Assessing wind risks for architectural projects with Siemens solutions
ArcAero leverages Simcenter STAR-CCM+ on the cloud for wind engineering projects
ArcAero was formed to bring a distinctive new wind engineering consultancy to the construction and property sectors internationally. Led by established figures within the wind engineering community, all studies are delivered by directors and supported by expert associates, bringing together the best team for every project. Deliberately compact, with a lean, modern mode of operation, ArcAero sells experience and expertise. Together, the company can offer the right technologies without bias, relying only on a focused group of specialists to address critical risks facing clients.https://www.architecturalaero.com/
- London, United Kingdom
- Simcenter Products, Simcenter STAR-CCM+
Building for the future
Many of us have walked past skyscrapers and stadiums and been swept away by the sheer size, scale and grandeur of these engineering feats. But almost none of us have been swept away by strong gusts of wind as we take in these gigantic structures. Why? Because wind engineering done correctly keeps the force of the wind safely at bay. Addressing wind microclimate is fundamentally about risk management and capitalizing on opportunities to improve design and – where possible – reduce costs for clients.
ArcAero’s story as a wind engineering consultancy began only a few years ago, but today the small London-based firm has taken on some of the most difficult and complex construction projects around the world. The company’s engineers have worked on a range of impressive development projects including the London 2012 Olympic Park, Manhattan Loft Gardens in London, Mercedes Benz Stadium in Atlanta and London’s Gatwick Airport.
The project team at ArcAero is purposefully kept small with the goal of completing projects in a lean and efficient manner. The team has a wealth of industry experience and draws on a range of technologies such as wind tunnels and computational fluid dynamics (CFD) simulation to provide an unbiased risk assessment to their clients.
A fine balance between safety and aesthetics
This small company faces the same challenges as some of the industry’s larger and more traditional players. In recent years, ArcAero has increasingly relied on CFD simulation to supplement physical testing. Insight gained from CFD simulation is becoming a critical factor in helping its clients understand the challenges they face in safeguarding pedestrian comfort in the built environment.
These safety challenges are significant; even more so given the high cost of these developments, some of which exceed hundreds of millions of dollars. Architects working on these developments will give thoughtful and serious consideration to aesthetics and space planning, but this does not negate the need for expertise from a consultancy such as ArcAero during the planning and design process. For example, a plush outdoor seating area with excellent views is of little use if occupants of that space are frequently hit by strong gusts of wind as a result of poor wind engineering.
While not impossible, combining safety and aesthetics can be a difficult challenge. ArcAero’s goal is to enable clients to design and deliver architectural structures that are aesthetically pleasing, comfortable and safe.
From a technical point of view, the impact of wind conditions is difficult to quantify due to the range of possible weather conditions as well as accounting for the effects of the surrounding terrain and buildings. Wind tunnel testing is a traditional method for assessing comfort and safety; however, even for more modest structures this can be very costly and time consuming. To overcome this challenge, ArcAero selected CFD solution Simcenter™ STAR-CCM+™ software, which is part of the Xcelerator™ portfolio, the comprehensive and integrated portfolio of software and services from Siemens Digital Industries Software. ArcAero found that it offered several capabilities such as high fidelity, fast turnaround and powerful workflow automation in line with their requirements.
Preparing complex CAD geometries within a day
One of the initial steps in the CFD process is to prepare the geometry for preprocessing. Consultancies such as ArcAero work with their clients and are often provided geometry in a wide range of computer-aided design (CAD) formats. These files are obtained from multiple sources and serve many purposes other than virtual wind simulations. As a result, these files are often unsuitable for direct use in CFD simulations. In some cases, CAD data may be incomplete or contain errors such as gaps or self-intersecting surfaces. The files can be architectural model visualizations, engineering structural CAD, or survey data for the surrounding areas.
Preparing CAD geometry for simulation has historically been a time-consuming process. It often takes several days to repair errors in the models and extract enough detail for the development itself as well as buildings, other man-made structures, terrain and even trees in surrounding areas.
ArcAero takes advantage of the built-in surface repair tool in Simcenter STAR-CCM+ to resolve errors in CAD data with just a few clicks. The engineering time to clean up the most complex geometry can be reduced to a day, rather than weeks. Being able to do this reliably without manual intervention is critical to speeding up the geometry preparation step, delivering more value to their clients with their solutions and expertise.
Increasing productivity with automation
As a consultancy working on high-profile projects, ArcAero’s focus is constantly with their clients and finding ways to deliver on their high expectations. The team believes the route for client satisfaction is through iteration and optimization; they are continuously evaluating ways to positively impact projects.
ArcAero has many options they can recommend to mitigate undesirable wind conditions, but identifying the best course of action means the company must explore the effect of a large number of possible scenarios. To evaluate these options ArcAero has created an automated end-to-end work-flow for CFD analysis.
