# Aerodynamic Characteristics of Re-Entry Capsules with Hyperbolic Contours

## Abstract

**:**

## 1. Introduction

## 2. Design of Re-Entry Capsule Shape Using Hyperbolic Contours

## 3. Numerical Methods and Computational Grid

## 4. Results and Discussions

#### 4.1. Grid Study

#### 4.2. Pressure Distribution

#### 4.3. Aerodynamic Characteristics

#### 4.4. Comparison of Volume and Stagnation Point Heat Flux

## 5. Conclusions

- The drag and lift coefficients can be increased when compared to the Hayabusa capsule.
- The static longitudinal stability was not affected significantly.

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 5.**Pressure coefficient distribution on the symmetry plane with different computational grids.

**Figure 6.**Pressure coefficient distribution on the symmetry plane with different hyperbolic contours at an AoA of 0 degrees.

**Figure 7.**Pressure coefficient distribution on the symmetry plane with different hyperbolic contours at an AoA of 15 degrees.

**Figure 8.**Pressure coefficient distribution on the forebody of the capsules with hyperbolic contours at an AoA of 15 degrees.

**Figure 12.**Effect of parameter of hyperbolic contours on the relative value of the volume and the stagnation point heat flux of the capsule.

**Table 1.**Comparison of drag coefficient and the number of computational cells, faces, and nodes with different computational grids.

Fine | Nominal | Coarse | |
---|---|---|---|

Drag coefficient | 1.12986 | 1.12501 | 1.11057 |

Normalized drag coefficient | 1.0000 | 0.9957 | 0.9829 |

Number of cells | 5,032,000 | 963,596 | 265,743 |

Number of faces | 14,648,152 | 2,748,156 | 740,877 |

Number of nodes | 4,538,027 | 806,003 | 203,326 |

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**MDPI and ACS Style**

Otsu, H.
Aerodynamic Characteristics of Re-Entry Capsules with Hyperbolic Contours. *Aerospace* **2021**, *8*, 287.
https://doi.org/10.3390/aerospace8100287

**AMA Style**

Otsu H.
Aerodynamic Characteristics of Re-Entry Capsules with Hyperbolic Contours. *Aerospace*. 2021; 8(10):287.
https://doi.org/10.3390/aerospace8100287

**Chicago/Turabian Style**

Otsu, Hirotaka.
2021. "Aerodynamic Characteristics of Re-Entry Capsules with Hyperbolic Contours" *Aerospace* 8, no. 10: 287.
https://doi.org/10.3390/aerospace8100287