Research
Nanoscale Phonon Thermal Transport
As a new family of materials genome, nanomaterials have triggered great attention due to their superior physical properties, being an attractive candidate for next-generation electronic, thermoelectric and optoelectronic applications. Thermal transport properties are the vital factors to determine the performance and lifetime of fabricated devices either for efficient heat dissipation or thermoelectric energy conversion. By controlling nanoscale phonon transport, we intend to design and tailor the thermal transport properties of nanomaterials and uncovering the underlying mechanism governing the transport process, via accurate structure, defect and strain engineering. From the theoretical view, we implement state-of-the-art computational methods to study the detailed length-scale dependent phonon interactions, mainly based on (i) molecular dynamics simulation with spectral phonon information, (ii) density functional theory driven phonon Boltzmann transport equation and (iii) atomic Green's function method.
Heat & Mass Transfer Enhancement of Phase Change Materials
Phase change materials (PCMs) as a promising approach to store (thermal) energy via the high latent heat have the advantages such as low-cost, green and chemically stable. However, traditional PCMs usually own the very low thermal conductivity which limits their wide applications upon energy storage sciences, except for low melting point metals which are extremely expensive. We investigated the heat and mass transfer in traditional organic PCMs and their thermal conductivity enhancement by extensive molecular dynamics simulation. From microscopic view, our results revealed the governing mechanism that limits the efficient heat transfer in organic materials and possible enhancement solutions via the crystallization effect from nanomaterials were proposed.
Power Battery Thermal Management for Electric Vehicles
We performed both experimental and theoretical studies to investigate the heat transfer and energy storage mechanism in electric vehicle (EV) power battery in that temperature has the remarkable influence on the safety, performance and lifetime of EV power battery. In order to impose heat transfer enhancement, a coupled thermal management system for EV power battery was proposed by integrating phase change materials (PCMs, e.g. organics including paraffin, alcohol and fatty acid) and heat pipe technology. The well-known low thermal conductivity of organic PCMs was further optimized through introducing highly thermal conductive nanomaterials (e.g. graphene and h-BN) to construct the PCM nanocomposites. A safer working condition, better performance and longer lifetime of EVs can be achieved by such a coupled thermal management system by controlling the temperature (difference) as well as its distribution. Therefore, we ultimately facilitate the development of EVs as a clean and green approach to utilize energy in the future.
These work won the diverse national college student competitions in China as the gold medal, first prize, etc.
Current or unpublished work is not shown here.