“Workflow automation using Simcenter STAR-CCM+ is key for us to create a robust and repeatable process with minimal scope for human error,” says Joe Osman, director at ArcAero. “We have developed a completely automated process with Simcenter STAR-CCM+. We spend minimal engineering time on the interface, which has allowed us to focus on results rather than CFD and the process behind it.”
Once the CAD data has been prepared, the engineering time required to go from CAD to solution is truly minimal. With the process the company has developed using Java automation, all of the remaining simulation setups and preprocessing are done automatically and most models are ready to run within 10 minutes.
An example of how ArcAero has leveraged automation was on a project for Lower Essex Square in Birmingham, U.K. Initially, a CFD model was built and run quickly to provide early predictions of any hotspots the development was likely to cause. These simulations were verified in the 10-by-five feet wind tunnel at Imperial College in London, with the CFD simulation then leveraged to visualize problematic wind patterns and help explore design strategies to alleviate the various hotspots. Finally, using the automated process, ArcAero performs a number of simulations in succession, iterating towards a final solution which then goes to the wind tunnel for validation. This approach ultimately resulted in spaces that were functional and accessible without risks to pedestrians.
Reducing simulation run time from days to just 30 minutes
Early on, ArcAero had a choice to make about compute resources: purchase a high-performance computer (HPC) outright or shift all workloads to the cloud. The decision was easy; the cloud ticked all the boxes when it came to flexibility, performance and cost. The latter was especially important because, as a small business, avoiding large upfront capital costs and having a more stable balance sheet made financial sense.
“With varying demand in project workloads, cloud computing offers a cost-effective and flexible option in comparison to owning on-premise hardware,” says Osman.
Flexibility to scale up or scale down compute resources is critical for consultancies like ArcAero since project demands can vary from week to week. “We can use thousands of cores on one day and none for the rest of the week,” says Osman. “Running Simcenter STAR-CCM+ on the Gompute cloud platform, we are able to get results back within 30 minutes, compared to two days if we were to run locally.”
“Cloud enables our company to handle large fluctuations in capacity as we scale up and pay for what we use, which perfectly suits our highly variable throughput,” says Robin Stanfield, director at ArcAero.
In the end, ArcAero chose the Gompute cloud platform, and the company hasn’t looked back on its decision. In addition to offering comprehensive customer support, Gompute enables seamless customization and integration of Simcenter STAR-CCM+ scripts to tie in with the entire automation process, providing a higher level of control for the team in the cases submitted and delivering a robust process.
ArcAero can perform simulations quickly since Simcenter STAR-CCM+ is designed for parallelization. Coupling this with the flexible licensing such as Power on Demand (PoD), this pay-as-you-go approach aligns perfectly with running CFD simulations in the cloud. “Cloud hardware allows us to get the most of our licensing costs,” says Stanfield. “We can run virtually unlimited simulations simultaneously. This reduces the turnaround time and allows us to do more thorough exploration of the design space and help our customers to a better solution.”
Looking out for the public
Although the majority of projects ArcAero works on are on behalf of developers, occasionally the company is invited to work on a unique request. For example, the London Borough of Tower Hamlets called on ArcAero to provide wind engineering industry expertise to a planning inquiry for the former Westferry Printworks site on the Isle of Dogs, where a planning dispute unfolded following the closure of the printworks located on the north side of Millwall Outer Dock in 2012.
The project sought to determine the impact of the development on the environment for sailing on the adjacent Millwall Outer Dock. The local sailing club shared the concerns about the likely wind impact, arguing that the developer’s proposal would severely and negatively alter wind conditions for sailing in the vicinity. The response from developers, based on advice from their experts and wind tunnel data, was that the wind quality, derived using average wind speed and wind direction, was within acceptable limits.
Taking an unbiased view, ArcAero performed a series of CFD predictions using Simcenter STAR-CCM+ to demonstrate that, irrespective of the findings that the averaged data produced, there were likely to be additional impacts due to transient phenomena such as turbulence, recirculating eddies and downdrafts. Without an adequate understanding of these effects, they argued, it was not possible to conclude that acceptable sailing conditions would remain post-development. ArcAero used CFD to highlight areas that showed a significant risk of wind recirculation and regions of high turbulence.
ArcAero continues to successfully provide insight and solutions to their clients, Osman believes that CFD will continue to grow, becoming the more dominant analysis method in environmental wind engineering, and that the cloud will be critical in enabling companies like his to meet deadlines and remain agile in this competitive industry. The company’s use of simulation with Simcenter STAR-CCM+ has played a pivotal role in understanding the impact that large-scale building projects have on the local wind microclimate. CFD analysis enables ArcAero to identify and recommend changes that have minimal impact on aesthetics while providing a significantly improved experience for pedestrians. Running simulations on Gompute’s cloud platform and using Power on Demand licensing with Simcenter STAR-CCM+, ArcAero can flex and adapt compute resources based on project demands to meet customer project deadlines.