Active Turbulence Grid-Controlled Inflow Turbulence and Replication of Heat Exchanger Flow Fields in Fan Applications
A novel active turbulence grid of the Institute of Fluid Mechanics at FAU Erlangen-Nuremberg is introduced. The focus of this grid is not on basic investigations of fluid mechanics, as is usually the case with active turbulence grids, but the generation of defined inflow conditions for axial fans. T...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-01-01
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| Series: | International Journal of Turbomachinery, Propulsion and Power |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2504-186X/8/1/1 |
| _version_ | 1797858429475225600 |
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| author | Felix Czwielong Stefan Becker |
| author_facet | Felix Czwielong Stefan Becker |
| author_sort | Felix Czwielong |
| collection | DOAJ |
| description | A novel active turbulence grid of the Institute of Fluid Mechanics at FAU Erlangen-Nuremberg is introduced. The focus of this grid is not on basic investigations of fluid mechanics, as is usually the case with active turbulence grids, but the generation of defined inflow conditions for axial fans. Thus, by means of the active turbulence grid, individual turbulence characteristics in the flow to the fan can be changed; therefore, fundamental interactions between the flow mechanics at the axial fan and the sound radiation can be analyzed. In addition, the replication of the flow fields of heat exchangers by the active turbulence grid is the focus of the investigations. The investigations showed that it is possible to use the active turbulence grid to generate defined inflow conditions for axial fans. It was also possible to reproduce the heat exchanger flow fields both for the mean turbulence values and for the spatial distributions. It was found that the grid induces tonal components due to the drive motors, but also that the inherent noise has no significant influence on the spectrum of the fans under investigation. Based on selected turbulence characteristics, direct correlations were found between the spatial distribution of the turbulence level and sound radiation at the first blade passing frequency of the axial fan. As the variance of the turbulence level increases, the sound radiation of the tonal components becomes more pronounced. The total sound pressure level, however, is mainly determined by the low-frequency broadband sound. A linear relationship between the spatial mean value of the turbulence level and the total sound pressure level was found for the investigated axial fan. |
| first_indexed | 2024-04-09T21:13:15Z |
| format | Article |
| id | doaj.art-a61ad9c325be46c18747ec4a233c8dd7 |
| institution | Directory Open Access Journal |
| issn | 2504-186X |
| language | English |
| last_indexed | 2024-04-09T21:13:15Z |
| publishDate | 2023-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | International Journal of Turbomachinery, Propulsion and Power |
| spelling | doaj.art-a61ad9c325be46c18747ec4a233c8dd72023-03-28T13:52:37ZengMDPI AGInternational Journal of Turbomachinery, Propulsion and Power2504-186X2023-01-0181110.3390/ijtpp8010001Active Turbulence Grid-Controlled Inflow Turbulence and Replication of Heat Exchanger Flow Fields in Fan ApplicationsFelix Czwielong0Stefan Becker1Institute for Fluid Mechanics, Friedrich-Alexander University Erlangen-Nuremberg, Cauerstr. 4, 91058 Erlangen, GermanyInstitute for Fluid Mechanics, Friedrich-Alexander University Erlangen-Nuremberg, Cauerstr. 4, 91058 Erlangen, GermanyA novel active turbulence grid of the Institute of Fluid Mechanics at FAU Erlangen-Nuremberg is introduced. The focus of this grid is not on basic investigations of fluid mechanics, as is usually the case with active turbulence grids, but the generation of defined inflow conditions for axial fans. Thus, by means of the active turbulence grid, individual turbulence characteristics in the flow to the fan can be changed; therefore, fundamental interactions between the flow mechanics at the axial fan and the sound radiation can be analyzed. In addition, the replication of the flow fields of heat exchangers by the active turbulence grid is the focus of the investigations. The investigations showed that it is possible to use the active turbulence grid to generate defined inflow conditions for axial fans. It was also possible to reproduce the heat exchanger flow fields both for the mean turbulence values and for the spatial distributions. It was found that the grid induces tonal components due to the drive motors, but also that the inherent noise has no significant influence on the spectrum of the fans under investigation. Based on selected turbulence characteristics, direct correlations were found between the spatial distribution of the turbulence level and sound radiation at the first blade passing frequency of the axial fan. As the variance of the turbulence level increases, the sound radiation of the tonal components becomes more pronounced. The total sound pressure level, however, is mainly determined by the low-frequency broadband sound. A linear relationship between the spatial mean value of the turbulence level and the total sound pressure level was found for the investigated axial fan.https://www.mdpi.com/2504-186X/8/1/1axial fan noiseactive turbulence gridheat exchangercontrolled inflowinflow turbulenceleading edge noise |
| spellingShingle | Felix Czwielong Stefan Becker Active Turbulence Grid-Controlled Inflow Turbulence and Replication of Heat Exchanger Flow Fields in Fan Applications International Journal of Turbomachinery, Propulsion and Power axial fan noise active turbulence grid heat exchanger controlled inflow inflow turbulence leading edge noise |
| title | Active Turbulence Grid-Controlled Inflow Turbulence and Replication of Heat Exchanger Flow Fields in Fan Applications |
| title_full | Active Turbulence Grid-Controlled Inflow Turbulence and Replication of Heat Exchanger Flow Fields in Fan Applications |
| title_fullStr | Active Turbulence Grid-Controlled Inflow Turbulence and Replication of Heat Exchanger Flow Fields in Fan Applications |
| title_full_unstemmed | Active Turbulence Grid-Controlled Inflow Turbulence and Replication of Heat Exchanger Flow Fields in Fan Applications |
| title_short | Active Turbulence Grid-Controlled Inflow Turbulence and Replication of Heat Exchanger Flow Fields in Fan Applications |
| title_sort | active turbulence grid controlled inflow turbulence and replication of heat exchanger flow fields in fan applications |
| topic | axial fan noise active turbulence grid heat exchanger controlled inflow inflow turbulence leading edge noise |
| url | https://www.mdpi.com/2504-186X/8/1/1 |
| work_keys_str_mv | AT felixczwielong activeturbulencegridcontrolledinflowturbulenceandreplicationofheatexchangerflowfieldsinfanapplications AT stefanbecker activeturbulencegridcontrolledinflowturbulenceandreplicationofheatexchangerflowfieldsinfanapplications |