Drag Reduction of Non-Circular Cylinder at Subcritical Reynolds Numbers
Experimental and numerical investigation of fore body geometrical effects on drag and flow-field of non-circular cylinder ( D-shaped bluff body) were conducted in the subcritical flow regime at Reynolds number in the range of 1 x 105 ≤ Re ≤ 1.8 x 105. To shield the non circular cylinder ( D-shaped m...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Isfahan University of Technology
2019-01-01
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| Series: | Journal of Applied Fluid Mechanics |
| Subjects: | |
| Online Access: | http://jafmonline.net/JournalArchive/download?file_ID=48135&issue_ID=253 |
| _version_ | 1818231652085661696 |
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| author | V. Suresh P. S. Premkumar C. Senthil Kumar |
| author_facet | V. Suresh P. S. Premkumar C. Senthil Kumar |
| author_sort | V. Suresh |
| collection | DOAJ |
| description | Experimental and numerical investigation of fore body geometrical effects on drag and flow-field of non-circular cylinder ( D-shaped bluff body) were conducted in the subcritical flow regime at Reynolds number in the range of 1 x 105 ≤ Re ≤ 1.8 x 105. To shield the non circular cylinder ( D-shaped model ) front surface from the positive pressure of the unsteady vortex generation in the near wake, circular disk of various geometries were attached upstream of the non-circular cylinder base model. The fore body makes the streamlines that separate from its edges to attach smoothly onto the front face shoulders of the main body, thereby converting the bluff body into an equivalent streamlined body to result in low drag. The diameter of the fore body (b1) ranges from 0.25 to 0.75 times the hydraulic diameter of base model ( b2 ) and the gap ratio ( g/ b2 ),was in the range from 0.25 to 1.75 b2. The experimental and numerical investigations show that by using a circular disk as fore body with a width ratio b1/b2 of 0.75 and a gap ratio of g/ b2 = 0.75 results in a configuration having percentage drag reduction of about 67 % and 65 % respectively. |
| first_indexed | 2024-12-12T10:53:47Z |
| format | Article |
| id | doaj.art-1772a62562a34427a8598b0e6c05a756 |
| institution | Directory Open Access Journal |
| issn | 1735-3572 |
| language | English |
| last_indexed | 2024-12-12T10:53:47Z |
| publishDate | 2019-01-01 |
| publisher | Isfahan University of Technology |
| record_format | Article |
| series | Journal of Applied Fluid Mechanics |
| spelling | doaj.art-1772a62562a34427a8598b0e6c05a7562022-12-22T00:26:43ZengIsfahan University of TechnologyJournal of Applied Fluid Mechanics1735-35722019-01-01121187194.Drag Reduction of Non-Circular Cylinder at Subcritical Reynolds NumbersV. Suresh0P. S. Premkumar1C. Senthil Kumar2Department of Aerospace Engineering, M.I.T Campus, Anna University, Chennai, 600044, IndiaDepartment of Aeronautical Engineering, Kumaraguru College of Technology, Coimbatore, 641049, IndiDepartment of Aerospace Engineering, Madras Institute of Technology, Anna University, Tamil Nadu,Experimental and numerical investigation of fore body geometrical effects on drag and flow-field of non-circular cylinder ( D-shaped bluff body) were conducted in the subcritical flow regime at Reynolds number in the range of 1 x 105 ≤ Re ≤ 1.8 x 105. To shield the non circular cylinder ( D-shaped model ) front surface from the positive pressure of the unsteady vortex generation in the near wake, circular disk of various geometries were attached upstream of the non-circular cylinder base model. The fore body makes the streamlines that separate from its edges to attach smoothly onto the front face shoulders of the main body, thereby converting the bluff body into an equivalent streamlined body to result in low drag. The diameter of the fore body (b1) ranges from 0.25 to 0.75 times the hydraulic diameter of base model ( b2 ) and the gap ratio ( g/ b2 ),was in the range from 0.25 to 1.75 b2. The experimental and numerical investigations show that by using a circular disk as fore body with a width ratio b1/b2 of 0.75 and a gap ratio of g/ b2 = 0.75 results in a configuration having percentage drag reduction of about 67 % and 65 % respectively.http://jafmonline.net/JournalArchive/download?file_ID=48135&issue_ID=253D-shaped model; Pressure drag; Shielding effect; CFD; Fore body geometry; Drag reduction. |
| spellingShingle | V. Suresh P. S. Premkumar C. Senthil Kumar Drag Reduction of Non-Circular Cylinder at Subcritical Reynolds Numbers Journal of Applied Fluid Mechanics D-shaped model; Pressure drag; Shielding effect; CFD; Fore body geometry; Drag reduction. |
| title | Drag Reduction of Non-Circular Cylinder at Subcritical Reynolds Numbers |
| title_full | Drag Reduction of Non-Circular Cylinder at Subcritical Reynolds Numbers |
| title_fullStr | Drag Reduction of Non-Circular Cylinder at Subcritical Reynolds Numbers |
| title_full_unstemmed | Drag Reduction of Non-Circular Cylinder at Subcritical Reynolds Numbers |
| title_short | Drag Reduction of Non-Circular Cylinder at Subcritical Reynolds Numbers |
| title_sort | drag reduction of non circular cylinder at subcritical reynolds numbers |
| topic | D-shaped model; Pressure drag; Shielding effect; CFD; Fore body geometry; Drag reduction. |
| url | http://jafmonline.net/JournalArchive/download?file_ID=48135&issue_ID=253 |
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