A kind of building wind tunnel pressure measuring test data compression method
Technical field
The present invention relates to build wind tunnel pressure measuring test data compression method.
Background technology
Wind tunnel pressure measuring test is one of committed step of current large complicated engineering structure wind force proofing design.Wind tunnel pressure measuring is tested
The wind loads time course data amount obtained is big, up to GB even TB rank, and contains abundant information.Big data quantity result in
The difficulty that data store and analyze, therefore, it is necessary to carry out feature extraction and compression storage, in order to amassing of data to data
Tire out, analyze and predict.The wind load time-history data characteristics that building wind tunnel test obtains can be attributed to the mark that non-gaussian part is relevant
Amount field.Current wind tunnel test data compression, many employing eigenvector methods, pay close attention to the wind load field principal coordinate information in time domain,
Or the Time-domain Statistics information of wind load time-history is modeled, wind load frequency domain characteristic and dependency are paid close attention to less, causes number
Deviation and the error in actual application according to compression.
Summary of the invention
The present invention is to solve to pay close attention to less to wind load frequency domain characteristic and dependency in prior art, causing data pressure
The problem of the error in the deviation of contracting and actual application, and a kind of building wind tunnel pressure measuring test data compression method proposed.
A kind of building wind tunnel pressure measuring test data compression method realizes according to the following steps:
Step one: blast time series data nondimensionalization building wind tunnel test pressure measurement obtained is coefficient of wind pres time-histories
Data, and the unbiased esti-mator meansigma methods of rated wind pressure coefficient, root-mean-square value, degree of bias value and and kurtosis value;
Step 2: coefficient of wind pres time-histories carries out auto-power spectrum and estimates to obtain auto-power spectrum, calculates dimensionless power and sets a song to music
The peak value of line and curve high band slope under log-log coordinate;
Step 3: use Welch method to estimate the coherent function of coefficient of wind pres field, with exponential function matching coherent function;
Step 4: solve the equation of band Bata function according to step 2 and obtain the expression formula of dimensionless auto-power spectrum, and root
According to Beta function call to any ν rank dimensionless spectral moment;
Step 5: form the wind load data after compression according to step one, step 3 and step 4;
Step 6: according to Hermite multinomial transfer function, forms cross-spectrum matrix and is reconstructed wind-pressure field;
Step 7: estimate extreme value wind load;
Step 8: computation structure wind vibration response.
Invention effect:
The present invention is a kind of building wind tunnel pressure measuring test data compression side based on Hermite multinomial and Beta function
Method, can by the building wind tunnel pressure measuring data compression of GB, TB rank to KB, MB rank, to wind load in time, spatial variations
A kind of novel information of the big data of higher-dimension time-histories extracts and modeling method, is finally reached the purpose of data compression.The present invention's is excellent
Gesture is, modeling process is the simplest, it is possible to obtain the data form of efficient storage and application, it is simple to the deep excavation of data.
By Hermite multinomial, the statistical information of data can be reconstructed, and by Beta function theory, spectrum information be entered
Line reconstruction, finally combines stochastic simulation technology and can rebuild the wind-pressure field of compression.From the application angle of structural wind resistance design, compress number
According to the Wind resistant analysis of engine request can be carried out, simplify loaded down with trivial details time-histories and spectrum analysis process, more practical.
Accompanying drawing explanation
Fig. 1 is flow chart of the present invention;
Fig. 2 is that blast based on Bata function composes modeling result figure;
Fig. 3 (a) is normalized coefficient of wind pres time-histories figure;In figure, abscissa is time tkS (), vertical coordinate is normalized
Coefficient of wind pres time-histories
Fig. 3 (b) is coefficient of wind pres probability density function figure, and in figure, abscissa is normalized coefficient of wind presVertical coordinate is probability density function;
Fig. 3 (c) coefficient of wind pres dimensionless power spectral density function figure;In figure, abscissa is frequency f (Hz);Vertical coordinate is nothing
Dimension power spectral density function S;
Fig. 4 is the comparison diagram of extreme value wind load estimated result based on Hermite multinomial transfer function method and actual value;
Fig. 5 is the comparison diagram of flat plate framed structure wind vibration response and the initial data result of calculation carried out based on compression data.
Detailed description of the invention
Detailed description of the invention one: as it is shown in figure 1, a kind of building wind tunnel pressure measuring test data compression method includes following step
Rapid:
Step one: blast time series data nondimensionalization building wind tunnel test pressure measurement obtained is coefficient of wind pres time-histories
Data, and the unbiased esti-mator meansigma methods of rated wind pressure coefficient, root-mean-square value, degree of bias value and and kurtosis value;
Step 2: coefficient of wind pres time-histories carries out auto-power spectrum and estimates to obtain auto-power spectrum, calculates dimensionless power and sets a song to music
The peak value of line and curve high band slope under log-log coordinate;
Step 3: use Welch method to estimate the coherent function of coefficient of wind pres field, with exponential function matching coherent function;
Step 4: solve the equation of band Bata function according to step 2 and obtain the expression formula of dimensionless auto-power spectrum, and root
According to Beta function call to any ν rank dimensionless spectral moment;
Step 5: form the wind load data after compression according to step one, step 3 and step 4;
Step 6: according to Hermite multinomial transfer function, forms cross-spectrum matrix and is reconstructed wind-pressure field;
Step 7: estimate extreme value wind load;
Step 8: computation structure wind vibration response.
