CN103148891B - Method for monitoring windproof effect of windproof net in coal field area - Google Patents

Abstract

The invention discloses a method for monitoring a windproof effect of a windproof net in a coal field area. The method comprises detection of a windproof factor of the windproof net and detection of a dust reduction effect of the windproof net. The process of the detection of the windproof factor of the windproof net comprises the steps: selecting sixteen measurement points from the inside of the coal field area, selecting one referenced measurement point from the outside of the coal filed area, carrying out reasonable selection on the measurement points and the referenced measurement point, placing a measured datum into a formula to carry out calculation, and obtaining the windproof factor of the windproof net. The detection of the dust reduction effect of the windproof net comprises the steps: respectively selecting six sampling points from the inside and the outside of the coal field area, and estimating the dust reduction effect of the windproof net. The windproof factor and the dust reduction effect of the windproof net are obtained by measurement and calculation through the method, reference data can be supplied for arrangement of the windproof net in the coal field area, and quantification assessment on the dust suppression effect of the windproof net are convenient. A picture (a) is an arrangement diagram of wind speed measurement points of the windproof factor of the windproof net. A picture (b) is an arrangement diagram of dust concentration measurement points of the dust reduction effect of the windproof net.

Description

A kind of method of monitoring windproof effect of windproof net in coal field area

Technical field

The present invention relates to a kind of anti-wind net becalm the factor, subtract the monitoring method of dirt effect, especially a kind ofly to becalm the method for effect for calculating open coal on-site anti-wind net.

Background technology

Anti-wind net is the facility of the common windy weather conditions of improvement, and it is widely used because having advantages such as preventing snowfield drift, the soil erosion and Pollutants Diffusion, and current anti-wind net is widely used in coastal, arid and cold district.Such as, a large amount of bulk material (as coal dust and mineral powder) stores in large-scale open port district and transports, and these materials are exposed in wind, the erosion of wind-engaging, cause the loss of material and serious environmental problem.Spread in an atmosphere to reduce wind-blown dust's particle, one is suitable for the method reducing plant emissions and uses anti-wind net exactly.2009, establish large-scale anti-wind net in PORT OF QINHUANGDAO, Hebei province along coal yard---the fence engineering of Fia at present.

Use the great advantage of anti-wind net can reduce wind speed exactly in certain distance, the object of outdoor coal yard installation anti-wind net is the diffusion in order to prevent pollution caused by coal dust thing, but does not also have rational assessment data to the effect of becalming of anti-wind net at present.

Prior art awaits progressive and development further.

Summary of the invention

For solving the defect existed in prior art, the present invention proposes a kind of method of monitoring windproof effect of windproof net in coal field area, the anti-dust effect that the method is anti-wind net provides reference data.

Technical solution of the present invention is as follows:

Monitor a method for windproof effect of windproof net in coal field area, described method comprises the becalm mensuration of the factor and anti-wind net of anti-wind net and subtracts the mensuration of dirt effect, and the becalm mensuration of the factor of described anti-wind net comprises the following steps:

A, choose 16 measurement points at coal on-site, described measurement point is distributed with four rows and four columns at coal on-site, and each row is arranged every a dump buttress in the horizontal direction, and each row is arranged every a dump buttress in vertical direction.Interval arranges test, mainly get rid of adjacent coal stamp between mutually block on anti-wind net becalm effect measurement impact; And according to the measuring principle of cross sectional flow rate, described each measurement point is all chosen at the center of dump buttress upper surface, the measured value of central spot can be similar to the wind erosion situation characterizing whole coal and stamp upper surface, and remaining surface or side be all easily subject to coal stamp between mutually block and affect measurement result.Without any barrier place choose one outside coal yard district around, as wind speed with reference to measuring point, to represent the leeward wind speed feature of infinite point, described wind speed is arranged on the east side of eastern anti-wind net with reference to measuring point, and the horizontal range of itself and eastern anti-wind net is 25 times (i.e. 575m) of eastern anti-wind net net height, with 30 times (i.e. 690m) that the vertical range of southern anti-wind net is southern anti-wind net net height, this distance can ensure that the wind speed of reference point can not affect by covering of anti-wind net;

After b, step a complete, ZDR-1F wind speed and direction self-recording device is selected to measure.All wind speed and direction self-recording devices are measured simultaneously, wind speed and direction self-recording device is moving up and down measurement along the vertical direction of 16 measurement points chosen in step a and a reference point, and its vertical mobile height distance dump buttress ground must not more than 10m, wind direction and wind velocity registering instrument carries out one-shot measurement in every 10 seconds, records the measuring point air speed data x of every 10 seconds _irepresent, every 2 minutes records mean value is used represent, test duration every day is continuously monitoring in 24 hours, and during follow-on test, number is 5-7 days, selects sunnyly to carry out without rainy day gas;

