Published Date 7/26/18 7:00 AM
Every other summer since 1972 a community of brilliant minds comprised of academic researchers, students, and industry professionals gather in central Indiana, USA to share their findings on various topics that push the limits of current technologies in the built environment. This past week under the backdrop of a scorching July heatwave the Purdue University held its 24th Compressor Engineering Conference, 17th Refrigeration & Air Conditioning Conference and the 5th High Performance Building Conference. These three simultaneous conferences are hosted by the Ray W. Herrick Laboratories and the Center for High Performance Buildings at the Purdue University, enabling the HVAC/R industry for the over four decades to continually innovate and inspire the next generation of engineers.
Unlike any other time in our species history has this work been so critically important, a race against time is underway to sustainably preserve and improve quality of life for future generations. Global scientific consensus paints a bleak apocalyptic like future world; an anthropogenic result from decades of haphazardly consuming finite resources of fossil fuels, driven by short-sighted goals of immediate economic growth without concern for environmental impacts. A 2015 report from the International Institute of Refrigeration, found there are already in existence 3 billion refrigeration and air-conditioning systems globally, directly accounting for 17% of global electrical demand and 8% of greenhouse gases. Global populations are projected to soar past 11 billion by the end of this century, and as developing nations increase their GDP/capita luxury items like air conditioning and refrigeration with increase as well, an additional 1.6 billion AC units by 2050 is predicted. The energy consumed by these additional ACs will strain fragile infrastructure, requiring more generation plants to be built which if used with fossil fuels could drastically increase greenhouse gas emissions pushing average global temperatures past the tipping point. There is the silver lining that already underway is a global phasedown of HFC refrigerants, those with Fluorine atoms which are far more harmful than CO2, and will avoid a 0.5C rise in temperature by 2100. This activity pushes the HVAC/R community to join together to create, innovate, and design to push current technological knowledge towards another break through.
This was my second time attending the Purdue conferences, and immediately after the closing of the 2016 conferences I blocked my calendar to ensure I would be able to participate again. Over the past two years I have taken what I heard and earnestly sought out new knowledge to put into practice, and inspire others to do the same in order to create a more efficient and sustainable future. My expectations were high for the 2018 conferences and upon the release of the official program I began pouring over the schedule. The four day conference goes by quickly with over 470 published papers and presenters are only given 20 minutes to discuss their research which could’ve taken years to complete. Topics ranged; from new lubricant testing with low-GWP refrigerants, to new compressor design, to equipment improvements and building system efficiency optimization results. Needless to say it was in my best interest to be prepared.
My week at Purdue started early on Sunday by attending a day long short course focused on the transition to flammable refrigerants, covering all matters related to a vast topic. The presenters ranged from the safety organizations, trade associations and the foremost university researchers on fire, flammability and flame characteristics … did I choice the right major? After a whirlwind brain cramming session on all things related to A2L and A3’s, I walked over to the ReNEWW and DC micro grid houses on campus for a tour and to discuss the possible future of what housing will look like. These living research projects are encouraging to see, when applied correctly all possibilities within the realm of sustainability can be reached. After an exciting but long day it was time to relive my college days by retreating back to our off campus housing, with a few other CAREL colleagues, and enjoy a beer while reviewing what we learned.
The conferences kicked off in full swing Monday morning with a keynote speech by industrial refrigeration guru Andy Pearson of Star Refrigeration, he reviewed the historic milestones achieved in the HVAC/R industry. Then explained how we have reached a standstill point, and proceeded to motivate the entire theater to use the next four days as an opportunity to collaborate, connect and innovate. By being dissatisfied with the current state of technology and continually striving for the great innovation the HVAC/R industry needs, we can break through the plateau and reach truly great possibilities in the realm of system efficiency and building sustainability.
Thanks to my expertly scheduled agenda, and full cup of coffee I was able to bounce around to hear presentations on: integrated thermal energy storage, electric vehicle compressor evaluation between scroll, rotary and rotary, refrigeration design for long-term space travels, personal comfort robot using phase change material for heat removal. I also listened intently to learn about a radiative sky cooler, that is similar to solar water heating but uses a special film on what looks like a solar panel to further subcool refrigerant circuits providing energy savings up to 10%. A session on numerical simulation of subcooling methods on VRF systems with Bypass or Vapor Injection followed. With five pages of notes and three hours passed, my hand was going to have carpal tunnel syndrome at this rate by the end of the week. The much welcomed break was a chance for another coffee and to enjoy catching up with a few industry colleagues. Back to the grind with more sessions after the break in rapid fire; very high heatpump application experiments, airflow optimization in a closed airflow heatpump clothes dryer, performance simulation of CO2 transcritical heatpump, design software performance improvements of existing systems, lubricant test results with low-GWP refrigerants… and on, and on, and on….
Now writing this blog in hindsight it is hard to tell when one day ended and the next began, the wealth of rich knowledge continued to pour throughout the entire week. Advancements in the study of frost growth and detection on various heat exchangers were more fascinating than I ever could have imagined, and one day could lead to a break through that no coil will ever frost again! I attended numerous presentations on: specific research related to vibration within compressor and attempted ways to resolve. A compressor manufacturer shared with the market for the first time a new larger twin-rotary with countless improvements to eek capacity and improve efficiency. There was a riveting new concept on a traditional rotary compressor that would increase volumetric compression and decrease required raw materials; this technology was called coupled-vane and presented by the University of Singapore, I will be following this with a hopeful eye in the future.
More and more research presentations on flammable refrigerants and compatible lubricants on various different types of applications performed by the most advanced university and industrial research laboratories. There were countless presentations on heat exchanger optimization and designs; round tube-plate fin downsizing to 2 or 3 mm, microchannel maldistribution modelling and experiments. Then I stumbled into the advanced alternatives to the vapor compression cycle … think of the future of HVAC/R systems without a compressor. There are countless technologies with promising results and one day there may be a break through which will revolutionize not only our industry but our way of life; thermoelastic, magnetocaloric, electrocaloric, thermoionic, and thermoelectric to name a few…
My head is still spinning, and a bit sore with all the new information crammed into my admittedly pea-sized brain. The 2018 Purdue Conferences were truly revolutionary and I believe lots of research that was presented in the past week will innovate our industry and can truly save our world. This work will continue to inspire creativity and push the boundary of what is possible toward the next big break through. When that ceiling is shattered, I will be proud to have taken part in such an amazing event and embrace the new technology in order to apply to the market as wide as possible. I have already marked 12-16 July 2020 on my calendar and will almost certainly be attending the next Purdue Conferences, will you?
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