Buckminster Fuller’s Chilling Domes: the physics
I have just released a new comic entitled Buckminster Fuller’s Chilling Domes.
It is my first comic about one of my true heroes, Buckminster Fuller. I hope to draw many more comics about Bucky throughout my career as a cartoonist.
If you haven’t already done so, please now read my comic Buckminster Fuller’s Chilling Domes, which I will refer to in the rest of this essay.
A forgotten phenomenon
Bucky Fuller was a true polymath, responsible for many, many different ideas and inventions throughout his career.
When people reflect back on Bucky’s career, he is primarily remembered for inventing the geodesic dome: the most structurally-strong, resource-efficient way to enclose a space with a physical structure. Bucky is also remembered for other inventions such as his three-wheeled Dymaxion Vehicle, as well as his prototyped Dymaxion House, which was a spiritual successor to the Dymaxion Deployment Unit that never entered mass-production.
Yet instead of focusing on those well-known Bucky inventions, I decided to focus on one of his “forgotten” discoveries: the self-chilling, zero-energy, passively-cooled dome home.
Why I chose to draw about this phenomenon in particular
The reason I drew a comic about Buckminster Fuller’s self-chilling domes is because he personally experienced the phenomenon while constructing the Dymaxion Deployment Unit (DDU) in Kansas during summer 1940.
It was something that physically existed in the real world.
Instead, I chose to cover a phenomenon that Bucky Fuller personally experienced in the flesh, along with the other men on the construction site such as Butler Manufacturing president Emanuel E. Norquist.
My references for the Chilling Domes phenomenon
I first learnt about the phenomenon through the following three books:
- Buckminster Fuller’s Universe by L. Steven Sieden (1989; pp208-9)
- BuckyWorks by J. Baldwin (1996; p36 & pp114-17)
- Critical Path by R. Buckminster Fuller (1982; p211)
However, the granddaddy of all sources seems to be the lecture that Buckminster Fuller gave in Philadelphia on 30 January 1975. This was session 10 of his Everything I Know lecture series, in which he attempted to communicate his entire life’s work in spoken format. The series of 12 lectures ended up spanning 42 hours(!)
The lecture exists as text transcript. (Ctrl+F to the phrase “Now, it was August, 1940”, where he begins describing what happened inside the grain silo.).
It also exists as a video, which is probably the best way to experience it, due to Bucky’s extensive use of ‘talking with his hands’ to demonstrate convection currents.
If you want to hear the entire story about that summer day in Kansas, watch the video from clip #142 to #152 (roughly 13 minutes total).
If you don’t have much time, the central part of the story, with him describing the physics is from #145 to #149 (roughly 6 minutes total).
A multitude of terminology
There are a lot of terms associated with this phenomenon. I will mention some of them here:
- The phenomenon is specifically referred to as either “chilling domes” or “chilling machines” by the 3 books by Sieden, Baldwin and Fuller. Others have described the downward air current as a “reverse chimney effect“.
- Broadly speaking, the phenomenon fits into the building design approach of passive cooling, since it is a way that the building sheds heat automatically, without the need for active cooling such as electrically-powered air conditioners.
- Buckminster Fuller himself described the underlying phenomenon as, “Bernoulli’s principle”, with other writers calling it “the Bernoulli effect” or “the venturi effect”.
Unfortunately, as I will soon describe, the explanations of the physics behind this chilling dome phenomenon is often patchy.
Dodgy physics, dodgy explanations
The three books do a good job of describing the airflow phenomenon, but they do a bad job of explaining the phenomenon.
Most explanations stem from Bucky’s own assertion that Bernoulli’s principle is the underlying phenomenon driving the air currents.
Wanting to express the concept as accurately as possible in my comic, I sought input from a physicist friend, Chris Weekes.
Chris helped me to discard some of the dodgy explanations which contravened the laws of physics. For example, Sieden (1989) stated that the air entering the small inlet vent was “compressed” as it entered.
By contrast Chris and I do not believe that the air molecules compressed as they entered the dome through the top vent. This is because air does not have a tendency to move from low-pressure to high-pressure.
Instead of compressing, we think that the explanation is that the air molecules accelerated when they entered the top vent, converting the thermal energy of the warm ambient air into kinetic energy. This is more in line with Baldwin (1996)’s explanation.
However, all writers (Sieden, Baldwin and Fuller) state the Bernoulli principle is the best way to explain the phenomenon. Instead, Chris and I think that acceleration under the principle of conservation of energy; as well as adiabatic expansion, are the best ways to explain it. The Bernoulli principle is involved in what is going on, but there are more generalised ways to explain the phenomenon using more generalised conservation of energy principles, following the first law of thermodynamics.
Why is this chilling dome phenomenon unheard of?
