Research Topics

Yasuyuki TAKATA(Professor)

Faculty of Engineering

Faculty of Engineering

Thermofluid Physics Laboratory

Hydrogen Storage Systems Lab.

Masamichi KOHNO

Naoya SAKODA(Associate Professor)(Assistant Professor)

Etsuo AKIBA(Professor)

Hai-Wen LI

Huaiyu SHAO

（Associate Professor）(Assistant Professor)

Highly efficient and safe hydrogen storage and transportation▶http://www.mech.kyushu-u.ac.jp/~heat/

Thermophysical Properties of Hydrogen

After the energy paradigm shift occurred because of the earthquake on March
11th 2011, energy storage, especially that of fluctuated renewable energy attractsmuch attention than before as well as mobile applications such as on board hydrogenstorage for fuel cell vehicle.
Hydrogen is gas at ambient temperature and pressure. The volume energy densityof hydrogen gas is only 1/3000 of gasoline, therefore, to store and transporthydrogen in a limited space is a critical issue to be solved before to realize thehydrogen economy. Hydrogen storage materials provide compact, energy efficient,safe and affordable method of hydrogen storage and transport). Our Laboratory
investigates hydrogen storage materials and develops novel materials those areindispensable to realize thehydrogen economy based on
fundamental studies.

Accurate thermophysical properties of hydrogen are essential
to provide reliable designs in the coming hydrogen society. PVT
property, viscosity and thermal conductivity are measured in thetemperature range from -40 ºC to 500 ºC and at pressures up
to 100 MPa. Based on the measured data, an equation of stateand correlation equations are developed. They are compiled in athermophysical property database, by which the thermophysicalproperties at any conditions are easily obtained.

Measurement Apparatus for HighPressure Hydrogen

The first fuel cell vehicle fromTOYOTA that stores hydrogenusing the material developedby Prof. Akiba and Dr. Iba(TOYOTA) in 1996.

The apparatus is originally designed and developed with remotecontrol system to achieve accurate measurement of thermophysicalFaculty of Engineering

properties of hydrogen at extremely high pressures up to 100

Solid Mechanics Lab.

MPa. The PVT property is measured by a magnetic suspension
densimeter. A vibrating wire viscometer is used for the viscosity
measurements, and the thermal conductivity is measured by thetransient short hot-wire method.

AB
Hiroshi NOGUCHI(Professor)

Shigeru HAMADA

Motomichi KOYAMA（Associate Professor）(Assistant Professor)▶http://www.mech.kyushu-u.ac.jp/~solid/

Hydrogen Effect against Strength Reliability of Materials
In order to use engineering structures safely in hydrogen environment
for a long time, hydrogen effect evaluation which affects mechanicalstrength is one of the most important issues. A carbon steel and a low
alloy steel are very promising material in economic point of view used inhydrogen environment. In order to use inexpensive material reasonably, it
is necessary to clarify fracture mechanism of the materials. Therefore, thefatigue behavior of the low carbon steel has been investigated in hydrogenenvironment.

C● Fatigue crack growth mechanism clarification and its application in hydrogen environment
A purpose of this study is toestablish the reasonable methodthat evaluates fatigue crack growthmechanism with fracture morphology
in hydrogen environment. From theresults, it is now possible for thefrequency dependency to evaluate Brittle striation morphologies that appeared onhydrogen environmental fatigue fracture surface
reasonably, which is very importantconsideration in hydrogen environment.

● Hydrogen effect investigation on a small fatigue crack behavior
A study on a small fatigue crack that spends most life time in total
fatigue life has been performed in hydrogen environment. In this study, thecondition which use safely in hydrogen environment has found through thesmall crack growth and fracture morphology analysis.

Measurement apparatus of hydrogen thermophysical properties(A) Magnetic suspension densimeter(B) Vibrating wire viscometer(C) Thermal conductivity apparatus by transient short hot-wire method5