New arrival information

2022.4.11

Updated members

2022.3.25

Laboratory members have completed their studies.
Thank you and congratulations!

In our Laboratory...

Objects that cannot be kept in their shape unless they are put in the container like water or air is called "fluid", fluid dynamics is the study to research how fluids flow. In fluid dynamics, the flows of water and air are targets in many cases. As you see from the fact that the weather forecast hardly hit, the phenomena "fluid" is difficult for the analysis by the computer to predict accurately, there are still so many unknown fields. Therefor it is said that among the mechanical researchers, the proportion of people who specialize in fluid dynamics is the largest, the specialists of fluid dynamics are needed widely in university and corporation. Our laboratory focuses on "dynamics of complex fluids" and "fluid induced vibration" among fluid dynamics and conducts research and development.

We are publishing interesting videos on rheology.

What is dynamics of complex fluids?

Since water and air are overwhelmingly large quantities on the earth, most researchers of fluid dynamics study water or air flow. However, there are many "flowing objects" other than water and air in our surroundings. Although mayonnaise and ketchup can maintain its shape even if it is taken out from the container, it can "flow" easily from the container. You can know intuitively that it is totally different from the flow of water. Physiological fluid such as blood, paint such as ink and paint, cosmetics, cement, plastic, liquid crystal, etc, there are many examples of materials that flow in completely different ways from water and air. Conversely in the classification of "fluid" it would be better to think that water and air are special and most fluids do not flow in different ways. Water and air are called "Newtonian fluid", while other fluids are called "non-Newtonian fluid" or "complex fluid". Recently, soft liquids are collectively called "soft matter". The flow behavior of a complex fluid is so complicated as to be incomparable with water and air, and special measuring equipment and original research equipment are required. There is big interest to the analysis of flow with regard to complex fluid in industry because it can make high functional products.

Some complex fluids are emulsions in which oil droplets are floating in liquid (such as milk), and suspensions in which microscopic particles are suspended. By using a fluid containing rod-like or tabular micro particles (submicron to submillimeter size) as a paint and flowing under appropriate conditions, it is possible to align the direction of the particles. This technique is fluid orientation, which can be mass- produced inexpensively highly functional thin film with rod/ plate particles/ molecules aligned cleanly.

Our laboratory focuses on various phenomena such as flow of complex fluid and measurement of physical properties, molecular / particle orientation technique by flow, phase change / structural change due to flow, and so on.

What is fluid induced vibration?

Our laboratory also conducts research on vibration phenomena by flow, that is, "fluid induced vibration". When the wind blows, electric wires and bridges shake, occasionally accidents such as cutting and collapse occur. Vortex is generated by the flow of water and air. When the periodic outflow of vortex and natural frequency agree with each other, sympathetic vibration phenomena occur and vibrate. After that, if it shifts to a more destructive vibration mode, destruction of the structure will occur.