The measurement point velocity standard deviation of c, calculating coal on-site, according to formula wherein: N is the measurement point air speed data number in 2 minutes; x _ifor the measurement point air speed data of every 10 seconds in step b; for the mean value of every 2 minutes records in step a;

D, the reference point velocity standard deviation calculated outside coal yard district, according to formula wherein: N is the reference point data amount check in 2 minutes; x _{i, ref}for the reference point air speed data of every 10 seconds; for the mean value of the reference point of every 2 minutes records;

E, according to formula calculate the factor of becalming when distance floor level is z rice, wherein:

R _{u, z}---the factor of becalming when distance floor level is z rice;

U (z)---the average velocity of measurement point when distance dump buttress ground vertical range is z rice, m/s;

σ (z)---measurement point velocity standard deviation when distance dump buttress ground vertical range is z rice;

U _ref---the average velocity of reference point, m/s;

σ _ref---the velocity standard deviation of reference point;

F, consider that annual natural wind is to continuous change, different wind vector, on the impact of the factor of becalming, proposes average of the whole year and to becalm the computing formula of the factor:

Wherein: ζ---annual is becalmed the factor;

F _i---the respective frequency distribution of annual 8 wind directions;

---in during monitoring, the mean value of the factor of becalming under each wind direction;

Coal dust contamination on the leeward, follow Gaussian distribution rule, concentration is along the center sending out dirt source, symmetrical on the leeward, and near stacking place, concentration is higher, away from when sending out dirt source, concentration sharply declines, heavily contaminated region is mainly in the centrical kilometer range in stockyard, accordingly, the mensuration that anti-wind net subtracts dirt effect comprises the following steps: with main anti-wind net---and eastern anti-wind net is benchmark, at coal on-site, 3 concentration sample points are set, it draws near apart from eastern anti-wind net and is respectively T1, T2, T3, according to T3 outside coal yard district, T2, T1 arranges 3 sampled point T4 from the corresponding distance of eastern anti-wind net, T5, T6, each sampled point is along the central axis of east side anti-wind net, arrange in straight line in the horizontal direction, wherein T4 sampled point and T3 sampled point distance anti-wind net are recently, and T6 sampled point and T1 sampled point distance anti-wind net are farthest, T4 sampled point and T3 sampled point, T5 sampled point and T2 sampled point, T1 sampled point and T6 sampled point between two to the east of anti-wind net be benchmark symmetrically relation, and sampled point T1, T2, T3 are that non-equidistant is successively decreased apart from the horizontal range of eastern anti-wind net, large discharge TSP air sampler is adopted to measure at each sampled point, all sampled points are 10m apart from the vertical range on ground, test duration every day is continuous sampling in 24 hours, and during follow-on test, number is 5-7 days, selects sunnyly to carry out without rainy day gas.

Described dump buttress is identical taper stacking, and the height of described anti-wind net is 23m, and the average height of dump is 6m.

Described anti-wind net factor of porosity is 0.4.

Described reference point T6 and sampled point T1 horizontal range are 800m.

The present invention proposes a kind of method predicting windproof effect of windproof net in coal field area, the method subtracts dirt effect to the Summing Factor of becalming of anti-wind net respectively and measures, becalm in the mensuration process of the factor at anti-wind net, carry out reasonably choosing to the position of measurement point and reference point, and measurement point is positioned at the upper surface center of dump buttress, the data recorded are substituted in formula and calculates, obtain the factor data of becalming of anti-wind net; Subtract in the mensuration process of dirt effect at anti-wind net, three sampled points are chosen at coal on-site, outside coal yard district, choose three sampled points, and outside coal yard district, point is farthest 400m apart from eastern anti-wind net, that can estimate anti-wind net in the radius of distance anti-wind net 500 meters subtracts dirt effect.The method measures, the anti-wind net that calculates becalms the factor and subtract dirt effect, can arrange the reference data that anti-wind net provides certain, be conducive to the quantitative evaluation of the effect of becalming to anti-wind net for coal field.

Accompanying drawing explanation

Fig. 1 is 2007-2009 of the present invention mean wind direction rose diagram in each season.

Fig. 2 is the present invention's on-the-spot position-finding point arrangenent diagram.

Fig. 3 is the comparison diagram of instantaneous wind speed change in monitoring point inside and outside anti-wind net.

