TOP > Report & Column > The Forefront of Space Science > 2015 > New Concepts of the Atmospheric-entry Vehicles

| 1 | 2 | 3 | A “Balloon�EProof Against the Aerodynamic Heating Next is the heating issue. Above we have introduced that the surface temperature of the aeroshell will be 1000°C while reentering. The maximum temperature of a reentering space shuttle is 1600°C, and when it comes to the return capsule of HAYABUSA, it is said that the temperature was 3000°C. Therefore, in comparison, the environment is rather moderate. In fact, it is just the most important feature of this system that heating is dramaticaly reduced compared to the reentry vehicles so far. During real development, we have to see whether the aeroshell we made is proof against such environment. Therefore, firstly we have to create the environment in the laboratory. Figure 3 shows the facility we made to produce the heating environment while reentering. We heat the air with electricity to create hot air plasma. (To say it in an easy-to-understand way, it is like a microwave oven). Figure 3. The Inductively Coupled Plasma (ICP) heating facility developed to simulate the reentering environment, together with the aeroshell model in heating experiment. [Click for large image] Although it is a 2㎡ size facility, the internal temperature can reach 8000°C. At such a high temperature, the air will emit light, which is the so-called plasma state. The photo on the left of figure 3 is the situation when the “balloon�Esimulating the aeroshell of the future reentry vehicle was put into the air plasma flow, which was produced by this facility. The balloon was exposed to the hot air plasma, and the surface temperature reached nearly 1000°C, but the balloon did not break for several minutes. Although the experiment is just getting started, with this facility, we can decide the structure of the real aeroshell by changing the material or measuring its internal temperature. Conclusion The atmospheric-entry technology, together with the landing and recovering technologies, has been the key technologies to make flexible space activity and attractive planetary explorations. To add a new choice for this, we are doing our best to realize the deployable reentry vehicles. The research and development of the deployable reentry vehicles are in progress steadily after the success of the atmospheric reentry experiment by the sounding rocket, and it is close at our hand to firstly apply the technology to the reentry system of the small satellites of which the size is limited. Furthermore, this solution can make efficient use of the aerodynamic force, so we are considering to apply this technology to the probes towards planets with thinner atmosphere like Mars. In this article, we have focused on the new reentry vehicle, the development and issues of the deployable aeroshell. However, it is not the only issue in the evolution of the atmosphere reentry and landing and recovering technologies. For example, after reentering the atmosphere with the flexible aeroshell, what if we were able to land it at a certain destination using the flexibility? Furthermore, what if made a reentry vehicle that could always come to the place where we are through a satellite phone or a GPS device? The days when we could receive the delivery from space at our home... The future reentry vehicles might become a reality in a form beyond our imagination. (Kazuhiko Yamada) | 1 | 2 | 3 |

• Back to top