CN105095629A - Wind pressure non-uniform coefficient calculation method based on measured data - Google Patents

Abstract

The present invention relates to a wind pressure non-uniform coefficient determination method based on measured data. The method comprises the following steps: (1) determining an apparent wind load at a single point on a lead wire; (2) determining the apparent wind load of a whole-span lead wire; (3) determining an actual wind load of the whole-span lead wire; and (4) determining a wind pressure non-uniform coefficient. The wind pressure non-uniform coefficient obtained by the method provides more real reflection of spatial relevance of the wind load, and the influence of strong fluid-structure interaction between the lead wire and air flow is accurately taken into account.

Description

A kind of wind evil attacking lung computing method based on measured data

Technical field:

The present invention relates to a kind of wind evil attacking lung defining method, more specifically relate to a kind of wind evil attacking lung defining method based on measured data.

Background technology:

First wire wind evil attacking lung needs the wind speed along whole shelves arrangement of conductors, and carry out field measurement in the inclination data of this wind friction velocity lower wire suspension string, then adopt suitable computing method, obtain acting on the apparent wind load on wire and actual wind load, both ratio is wind evil attacking lung.

The computing formula of wind evil attacking lung is provided in current power industry specification " 110kV ~ 750kV overhead transmission line design specifications ", but how formulas for calculating does not obtain in interpretation of section, do not provide the method according to measured data rated wind pressure nonuniformity coefficient measured value yet.Under this background, the present invention, based on along wire uneven distribution air speed data and suspension string inclination data, provides a kind of based on the actual wind load of above-mentioned measured data inverse and apparent wind load ratio, the i.e. method of wind evil attacking lung.

Summary of the invention:

The object of this invention is to provide a kind of wind evil attacking lung defining method based on measured data, the wind evil attacking lung that the method obtains has reacted the spatial coherence of wind load more really, has accurately counted the impact of the strong fluid structure interaction between wire and air-flow.

For achieving the above object, the present invention is by the following technical solutions: a kind of wind evil attacking lung defining method based on measured data, said method comprising the steps of:

(1) determine that on wire, apparent wind load is located in a single point position;

(2) determine that whole shelves wire table is serve as a lookout load;

(3) the actual wind load of whole shelves wire is determined;

(4) wind evil attacking lung is determined.

A kind of wind evil attacking lung defining method based on measured data provided by the invention, the wind load in described step (1) is determined by following formula (1):

$P_i=0.5\mathrm{\ρ}{U}_i^2{\sin }^2{\mathrm{\φ}}_i{C}_d{l}_{i}D---\left(1\right)$

Wherein, ρ is atmospheric density, U _ifor certain measuring point observes mean wind speed, φ _ifor the angle of horizontal wind direction and wire bearing of trend, l _ifor the conductor length that this place, some position can represent, C _dfor the resistance coefficient of wire under current Reynolds Number level, D is diameter of wire.

A kind of wind evil attacking lung defining method based on measured data provided by the invention, in described step (2), whole shelves wire is provided with at least three Wind observation points.

Another preferred a kind of wind evil attacking lung defining method based on measured data provided by the invention, in described step (2), whole shelves wire is provided with three Wind observation points, and its wind load is determined by following formula (2):

P _c＝P _c1+P _c2(2)

Wherein, P _c1for whole shelves wire outermost conducting wire hanging point gets square, P _c2for another outermost conducting wire hanging point of whole shelves wire gets square.

A preferred a kind of wind evil attacking lung defining method based on measured data more provided by the invention, described whole shelves wire outermost conducting wire hanging point gets square P _c1determined by following formula (3):

$P_{c1}=0.5\mathrm{\ρ}{C}_{d}D\left(\frac{L}{3}\right)\{1/6U_1^2\sin {\mathrm{\φ}}_1^2+3/6U_2^2\sin {\mathrm{\φ}}_2^2+5/6U_3^2\sin {\mathrm{\φ}}_3^2\}---\left(\text{3}\right)$

Wherein, L is wire span, U ₁be the mean wind speed that the first measuring point observes, φ ₁it is the angle that the first measuring point observes horizontal wind direction and wire bearing of trend; U ₂be the mean wind speed that the second measuring point observes, φ ₂it is the angle that the second measuring point observes horizontal wind direction and wire bearing of trend; U ₃be the mean wind speed that the 3rd measuring point observes, φ ₃it is the angle that the 3rd measuring point observes horizontal wind direction and wire bearing of trend.

