Suppression of the Karman vortex behind a circular cylinder by ON-OFF control using the pressure gradient
The Karman vortex generated in the flow field around bluff bodies has various negative effects on our daily lives. Therefore, control of the flow field has been studied for suppression of the Karman vortex. Recently, advanced control of the flow field has become possible by the development of fluid...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | Japanese |
| Published: |
The Japan Society of Mechanical Engineers
2024-12-01
|
| Series: | Nihon Kikai Gakkai ronbunshu |
| Subjects: | |
| Online Access: | https://www.jstage.jst.go.jp/article/transjsme/91/941/91_24-00195/_pdf/-char/en |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832584971894652928 |
|---|---|
| author | Yusho ISHIKAWA Itsuro HONDA Takao SATO |
| author_facet | Yusho ISHIKAWA Itsuro HONDA Takao SATO |
| author_sort | Yusho ISHIKAWA |
| collection | DOAJ |
| description | The Karman vortex generated in the flow field around bluff bodies has various negative effects on our daily lives. Therefore, control of the flow field has been studied for suppression of the Karman vortex. Recently, advanced control of the flow field has become possible by the development of fluid analysis technology and computers, and the method using feedback control has been attracting attention. The previous study using model predictive control has the disadvantage that the computational cost is enormous because iterative calculations are performed while predicting future responses. In addition, the previous study using feedback control with the flow velocity cannot completely suppress the vortex because time delay occurs between the time of the flow velocity and the time of control due to detecting the flow velocity behind the bluff body. Therefore, the conventional method can only be applied to flow fields where regular vortices are generated, and is considered impractical. To solve these problems, we propose a method of preventing the occurrence of vortices by controlling at the moment of separation by feedback the pressure gradient on the surface of the bluff body near the separation point. The use of the pressure gradient enables real time detection of separation by its sign, and thus enables control according to the occurrence of the vortex, which may be applicable to flow fields where vortices occur irregularly. In this report, we report the results of control of the flow field around a circular cylinder at low Reynolds number to confirm the effectiveness of the proposed method as a basic study for control in the flow field of high Reynolds number. According to the results of numerical calculation, the proposed method effectively suppresses the Karman vortex generated in the flow field of low to high Reynolds number, confirming the effectiveness of the proposed method. |
| format | Article |
| id | doaj-art-ffe6ce3271794a0ea3129a51544b1b1f |
| institution | Kabale University |
| issn | 2187-9761 |
| language | Japanese |
| publishDate | 2024-12-01 |
| publisher | The Japan Society of Mechanical Engineers |
| record_format | Article |
| series | Nihon Kikai Gakkai ronbunshu |
| spelling | doaj-art-ffe6ce3271794a0ea3129a51544b1b1f2025-01-27T08:34:35ZjpnThe Japan Society of Mechanical EngineersNihon Kikai Gakkai ronbunshu2187-97612024-12-019194124-0019524-0019510.1299/transjsme.24-00195transjsmeSuppression of the Karman vortex behind a circular cylinder by ON-OFF control using the pressure gradientYusho ISHIKAWA0Itsuro HONDA1Takao SATO2Graduate School of Engineering, University of HyogoGraduate School of Engineering, University of HyogoGraduate School of Engineering, University of HyogoThe Karman vortex generated in the flow field around bluff bodies has various negative effects on our daily lives. Therefore, control of the flow field has been studied for suppression of the Karman vortex. Recently, advanced control of the flow field has become possible by the development of fluid analysis technology and computers, and the method using feedback control has been attracting attention. The previous study using model predictive control has the disadvantage that the computational cost is enormous because iterative calculations are performed while predicting future responses. In addition, the previous study using feedback control with the flow velocity cannot completely suppress the vortex because time delay occurs between the time of the flow velocity and the time of control due to detecting the flow velocity behind the bluff body. Therefore, the conventional method can only be applied to flow fields where regular vortices are generated, and is considered impractical. To solve these problems, we propose a method of preventing the occurrence of vortices by controlling at the moment of separation by feedback the pressure gradient on the surface of the bluff body near the separation point. The use of the pressure gradient enables real time detection of separation by its sign, and thus enables control according to the occurrence of the vortex, which may be applicable to flow fields where vortices occur irregularly. In this report, we report the results of control of the flow field around a circular cylinder at low Reynolds number to confirm the effectiveness of the proposed method as a basic study for control in the flow field of high Reynolds number. According to the results of numerical calculation, the proposed method effectively suppresses the Karman vortex generated in the flow field of low to high Reynolds number, confirming the effectiveness of the proposed method.https://www.jstage.jst.go.jp/article/transjsme/91/941/91_24-00195/_pdf/-char/enpressure gradienton-off controlfeedback controlinjection and suction controlkarman vortex |
| spellingShingle | Yusho ISHIKAWA Itsuro HONDA Takao SATO Suppression of the Karman vortex behind a circular cylinder by ON-OFF control using the pressure gradient Nihon Kikai Gakkai ronbunshu pressure gradient on-off control feedback control injection and suction control karman vortex |
| title | Suppression of the Karman vortex behind a circular cylinder by ON-OFF control using the pressure gradient |
| title_full | Suppression of the Karman vortex behind a circular cylinder by ON-OFF control using the pressure gradient |
| title_fullStr | Suppression of the Karman vortex behind a circular cylinder by ON-OFF control using the pressure gradient |
| title_full_unstemmed | Suppression of the Karman vortex behind a circular cylinder by ON-OFF control using the pressure gradient |
| title_short | Suppression of the Karman vortex behind a circular cylinder by ON-OFF control using the pressure gradient |
| title_sort | suppression of the karman vortex behind a circular cylinder by on off control using the pressure gradient |
| topic | pressure gradient on-off control feedback control injection and suction control karman vortex |
| url | https://www.jstage.jst.go.jp/article/transjsme/91/941/91_24-00195/_pdf/-char/en |
| work_keys_str_mv | AT yushoishikawa suppressionofthekarmanvortexbehindacircularcylinderbyonoffcontrolusingthepressuregradient AT itsurohonda suppressionofthekarmanvortexbehindacircularcylinderbyonoffcontrolusingthepressuregradient AT takaosato suppressionofthekarmanvortexbehindacircularcylinderbyonoffcontrolusingthepressuregradient |