As I publish this comic, it is August 2015. It is now exactly 75 years after Buckminster Fuller described the “chilling dome” effect in Kansas City when building the Dymaxion Deployment Unit prototype in 1940.
Yet, today, as I search the web for information, I can only find one Bucky-related web page dedicated to this phenomenon. And I cannot find reference to the “reverse chimney effect” phenomenon in any of the ‘green architecture’ or ‘passive solar building design’ resources that I have checked.
So why has this principle been ignored?
This is a genuine question that I am raising, as I am keen to know the limitations and drawbacks of the phenomenon.
Possible explanation #1: it is disbelieved, and therefore ignored
Take another look at Buckminster Fuller’s Everything I Know lecture 10, specifically clip #150.
In the clip #150 video Bucky admits that the phenomenon is counter-intuitive, as common sense suggests that warm air would exit through the vent in the top of a dome on a warm summer day.
Bucky described householders moving into geodesic dome homes, and installing electric exhaust fans at the top of their domes, attempting to blow the warm out out of the top of the dome. He describes this as being an energy-wasting arm wrestle against the passive forces created by the structure’s natural air flow.
Bucky also says that “air conditioner salesmen are better than I am” in convincing householders to install an electric air conditioning system. He suggests that home occupants are unwilling to risk being caught in the middle of a heat wave, relying on passive cooling methods. So they install active cooling (air conditioners) for peace of mind.
Possible explanation #2: it does work, but is impossible to employ in some cases
The phenomenon, from my understanding, seems to work due to the heat rising from the sunbaked exterior walls of the structure.
Therefore, it would be difficult, perhaps impossible to create the effect if the house was not in direct sunshine. For example, if the house was surrounded by taller buildings, or tall trees that shaded the house. In clip 151, Bucky admits that the phenomenon does not work at night time. Perhaps it also does not work in the shade.
Possible explanation #3: it does work, but operates contrary to the way that people normally use their houses
It is possible that the phenomenon works most effectively if the interior of the house is sheltered from lateral breezes created by opening windows on the walls of the houses.
Building occupants usually have a psychological tendency to cool their living areas by opening doors and windows on the side walls of their house, and creating lateral breezes.
It could be that these lateral breezes interfere with the vertical airflow that this “reverse chimney effect” relies on.
(As a side note, the apertures for cooling module of this nifty sustainable building design workshop suggests that householders can produce a mini version of adiabatic cooling from the lateral breeze that flows through a house. You just need to strategically open your windows so that the windows on the windward side have a smaller size than the windows on the leeward side. If the prevailing wind is strong enough, air will be sucked through your house from the low pressure area on the leeward side of your house. Here is the diagram from that web page, though I can’t personally vouch for it working:)
Possible explanation #4: it does work, but there are superior passive cooling strategies
The phenomenon is driven by solar energy creating thermal updrafts from walls and paved areas surrounding a house.
Therefore, it cold be that other passive cooling strategies hinder Bucky’s effect coming to full fruition. For example, if you installed a green wall or similar external shading systems on the exterior of your building, the solar gain would be blocked or diminished.
Possible explanation #5: it doesn’t work at all
This is another explanation to consider: Bucky was simply telling a lie. Though I personally presume that Buckminster Fuller was telling the truth, especially since he lists specific witnesses such as Butler Manufacturing president Emanuel E. Norquist.
Nevertheless, I did discover this Google Groups forum that claims to have debunked the phenomenon. A user (‘KK’) has posted a message claiming that they have busted the idea of a chilling dome by constructing a scale model that could not reproduce the downward air current through a top vent. Unfortunately the relevant video that the user refers to has be removed from YouTube, so we can no longer see the footage.
Time for more research and development
As I mentioned towards the start of this article, there is currently almost zero information currently on the web recommending the “reverse chimney effect” as an effective passive cooling option.
Yet, if it does work, it seems like it would be an energy-saving technology that would be able to slash energy bills and fossil fuel consumption. Imagine if, for example, server farms could be housed in buildings designed to passively cool using this reverse chimney effect / adiabatic expansion. I’m sure that supplemental energy would still be needed to ensure that the servers are always chilled to the appropriate temperature. But perhaps passive airflow could perform the brunt of the work without the need for energy. This is just a thought bubble on my part.
I encourage builders, designers, and home owners to test this phenomenon and share the results with the internet at large. Perhaps via the ‘comments’ section below.
A call for patrons
Did you enjoy your reading experience? Did I teach you something new about Buckminster Fuller’s chilling dome discovery?
If so, please become a recurring monthly supporter via crowdfundstu.com. I spent roughly 120 hours on this comic, as well as the associated research, fact-checking, physics-checking and blog post-writing.