends of stock Two quarter butts 4;Stock 3 is provided with mounting groove 10 in bottom surface, and the size of mounting groove 10 is matched with the marginal dimension of tank, and support 2 leads to Cross mounting groove 10 to be installed on tank;Two stocks 3 be arrangeding in parallel are provided with the cunning moved in parallel for cross bar 5 in opposite side Groove 9;The cross bar 5 is provided with connecting portion 12 at two ends, and the size of connecting portion 12 is matched with the size of chute 9, and cross bar 5 is by connection Portion 12 is installed in chute 9;The cross bar 5 arranges rectangular through-hole groove 11, the rectangle in the direction perpendicular to 5 upper surface of cross bar Through-hole groove 11 only has four side walls, and without diapire, the space surrounded by four side walls ensure that pipe crimping 1 can pass through rectangular through-hole Groove 11 length direction that can be along space in cross bar 5 is reciprocated;The connecting rope 7 is installed on cross bar 5 by pipe crimping 1, The pipe crimping 1 carries external screw thread, and pipe crimping 1 is same with lower section by the top of cross bar 5 is located in pipe crimping 1 through after rectangular through-hole groove 11 When nut-washer combination is installed, realization is held on pipe crimping 1 on cross bar 5, and passes through tightening nut washer sets after installation Mobile pipe crimping 1 is closed, pipe crimping 1 is moved along 5 length direction of cross bar, specifically by the elastic of two nut-washer combinations of regulation Degree further enables pipe crimping 1 movable, then needs to adjust position of the pipe crimping 1 on cross bar 5 according to experiment;
In order that adjustment trace particle 6 position in the sink is convenient, stock 3,5 upper surface of cross bar and connection Rope 7 indicates scale.
In order that the minimum connecting rope 7 of impact that connecting rope 7 is moved to wave current field is the rope that can be absorbed water, and connecting rope 7 density is little compared with the density of water.And the diameter of connecting rope 7 is less than the diameter of trace particle 6.
Another object of the present utility model is the using method for providing water particle tracer in a kind of flume experiment, is wrapped Include following steps:The size of tank, the element of wave of calibration wave current field and flow rate of water flow in A, surveying laboratory, and according to gained Data determine the installation position of the size of support 2 and trace particle 6;B, according to experiment needs, adjust cross bar 5 on support 2 The length of the position of position, pipe crimping 1 on cross bar 5 and connecting rope 7 determines the locus of trace particle 6;C, unlatching water quality Point tracer shoots experimentation using video camera, and will test video conversion into photo-frame, in every photograph frame obtains right The coordinate of moment trace particle 6 is answered, gained number of coordinates strong point is sequentially connected the movement locus for depicting trace particle 6.
The flume experiment device instrument and structure chi of the water particle spike suspended based on trace particle 6 in the present embodiment It is very little:
1. tank length × width × height=60m × 1m × 1.5m;
2. spike part 8 by six density 1.03g/cm3, diameter 2mm spherical ABS plastic granule trace particle 6 in 3m Rearrange in the long connecting rope 7 for absorbing water, during resting state, connecting rope 7 be in tank middle position, with two side walls away from From being 0.5m;
3. pipe crimping 1 is made up of away from the cylindrical thread steel pipe for 1.0mm height × diameter=0.20m × 0.05m, tooth, and pipe crimping 1 leads to Cross nut-washer combination to be fixed on cross bar 5, and pipe crimping 1 can be used as adjusting in the part for stretching out top nut-washer combination The rotation handle of 7 length of whole connecting rope.
Support 2 is prepared from by stainless steel material, forms " class mouth " shape support 2, and its 2 stock of medium-height trestle, 3 size is:Long × Width × height=1.5m × 0.2m × 0.14m, the size of 3 upper hopper chute 9 of stock is:Length × width × height=1.1m × 0.03m × 0.02m; On 2 stock 3 of support, the size of mounting groove 10 is:Length × width × height=1.5m × 0.1m × 0.04m;2 quarter butt of support, 4 size is:It is long × wide × height=0.8m × 0.1m × 0.14m, in order to ensure that the steadiness of support 2 is provided with framework in the periphery of support 2;Cross bar 5 Size is:Length × width × height=0.8m × 0.1m × 0.14m;The size of 5 connecting portion 12 of cross bar:Length × width × height=0.03m × 0.1m × 0.02m, on cross bar 5, the size of rectangular through-hole groove 11 is length × wide=0.8m × 0.06m.
Filming apparatus main body is Canon 5DMaxlll and supporting spider, and spider center is fixed on trace particle 6 and connects Restrict at 7 dead ahead 1.5m.