Another preferably a kind of wind evil attacking lung defining method based on measured data provided by the invention, described another outermost conducting wire hanging point of whole shelves wire gets square P _c2determined by following formula (4):

$P_{c2}=0.5\mathrm{\ρ}{C}_{d}D\left(\frac{L}{3}\right)\{1/6U_6^2\sin {\mathrm{\φ}}_6^2+3/6U_5^2\sin {\mathrm{\φ}}_5^2+5/6U_4^2\sin {\mathrm{\φ}}_4^2\}---\left(4\right)$

Wherein, L is wire span, U ₆be the mean wind speed that the 6th measuring point observes, φ ₆it is the angle that the 6th measuring point observes horizontal wind direction and wire bearing of trend; U ₅be the mean wind speed that the 5th measuring point observes, φ ₅it is the angle that the 5th measuring point observes horizontal wind direction and wire bearing of trend; U ₄be the mean wind speed that the 4th measuring point observes, φ ₄it is the angle that the 4th measuring point observes horizontal wind direction and wire bearing of trend.

Another preferably a kind of wind evil attacking lung defining method based on measured data provided by the invention, in described step (3), actual wind load is determined by following formula (5):

$P_m=W_d\tan \stackrel{\‾}{\mathrm{\θ}}---\left(5\right)$

Wherein, W _dthe wire distributed for certain conducting wire hanging point place and suspension string gravity, for suspension string dip mean in the period corresponding to the Wind observation time period.

Another preferably a kind of wind evil attacking lung defining method based on measured data provided by the invention, the wind evil attacking lung in described step (4) is determined by following formula (6):

α＝P _m/P _C(6)

With immediate prior art ratio, the invention provides technical scheme and there is following excellent effect

1, the present invention is based on measured data analysis to realize, better can consider many factors, as roughness of ground surface, turbulence integral scale, the especially impact of the strong Coupling effect of seepage rock deformation of wire and ambient gas, the wind evil attacking lung obtained is more true and reliable;

2, the present invention lays a good foundation for surveying wire wind evil attacking lung;

3, the present invention is for obtaining wire wind evil attacking lung, provides measurement method and measured data support;

4, the uneven coefficient degree of accuracy of the blast drawn of method of the present invention is high.

Accompanying drawing explanation

Fig. 1 is the inventive method schematic flow sheet;

Fig. 2 is that certain continuous two grades of wire table of the present invention are serve as a lookout the distribution schematic diagram of load along wire;

1-anemoscope mounting points position; 2-suspension string drift indicator mounting points position.

Embodiment

Below in conjunction with embodiment, the invention will be described in further detail.

Embodiment 1:

As shown in Figure 1-2, the invention of this example is obtain the blast uneven distribution coefficient of LGJ-800/70 type wire under 300m span condition.Wind observation point position and suspension string angle of wind deflection observation station position are arranged as shown in Figure 1.In continuous print two grades of spans, in every 1/3rd spans, arrange a Wind observation point, amount to 6 Wind observation points.

First the apparent wind load P at each point position place is calculated based on formula (1) ₁~ P ₆, its calculating parameter value as shown in appendix 1.

$P_i=0.5\mathrm{\ρ}{U}_i^2{\sin }^2{\mathrm{\φ}}_i{C}_d{l}_{i}D---\left(1\right)$

Wherein, ρ is atmospheric density, U _ifor certain measuring point observes mean wind speed, φ _ifor the angle of horizontal wind direction and wire bearing of trend, l _ifor the conductor length that this place, some position can represent, C _dfor the resistance coefficient of wire under current Reynolds Number level, D is diameter of wire.

