Large Eddy Simulation of Film Cooling Involving Compound Angle Hole with Bulk Flow Pulsation
The effects of pulsations in the main flow on film cooling from a cylindrical hole with a spanwise injection angle (orientation angle) are analyzed using numerical methods. The hole is located on a flat plate with a 35° inclined injection angle, and the compound angle denotes the orientation and inc...
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| Format: | Article |
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MDPI AG
2021-11-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/14/22/7659 |
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| author | Seung-Il Baek Joon Ahn |
| author_facet | Seung-Il Baek Joon Ahn |
| author_sort | Seung-Il Baek |
| collection | DOAJ |
| description | The effects of pulsations in the main flow on film cooling from a cylindrical hole with a spanwise injection angle (orientation angle) are analyzed using numerical methods. The hole is located on a flat plate with a 35° inclined injection angle, and the compound angle denotes the orientation and inclination angles. The film cooling flow fields for the sinusoidal flow pulsation of 36 Hz from a cylindrical hole with 0° and 30° orientation angles at the time-averaged blowing ratio of <i>M</i> = 0.5 are simulated via large eddy simulation (LES). The CFD results are validated using the experimental data and compared to the Reynolds-averaged Navier–Stokes (RANS) and URANS results. The results reveal that if the pulsation frequency goes from 0 to 36 Hz, the adiabatic film cooling effectiveness decreases regardless of the compound angle; however, the film cooling for the 30° orientation angle exhibits better performance than that for a simple angle (0°). Moreover, if 36 Hz pulsation is applied, the film cooling effectiveness obtained by unsteady RANS exhibits a large deviation from the experimental data, unlike the LES results. The credibility of the LES results relative to the experimental data is demonstrated by comparing the time-averaged <i>η</i> and the phase-averaged temperature contours. The LES results demonstrate that LES can more accurately predict <i>η</i> than the experimental data; in contrast, URANS results are highly overpredicted around the centerline of the coolant spreading. Thus, LES results are more consistent with the experimental results for the time- and phase-averaged temperature contours than the URANS results. |
| first_indexed | 2024-03-10T05:32:30Z |
| format | Article |
| id | doaj.art-5dabc969e8bb4d3aa5d9c32f53070789 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-10T05:32:30Z |
| publishDate | 2021-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-5dabc969e8bb4d3aa5d9c32f530707892023-11-22T23:11:37ZengMDPI AGEnergies1996-10732021-11-011422765910.3390/en14227659Large Eddy Simulation of Film Cooling Involving Compound Angle Hole with Bulk Flow PulsationSeung-Il Baek0Joon Ahn1School of Mechanical Engineering, Kookmin University, 77 Jeongneung-ro, Seongbuk-gu, Seoul 02707, KoreaSchool of Mechanical Engineering, Kookmin University, 77 Jeongneung-ro, Seongbuk-gu, Seoul 02707, KoreaThe effects of pulsations in the main flow on film cooling from a cylindrical hole with a spanwise injection angle (orientation angle) are analyzed using numerical methods. The hole is located on a flat plate with a 35° inclined injection angle, and the compound angle denotes the orientation and inclination angles. The film cooling flow fields for the sinusoidal flow pulsation of 36 Hz from a cylindrical hole with 0° and 30° orientation angles at the time-averaged blowing ratio of <i>M</i> = 0.5 are simulated via large eddy simulation (LES). The CFD results are validated using the experimental data and compared to the Reynolds-averaged Navier–Stokes (RANS) and URANS results. The results reveal that if the pulsation frequency goes from 0 to 36 Hz, the adiabatic film cooling effectiveness decreases regardless of the compound angle; however, the film cooling for the 30° orientation angle exhibits better performance than that for a simple angle (0°). Moreover, if 36 Hz pulsation is applied, the film cooling effectiveness obtained by unsteady RANS exhibits a large deviation from the experimental data, unlike the LES results. The credibility of the LES results relative to the experimental data is demonstrated by comparing the time-averaged <i>η</i> and the phase-averaged temperature contours. The LES results demonstrate that LES can more accurately predict <i>η</i> than the experimental data; in contrast, URANS results are highly overpredicted around the centerline of the coolant spreading. Thus, LES results are more consistent with the experimental results for the time- and phase-averaged temperature contours than the URANS results.https://www.mdpi.com/1996-1073/14/22/7659large eddy simulationReynolds-averaged Navier–Stokes simulationgas turbine coolingfilm cooling |
| spellingShingle | Seung-Il Baek Joon Ahn Large Eddy Simulation of Film Cooling Involving Compound Angle Hole with Bulk Flow Pulsation Energies large eddy simulation Reynolds-averaged Navier–Stokes simulation gas turbine cooling film cooling |
| title | Large Eddy Simulation of Film Cooling Involving Compound Angle Hole with Bulk Flow Pulsation |
| title_full | Large Eddy Simulation of Film Cooling Involving Compound Angle Hole with Bulk Flow Pulsation |
| title_fullStr | Large Eddy Simulation of Film Cooling Involving Compound Angle Hole with Bulk Flow Pulsation |
| title_full_unstemmed | Large Eddy Simulation of Film Cooling Involving Compound Angle Hole with Bulk Flow Pulsation |
| title_short | Large Eddy Simulation of Film Cooling Involving Compound Angle Hole with Bulk Flow Pulsation |
| title_sort | large eddy simulation of film cooling involving compound angle hole with bulk flow pulsation |
| topic | large eddy simulation Reynolds-averaged Navier–Stokes simulation gas turbine cooling film cooling |
| url | https://www.mdpi.com/1996-1073/14/22/7659 |
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