The course of work of this utility model device is as follows:
1. according to groove depth of water 0.66m of shown in Fig. 1, fetching water, calibration is carried out to wave, rule enters under conditions of embodiment 1 Jetting ripple wave height is 0.10m, and the cycle of incidence wave, wave caused trace particle 6 to transport after spike part 8 from 1.20 seconds It is dynamic.
First, at scope support 2 being fixed on needed for experiment, spike part 8 is generally moved to need observation position, then Position adjustment spike part 8 by cross bar 5 on stock 3 is in the position of X-direction;Then pass through position of the pipe crimping 1 on cross bar 5 Put the position in the Y direction of adjustment spike part 8;The length that pipe crimping 1 adjusts connecting rope 7 is finally rotated, makes six trace particles 6 equal Positioned at observation water particle position needed for wave current field.
The movement locus of trace particle 6 are shot using video camera.
Such as need to study track of the different elements of wave to water particle motion, then only need to change wave in said process 1 will Plain initial condition, is then tested further according to said process 2~3.
Measured test data is analyzed, result such as Fig. 8, trace particle 6 depth of 6 depth of trace particle for 0m It is 0.356m for result such as Fig. 9 of 0.132m, result such as Figure 10,6 depth of trace particle that 6 depth of trace particle is 0.266m As a result if Figure 11,6 depth of trace particle are result such as Figure 12, the result such as figure that 6 depth of trace particle is 0.66m of 0.527m 13.Fitting track of the trace particle 6 at six different depths is as shown in figure 14 in the result of the same coordinate system.
Significantly closed as can be seen that surveying 6 track of trace particle and presenting by Fig. 8, Fig. 9, Figure 10, Figure 11 and Figure 12 It is oval;At the bottom, trace particle 6 only swings along long axis direction as shown in Figure 13;As seen from Figure 14, in identical wave Under key element, the water quality locus of points at different depth diminishes with the increase of depth, and major and minor axis difference increases with depth and increases, Meet the rule of Wave Theory.
Understand that the fitting track of data point and theoretical water particle trajectory error are less than 1% by the error analyses in table 1, Precision is very high, illustrates that the spike of tracer is functional.In table 1, a actually refers to the length half of trace particle fitting track Axle;A theories refer to the major semiaxis of the water quality locus of points calculated according to Wave Theory;In table, "-" is represented under water, for example "- 0.266m " represents depth under water as 0.266m.
Result and the error amount of actual result that 1 trace particle of table is measured under different depth
Trace particle depth Error=(Actual-a of a are theoretical)/ a is theoretical
z=-0m 0.3685%
z=-0.132m 0.1279%
z=-0.266m 0.2348%
z=-0.356m 0.2440%
z=-0.527m 0.6986%
z=-0.66m 0.1324%
Mean error 0.3014%
Principle:Existing spike means are confined to directly trace particle 6 be put in water, and density and the water of trace particle 6 must So have differences, buoyancy is unable to complete equipilibrium with gravity, and trace particle 6 can produce the elevating movement of itself under force action, The water particle in naturalness can not be equally substituted, the intuitive of trace particle 6 is also not good enough.This utility model passes through spike The slightly larger trace particle 6 of the concatenation density ratio water of 6 connecting rope of particle 7 is simultaneously connected with movable supporting frame 2 so that at trace particle 6 In " suspended state ", water particle that can be in equivalent substitution passive wave flow field, in order to reduce connecting rope 7 to trace particle 6 in fortune Vertical effect of contraction in dynamic wave current field, the light cord that 7 selection of connecting rope can absorb water simultaneously leave enough having more than needed in bottom of gullet Length.
The negligible cord of autologous density that 6 connecting rope of trace particle, 7 employing can absorb water, connecting rope 7 are close after absorbing water Degree is close to water, can approximate substitution position water body, impact is produced on the motion of wave current field hardly.
Embodiment of the present utility model is these are only, its description is more concrete and detailed, but therefore can not be understood It is the restriction to this utility model the scope of the claims.It should be pointed out that for the person of ordinary skill of the art, do not taking off On the premise of conceiving from this utility model, some deformations and improvement can also be made, these belong to protection of the present utility model Scope.