Determining the apparent wind load P at each point position place ₁~ P ₆after, get square to conducting wire hanging point A, row moment of flexure balance equation, can obtain following relational expression:

$P_{c1}=0.5\mathrm{\ρ}{C}_{d}D\left(\frac{L}{3}\right)\{1/6U_1^2\sin {\mathrm{\φ}}_1^2+3/6U_2^2\sin {\mathrm{\φ}}_2^2+5/6U_3^2\sin {\mathrm{\φ}}_3^2\}---\left(\text{3}\right)$

Wherein, L is wire span, U ₁be the mean wind speed that the first measuring point observes, φ ₁it is the angle that the first measuring point observes horizontal wind direction and wire bearing of trend; U ₂be the mean wind speed that the second measuring point observes, φ ₂it is the angle that the second measuring point observes horizontal wind direction and wire bearing of trend; U ₃be the mean wind speed that the 3rd measuring point observes, φ ₃it is the angle that the 3rd measuring point observes horizontal wind direction and wire bearing of trend.

Get square to conducting wire hanging point B, row moment of flexure balance equation, can obtain following relational expression:

$P_{c2}=0.5\mathrm{\ρ}{C}_{d}D\left(\frac{L}{3}\right)\{1/6U_6^2\sin {\mathrm{\φ}}_6^2+3/6U_5^2\sin {\mathrm{\φ}}_5^2+5/6U_4^2\sin {\mathrm{\φ}}_4^2\}---\left(4\right)$

Wherein, L is wire span, U ₆be the mean wind speed that the 6th measuring point observes, φ ₆it is the angle that the 6th measuring point observes horizontal wind direction and wire bearing of trend; U ₅be the mean wind speed that the 5th measuring point observes, φ ₅it is the angle that the 5th measuring point observes horizontal wind direction and wire bearing of trend; U ₄be the mean wind speed that the 4th measuring point observes, φ ₄it is the angle that the 4th measuring point observes horizontal wind direction and wire bearing of trend.

Then there is following relational expression at hanging point C place:

$\begin{array}{c}{P}_c=P_{c1}+P_{c2}\\ =0.5\mathrm{\ρ}{C}_{d}D\left(\frac{L}{3}\right)\{(5/6)(U_1^2\sin {\mathrm{\φ}}_1^2+U_6^2\sin {\mathrm{\φ}}_6^2)+\\ (3/6)(U_2^2\sin {\mathrm{\φ}}_2^2+U_5^2\sin {\mathrm{\φ}}_5^2)+(1/6)(U_3^2\sin {\mathrm{\φ}}_3^2+U_4^2\sin {\mathrm{\φ}}_4^2)\}\end{array}---\left(2\right)$

Parameter in subordinate list 1 being substituted in above formula and obtaining whole shelves wire table load of serveing as a lookout is P _cfor 2185N.

LGJ-800/70 type wire every meter of quality 2.791kg, the gravity 8205N of 300m long lead has been carried on a shoulder pole in the punishment of C hanging point shown in accompanying drawing 1, suspension string quality 147.5kg, the then W at hanging point C place _dfor 9650.5N.The suspension string dip mean corresponding with air speed data in present period it is 10 °, by W _dwith be worth and obtain in following formula (5), P _mfor 1701.6N.Again by P _mand P _cvalue is updated to and obtains wind evil attacking lung α in formula (6) is 0.6421.

$P_m=W_d\tan \stackrel{\‾}{\mathrm{\θ}}---\left(5\right)$

α＝P _m/P _C(6)

Wherein, W _dthe wire distributed for certain conducting wire hanging point place and suspension string gravity, for suspension string dip mean in the period corresponding to the Wind observation time period.