Fig. 4 is the mean dust concentration figure of each measurement point.

Fig. 5 is the daily TSP concentration profile of monitoring point.

Embodiment

The invention provides the method for prediction windproof effect of windproof net in coal field area, the method subtracts dirt effect to the Summing Factor of becalming of anti-wind net respectively and measures, in order to make object of the present invention, technical scheme and advantage clearer, clear and definite, below with reference to accompanying drawing and embodiment, the present invention is described in more detail.

Coal yard measured by the present invention is the coal yard 1 of PORT OF QINHUANGDAO, and harbour, Qinhuangdao forms primarily of three stockyards, is respectively stockyard 1, stockyard 2 and stockyard 3.The storage area in stockyard 1 is 660000 square metres, and heap place has 56 stackings, and point seven row eight row, these stackings are the trapezoidal stacking of taper flat-top that continuous print is identical.

Shown in wind rose as seasonal in Fig. 1, according to the statistics of 2007 to 2009 years weather observation data, cardinal wind is northeaster, and frequency is 15.44%; Next is east wind, and frequency is 13.41%, and average of the whole year wind speed is 2.03m/s, and cardinal wind annual mean wind speed is 1.94m/s.Due to the specific geographical conditions in PORT OF QINHUANGDAO, it is positioned at bank of the Bohai Sea, the coal dust of open coal yard is blown away by high wind and local fitful wind, particularly at the season of occurrence in summer, considers coal yard landform and climatic factor, anti-wind net is arranged in the east along Coal Stack Yard 3 phase in 2009 and south, total length is 2071m, is highly 23m, and the average height of dump is 6m, its anti-wind net sheet material adopts aluminum-zinc alloy metal wind shutter, and anti-wind net factor of porosity is 0.4.

As shown in Figure 2, in figure (a) for anti-wind net becalm the factor mensuration in the distribution plan of measurement point 1-16 and the distribution plan of coal yard External Reference point thereof in coal yard, as can be seen from figure (a), the coal yard 1 surveyed is seven row eight row, 56 stackings altogether, measurement point chosen four rows and four columns, and in the horizontal direction, a dump buttress is had between every two adjacent measurement points, in vertical direction, also be have a dump buttress between every two adjacent measurement points, that is, in level, in vertical direction, measurement point is arranged every a dump buttress, shown in figure (a): anti-wind net is arranged on southern direction and the east direction of coal yard, first row is followed successively by from south to north, second row ... until the 7th row, be followed successively by first row from the east to the west, secondary series ... until the 8th row, from the 7th row of first row, measurement point 1 is set, 5th row measurement point 2, 3rd row measurement point 3, first row measurement point 4, the 7th row ginseng measurement point 5 of the 3rd row ... until the first row measurement point 16 of the 7th row, reference point is chosen at the position apart from 575m in eastern anti-wind net horizontal direction, apart from the position of southern anti-wind net 690m, and the height of reference point is distance ground 10m.

Certainly, choosing of measurement point also can in the following manner, and in Fig. 2, (a) is not shown, measurement point 1 can from the 8th row of first row, measurement point 2 is arranged on first and ranked sixth row, is also to arrange every a dump buttress ... until measurement point 16 is positioned at the 7th and ranked second row.The choosing mainly to get rid of and block the impact that wind speed is reduced between stacking of measuring point in stockyard, survey wind speed and truly can reflect anti-wind net, instead of stockyard is to the performance of becalming of stacking.The position of measurement point and reference point selects ZDR-1F wind speed and direction self-recording device to measure after choosing, all wind speed and direction self-recording devices simultaneously, synchro measure.By wind speed and direction self-recording device in the vertical direction of 16 measurement points chosen and a reference point, height is stored up according to the actual of stacking, move up and down measurement, and its moving direction is piled up neatly ground all the time and kept vertical with dump, its vertical mobile height distance dump buttress basal surface (i.e. the vertical height on distance ground) must not more than 10m.Wind direction and wind velocity registering instrument carries out one-shot measurement in every 10 seconds, and records the measurement point air speed data x of every 10 seconds _irepresent, every 2 minutes records mean value is used represent; Measuring method and the measurement point of reference point are the same, and record obtains the reference point air speed data x of every 10 seconds _iefrepresent, the mean value of every 2 minutes records is used represent, the measurement point air speed data number N in 2 minutes represents, because the mensuration of measurement point and the mensuration of reference point are synchronously carried out, the air speed data number in reference point 2 minutes is also represent with N.