Claims (8)

1. water particle tracer in a kind of flume experiment, it is characterised in that including support, cross bar and spike part;It is described Support is installed on tank;The cross bar is installed on support and can slide along the length direction on the long side of support;The spike portion Part includes connecting rope and the trace particle being fixed in connecting rope;The connecting rope is installed on cross bar and can be along the length of cross bar The movement of degree direction.
2. water particle tracer in a kind of flume experiment according to claim 1, it is characterised in that the support includes Two stocks be arrangeding in parallel, are provided with the chute moved in parallel for cross bar two opposite sides of the stock be arrangeding in parallel;Institute Stating cross bar and connecting portion being provided with two ends, the size of connecting portion is matched with the size of chute, and cross bar is installed on chute by connecting portion In.
3. water particle tracer in a kind of flume experiment according to claim 2, it is characterised in that the stock is indicated Scale.
4. water particle tracer in a kind of flume experiment according to claim 2, it is characterised in that the stock bottom surface Mounting groove is provided with, support is installed on tank by mounting groove.
5. water particle tracer in a kind of flume experiment according to claim 1, it is characterised in that the connecting rope is led to Cross pipe crimping to be installed on cross bar;The cross bar arranges rectangular through-hole groove in the direction perpendicular to cross bar upper surface;The pipe crimping leads to Cross rectangular through-hole groove to be installed on cross bar, and pipe crimping can pass through rectangular through-hole groove and move along the length direction of cross bar.
6. water particle tracer in a kind of flume experiment according to claim 5, it is characterised in that the pipe crimping is carried External screw thread, pipe crimping are installed on cross bar by nut-washer combination.
7. water particle tracer in a kind of flume experiment according to claim 1, it is characterised in that the cross bar it is upper Surface indicates scale.
8. water particle tracer in a kind of flume experiment according to claim 1, it is characterised in that the connecting rope is The rope that can be absorbed water, and the density of connecting rope is little compared with the density of water.
CN201620549743.9U 2016-06-08 2016-06-08 Water particle tracer in a kind of flume experiment Expired - Fee Related CN206058736U (en)

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CN201620549743.9U CN206058736U (en) 2016-06-08 2016-06-08 Water particle tracer in a kind of flume experiment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201620549743.9U CN206058736U (en) 2016-06-08 2016-06-08 Water particle tracer in a kind of flume experiment

Publications (1)

Publication Number Publication Date
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105894938A (en) * 2016-06-08 2016-08-24 河海大学 Waterparticle tracing device in water tank experiment and use method of waterparticle tracing device
CN109238646A (en) * 2018-10-23 2019-01-18 汤十力 Method and apparatus according to suspension ball motion morphology tracing and positioning leakage passage entrance

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105894938A (en) * 2016-06-08 2016-08-24 河海大学 Waterparticle tracing device in water tank experiment and use method of waterparticle tracing device
CN105894938B (en) * 2016-06-08 2018-11-27 河海大学 Water particle tracer and its application method in a kind of flume experiment
CN109238646A (en) * 2018-10-23 2019-01-18 汤十力 Method and apparatus according to suspension ball motion morphology tracing and positioning leakage passage entrance

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Granted publication date: 20170329

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