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## Numerical Study of Flow Stabilization Mechanism of Stepped-Nosed Obstacle

#### K. M. Rahman [1] , M. Mashud [2]

##### 130 348

A rectangular obstacle the front corners of which are deformed in step form (called “stepped nosed obstacle”) may experience a much smaller drag force and lift force fluctuation. The underlying physics of this drag reduction and flow stabilization mechanism are explored in numerical and theoretical approaches. In the optimal step configuration that the flow separating from the front surface edges reattaches smoothly at the leading edge of the main body’s side surface. (1) The pressure drag force acting on the forebody almost vanishes because the strong vortices trapped in the stepped corners produce the thrust force which cancel the drag force acting on the front surface, and (2) The oscillation of lift force acting on the obstacle is largely suppressed and the scale of the Karman vortices is reduced because the large scale of the separated flow over the side surface is suppressed. The step size which brings about such optimal step flow condition is identified and the dependences of various flow characteristics on the step size are discussed in detail, which will be useful to consider another drag reduction treatment than streamlining the profile of obstacle in engineering application
Drag Reduction, Numerical Simulation, Rectangular body, and Stepped nosed
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Other ID JA65KH88RT Articles Author: K. M. RahmanInstitution: Department of Mechanical Engineering Khulna University of Engineering & Technology (KUET) Khulna-9203, Bangladesh Author: M. MashudInstitution: Department of Mechanical Engineering Khulna University of Engineering & Technology (KUET) Khulna-9203, Bangladesh Publication Date: December 1, 2010
 Bibtex @ { ijeas251144, journal = {International Journal of Engineering and Applied Sciences}, issn = {}, eissn = {1309-0267}, address = {Akdeniz University}, year = {2010}, volume = {2}, pages = {83 - 92}, doi = {}, title = {Numerical Study of Flow Stabilization Mechanism of Stepped-Nosed Obstacle}, key = {cite}, author = {Rahman, K. M. and Mashud, M.} } APA Rahman, K , Mashud, M . (2010). Numerical Study of Flow Stabilization Mechanism of Stepped-Nosed Obstacle. International Journal of Engineering and Applied Sciences, 2 (4), 83-92. Retrieved from http://dergipark.org.tr/ijeas/issue/23576/251144 MLA Rahman, K , Mashud, M . "Numerical Study of Flow Stabilization Mechanism of Stepped-Nosed Obstacle". International Journal of Engineering and Applied Sciences 2 (2010): 83-92 Chicago Rahman, K , Mashud, M . "Numerical Study of Flow Stabilization Mechanism of Stepped-Nosed Obstacle". International Journal of Engineering and Applied Sciences 2 (2010): 83-92 RIS TY - JOUR T1 - Numerical Study of Flow Stabilization Mechanism of Stepped-Nosed Obstacle AU - K. M. Rahman , M. Mashud Y1 - 2010 PY - 2010 N1 - DO - T2 - International Journal of Engineering and Applied Sciences JF - Journal JO - JOR SP - 83 EP - 92 VL - 2 IS - 4 SN - -1309-0267 M3 - UR - Y2 - 2019 ER - EndNote %0 International Journal of Engineering and Applied Sciences Numerical Study of Flow Stabilization Mechanism of Stepped-Nosed Obstacle %A K. M. Rahman , M. Mashud %T Numerical Study of Flow Stabilization Mechanism of Stepped-Nosed Obstacle %D 2010 %J International Journal of Engineering and Applied Sciences %P -1309-0267 %V 2 %N 4 %R %U ISNAD Rahman, K. M. , Mashud, M. . "Numerical Study of Flow Stabilization Mechanism of Stepped-Nosed Obstacle". International Journal of Engineering and Applied Sciences 2 / 4 (December 2010): 83-92. AMA Rahman K , Mashud M . Numerical Study of Flow Stabilization Mechanism of Stepped-Nosed Obstacle. IJEAS. 2010; 2(4): 83-92. Vancouver Rahman K , Mashud M . Numerical Study of Flow Stabilization Mechanism of Stepped-Nosed Obstacle. International Journal of Engineering and Applied Sciences. 2010; 2(4): 92-83.