Data x _i, x _{i, ref}, after having processed, substitute in following formula (a) and formula (b):

$\mathrm{\σ}\left(z\right)=\sqrt{\frac{\mathrm{\Σ}{(x_i-\stackrel{\‾}{x})}^2}{N-1}}---\left(a\right)$

${\mathrm{\σ}}_{\mathrm{ref}}=\sqrt{\frac{\underset{i}{\overset{N}{\mathrm{\Σ}}}{(x_{i,\mathrm{ref}}-{\stackrel{\‾}{x}}_{\mathrm{ref}})}^2}{N-1}}---\left(b\right)$

Z in formula (a) is the vertical height of distance dump buttress basal surface (i.e. distance ground), calculate the velocity standard deviation of measurement point velocity standard deviation and reference point outside the venue in appearing on the scene, then by the velocity standard deviations of measurement point velocity standard deviations (z) with reference point outside the venue _refsubstitute in following formula (c):

$R_{\mathrm{uz}}=\frac{U\left(z\right)+\mathrm{\σ}\left(z\right)}{U_{\mathrm{ref}}+{\mathrm{\σ}}_{\mathrm{ref}}}---\left(c\right)$

In formula: U (z)---the average velocity of measurement point when distance dump buttress ground vertical range is z rice, m/s;

σ (z)---measurement point velocity standard deviation when distance dump buttress ground vertical range is z rice;

U _ref---the average velocity of coal yard district External Reference point, m/s;

σ _ref---the velocity standard deviation of coal yard district External Reference point;

The factor of becalming of the anti-wind net of this period can be calculated.

Consider that annual natural wind is to continuous change, different wind vector, on the impact of the factor of becalming, proposes the becalm computing formula of the factor of average of the whole year as follows:

$\mathrm{\ζ}=\underset{i=1}{\overset{8}{\mathrm{\Σ}}}{\stackrel{\‾}{R}}_{u,z}\×f_i---\left(\text{d}\right)$

Wherein: ζ---annual is becalmed the factor;

F _i---the respective frequency distribution of annual 8 wind directions, see Fig. 1;

---in during monitoring, the mean value of the factor of becalming under each wind direction.

As shown in Figure 2, in figure, (b) subtracts the layout of institute's selecting and purchasing point in the mensuration of dirt effect for anti-wind net, can find out in figure (b): coal on-site is provided with three sampled points, T1, T2, T3 respectively, coal yard district is outside equipped with three sampled points T4, T5, T6, all samples are on the central axis of main anti-wind net (main anti-wind net is east side anti-wind net), and all sampled points are 10m apart from the vertical range on ground.According to coal dust Diffusion Law, the some position of these sampled points is arranged centered by the prevailing wind direction of stockyard, the non-homogeneous increasing of sampled distance.Wherein, the T3 sampled point of coal on-site is nearest apart from eastern anti-wind net, and horizontal range is 100m, is secondly the horizontal range 250m of T2 sampled point to eastern anti-wind net, and T1 sampled point is 400m to the horizontal range of eastern anti-wind net farthest; In three sampled points outside coal yard district, T4 sampled point is 100m apart from the distance of eastern anti-wind net, T5 sampled point is 250m apart from the distance of eastern anti-wind net, apart from eastern anti-wind net farthest, its horizontal range is 400m to T6 sampled point, that is, T4 and T3, T5 and T2, T6 and T1 are symmetrical mutually with east side anti-wind net between two, without any barrier around T6 sampled point, as the reference point position of dust concentration, to monitor the background value of stockyard dust concentration.

In order to better the present invention is described, as shown in Figure 3.Fig. 3 shows the instantaneous wind speed change of measuring wind speed point 6 and wind speed reference point.As can be seen from Figure 3: be starkly lower than the wind speed outside anti-wind net at the wind speed of anti-wind net inside, indicate anti-wind net and significantly cover choke performance.

As shown in Figure 4, Fig. 4 is PM10-2.5 and the TSP comparison diagram of the different sampled point of distance anti-wind net, as can be seen from the figure: the sampled point outside coal yard district, mass concentration as T4 sampled point, T5 sampled point and T6 sampled point all decreases, especially nearest apart from eastern anti-wind net T4 sampled point, in its TSP concentration ratio net, the TSP value of T3 sampled point is low by 14%.As shown in Figure 5, this means that the high density pollution in air is mainly limited in coal on-site.Height due to anti-wind net is greater than dump height, and most dust can not cross anti-wind net, only has minority particle can cross from anti-wind net top.In addition, due to the Intercepting effects of anti-wind net, wind speed reduces, as not growing distance load bearing grain thing, so these have all directly been dropped on around anti-wind net by the particle promoted.Therefore, the particle concentration of T5 sampled point is lower than the value of T4 sampled point.Can judge that the subtract dirt efficiency of anti-wind net to TSP powder dust particle is greater than 10% thus.

