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Validation of the CFD program PHOENICS 2008 for the determination of wind loads on buildings. Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL . Validation of PHOENICS-2008 for the determination of wind pressures on buildings, by

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Slide1 l.jpg

Validation of the CFD program PHOENICS 2008

for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Validation of PHOENICS-2008 for the

determination of wind pressures on buildings, by

Frank Zimmermann, Heilbronn, D and

Dipl.-Ing. Frank Kanters, Heerlen, NL;

an English-language version by Brian Spalding.

  • Contents

  • 1. Foreword

  • Introduction

  • Boundary conditions

  • 4. Slender tower

  • 4.1 Wind-tunnel measurements

  • 4.2 CFD calculations

  • 4.3 Comparison with DIN 1055-4

  • 5. Cube-shaped buildings

  • 5.1 Wind-tunnel measurements

  • 5.2 CFD calculations

  • 5.3 Comparison with DIN 1055-4

  • 6. Rectangular buildings H = 0.5 B

  • 6.1 Wind-tunnel measurements

  • 6.2 CFD calculations

  • 6.3 Comparison with DIN 1055-4

  • 7. Summary of the results

  • and conclusions

  • References

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

1


Validation of the cfd program phoenics 2008 for the determination of wind loads on buildings l.jpg
Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

1.0 Foreword

DIN 1055-4 03/2005 permits the determination of wind loads on buildings of rectangular-plan shape

with sufficient accuracy. It gives however no guidance regarding buildings of more-complex shape.

Since knowledge of the wind loads is necessary for proper design, especially for tall buildings,

recourse therefore has in the past had to be made to measurements in wind tunnels, in which the

non-uniformity of wind profile and the presence of surrounding buildigs should be represented.

These requirements, together with the need for a large large number of measurement locations,

make the method costly.

For these and other reasons, better accuracy then +/- 15 % is not to be expected.

The development of Computational Fluids Dynamics, and of sufficiently powerful computer hardware,

now permit wind loads on buildings to be computed without great expense. The use of the large-eddy

turbulence model together with parallel processing leads to especially good results.

In the present report, the results of calculations made by means of the PHOENICS-2008 CFD-software

package are compared with experimental data and with the prescriptions of DIN 1055-4, and are

shown thereby to be sufficiently accurate.

Such calculations can be made for buildings of any shape.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

2


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

  • Introduction

  • A validation exercise requires knowledge of varied and reliable experimental data as standards of comparison.

  • In the present investigation, the following sources were used:

  • 1. NISTIR 6371, United States Department of Commerce, Technology Administration,

  • National Institute of Standards and Technology

  • Building and Fire Research Laboratory, Gaithersburg, [2].

  • 2. Numerical Prediction of Wind Loading on Buildings and Structures,

  • The working group for numerical prediction of wind loading on buildings and structures,

  • Subcommitee for wind engineering data unit for structural design,

  • Archtectural Institute of Japan, 1998, [3].

  • 3. DIN 1055-4, 03/2005, Einwirkungen auf Tragwerke, Teil 4: Windlasten, [4].

  • In [2] the numerical determination of wind loads by means of Large-Eddy Turbulence simulation is

  • compared with wind-tunnel measurements and with the large-eddy caculations by Shah und Ferziger [5].

  • Two building models were used: a tower of 10 x 10 x 80 m and a cube of 30 x 30 x 30 m.

  • A further comparison was made with the investigation of the AIJ – Report, Architectural Institute of Japan, [3]

  • for a rectangular-shaped building of 30 x 30 x 15 m which compared CFD calculations with wind-tunnel

  • measurements.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

3


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

  • Introduction (continued)

  • The validation was conducted by making calculations with the program Phoenics 2008 from CHAM, London

  • for the following buildings:

  • A. Tall Building 10 x 10 x 80 m

  • 1.1 with vref = constant (uniform Flow)

  • 1.2 with wind profile (shear Flow),

  • Exponent n = ¼ , roughness zo = 0,05 m

  • B. Cubical Building 30 x 30 x 30 m

  • 1.1 with vref = constant (uniform Flow)

  • 1.2 with wind profile (shear Flow),

  • Exponent n = ¼ , roughness zo= 0,05 m

  • C. Low Flat Building 30 x 30 x 15 m

  • 1.1 with vref = constant (uniform Flow)

  • 1.2 with wind profile (shear Flow),

  • Exponent n = ¼ , roughness zo = 0,05 m

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

4


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

  • Boundary conditions

  • The large-eddy model was chosen because of its advantages [6] . Calculations with the k-epsilon model

  • lead to more or less the same conclusions provided that one reaches convergence. The LE model is

  • specially suitable for fine grids.

  • The LE – Model proved to be more robust, and to converge faster than K-epsilon.

  • The choice of grid is of great importance in wind simulations.

