# Parametric Studies for Combined Convective and Conductive Heat Transfer for YASA Axial Flux Permanent Magnet Synchronous Machines

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## Abstract

**:**

## 1. Introduction

## 2. YASA Electromagnetic Models

## 3. YASA Thermal Models

#### 3.1. YASA LPTN

#### 3.2. 3D Thermal FEM Model

## 4. Coupled EM-Thermal Study

## 5. The Parametric Studies

#### 5.1. Air Gap Length Study

#### 5.2. Variable Speed Study

#### 5.3. Inward Heat Extraction Fins Thickness Study

#### 5.4. PM Thickness Study

## 6. Experimental Validation

## 7. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 4.**Machine Modeled parts (

**a**) Stator modeled part: (1) thermal insulation; (2) stator facing rotor upper part; (3) stator facing rotor lower part; (4) stator side wall. (

**b**) Rotor modeled part: (8) rotor facing stator upper; (9) rotor left side; (10) PM lower; (11) rotor lower; (12) PM upper; (13) rotor upper; (14) PM left; (15) PM right; (16) rotor facing stator.

Material | K (W/mK) | ${\mathit{C}}_{\mathit{p}}$ (J/kgK) | $\mathit{\rho}$ (kg/m${}^{3}$) |
---|---|---|---|

copper | 385 | 392 | 8890 |

aluminum | 167 | 896 | 2712 |

epoxy | 0.4 | 600 | 1540 |

nylon | 0.25 | 1600 | 1140 |

Nd-Fe-B | 9 | 500 | 7500 |

Parameter | Value | Unit |
---|---|---|

number of poles | 16 | - |

teeth number | 15 | - |

outer diameter housing | 195 | mm |

outer diameter active | 148 | mm |

PM thickness | 4 | mm |

rotor outer radius | 74 | mm |

slot width | 11 | mm |

Speed (rpm) | Analytical (${}^{\circ}$C) | FEM (${}^{\circ}$C) | Experimental (${}^{\circ}$C) |
---|---|---|---|

1000 | 61.73 | 63.89 | 62.74 |

2000 | 49.03 | 50.13 | 51.43 |

Speed (rpm) | Analytical (${}^{\circ}$C) | FEM (${}^{\circ}$C) | Experimental (${}^{\circ}$C) |
---|---|---|---|

1000 | 29.44 | 29.93 | 30.52 |

2000 | 26.89 | 27.05 | 28.12 |

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**MDPI and ACS Style**

Mohamed, A.H.; Hemeida, A.; Vansompel, H.; Sergeant, P.
Parametric Studies for Combined Convective and Conductive Heat Transfer for YASA Axial Flux Permanent Magnet Synchronous Machines. *Energies* **2018**, *11*, 2983.
https://doi.org/10.3390/en11112983

**AMA Style**

Mohamed AH, Hemeida A, Vansompel H, Sergeant P.
Parametric Studies for Combined Convective and Conductive Heat Transfer for YASA Axial Flux Permanent Magnet Synchronous Machines. *Energies*. 2018; 11(11):2983.
https://doi.org/10.3390/en11112983

**Chicago/Turabian Style**

Mohamed, Abdalla Hussein, Ahmed Hemeida, Hendrik Vansompel, and Peter Sergeant.
2018. "Parametric Studies for Combined Convective and Conductive Heat Transfer for YASA Axial Flux Permanent Magnet Synchronous Machines" *Energies* 11, no. 11: 2983.
https://doi.org/10.3390/en11112983