# Clocking and Potential Effects in Combustor–Turbine Stator Interactions

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## Abstract

**:**

## 1. Introduction

## 2. Experimental Apparatus and Measurement Technique

## 3. Numerical Model Description

^{TM}/Turbo NUMECA, a block-structured, density-based, Reynolds Averaged Navier–Stokes code based on a finite volume method. In the case of the presented investigations, a central difference spatial discretization with Jameson-type artificial dissipation [21] was applied, while for the temporal discretization, a four-stage explicit Runge-Kutta scheme was employed. In order to increase the convergence rate, the local time-stepping, implicit residual averaging and full multi-grid techniques were used in the solver.

^{6}grid cells for the combustor simulator only, up to 33.7∙10

^{6}grid cells for the model including cooled nozzle guide vanes. The mesh was refined close to the solid walls in order to keep y+ below 1. The block-structured topology was applied with a non-matching connection defined at the following interfaces: inlet duct–swirler, swirler–combustor simulator, combustor simulator–NGV and in the NGV vicinity at the connection between the skin layer including holes and the outer zone in the passage. An example of a mesh for a swirler, a combustor and for NGV cooling holes is shown in Figure 5. At the bottom, the block structure in the vicinity of the NGV cooling holes and the details of mesh topology in the hole are presented.

## 4. Combustor Simulator—Numerical Model Validation

## 5. Potential and Clocking Effect

## 6. Conclusions

## 7. Further Work

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 2.**Computational domain for a combustor simulator (

**a**) and a combustor simulator with NGV (

**b**).

**Figure 3.**Swirler and NVG relative position: leading edge clocking (LEC—(

**a**)) and passage clocking (PAC—(

**b**)).

**Figure 4.**Nozzle guide vane with cooling holes (

**a**) and details of plenum close to leading edge and pressure side (

**b**).

**Figure 7.**Non-dimensional total temperature at plane P40: 2D contour (

**a**) and circumferentially averaged (

**b**).

Name | Value |
---|---|

Total mass flow (per sector) (kg/s) | 0.240 |

Flow split: swirlers–liners (%) | 65–35 |

Chamber pressure (kPa) | 148 |

Flow temperatures (swirlers–liners) (K) | 512–Ambient |

Mach number at plane 40 (-) | 0.112 |

Name | Mass Flow Main Inlet (%) | Total Temperature (K) | Flow Angle (deg) |
---|---|---|---|

mp-ext 1 | 15 | 297.6 | 60 |

mp-ext 2 | 6 | 30 | |

mp-int 1 | 19 | 60 | |

mp-int 2 | 12 | 30 |

Name | Static Pressure | Total Temperature | Velocity Magnitude |
---|---|---|---|

$p$ | 1.75 | 3.40 | 5.84 |

${e}_{a}^{32}$ | 0.3% | 0.27% | 0.493% |

${e}_{ext}^{32}$ | 0.7% | 0.25% | 0.198% |

$GC{I}_{coarse}^{32}$ | 0.9% | 0.32% | 0.248% |

${e}_{a}^{21}$ | 0.1% | 0.4% | 0.28% |

${e}_{ext}^{21}$ | 0.4% | 0.7% | 0.20% |

$GC{I}_{fine}^{21}$ | 0.5% | 0.8% | 0.25% |

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**MDPI and ACS Style**

Flaszynski, P.; Piotrowicz, M.; Bacci, T.
Clocking and Potential Effects in Combustor–Turbine Stator Interactions. *Aerospace* **2021**, *8*, 285.
https://doi.org/10.3390/aerospace8100285

**AMA Style**

Flaszynski P, Piotrowicz M, Bacci T.
Clocking and Potential Effects in Combustor–Turbine Stator Interactions. *Aerospace*. 2021; 8(10):285.
https://doi.org/10.3390/aerospace8100285

**Chicago/Turabian Style**

Flaszynski, Pawel, Michal Piotrowicz, and Tommaso Bacci.
2021. "Clocking and Potential Effects in Combustor–Turbine Stator Interactions" *Aerospace* 8, no. 10: 285.
https://doi.org/10.3390/aerospace8100285