Detailed description of the invention two: present embodiment is unlike detailed description of the invention one: will building in described step one
The blast time series data nondimensionalization that wind tunnel test pressure measurement obtains is coefficient of wind pres time course data, the nothing of rated wind pressure coefficient
Partially estimated mean value, root-mean-square value, degree of bias value and and kurtosis value particularly as follows:
Blast time series data p that building wind tunnel test pressure measurement is obtainedi(tk), when nondimensionalization is coefficient of wind pres
Number of passes evidenceWherein said i represents measuring point number, and t is the time, k express time serial number, and value is
1,2 ..., N, N are sampling length, and ρ is atmospheric density, and U represents and flows wind speed at reference altitude;And rated wind pressure coefficient
Unbiased esti-mator meansigma methodsRoot-mean-square valueDegree of bias valueAnd kurtosis value
Other step and parameter are identical with detailed description of the invention one.
Detailed description of the invention three: present embodiment is unlike detailed description of the invention one or two: right in described step 2
Coefficient of wind pres time-histories carries out auto-power spectrum and estimates to obtain auto-power spectrum, and the peak value and the curve that calculate dimensionless power spectrum curve are high
Frequency range slope under log-log coordinate particularly as follows:
Use autoregression AR model to carry out auto-power spectrum estimation to carrying out coefficient of wind pres time-histories, obtain auto-power spectrum SCp(f),
To its nondimensionalization, it is expressed asFrequency f nondimensionalization isWherein L represents with reference to yardstick;Calculate
The peak value of dimensionless power spectrum curve S-F curve, i.e. Sm=max{S (F) }, Fm=argmax{S (F) };And curve high band
Slope under log-log coordinate
In formula, K is half Fourier transformation length, Fk(k=1,2 ..., K) it is discrete dimensionless frequency, j is high band
The index of frequency, takes Fj=1.5Fm。
Other step and parameter are identical with detailed description of the invention one or two.
Detailed description of the invention four: present embodiment is unlike one of detailed description of the invention one to three: described step 3
Middle employing Welch method estimates the coherent function of coefficient of wind pres field, by the detailed process of exponential function matching coherent function is:
Welch method is used to estimate the coherent function Coh of coefficient of wind pres fieldijF (), uses exponential function Cohij(f)=exp (-kc
||f·Dij/ U) matching coherent function, wherein DijRepresent the distance of point-to-point transmission, i.e.
In formula, Δ f=fs/ 2K is frequency interval, fsFor sample frequency, kcFor relevant index, U is for flowing with reference to wind speed.
Other step and parameter are identical with one of detailed description of the invention one to three.
Detailed description of the invention five: present embodiment is unlike one of detailed description of the invention one to four: described step 4
In solve the equation of band Bata function and obtain the expression formula of dimensionless auto-power spectrum, and according to Beta function call to any ν rank without
The detailed process of dimension spectral moment is:
Solve the equation of band Bata function
Obtain frequency index α of blast spectrum, obtain the expression formula of dimensionless auto-power spectrum furtherWherein F '=F/Fm;According to Beta function, obtain any ν rank dimensionless spectral moment
Obtain normalized second order spectral moment further:
Other step and parameter are identical with one of detailed description of the invention one to four.
Detailed description of the invention six: present embodiment is unlike one of detailed description of the invention one to five: described step 5
Middle formed compression after wind load data particularly as follows:
Form the wind load data after compression, be expressed as 13 column data:
Front 3 row are measuring point three-dimensional geometry coordinates;4~7 are classified as Fourth square before wind load, represent average blast system respectively
Number, root-mean-square coefficient of wind pres, the coefficient of wind pres degree of bias, coefficient of wind pres kurtosis, 8~10 are classified as the auto-power spectrum model of wind load, point
Not Biao Shi dimensionless spectrum peak frequency, dimensionless spectrum peak and blast spectrum attenuation slope, 11 are classified as wind load coherency function model,
Representing relevant index, 12~13 are classified as derived parameter, represent the frequency index of blast spectrum, normalized second order spectral moment respectively.
Other step and parameter are identical with one of detailed description of the invention one to five.
