The saying “nature abhors a vacuum” is attributed to Aristotle who mused on the nature of voids in Book IV of his lectures on physics. Unlike Aristotle and Mother Nature, refrigeration technicians ought to have a healthy love of vacua
Happy Birthday, Mr. Rankine
When the Fourth of July celebrations are fading into the morning after the night before, please take a moment to raise a glass to Professor William Rankine on the occasion of his 200th birthday. I had hoped to be leading
Working From Home
I’m writing this from my “home office,” also known as the attic, in the midst of the pandemic lockdown that has affected so much of the world in the last few months. I hope that by the time you are
Getting the Best From Zeotropes
The two most recent columns in this series may have seemed unnecessarily gloomy about zeotropic refrigerant blends. However, like most things in life that have unusual features, there are ways in which their oddities can be used to advantage. A
Mixed Messages on Mixed Refrigerants
The idea of mixing two fluorocarbons to provide a refrigerant that behaved like a single fluid but with beneficial properties was commercialized in the 1950s with the introduction of R-500, R-501 and R-502. ASHRAE Standard 34, which was originally published
Why Zeotropes Upset Me
For many, many years I’ve found the word “zeotrope” disconcerting and upsetting. I didn’t know why; it just irked me. When I was in high school studying chemistry, we learned about azeotropes, unusual mixtures of liquids, which didn’t distill when
The Art of Compromise
When I was a small kid, whenever there was a discussion or disagreement about what was happening, my mother would say “Well, we will compromise and do it my way.” It was years before I learned that this is not
Looking Back and Forward
January is a good time for taking stock, looking back over what’s been achieved and looking forward to what is to come. 2020 has a particular significance because it is the year that the Montreal Protocol restriction on the use
Still Frozen?
Last month’s column considered how the rapid growth of urban populations in the nineteenth century was the catalyst for the growth of the mechanical refrigeration industry. It is doubtful that those pioneers could have foreseen the diversity of applications for
The Frozen Water Trade
In 1800 the global population was about 1 billion people and by 1900 it had grown to 1.6 billion. In North America the largest city throughout that time, New York City, rose from 60,000 inhabitants to about 4 million. Over