Energy and water are top two global challenges for the new millennium. The WE Lab focuses on science and technology for sustainable supply of energy and water. Synergic experiments and numerical simulations are applied to investigate multiscale mass and energy transport in water and energy technologies.
Non-diffusive heat transfer
With continuous decrease in the size of devices and structures, the manipulation and control of heat transport on the nanoscale is becoming a bottleneck in the development of many nanotechnologies, including micro-/nanoelectronics and thermoelectric energy conversion. A fundamental understanding of phonon-mediated heat transfer in nanostructures and across interfaces is crucial for breaking the developmental bottleneck of these nanotechnologies. Although molecular scale models can describe heat conduction over a few nanometers, and Fourier’s law delineates macroscale heat transfer over tens of microns or larger, a gap exists in heat conduction models between the molecular scale and the macroscale. The phonon Boltzmann transport equation (BTE) was supposed to fill this gap, but it is prohibitively expensive and a daunting challenge to solve with so many unknown parameters. Our research goal is to develop high-fidelity non-Fourier models to fill the gap for scientific research and engineering design involving nondiffusive heat transfer.
Mesoscale modeling and simulations of mass and energy
While macroscale transport in energy systems can be described by continuum principles, and atomistic scale transport can be calculated by molecular dynamics simulations, there is a lack of well-established mesoscale simulation tools that are necessary to bridge the continuum and atomistic descriptions. Mesoscale modeling and simulations of mass and energy transport in energy systems will provide the opportunities for breakthroughs in energy conversion, conservation, and storage.
Thermal management of electronics and energy storage systems
Energy consumption for the transportation sector is responsible for green house gases (GHG) emissions and air pollution. Electric vehicles (EVs) are 65% to 70% lower in GHG emissions. The widespread acceptatnce and adoption of Evs will significant benefits, including improved energy security, improved environmental and public health quality, and reduced auto fueling and maintenance costs. However, the performance, lifetime and safety of EV batteries highly depend on the operational temperature. The battery thermal management systems are critical to achieve high performance, to improve lifetime, and maintain the safety. Currently, we are working on feasible design of lithium-ion battery thermal management systems for electric vehicles and renewable energy storage.
Environment-friendly water desalination systems
Energy, water and food are ranked as the top three problems that humanity will face over the next 50 years. Water is not only vital to maintain public health, but also most valuable for agriculture, power generation, and manufacturing industries. Literally, it is water that fuels the growth of the world economy. With a rapidly growing population, there is increased water demand for drinking, sanitation, agriculture and industry. Currently, the world confronts the most serious water crisis: approximately 1.2 billion people live in the area of physical water scarcity and lack access to adequate clean water. By 2025, this number will increase to 1.8 billion. Our research goal is to develop environment-friendly water desalination systems for sustainable water supply.