  • PHOENICS uses a basically Cartesian grid; and it has two especially valuable features for providing fine

  • grids where they are needed and for handling surfaces which cut the grid planes obliquely. They are,

  • respectively:

  • FINE-GRID EMBEDDING and PARSOL.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Pressure contours and vectors between louvres

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

3. Boundary conditions (contd)

These features are illustrated in the picture on the right. PARSOL smooths the corners. The building shown has the dimensions

30 x 30 x 30 m and is turned through 45 ° .

The grid-cell size is 1 m.

FGE allowed the grid to be refined still further, without significantly altering the results.

The favourable grid generation and the absence of surrounding buildings allowed exemplary convergence to be achieved within 1000 sweeps.

For many applications other forms of grid are needed, such as cylindrical-polar for pipe-flow and body-fitted

for more complex shapes.

For flow around buildings however the combination of FGE and PARSOL is ideal.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

7


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

4.0 Tall building

4.1 Wind-tunnel measurements

Comparison between the predictions of PHOENICS and

the wind-tunnel measurements of NIST3671.

Comparisons were made for both uniform-flow and

shear-flow wind profiles.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

8


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

2

3

1

2

3

4

4

3

1

2

Wind

Side

Front

back

Windkanal, uniform Flow nach NIST6371

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Above: calculations with PHOENICS for uniform flow

Left: data from NIST6371

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

9


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

2

3

1

2

3

4

4

3

1

2

Wind

Side

Front

back

Windkanal, shear Flow nach NIST6371

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Above: calculations with PHOENICS for shear flow

Left: data from NIST6371

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

10


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

4.0 Tall Building

4.2 CFD calculations

The results computed by PHOENICS are compared with

the CFD calculations of NIST6371.

Comparison was made for both uniform and shear–low

wind profiles.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

11


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

2

3

1

2

3

4

4

3

1

2

Wind

Side

Front

back

Berechnung, uniform Flow nach NIST6371

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Above: calculations with PHOENICS for uniform flow

Left: data from NIST6371

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

12


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

2

3

1

2

3

4

4

3

1

2

Wind

Side

Front

back

Berechnung, shear Flow nach NIST6371

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Above: PHOENICS calculations for shear flow

Left: data from NIST6371

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

13


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

4.0 Tall Building

4.3 Comparison with DIN 1055-4

The results computed by PHOENICS are compared with

the values given by DIN 1055-4 .

The comparison is made for the uniform-flow wind profile.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

14


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Plan view

Table 3 – External-pressure coefficients for vertical walls of a rectangular building

1

2

2

3

3

4

4

3

1

2

Wind

Side

Front

back

Table 4 – External-pressure coefficient for flat roof

region

Data from DIN 1055-4, März 2005

PHOENICS for uniform Flow

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

15


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

5.0 Cube-shaped building

5.1 Wind-tunnel measurements

Comparison of the predictions of PHOENICS

with the wind-tunnel measurements of NIST 6371.

Comparisons were made for both shear- and

uniform-flow wind profiles.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

16


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Windkanal, uniform Flow nach NIST6371

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Left: wind-tunnel data for uniform flow according to NIST6371

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

17


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Windkanal, shear Flow nach NIST6371

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Left: wind-tunnel data for shear flow according to NIST6371

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

18


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

5.0 Cube-shaped building

5.2 CFD - calculations

Comparison of the predictions of PHOENICS

with the CFD – calculations of NIST 6371.

Comparisons were made for both shear- and

uniform-flow wind profiles.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

19


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Berechnung, uniform Flow nach NIST6371

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Left: calculation for uniform flow according to NIST6371

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

20


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Berechnung, shear Flow nach NIST6371

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Left: calculation for shear flow according to NIST6371

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

21


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

5.0 Cube-shaped building

5.3 Comparison with DIN 1055-4

Comparison of the calculation results of PHOENICS

with the values given in DIN 1055-4

for uniform wind profile.

.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

22


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Table 3 – External-pressure coefficients for the vertical walls of a rectangular building

Table 4 – Flat-roof coefficients

Values given in DIN 1055-4, March 2005

PHOENICS für uniform Flow 

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

23


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Comparison of Cp;1 and Cp;10 values

Cp;1

Cp:10

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

24


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Cp;10 values

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

25


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Wind

Wind

These images show clearly the dependence of the Cp values on the wind direction!