Table 1

ρ(kg/m 3)	C d	l 1～l 6(m)	D(m)	U 1sinφ 1
					1.225	1.1	100	0.039	16.8
U 2sinφ 2	U 3sinφ 3	U 4sinφ 4	U 5sinφ 5	U 6sinφ 6
					18.0	18.5	18.0	16.8	14.8

Finally should be noted that: above embodiment is only in order to illustrate that technical scheme of the present invention is not intended to limit, although with reference to above-described embodiment to invention has been detailed description, those of ordinary skill in the field are to be understood that: still can modify to the specific embodiment of the present invention or equivalent replacement, and not departing from any amendment of spirit and scope of the invention or equivalent replacement, it all should be encompassed in the middle of this right.

Claims (8)

1., based on a wind evil attacking lung defining method for measured data, it is characterized in that: said method comprising the steps of:

(1) determine that on wire, apparent wind load is located in a single point position;

(2) determine that whole shelves wire table is serve as a lookout load;

(3) the actual wind load of whole shelves wire is determined;

(4) wind evil attacking lung is determined.

2. a kind of wind evil attacking lung defining method based on measured data as claimed in claim 1, is characterized in that: the wind load in described step (1) is determined by following formula (1):

Wherein, ρ is atmospheric density, U _ifor certain measuring point observes mean wind speed, φ _ifor the angle of horizontal wind direction and wire bearing of trend, l _ifor the conductor length that this place, some position can represent, C _dfor the resistance coefficient of wire under current Reynolds Number level, D is diameter of wire.

3. a kind of wind evil attacking lung defining method based on measured data as claimed in claim 2, is characterized in that: in described step (2), whole shelves wire is provided with at least three Wind observation points.

4. a kind of wind evil attacking lung defining method based on measured data as claimed in claim 3, is characterized in that: in described step (2), whole shelves wire is provided with three Wind observation points, and its wind load is determined by following formula (2):

P _c＝P _c1+P _c2(2)

Wherein, P _c1for whole shelves wire outermost conducting wire hanging point gets square, P _c2for another outermost conducting wire hanging point of whole shelves wire gets square.

5. a kind of wind evil attacking lung defining method based on measured data as claimed in claim 4, is characterized in that: described whole shelves wire outermost conducting wire hanging point gets square P _c1determined by following formula (3):

Wherein, L is wire span, U ₁be the mean wind speed that the first measuring point observes, φ ₁it is the angle that the first measuring point observes horizontal wind direction and wire bearing of trend; U ₂be the mean wind speed that the second measuring point observes, φ ₂it is the angle that the second measuring point observes horizontal wind direction and wire bearing of trend; U ₃be the mean wind speed that the 3rd measuring point observes, φ ₃it is the angle that the 3rd measuring point observes horizontal wind direction and wire bearing of trend.

6. a kind of wind evil attacking lung defining method based on measured data as claimed in claim 4, is characterized in that: described another outermost conducting wire hanging point of whole shelves wire gets square P _c2determined by following formula (4):

Wherein, L is wire span, U ₆be the mean wind speed that the 6th measuring point observes, φ ₆it is the angle that the 6th measuring point observes horizontal wind direction and wire bearing of trend; U ₅be the mean wind speed that the 5th measuring point observes, φ ₅it is the angle that the 5th measuring point observes horizontal wind direction and wire bearing of trend; U ₄be the mean wind speed that the 4th measuring point observes, φ ₄it is the angle that the 4th measuring point observes horizontal wind direction and wire bearing of trend.

7. a kind of wind evil attacking lung defining method based on measured data as claimed in claim 4, is characterized in that: in described step (3), actual wind load is determined by following formula (5):

Wherein, W _dthe wire distributed for certain conducting wire hanging point place and suspension string gravity, for suspension string dip mean in the period corresponding to the Wind observation time period.

8. a kind of wind evil attacking lung defining method based on measured data as claimed in claim 7, is characterized in that: the wind evil attacking lung in described step (4) is determined by following formula (6):

α＝P _m/P _C(6)