九州大学 エネルギー基盤技術国際教育研究センター

Energy Storage Division – Shigeru KOYAMA –

Heat Storage Technology Research Field

Professor

Shigeru KOYAMA

Specialization

Thermal Engineering, Heat and Mass Transfer, Heat Pump and Refrigeration Systems

Affiliation

Faculty of Engineering Sciences

Research Topics

  • Heat transfer of next-generation working fluids for heat pump and refrigeration systems
  • Heat and mass transfer in porous solid-vapor pairs
  • Improvement of cycle performance of vapor compression heat pump systems
  • Development of heat pump cycle for thermal recovery from waste heat
  • Development of heat pump cycle for thermal recovery from waste heat

Research Outline

Recently, the awareness on environment and energy related problems are being increased. In these regards, one of the major concerns is to develop high performance heat pump and refrigeration systems employing environment-friendly working fluids. The development of advanced thermal energy conversion systems, which effectively exploit waste heat below 100 oC, is also gaining increasing attention. In order to construct such systems, we are involved in clarifying the heat and mass transfer mechanism in vapor-liquid phase change of environment-friendly working fluids and adsorption process of vapor into porous solid adsorbents. We are contributing significantly to the development of innovative heat pump and refrigeration systems and incremental improvement of existing technologies.

Search for environment-friendly working fluids

Search for environment-friendly working fluids

We are searching for environment-friendly working fluids with low GWP in order to replace the existing ones with high GWP.

Condensation and boiling of an environment-friendly working fluid R1234ze(Z)

Condensation and boiling of an environment-friendly working fluid R1234ze(Z)

We are evaluating the heat transfer characteristics of R1234ze(Z)condensing and boiling on a horizontal tube in order to develop high performance heat exchangers for heat pump and refrigeration systems.

Electrochemical window of aqueous Na-ion batteries (left) and the redox voltage of the various cathode/anode candidates (right).

Development of high temperature heat pump for heat recovery from waste heat

In order to develop high temperature heat pump systems for heat recovery from industrial waste heat below 100 oC, we are assessing the thermodynamic cycle performance of various heat pump systems.