Taylor Oetelaar PhD, Mechanical Designer AP Dynamics Inc.
Thanks to Taylor Oetelaar’s unique passion for history, architecture and computational fluid dynamics, we can now imagine what it would be like to lounge in a third-century Roman bath that was heated by multiple fires below a suspended floor.
by Wendy Glauser, University Affairs December 3, 2014
One of many findings of Dr. Oetelaar’s research, for instance, is that the air temperature would have been akin to a modern sauna, even in the winter. His digital reconstruction of the Baths of Caracalla is now part of a high-tech, 3-D model of ancient Rome called “Rome Reborn,” which is being exhibited in museums around the world. But his research applies to the present day, too. “Seeing how the Romans incorporated their systems might give modern engineers ideas for the next innovation,” says Dr. Oetelaar.
His PhD supervisor, engineering professor David Wood, says it’s not only Dr. Oetelaar’s “extraordinary intelligence” as an engineer that impresses him but also his “very strong knowledge about the architectural issues and societal issues.” (Dr. Oetelaar writes in his dissertation there were almost 900 baths in Rome, which he compares to the 102 Starbucks in Calgary.)
Source University of Calgary
| Looking forward to engineering the Roman Baths |
By Jane Chamberlin, Schulich Engineer, Mechanical & Manufacturing May 15, 2013
| How to study the past with an eye on the future |
It’s two in the afternoon and you’ve had a long, tiring day at the Forum. Your friend Lucius is waiting, so you hurry past the amphitheatre and enter the building that towers over the street. You shed your robe but keep your sandals on so the tiles don’t scald your feet. You forego your usual wrestling match and hurry past the jugglers, philosophers and hair-pluckers, then grab some pickled olives from a vendor. Ducking through a small door into the steamy caldarium, you spot Marcus in one of the pools. When you slip into the water, it’s as if the day never happened.
A place to unwind, chat, exercise and eat – an ancient Roman bath was like a cross between a coffee shop and a gym. But with 100 percent humidity. The baths were enormous – conglomerations of rooms with hot pools, warm pools, cool pools and swimming pools, plus conversation areas, exercise courts and change rooms. The building could be up to 2.4 hectares – as big as four football fields. Including the gardens, a bath complex could be up to 9 hectares altogether.
The study of the Roman baths is ongoing and riddled with knowledge gaps, because nearly all the baths – and there were over 900 in Rome alone – are now in ruins or have completely disappeared. “It’s akin to trying to complete a puzzle with half the pieces and the box missing,” says Taylor Oetelaar, a recent Schulich School PhD graduate in mechanical and manufacturing engineering. In his dissertation he puzzled out some of the thermodynamic mysteries of the baths by combining two of his passions – classical archaeology and engineering.
Over the years, scholars have wondered whether the secret to temperature control lay in the doorways and windows of the buildings. Were the windows glazed? Why were the doorways so narrow? What were the doors made of?
| Viewing ancient systems through a modern lens |
In his trans-disciplinary research, funded by the Natural Sciences and Engineering Research Council of Canada and the Alberta Ingenuity Fund, Oetelaar analyzes the heating system within ancient Roman baths. Oetelaar’s process involved the use of computational fluid dynamics or CFD, which can be simply defined as a numerical methodology that helps you predict how a fluid will behave in a given scenario. His analysis focused on the caldaria, or rooms with hot pools, of two different baths – the Baths of Caracalla in Rome, and a replica of a smaller one created for the television series, Nova.
He set out to provide an enhanced understanding of the thermal environment inside those rooms, examining the temperature distribution and air velocities in the bathing areas.To begin his investigation, Oetelaar devised a series of experiments to measure the heat input into the caldaria from the radiant heating system – the hypocaust. He built a system with a similar thermodynamic process as those manned by slaves in ancient Roman baths. From the furnace, hot air would circulate between a false floor and the foundation floor and through terra cotta tubuli – pipe-like structures that ran up the walls – and out a chimney.
