HSL Special Seminar: Michael Strano, Jacopo Buongiorno (2 pm, 9/19, 33-206)

"Thermal management technologies for low temperature undersea dive persistence"

Michael S. Strano
Carbon P. Dubbs Professor
Chemical Engineering Department
Massachusetts Institute of Technology

Jacopo Buongiorno
TEPCO Professor and Associate Department Head
Nuclear Science and Engineering 
Massachusetts Institute of Technology

Abstract:

The central objective of this MIT research project is to explore new concepts in active and passive thermal management in order to generate new materials for low temperature undersea dive persistence. We target the form factor of a traditional neoprene wetsuit in order to preserve the dexterity and mobility of the diver. Passive concepts addressed in this work involve important modifications of conventional neoprene materials, including combined porosity engineering and nanocomposite strengthening. One passive strategy, in particular, that we address is facile impregnation of commercial neoprene with high molecular weight fill gases to achieve up to a 50% reduction in thermal conductivity that persists on the order of hours. These modified materials are shown to have practical application as a superior insulator. Active concepts in thermal management include the use of new MIT technology on energy harvesting from ambient temperature fluctuations – termed thermal resonators – using thermal diodes. Two new strategies for constructing high-performance phase change thermal diodes are described and demonstrated. The application of such thermal diodes in a thermal resonator circuit is also investigated and demonstrated.

Lastly, the development of seawater activated thermopower wave energy sources for high power density is discussed as an active concept in thermal management.