All posts by Eric Teitelbaum

Eric Teitelbaum in Singapore managing ColdTube project

CHAOS Lab Ph.D. candidate Eric Teitelbaum has temporarily relocated to the Singapore-ETH Centre to manage the engineering, design and research behind a sub-dewpoint outdoor radiant cooling pavilion. The system uses thermal windows to create cold surfaces that your body sees, but that are not directly in contact with the warm, humid tropical Singaporean air. It’s the first study of its kind, assessing how radiantly cooled occupants feel with an entirely radiantly cooled system. Stay tuned for updates!

Teitelbaum hiding behind a thermally transparent material.
ColdTube pavilion rendering.

Dorit Aviv wins grant to bring ‘Cool Oculus’ thesis project to CHAOS

The focus of Dorit Aviv’s Master’s Thesis (M.Arch 2014), Cool Oculus uses a dynamic form, similar to that found in a Hoberman Sphere, to match radiant and downdraft evaporative cooling strategies to diurnal cycles. Dorit won a Tides Foundation grant to work with Assistant Professor Forrest Meggers at Princeton University’s Andlinger Center to develop her project into a passive cooling system prototype.

Rendering of Cool Oculus installation
Daytime rendering of Cool Oculus installation

When installed, the structure acts as a downdraft evaporative chimney during the day, using natural convection to draw evaporatively cooled air from the top through the structure. At night, the structure opens and allows the slab below to radiantly cool through a radiant exchange with the desert night sky.

We look forward to collaborating with Dorit on the build!

Novel Mean Radiant Temperature Sensing

Radiant heat transfer is an often overlooked component in building design, not due to lack of importance (radiant temperature is as important as air temperature when describing comfort), but because of lack of monitoring devices. The average, or mean radiant temperature in a room is a position-dependent, air-independent parameter that is often imprecise and expensive to measure.

CHAOS has developed a novel radiant temperature sensor that uses servos to trace the surface of a sphere in space with a non-contacting infrared temperature sensor. The sphere shape is convenient as it mimics conventional black-globe mean radiant temperature sensors. However, our design creates one pixel of temperature data at each data point, which can be stitched together to create a thermal image that provides the user with a directional thermal image of the room. In the image below you can see the sensor at work, finding a person in the room.

MATLAB Handle Graphics

 

Superhydrophobicity

IMG_8348_cropped
Trimethylchlorosilane-induced hydrophobicity on a porous crushed glass pellet for ECCENTRIC research. Contact angles up to 140° were observed.

CHAOS has worked extensively using chemicals to induce hydrophobicity on crushed glass ceramics. This is an interesting article on the future of superhydrophobicity through lasers, informed by the nanostructures of natural organisms.

http://scitation.aip.org/content/aip/journal/jap/117/3/10.1063/1.4905616

Outdoor Sensors Preview

The ThermoHelioDome has been winterized to prevent the bulbs from freezing by using a hot water heater to provide heat to circulating water. Track the performance of the dome’s heater here and the mean radiant temperature here. Eventually, the entire sensor network will be posted online.

ThermoHelioDome Construction + DAQ

Watch all aspects of our radiant cooling dome construction, from robot foam fabrication and hot wire cutting to truck rigging and gorilla gluing. At the end, check out the in-house design for mean radiant temperature sensing and the wet-bulb temperature depression through the cooling reflected by the dome’s dishes, viewed in the IR spectrum.

Read more about the ThermoHeliDome.

Read more about CHAOS and Infrared Sensing in Campus as a Lab.