This system is not unlike modern-day radiation slab cooling, which uses convective heat transfer for heating, ventilation, and air-conditioning (HVAC) systems.Using materials that closely replicated the hypocaust construction, Oetelaar carried out experiments that were unique in the HVAC world because they examined how air heats a surface, not how a surface heats the air. In the end, Oetelaar was able to accurately calculate the coefficient relating the heat input into the room from the radiant heating system to the exhaust gas temperature.
To fully analyze the baths’ thermal environment, Oetelaar created intricate 2- and 3-D CFD simulations of Roman baths and a full digital reconstruction of the Baths of Caracalla. The models offer great insight into the heating challenges in those long-ago rooms, which involved finding a delicate balance between hot, too hot and too cool. Average temperatures in the caldarium could soar as high as 47°C, but in winter it was a matter of keeping the water warm enough. So finding reliable ways to distribute heat was crucial.
| Re-imagining the Roman bath |
Over the years, scholars have wondered whether the secret to temperature control lay in the doorways and windows of the buildings. Were the windows glazed? Why were the doorways so narrow? What were the doors made of? Through his CFD analyses and 2-D assessments, Oetelaar has made significant headway in answering these questions. For example, he’s found evidence to suggest that the caldarium windows were indeed glazed, in order to maintain reasonable bathing temperatures.
In fact, much of Oetelaar’s research will further the discourse on Roman baths, says Dr. Lisa Hughes, associate professor in the University of Calgary’s department of Greek and Roman studies, and one of Oetelaar’s PhD committee members. “Up until this point,” says Hughes, “we only had snippets of ideas from the ancient literary sources and other studies of what the bathing environment was like. Taylor Oetelaar’s research will be useful in terms of adding depth to our understanding of the overall bathing experience and of how architectural features such as windows and doorways contributed to achieving a suitable environment.”
This new knowledge of Roman baths impacts the engineering field as well. “My research improves our understanding of large volume HVAC processes,” says Oetelaar, “and hopefully will lead to improvements there. It also adds to our knowledge of heat transfer through the investigation of a case of warm air heating a channel.”
Adding to the conversation in one’s discipline – or disciplines, in Oetelaar’s case – is a tremendous achievement. But if you ask him about the moment that took his breath away during the project, he will probably tell you a story about a city where crumbling stone walls can be imagined into god-sized buildings with water that soothes. Two years into his research, Oetelaar went behind the scenes at the Baths of Caracalla in Rome, an experience he will never forget. “In a word, it was mind-blowing,” says Oetelaar. “I was extremely lucky and got to take measurements of features that are off limits to the general public, thanks to Professoressa M. Piranomonte and the Soprintendenza Archeologica di Roma. Combine all this with the sights, food, and smells of the Eternal City, and it was an amazing trip.”
That’s what happens when you have the good fortune to blend two of your passions into a project that looks backward – with a forward-thinking mindset.
Source University of Calgary
| References |
Reconstructing the Baths of Caracalla, Taylor Oetelaar, Digital Applications in Archaeology and Cultural Heritage, Volume 1, Issue 2, 2014, Pages 45–54
Determination of the Convective Heat Transfer Coefficient of Hot Air Rising Through Terracotta Flues, Taylor Oetelaar, Clifton Johnston, Transactions – Canadian Society for Mechanical Engineering 09/2012; 36(4):413-428
A computational investigation of a room heated by subcutaneous convection—A case study of a replica Roman bath, Taylor Oetelaar, Clifton Johnston, David Wood, Lisa Hughes, John Humphre. Energy and Buildings 08/2013; 63:59–66. DOI:10.1016/j.enbuild.2013.03.049
Also see
Taylor Oetelaar, Engineering PhD: Student of Rome. Seeker of challenges University of Calgary
Ancient Rome Reconstructed in 3D in 3dprint.com
