Experimental Investigation of Deformation of the Ballutes for Re-entry Vehicles in Supersonic Regime

抄録

In this study, we investigated the deformation of the ballute using the supersonic wind tunnel experiments at ISAS/JAXA. Due to the very high dynamic pressure of the wind tunnel, it was challenging to create the unbreakable flexible test model using the inflatable structure by gas. Thus, we tried to approximate the flexibility of the inflatable test model by using a hollow torus with a flexible material like hard rubber. The test model was the hollow polygon with a 50 mm major radius and 20 mm cross-sectional diameter. The test model was made of a flexible resin using a 3D printer Form 3. The flexibility of the test model was controlled by changing the inner diameter of the cross-section. In the wind tunnel experiments, the deformation of the ballute and the aerodynamic force on the ballute was measured. Experimental results showed that as the inner diameter increased, the deformation of the test model increased. The above result suggests that the current test model can simulate the flexibility of the test model. As for the drag force, as the inner diameter increased, the drag force decreased. This result suggests that the deformation of the ballute significantly impacts the drag force.