Detailed description of the invention seven: present embodiment is unlike one of detailed description of the invention one to six: described step 6
Middle according to Hermite multinomial transfer function, form cross-spectrum matrix and wind-pressure field is reconstructed particularly as follows:
Wind-pressure field is rebuild based on Hermite multinomial transfer function method, according to Hermite multinomial transfer function, in conjunction with
Characterize the statistical parameter γ of non-Gaussian feature3=Cp,sk、γ4=Cp,ku, set up nongausian process x (t) and Gaussian process u (t)
Contact, it may be assumed that
Work as Cp,kuWhen >=3, x=h (u)=κ [u+h3(u2-1)+h4(u3-u)], Or be expressed asξ (x)=1.5b (a+x/ κ)-a3, a=h3/
3h4, b=1/3h4, c=(b-1-a2)3;
Work as Cp,ku< when 3, u=h-1(x)=b2x+b3(x2-γ3x-1)+b4(x3-γ4x-γ3),
Expression formula in conjunction with crosspower spectrumCross-spectrum matrix [the S formedCp
(ω)], press
Wind-pressure field is reconstructed, wherein Hkm(ωml) it is crosspower spectrum matrix [SCp(ω) Cholesky] decomposes, θkm
(ωml) it is Hkm(ωml) explement,For discrete frequency, Δ ω is between circular frequency
Every, φmlFor additive phase angle.
Other step and parameter are identical with one of detailed description of the invention one to six.
Detailed description of the invention eight: present embodiment is unlike one of detailed description of the invention one to seven: described step 7
Middle according to step 6 estimate extreme value wind load particularly as follows:
Hermite multinomial transfer function based on step 6 estimates extreme value wind load,gNG=h
(g),n0=λ0FmU/L is average cross-over frequency, and T=600s is with reference to duration.H () is
According to Hermite function x=h (u) determined by step 6=κ [u+h3(u2-1)+h4(u3-u)] or u=h-1(x)=b2x+
b3(x2-γ3x-1)+b4(x3-γ4x-γ3)。
Other step and parameter are identical with one of detailed description of the invention one to seven.
Detailed description of the invention nine: present embodiment is unlike one of detailed description of the invention one to eight: described step 8
The middle detailed process according to step 6 computation structure wind vibration response is:
Press according to the wind load cross-spectrum matrix of reduction in step 6
Wherein said [H (ω)]={ ω2[M]+iω[C]+[K]}-1For frequency response function matrix, [M] is mass matrix, and [C] is damping square
Battle array, [K] is stiffness matrix,For imaginary unit, [SCp(ω) being] the cross-spectrum matrix calculated according to step 6, [R] is attached
Belonging to area transition matrix, subscript * represents that conjugate transpose, T represent transposition, and-1 represents inverse matrix, computation structure wind vibration response association side
Difference [∑x]。
Other step and parameter are identical with one of detailed description of the invention one to eight.
Embodiment one:
Flat roof system series wind tunnel test, has investigated the length-width ratio of roof system, depth-width ratio, landforms, wind speed, scaling factor, wind direction
Impact, has carried out the wind tunnel test of 286 operating modes altogether, and experimental data size is 84.9GB, after data compression of the present invention, and data
Size is 12.9MB, is embodied as step as follows:
Step one: carry out statistical analysis after blast time-histories nondimensionalization wind tunnel test recorded, try to achieve coefficient of wind pres
Front Fourth square.
Step 2: coefficient of wind pres time-histories is carried out auto-power spectrum analysis, has solved auto-power spectrum parameter Sm、Fm、k2, Fig. 2 gives
Go out modeling result.
Step 3: coefficient of wind pres time-histories has carried out analysis and the matching of coherent function, has solved being concerned with under each operating mode
Index kc。
Step 4: the auto-power spectrum parametric solution the obtaining step 3 equation containing Beta function, has obtained deriving ginseng
Number α and λ0。
Step 5: the result that step one~four obtain is integrally formed the output of the wind load data file after compression.
For verifying the effectiveness of this invention, the most also carry out reconstructing (step 6) by compression data, found based on this
Bright method, compression data keep consistent with the statistics of initial data, frequency spectrum, correlation properties, illustrate the suitability of the method.
Additionally, for ease of engineer applied, the most also use the compression data estimation extreme value wind load (step 7) of flat roof system, with various
The exact method of this (1000 sample) is contrasted, and finds the actual value of analogue value energy envelope more than 95%, relative when underestimating
Error, within 10%, may be used in engineering Design of Retaining Structure;For the wind-induced response of agent structure, according to step
Eight result of calculations giving different flat plate framed structure, the error of discovery dynamic respond is within 5%, and result is more accurate, available
In engineering structure wind force proofing design, experimental result is if Fig. 3 (a) is to shown in Fig. 5.
In sum, the present invention is in processing building wind tunnel pressure measuring test data, it is possible to the storage significantly reducing data is empty
Between, the data result obtained has stronger reducibility, and relatively broad engineering use value.