Washington, July 31 (ANI): Researchers have developed a bioinspired microfluidic circulatory system for windows that could help save energy and cut cooling costs dramatically, while letting in just as much sunlight.
The same circulatory system could also cool rooftop solar panels, allowing them to generate electricity more efficiently.
The new window-cooling system contains an extensive network of ultrathin channels near the "skin" of the window-the pane-through which water can be pumped when the window is hot.
The channels consist of long, narrow troughs that are molded into a thin sheet of clear silicone rubber that, when stretched over a flat pane of glass, create sealed channels.
Benjamin Hatton, Ph.D., lead author of the study. Hatton, who is now an assistant professor of materials science and engineering at the University of Toronto, was a member of the Advanced Technology Team at the Wyss Institute, said that the water comes in at a low temperature, runs next to a hot window, and carries that thermal energy away.
He worked on the Adaptive Material Technologies platform led by Joanna Aizenberg, Ph.D., who is a Core Faculty member of the Wyss Institute and the Amy Smith Berylson Professor of Materials Science at Harvard School of Engineering and Applied Sciences.
The idea to cool glass windows when they get hot emerged from work on microfluidics by Don Ingber, M.D., Ph.D., the Wyss Institute's Founding Director, and his team working on biomimetic microsystems. Ingber is also the Judah Folkman Professor of Vascular Biology at Harvard Medical School and Boston Children's Hospital, and Professor of Bioengineering at Harvard School of Engineering and Applied Sciences.
Microfluidic devices circulate fluids through tiny, ultrathin channels and are typically used to build small devices for laboratory research and clinical diagnosis. In contrast, Ingber's team developed an innovative method to build large-scale microfluidic devices for organ-on-chip applications. They first use a vinyl cutter-a computer-controlled device that cuts intricate patterns on large vinyl sheets-to create a plastic mold. Then they pour liquid silicone rubber into the mold, let it solidify, and remove it, which creates the thin sheet imbued with long, narrow troughs.
When Ingber's microfluidics team met with Aizenberg's adaptive materials team in cross-platform meetings, the idea emerged that this microfluidics technology could be applied to building materials to control heat transfer, much like capillary blood flow warms the feet of Antarctic penguins as they wait for their mates near the South Pole.
Hatton and the Wyss Institute team then created and tested a four-inch-square microfluidic windowpane. They found that when these channels were filled with water, they were also transparent to the eye-which is just what people want in a window, Hatton said.
They then used a heat lamp to heat a pane with this vasculature to 100 F-as hot as a window might get on a sunny summer day. Using a special infrared camera, they showed that the circulatory system could readily cool the pane.
The Wyss Institute team then worked with Matthew Hancock, an applied mathematician at the Broad Institute in Cambridge, Mass., who developed a mathematical model that predicts how the circulatory system would perform on normal-size windows. Pumping just half a soda can's worth of water through the window's circulatory system would cool a full-size window pane by a full 8 C (14 F), they calculated.
The findings have been published in Solar Energy Materials and Solar Cells. (ANI)