# Large-Scale CAMUI Type Hybrid Rocket Motor Scaling, Modeling, and Test Results

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## Abstract

**:**

## 1. Introduction

#### 1.1. CAMUI Hybrid Rocket Engine and Simulator

#### 1.2. Scaling of Regression Model

## 2. Materials and Methods

#### 2.1. Regression Rate Formulas

^{2}/s with very few measurements over 600 kg/m

^{2}/s.

#### 2.2. Iterative Simulator

#### 2.3. Test Setup

#### 2.4. Motors Included

#### 2.5. Fuel Measurement Method

#### 2.6. Equivalent Burn Time

#### 2.7. Method of Comparison

## 3. Results

## 4. Discussion

## 5. Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## Nomenclature

$a$ | Empirical constant |

${D}_{p}$ | Port diameter (m) |

${D}_{pi}$ | Initial port diameter (m) |

${G}_{p}$ | Propellant mass flux (kg/s/m^{2}) |

$H$ | Height (between fore- and back-end surfaces) (m) |

${H}_{i}$ | Initial height (m) |

$md$ | Empirical constant (back-end surface) |

$mp$ | Empirical constant (port) |

$mu$ | Empirical constant (fore-end surface) |

$nd$ | Empirical constant (back-end surface) |

$nu$ | Empirical constant (fore-end surface) |

${r}_{fd}$ | Regression rate back-end surface (m) |

${r}_{fp}$ | Regression rate port (m) |

${r}_{fu}$ | Regression rate fore-end surface (m) |

RMS | Root Mean Square |

$tb$ | Burn time (seconds) |

## References

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**2017**, 11, 54. [Google Scholar] - Kamps, L.; Hirai, S.; Nagata, H. Hybrid Rockets as Post-Boost Stages and Kick Motors. Aerospace
**2021**, 8, 253. [Google Scholar] [CrossRef] - Nagata, H.; Ito, M.; Maeda, T.; Watanabe, M.; Uematsu, T.; Totani, T.; Kudo, I. Development of CAMUI hybrid rocket to create a market for small rocket experiments Testbed. Acta Astronaut.
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**Figure 5.**Burn time equivalent principle [9].

**Figure 7.**Model scaling performance for D400 based on D230 analysis (

**left**) and D100 analysis (

**right**).

Engine Name | Nr. of Fuel Blocks pr. Engine | Fuel Diameter (mm) | Nominal Thrust Level (kN) | Propellant Flux (kg/m^{2}/s) | Burn Times (s) |
---|---|---|---|---|---|

D100 | 10 | 100 | 2.5 | 200–570 | 2–5 |

D230 | 10 | 230 | 10 | 290–740 | 5–10 |

D400 | 16 | 400 | 40 | 230–420 | 7 |

Motor Series | Error rms (%) |
---|---|

RIE | 14.1 |

TTY | 10.8 |

Motor Series | Analysis Series Used | Error rms (%) |
---|---|---|

D400 | D230 | 22 |

D400 | D100 | 26 |

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## Share and Cite

**MDPI and ACS Style**

Viscor, T.; Kamps, L.; Yonekura, K.; Isochi, H.; Nagata, H.
Large-Scale CAMUI Type Hybrid Rocket Motor Scaling, Modeling, and Test Results. *Aerospace* **2022**, *9*, 1.
https://doi.org/10.3390/aerospace9010001

**AMA Style**

Viscor T, Kamps L, Yonekura K, Isochi H, Nagata H.
Large-Scale CAMUI Type Hybrid Rocket Motor Scaling, Modeling, and Test Results. *Aerospace*. 2022; 9(1):1.
https://doi.org/10.3390/aerospace9010001

**Chicago/Turabian Style**

Viscor, Tor, Landon Kamps, Kazuo Yonekura, Hikaru Isochi, and Harunori Nagata.
2022. "Large-Scale CAMUI Type Hybrid Rocket Motor Scaling, Modeling, and Test Results" *Aerospace* 9, no. 1: 1.
https://doi.org/10.3390/aerospace9010001