Thermal system:
Thermodynamics
State and State Functions
Thermodynamic laws and principles
Thermal analysis
Thermal calculation
Thermal Cycle and Thermal Processes
Engineering Thermophysics
Thermal equilibrium: thermal equilibrium, force equilibrium, phase equilibrium, etc
Energy utilization: energy conversion, transmission, and utilization
Thermal equipment: boilers, steam turbines, heat pumps, etc
Energy technology:
Development and utilization of solar energy
Energy materials
renewable energy
Energy saving technology
Energy storage technology
Energy and Environmental Engineering
New energy vehicles
New energy materials and devices
energy efficiency 
Energy conversion and application, etc