PHOENICS User Conference 2004

1. PHOENICS User Conference 2004 “Applying CFD to Environmental Flows” Eric Jal Connell Wagner, Melbourne, Australia 3-5 May 2004 - Melbourne, Australia

2. Introduction • Environmental consequences within the built environment are becoming a crucial issue in engineering project developments • Increasingly common to use CFD in the design process to assess and optimise environmental flow impacts relating to:- • pedestrian comfort and safety • exhaust emissions • airborne dispersion • snow deposition

3. Project Case Studies • PHOENICS CFD code has been used • TECPLOT used for results visualisation • Several case studies will be presented:- • City Square - Melbourne, Australia • Holdfast Shores - Adelaide, Australia • Urban City Planning - Wellington, NZ • Perisher Valley Resort - NSW, Australia • City Link Stack - Melbourne, Australia • Holden Sand Bins - Melbourne, Australia

4. Case Study - City Square City Square - Melbourne, Australia

5. City Square - Design Scope • The Melbourne CBD City Square precinct incorporates an underground car park • Due to architectural constraints the exhaust stack is through a street level cafe • Concerns were raised of the discharge upon café patrons and upon adjacent buildings (hotel with exposed balconies) • CFD study conducted to assess effect of stack discharge for different wind condition • Provide optimised stack solution

6. City Square - Design Analysis Exhaust Discharge : 3m/s Southerly Wind (22oC Day)

7. City Square - Design Analysis Exhaust Discharge : 3.5m/s Westerly Wind (22oC Day)

8. Case Study - Holdfast Shores Holdfast Shores - Adelaide, Australia

9. Holdfast Shores - Design Scope • Multi-use precinct development situated at Glenelg on Adelaide’s coastal strip • Pedestrian comfort and safety concerns on a footbridge due to it’s position (“wind-gully”) • CFD modelling analysis was conducted • Assessment performed of various proposed ‘wind-break’ structures (with key aesthetic feature must have minimal visual impact)

10. Holdfast Shores - Design Analysis Environmental Wind Flow : 9.25m/s Westerly Wind

11. Case Study - Urban City Planning Urban City Planning - Wellington, New Zealand

12. Urban City Planning - Design Scope • Pedestrian comfort and safety aspects are a prominent issue for urban city planning • In Wellington specific rules apply as proviso for permitted building developments (over four storeys high) • Property developers and designers must demonstrate no adverse effects on the local wind conditions around the building vicinity • Establish that CFD can be a useful tool

13. Urban City Planning - Design Analysis Environmental Wind Flow : 21m/s Northerly Wind

14. Case Study - Perisher Valley Resort Perisher Valley Resort - NSW, Australia

15. Perisher Valley Resort - Design Scope • Issues were raised during Environmental Impact Statement (EIS) concerning likely snow drifting around redeveloped resort • Two configurations were analysed with CFD to establish snow deposition around the buildings and pedestrian concourse areas • A two-phase CFD model was developed • The study demonstrated that CFD could be utilised as a practical tool for architectural planning purposes

16. Perisher Valley Resort - Design Analysis Environmental Wind Flow : 25km/hr WSW Wind

17. Case Study - City Link Burnley Stack City Link Burnley Stack - Melbourne, Australia

18. City Link Burnley Stack - Design Scope • Emissions from the vent stacks need to be monitored (EPA policy) to ensure pollutant concentrations are within statutory levels • During commissioning it was found that the discharge flow within the exhaust stack was non-uniform and as a consequence the flow could not be sampled and measured • CFD study was undertaken to establish flow characteristics and determine a satisfactory solution to overcome the problem

19. City Link Stack - Design Analysis Stack Exhaust : As Built Configuration

20. City Link Stack - Design Analysis Stack Exhaust : Modified Shaft Geometry Configuration

21. Case Study - Fugitive Emissions Fugitive Emissions : Industrial Sand Storage Bins

22. Conclusions • Project case studies have shown the use of CFD for assessing and optimising solutions related to environmental flows • Issues relating to exhaust emissions, snow deposition, airborne dispersion, pedestrian comfort and safety can be addressed with CFD and can also provide cost benefits • Anticipated that CFD will be a useful tool and essential aid for urban developers, architectural designers and environmental planners for the built environment design

23. Presentation End a Thankyou!