December 6, 2019
Urban Modeling: From 3D Scanning To Numerical Wind Simulation
3D Laser Scanning have been applied to scan buildings in the last years. But the 3D laser building scanning is only one side of the work. The output of the 3D laser scanning is usually a point cloud. In order to use the file of the 3D laser scanning this point cloud has to be transformed into a closed surface or volume model. In the case of buildings and monuments this can be very complicated, leading to ten thousand an more surfaces. Here it is also important to decide on what level of detail will have an impact on the wind simulation. Then the numerical grid for the wind simulation has to be generated and the flow around the buildings or monuments solved numerically. Finally, these results have to be analyzed to extract the relevant information for the given research goal.
In this presentation two complete case studies will be presented. The first one is the laser building scanning and the numerical wind simulation around the Roebuck Hall Residence (RR), located on the University College Dublin’s campus. Numerous localities have attempted to harness wind resources for electricity generation using roof-integrated wind turbines (RIWTs). Disappointingly, the monitored performance of RIWTs is typically only 5%-11% of the designed capacity. The current study explores the extent to which this deficit is due to poor RIWT placement in the absence of precise wind power information for installation sites and how this may be countered with terrestrial laser scanning based models for complex structures and with numerical wind simulation.
The second study is the wind simulation around the Prince Consort Albert memorial in Coburg, Germany. This memorial was laser scanned and a numerical wind simulation around it was performed. In this work the challenge was to scan the memorial at a level of detail to resolve properly the face and the wrinkles of his garment. Having the proper resolution, also the right grid resolution to simulate the wind around the monument had to be found. This procedure and the comparative results for different resolutions will be presented.
Finally, examples of experimental wind flow visualization around models of buildings and how they can be used to better understand the impact of the shape of a building on the flow around it will be shown.
Dr. Debra Laefer is a Professor in the Department of Civil and Urban Engineering in the Tandon School of Engineering, and Professor of Urban Informatics and Director of Citizen Science in the Center for Urban Science + Progress at New York University .
With degrees from the University of Illinois Urbana-Champaign (MS, PhD), NYU (MEng), and Columbia University (BS, BA), Prof. Debra Laefer has a wide-ranging background spanning from geotechnical and structural engineering to art history and historic preservation. Not surprisingly, Prof. Laefer’s work often stands at the cross-roads of technology creation and community values such as devising technical solutions for protecting architecturally significant buildings from sub-surface construction. As the density of her aerial remote sensing datasets continues to grow exponentially with time, Prof. Laefer and her Urban Modeling Group must help pioneer computationally efficient storage, querying, and visualization strategies that both harness distributed computing-based solutions and bridge the gap between data availability and its usability for the engineering community.
In her decade and a half as a faculty member in both the US and Europe, Prof. Laefer has served as the principal investigator for grants from a wide range of sponsors including the National Science Foundation, the US Federal Highway Administration, the National Endowment for the Arts, the National Endowment for the Humanities, Science Foundation Ireland, and the European Research Council (including a €1.5 million single investigator award from the flagship ERC program for which she is the only civil engineer to have been funded in Ireland).
Prof. Laefer has authored over 160 peer reviewed publications, been awarded 4 patents, and has supervised 15 doctoral and 20 Masters theses. Among many honors from IEEE, ISPRS, and other professional societies, the most notable is perhaps the 2016 commissioning and hanging of her portrait by the Royal Irish Academy as one of eight researchers selected to celebrate Irish women in science and engineering. She currently helps form national research programs and policies in her governmental appointment to the Irish Research Council (2016-2020).
Philipp Epple is a visiting scholar at CUSP. He has been a full Professor for fluid mechanics and turbomachinery at the department of mechanical engineering of the Coburg University of applied sciences in Germany since 2011. He teaches classes of introductory and advanced fluid mechanics, classes of introductory and advanced turbomachinery, numerical fluid mechanics (CFD), thermodynamics, heat transfer, wind energy and related fields. He has been the head of the group of turbomachinery and process fluid dynamics at the Institute of Fluid Mechanics of the University of Erlangen for several years. He received his doctoral degree in mechanical engineering with honours from the University of Erlangen. He has worked in the design, development and CFD computation of turbomachines, having done uncounted CFD computations for a large variety of machines, like for example fans, ranging from some centimetres to over two meters in diameter, wind turbines, also an high velocity ICE train, big waste water and small blood pumps. He has also done simulations of building aerodynamics and of small roof top wind turbines. He has built more than 15 test rigs for turbomachinery and performed measurements on more than 300 turbomachines. He worked on over 40 industry projects in the field of turbomachines and fluid mechanics. He has supervised about 100 master and several PhD theses. He has more than 100 publications in international journals and peer reviewed conferences. He is a member of the ASME, AIAA and of the VDI. He is also an associate editor of the ASME Journal of Fluids Engineering as well as a member of the Executive Committee of the Fluids Engineering Division of the ASME (American Society of Mechanical Engineers).