Energy system & component design

06

Energy system &
component design

Generating electricity is getting more important in modern society. To meet the needs, safer and efficient power plant systems are extensively investigated. Since the basic components of the energy power plant system are thermodynamic cycles, improving each component such as heat exchangers for boiler and condenser, compressors, and turbines is also an issue in the field. Based on the understanding of thermodynamic cycles and heat & fluid dynamics, we are working on optimizing energy components to design the whole energy layout for future energy systems.
Printed Circuit Heat Exchanger (PCHE) design

PCHE is one of compact heat exchanger which can sustain high pressure and high temperature conditions due to the structural rigidity. They are widely chosen as a heat source and sink for a compact supercritical Brayton cycle power conversion system. The densely-stacked structure allows high compactness, and the diffusion-bounded junctions enable high rigidity. However, the optimized channel designs for PCHE is not yet determined. Therefore, we are actively working on understanding what phenomena happen in PCHE and find out the best channel designs for energy system applications.

Using low temperature heat for power generation
To mitigate environmental effects of coal-burning power plant, natural gas is regarded as a promising energy resource of clean energy because there is a little emission of CO2 and sulfur oxides compared with conventional coal power plant (however, still natural gas power plant emits global warming gas such as methane [the main element of natural gas] and some dust). Due to the large volume of natural gas, Liquefied Natural Gas (LNG) is actively used in actual industries and power plants. The thing is that the regasification process is required for actual use, and the regasification process used about 830 kJ/kg, which is waste energy called ‘cold energy’. To use low temperature energy for generating electricity, various energy layouts are considered, and we are investigating the optimized energy layout for Organic Rankine Cycle (ORC).
Sodium Fast Reactor (SFR) energy system layout design

A Sodium Fast Reactor (SFR) is a fast neutron reactor cooled by liquid sodium. Since the potential to use current Light Water Reactor (LWR) nuclear waste as nuclear fuel with the reprocessing procedure, SFR is considered as one solution to handle current nuclear waste problems. However, the detail layout of SFR is not yet fixed. Our group is actively working on to consider safety components preventing water-sodium reaction and to design actual SFR energy system layout. including heat exchanger as well as turbomachinery.