Should be understood that; the above-mentioned description for embodiment is comparatively detailed; therefore the restriction to scope of patent protection of the present invention can not be thought; those of ordinary skill in the art is under enlightenment of the present invention; do not departing under the ambit that the claims in the present invention protect; can also make the various deformation such as replacement, simple combination, request protection domain of the present invention should be as the criterion with claims.

Claims (4)

1. monitor a method for windproof effect of windproof net in coal field area, described method comprises the becalm mensuration of the factor and anti-wind net of anti-wind net and subtracts the mensuration of dirt effect, it is characterized in that: the becalm mensuration of the factor of described anti-wind net comprises the following steps:

A, 16 measurement points are chosen at coal on-site, described measurement point is distributed with four rows and four columns at coal on-site, and each row is arranged every a dump buttress in the horizontal direction, each row is arranged every a dump buttress in vertical direction, described each measurement point is all chosen at the center of dump buttress upper surface, a wind speed is chosen with reference to measuring point outside coal yard district, described wind speed is arranged on the east side of eastern anti-wind net with reference to measuring point, and the horizontal range of itself and eastern anti-wind net is 25 times of eastern anti-wind net net height, with 30 times that the vertical range of southern anti-wind net is southern anti-wind net net height, the surrounding of described wind speed reference measuring point is without any barrier,

After b, step a complete, ZDR-1F wind speed and direction self-recording device is selected to measure, all wind speed and direction self-recording devices are measured simultaneously, wind speed and direction self-recording device highly moves up and down measurement according to actual the storing up of stacking in the vertical direction along 16 measurement points chosen in step a and a reference point, and its vertical mobile height distance dump buttress ground must not more than 10m, wind direction and wind velocity registering instrument carries out one-shot measurement in every 10 seconds, records the measuring point air speed data x of every 10 seconds _irepresent, every 2 minutes records mean value is used represent, test duration every day is monitoring continuously in 24 hours, and during follow-on test, number is 5-7 days;

The measurement point velocity standard deviation of c, calculating coal on-site, according to formula wherein: N is any one measurement point air speed data number in 2 minutes; x _ifor the measurement point air speed data of every 10 seconds in step b; for the mean value of every 2 minutes records in step a;

D, the reference point velocity standard deviation calculated outside coal yard district, according to formula wherein: N is the reference point data amount check in 2 minutes; x _{i, ref}for the reference point air speed data of every 10 seconds; for the mean value of the reference point of every 2 minutes records; Test and the test of each measurement point of above-mentioned reference point are synchronously to be carried out simultaneously;

E, according to formula calculate the factor of becalming when distance floor level is z rice, wherein:

U (z)---the average velocity of measurement point when distance dump buttress ground vertical range is z rice, m/s;

σ (z)---measurement point velocity standard deviation when distance dump buttress ground vertical range is z rice;

U _ref---the average velocity of reference point, m/s;

σ _ref---the velocity standard deviation of reference point;

The mensuration that described anti-wind net subtracts dirt effect comprises the following steps: with main anti-wind net---and eastern anti-wind net is benchmark, at coal on-site, 3 concentration sample points are set, it draws near apart from eastern anti-wind net and is respectively T1, T2, T3,3 sampled points T4, T5, T6 are set outside coal yard district, in 3 sampled points at the circumference place in described coal yard district, T4 sampled point is nearest apart from eastern anti-wind net, and T6 sampled point apart from eastern anti-wind net farthest; Each sampled point is that straight line is arranged along the central axis of east side anti-wind net, T4 and T3, T5 and T2, T6 and T1 are symmetrical mutually with east side anti-wind net between two, large discharge TSP air sampler is adopted to measure at each sampled point, all sampled points are 10m apart from the vertical range on ground, test duration every day is continuous sampling in 24 hours, and during follow-on test, number is 5-7 days.

2. method according to claim 1, is characterized in that: described dump buttress is the identical trapezoidal stacking of flat-top, and the height of described eastern anti-wind net, southern anti-wind net is 23m, dump mean height 6m.

3. method according to claim 2, is characterized in that: described anti-wind net factor of porosity is 0.4.

4. method according to claim 3, is characterized in that: described sampled point T6 and sampled point T1 horizontal range are 800m.