SUZUKI Kojiro

SUZUKI Kojiro

(Professor/Division of Transdisciplinary Sciences)

Department of Advanced Energy/Hypersonic High-Enthalpy Flow, Space Transportation System, Space Exploration Engineering

Career Summary

1985: Graduated, Dept. of Aeronautics, Faculty of Engineering, The University of Tokyo
1990: Doctor of Engineering from The University of Tokyo
1990: Research Associate, The Institute of Space and Astronautical Science
1993-94: Visiting Researcher at NASA JPL
1995: Associate Professor, Dept. of Aeronautics and Astronautics, Graduate School of Engineering, The University of Tokyo
1999: Associate Professor, Dept. of Advanced Energy, Graduate School of Frontier Sciences, The University of Tokyo
2008: Professor, Dept. of Advanced Energy, Graduate School of Frontier Sciences, The University of Tokyo

Educational Activities

Graduate School (Graduate School of Frontier Sciences): Fundamentals of Fluid Dynamics, Dynamics of High Enthalpy Flow
Graduate School (Graduate School of Engineering): Hypersonic Aerothermodynamics, Applied Computational Fluid Dynamics II
Undergraduate School (Department of Aeronautics and Astronautics): Aerodynamics IIA, Aerodynamics IIB, Aerodynamics V

Research Activities

The primary research topics in our laboratory are hypersonic high-enthalpy aerothermodynamics (Ref. 1) and high-speed flying vehicles in relation to future aerospace transportation and space exploration.
1) Innovative Atmospheric Entry Vehicles with Flexible Membrane Structure:
Flying vehicles with a flexible structure are expected to have some advantages over those with conventional rigid structure in various speed ranges. An atmospheric entry vehicle with a membrane aeroshell deployed before entry can decelerate with low aerodynamic heating in a very low-density atmosphere at very high altitudes. Such vehicles seem promising for realizing safe and low-cost space transportation vehicles and planetary entry probes. We have been studying these "dream" vehicles from various aspects. (Ref. 2)

Conceptual Model of Vertical Takeoff and Landing Rocket with Membrane Aeroshell(Left) and Flight Test of Capsule Model with Membrane Aeroshell, Dropped from JAXA's Balloon for Landing in the Pacific Ocean(Right)

2) Study on New Concepts of Space Exploration Vehicles:
For solar system exploration in the future, various new concepts are studied based on the knowledge of gasdynamics, such as aerocapture (orbit transfer using the aerodynamic force during atmospheric passage to save rocket fuel), solar probes (a probe penetrating into the solar corona) (Ref. 3), solar sail (a sail vehicle utilizing the photon pressure of the solar radiation), and magnetic sail (a sail vehicle utilizing a dynamic pressure of the solar wind).
3) Study on Nonequilibirum Gasdynamics:
From a meso-scopic viewpoint, various aspects of fluid flows are caused by deviations in the velocity distribution of gas molecules from their equilibrium state known as the "Boltzmann distribution". We are working on the kinetic model equation approach to describe thermochemical nonequilibrium phenomena. We have also performed numerical analysis of relativistic kinetic equation using a parallel supercomputer (Ref. 4) and an experimental study on the rarefied high temperature plasma flow of an inductively coupled plasma generator (Ref. 5), among other investigations.
4) Study on Hypersonic Transport:
To realize hypersonic transport flight at Mach numbers above 5, we have been conducting both a numerical study using CFD (Computational Fluid Dynamics) and an experimental study using the hypersonic wind tunnel at the Kashiwa campus.

CFD Analysis of Flow around a Waverider (a vehicle using the high pressure behind shock waves to obtain lift force)

Literature

1) Kubota, K., Suzuki, K. and Watanuki, T. "Aerothermodynamics of Space Vehicles", University of Tokyo Press (2002) in Japanese.
2) Yamada, K., Hongo, M. and Suzuki, K.: Aerodynamic Characteristics of Frustum-Shaped Elastic Membrane Aeroshells in Supersonic Flow, J. Spacecraft and Rockets, 43, pp. 690-693 (2006).
3) Suzuki, K.: Numerical Study of Behavior of Outgas from Heat Shield of Solar Probe, J. Spacecraft and Rockets, 43, pp.973-981 (2006).
4) Yano, R., Suzuki, K. and Kuroda, H.: Numerical Analysis of Relativistic Shock Layer Problem by Using Relativistic Boltzmann-kinetic Equations, Physica A, 381, pp. 8-21 (2007).
5) Takama, Y. and Suzuki, K.: Spectroscopic Diagnostics of Thermochemical Nonequilibrium Hydrogen Plasma Flow, J. Thermophysics and Heat Transfer, 21, pp. 630-637 (2007).

Other Activities

The Japan Society for Aeronautical and Space Sciences (JSASS)
American Institute of Aeronautics and Astronautics (AIAA)

Future Plan

In our laboratory, the relationship between the shape of an object and the air flow around it has been investigated to elucidate the shape of future aerospace vehicles. The hypersonic (Mach 7 and 8) and high-enthalpy wind tunnel, which has begun operation at the UT-Kashiwa campus in 2007, will become a powerful tool for this investigation.

Schlieren Picture of Shock Wave over Rocket Nose Model in Mach 7 Flow of Kashiwa Hypersonic Wind Tunnel

Messages to Students

Find a research theme to which you can devote yourself wholeheartedly, and strive for excellence in it. You can find great pleasure in grasping things that you were previously unfamiliar with, even for relatively minor problems. To extend the boundaries of your research field, do not hesitate to go beyond the familiar grounds of your specialty. Even when you cannot find any direct relation between two (or more) research fields, there may be an "invisible link" between them. In my experiences, I have realized that such "invisible links" may become hints for greater discoveries. I encourage you to challenge new frontiers in hypersonic high-enthalpy aerothermodynamics and the aerospace sciences.

URL

https://daedalus.k.u-tokyo.ac.jp/laboratory/index.html