The values in DIN 1055-4 are given only for +/- 45 degrees.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

26


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

6.0 Slab-shaped building

6.1 Wind-tunnel measurements

Comparison of the results of calculations made by PHOENICS

With wind-tunnel measurements according to NIST 6371,

for both shear- and uniform-flow wind profiles.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

27


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Windkanal, uniform Flow nach AIJ

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Wind-tunnel. Uniform flow according to AIJ

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

28


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Windkanal, shear Flow nach AIJ

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Wind-tunnel. Uniform flow according to AIJ

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

29


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

5.0 Slab-shaped building

5.2 CFD - calculations

Comparison of the calculation results of PHOENICS

with the CFD calculations according to NIST 6371,

for both shear- and uniform-flow wind profiles.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

30


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Berechnung, uniform Flow nach NIST6371

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Left: uniform flow according to NIST6371

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

31


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Berechnung, shear Flow nach NIST6371

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Left: uniform flow according to NIST6371

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

32


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

6.0 Slab-shaped building

6.3 Comparison with DIN 1055-4

Comparison of the calculation results of PHOENICS with the

values given in DIN 1055-4, for uniform-flow wind profile

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

33


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

Values given by DIN 1055-4, März 2005

PHOENICS for uniform Flow

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

34


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

6.0 Summary of the results; and conclusions

There exists a multitude of CFD programs; and within them are to be found many different turbulence models

Therefore to prove the general applicability of CFD for the prediction of wind forces on buildings will not

be possible until there exists a standardised validation process of the kind which VDI 6020, for example,

provides for the simulation of buildings and apparatus.

Nevertheless it would be unwise to disregard a calculation method which has delivered excellent and

verified results in an enormous number and variety of applications.

Indeed, publications from the USA, Japan and Switzerland have shown that CFD calculations of the wind

loads on buildings have given acceptable results.

In the absence of the above-mentioned standardised validation procedure, there remains the possibility of

validating a specific CFD program under precisely-specified boundary conditions. Such a validation must

demonstrate conformity with standards and with wind-tunnel measurements.

These measurements, of course, stand equally in need of validation.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

6.0 Summary of the results; and conclusions (continued)

For buildings of complex form, CFD shows the critical locations instantly and without additional expense.

In wind-tunnel investigations one must know, or guess, these locations beforehand so as to set a limit to

the number of measurement positions.

The picture on pages 18 and 19 show clearly that measuring positions in the guitter region were either

omitted, or were in the wrong positions; whereas the CFFD calculations according to [2] bring to light the

problems presend by sharp edges.

The absence from DIN 1055-4 of the low-pressure zone in the gutter region is probably to be explained

by the desire of the investigator to simplify the measuring procedure.

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

6.0 Summary of the results; and conclusions (continued)

The validation of CHAM‘s PHOENICS program has shown good agreement with the investigations of

NISTIR 6371 and AIJfor the buildings which were studied, i.e. those which could evaluated by

reference to DIN 1055-4.

The agreement with DIN 1055-4, when this is properly interpreted,is of course better, being

within than 15 %

Validation of the CFD program PHOENICS 2008

for the determination of wind loads on buildings

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

37


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Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

6.0 Summary of the results; and conclusions (concluded)

This means that the use of PHOENICS for the present application, namely the Hamburg Central Plaz

Central Plaza, Hamburg, guarantees conformity with DIN 1055-4 März 2005, if the following conditions

are observed:

1. Sufficiently large model with blockage < 5 %.

2. Grid size on the wall surface <= 1m,

by using FINE GRID EMBEDDING

3. Representation of slanting surfaces by way of PARSOL

4. Use of the Large-Eddy-Simulation turbulence model

5. Calculation with varying wind direction (in steps of 15 degrees)

6. Calculation of the wind velocity profile of ground-level category IV

for plane surfaces and/or

7. In order to determine the influence of surrounding buildings, calculation with

a wind-velocity profile of ground-level category II

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

38


Validation of the cfd program phoenics 2008 for the determination of wind loads on buildings39 l.jpg
Validation of the CFD program PHOENICS 2008for the determination of wind loads on buildings

Dipl.-Ing. Frank Zimmermann, Heilbronn, D und Dipl.-Ing. Frank Kanters, Heerlen, NL

References:

[1] Kiefer, H., Windlasten an quaderförmigen Gebäuden in bebauten Gebieten, Dissertation 2003,

Universität Karlsruhe

[2] NISTIR 6371, United States Department of Commerce, Technology Administration,

National Institute of Standards and Technology

Erstellt vom Building and Fire Research Laboratory, Gaithersburg [2]

[3] Numerical Prediction of Wind Loading on Buildings and Structures,

The working group for numerical prediction of wind loading on buildings and structures,

Subcommitee for wind engineering data unit for structural design,

Archtectural Institute of Japan, 1998 [3]

[4] DIN 1055-4, Einwirkungen auf Tragwerke, Teil 4: Windlasten, März 2005

[5] Shah, Kishan, B. and Joel H. Ferziger, A Fluid Mechanicians View of Wind Engineering:

Large Eddy Simulation of Flow Past a Cubic Obstacle, J. Wind Engineering and Industrial

Aerodynamics, Vols. 67 & 88, pp 211 – 224,1997

[6] Gary Easom, Improved Turbulence Models for Computitional Wind Engineering,

Dissertation 2000, University of Nottingham

06.07.2008

Zimmermann-Becker GmbH Beratende Ingenieure TGA

Heilbronn Hamburg Leipzig

39


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