In this study, we enhance the understanding and design of a radiant cooling technology for outdoor comfort in tropical climates, originally proposed by R.N. Morse in 1963, in this journal. We investigate a type of radiant cooling methodology whereby the cold temperature source is physically separated from the outdoor environment by an insulated enclosure using a membrane transparent to infrared radiation. The enclosure isolates the radiant cooling surface from ambient conditions, allowing the radiant surface to be cooled significantly below ambient dew point temperatures without incurring condensation. For this new study, a Fourier Transform Infrared (FTIR) Spectroscopy analysis on three candidate membrane materials is undertaken and a prototype experimental test panel is fabricated. Our study shows that for a 5°C chilled panel temperature, the exterior membrane surface temperature reaches 26°C in a 32°C / 70% RH environment resulting in an effective mean radiant temperature of 15.8°C. These results provide new evidence in support of Morse’s original proposal, that such panels could provide significant radiant cooling without condensation in humid environments. Radiant cooling products based on the studied technology may offer an ability to provide thermally comfortable conditions in hot environments without the energy required for dehumidification.
CHAOS Lab symposium on the Energy Water Nexus and the role of carbon and natural systems for the challenges in our urban environment and infrastructures
9:00 am: Welcome message and Introduction to Energy+Water+Urban by Dr. Forrest Meggers
9:30 am: Noah Stern, Water + Carbon + Environment. Followed by Q/A
The Water and Carbon cycles are arguably the most important cycles for humankind to understand. The water cycle is the largest cycle on the planet, and the carbon cycle is at the heart of the threat of climate change. Current models of sediment carbon dynamics focus on preservation of organic carbon through formation of carbon-mineral aggregates. However, the preservation of carbon in these soil aggregates depends on their stability. My research focuses on the importance of particulate organic carbon in the development of microbial hot-spots where highly elevated release rates of CO2 and CH4 occur. Connecting the contribution of particulate organic carbon to the freshwater carbon cycle has large implications for natural and engineered environments.
10:00 am: Hongshan Guo & Erica Edwards, NSF-SRN UWIN – Urban water, humidity, surfaces and radiant comfort
11:00 am: Eric Teitelbaum & Michael Bozlar,
I.) Applications of Liquid Desiccant in Building Dehumidification.
II.) Evaporative Cooling using Hydrophilic Substrates
12:00 pm: James Coleman & Nicholas Houchois, Distributed and Intelligent Sensors
12:30 pm: Concluding remarks by Forrest Meggers
12.45 pm Adjourn – Lunch
Forrest was invited to Berkeley for the annual meeting of the CBE including meetings with former collaborator in Singapore and at Princeton, Jovan Pantelic, in his new role as professional researcher at the Berkeley Center for the Built Environment. Research in advanced sensors, comfort, and radiant heating and cooing were all discussed, and current CHAOS research projects were well-received and many potential collaborations were initiated. Forrest also met with Prof. Ed Arens, who shares a mutual appreciation for the Olgyay research in Princeton in the 50’s and 60’s. Arens will be a Highlight Seminar speaker at the Andlinger Center Feb 8th.
The Thermoheliodome was featured on the cover of the Andlinger Center for Energy and Environment Annual Report
View Report here: http://acee.princeton.edu/wp-content/uploads/2014-Anglinger-Annual-Report-FINAL.pdf