Spacecraft Thermal and Fluids Systems Laboratory

Creative Flow Research Division

Spacecraft Thermal and Fluids Systems Laboratory

Professor
Hiroki
Nagai
Assistant Professor
Koji
Fujita

A spacecraft is exposed to various thermal-fluid environments from the time of launch to the period in space and return to the Earth. Understanding of thermal and aerodynamic characteristics in re-entry to the atmosphere is essential especially in the development of the next-generation space transportation systems. In this study, we study the methods to estimate the aerodynamic heating by using functional molecule sensors, and study and develop thermal-fluid measurement technology which can be used to measure extreme environment fields with high temperatures (1000°C and higher) as well as cryogenic temperatures. For the next-generation spacecraft which is to carry out missions over long periods under extreme thermal environments, it is essential that they have thermal control systems capable of exhausting heat from the internal devices using the limited electricity and weight resources. This laboratory, therefore, tries to address this demand and bring about a breakthrough in a realization of next-generation spacecraft missions through our research and development of loop heat pipes (LHPs) and oscillating heat pipes (OHPs) as light-weight and space-saving/non-electric heat transport devices.

Understanding of aerodynamic characteristics and aerodynamic heating phenomenon when a spacecraft enters the planet atmosphere.

We focus on the aerodynamic heating phenomenon occurring in the hypersonic region when a spacecraft enters the atmosphere of a planet (planet with the atmosphere such as the Earth and Mars), and the dynamic instability phenomenon related to the entry capsule when it decelerates from there to supersonic and transonic speed. For the former, we conduct research on measurement methods (including inverse problem solution methods) which can be used to estimate the aerodynamic heating which occurs on the body of the spacecraft directly with high precision using Temperature-Sensitive Paint (TSP). However, considerable problems remain in its measurement, and we will try to establish a new method which is more advanced than the current ones. We would also like to try to establish the database for spacecraft body design in fusion with CFD, in addition to measurement.

Development of thermal control devices and innovative thermal systems for next-generation spacecraft

We will research and develop thermal control devices utilizing gas-liquid two-phase flow (LHP, OHP, Mechanical Pump Loop and so forth). Especially since LHP/OHP has no driving parts, expectations are high for installation in deep space spacecraft with limited resources as lightweight, space-saving non-electric thermal transport devices. Finally, we will try to propose an electricity-saving, high-efficiency innovative spacecraft thermal control system which combines these.

Research and development of new exploration systems utilizing the “fluid-dynamic forces” on planets with atmosphere such as airplane

At present, we conduct research and development of Mars airplane to explore while flying through the atmosphere of Mars. A special focus of this study is to develop a super-high performance airfoil in low Reynolds number region and understand its flow field, as well as its fluid and flight control (airborne unfolding of the wings). We also plan to conduct flight demonstrations at the elevation around 35km on earth, which has an equivalent flight environment as Mars, to show its feasibility ahead of the world. We will try to propose a new exploration system (Planetary Locomotion) which utilizes the fluid-dynamic forces such as the airplane for other planets with the atmosphere through this research.

Spacecraft Thermal and Fluids Systems Laboratory