Dual Phase Change Thermal Diodes for Enhanced Rectification Ratios: Theory and Experiment
Abstract
Thermal diodes are materials that allow for the preferential directional transport of heat and are highly promising devices for energy conservation, energy harvesting, and information processing applications. One form of a thermal diode consists of the junction between a phase change and phase invariant material, with rectification ratios that scale with the square root of the ratio of thermal conductivities of the two phases. In this work, the authors introduce and analyse the concept of a Dual Phase Change Thermal Diode (DPCTD) as the junction of two phase change materials with similar phase boundary temperatures but opposite temperature coefficients of thermal conductivity. Such systems possess a significantly enhanced optimal scaling of the rectification ratio as the square root of the product of the thermal conductivity ratios. Furthermore, the authors experimentally design and fabricate an ambient DPCTD enabled by the junction of an octadecane‐impregnated polystyrene foam, polymerized using a high internal phase emulsion template (PFH‐O) and a poly(N‐isopropylacrylamide) (PNIPAM) aqueous solution. The DPCTD shows a significantly enhanced thermal rectification ratio both experimentally (2.6) and theoretically (2.6) as compared with ideal thermal diodes composed only of the constituent materials.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 15, 2018
- Source ID
- 10.1002/aenm.201702692
Entities
People
- Albert Tianxiang Liu
- Anton L. Cottrill
- Michael Strano
- Song Wang
- Wen‐jun Wang
Organizations
- King Abdullah University of Science and Technology
- Massachusetts Institute of Technology
- National Natural Science Foundation of China
- Office of Naval Research
- Zhejiang University