TY - JOUR
T1 - CFD analysis of flow-induced rotation of a circular cylinder with a detached rear splitter plate in laminar flow
AU - Tang, Tao
AU - Zhu, Hongjun
AU - Chen, Quanyu
AU - Li, Guomin
AU - Zhou, Tongming
N1 - Funding Information:
This research was supported by the National Natural Science Foundation of China (Grant No. 51979238 ). The work was carried out in the computer cluster of the laboratory of offshore oil and gas engineering at Southwest Petroleum University (SWPU).
Funding Information:
This research was supported by the National Natural Science Foundation of China (Grant No. 51979238). The work was carried out in the computer cluster of the laboratory of offshore oil and gas engineering at Southwest Petroleum University (SWPU).
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2022/12/15
Y1 - 2022/12/15
N2 - This paper numerically investigated the flow-induced rotation response of an elastically mounted circular cylinder fitted with a detached rear splitter plate in laminar flow. With the help of ANSYS-FLUENT, the fluid governing equations were solved with the finite volume method, and the fluid-structure interaction was achieved with user-defined functions. Three different gap ratios of G* = 0, 0.25, and 0.5 were examined in the computations that carried out for a reduced velocity range of Ur = 3–18. For the typical case of G* = 0.25, a symmetry-breaking bifurcation, i.e., the structure's equilibrium position deflects to a position which is not parallel to the free stream, occurs at Ur > 15. Before bifurcation, there is only one stable flapping motion. However, two extra rotary processes are observed when bifurcation appears, including a negatively-directional deflection and the 2nd flapping motion. For G* = 0, the bifurcation is found at Ur > 12, while it is absent for G* = 0.5. The varying tendencies of the root-mean-squared rotary angle for all considered cases show a VIV rotary response. The smaller gap distance leads to the larger rotary angles at Ur ≤ 12, while the opposite tendency is observed at Ur > 12. The hydrodynamic coefficients of the rotary cylinder-plate body are significantly reduced, as compared with a bare cylinder. The drag- and lift-reduction are mainly due to the recovery of base pressure behind the cylinder and the delayed vortex formation. The global vortex shedding is identified to be 2S mode for both cases with and without bifurcation, although the vortex formation and the shedding pattern in the near wake vary with gap distance and reduced velocity. Due to the deflection, reattachment behavior is more likely to appear and its position shifts from the plate surface or tail to the leading edge of the splitter plate with increasing gap ratio.
AB - This paper numerically investigated the flow-induced rotation response of an elastically mounted circular cylinder fitted with a detached rear splitter plate in laminar flow. With the help of ANSYS-FLUENT, the fluid governing equations were solved with the finite volume method, and the fluid-structure interaction was achieved with user-defined functions. Three different gap ratios of G* = 0, 0.25, and 0.5 were examined in the computations that carried out for a reduced velocity range of Ur = 3–18. For the typical case of G* = 0.25, a symmetry-breaking bifurcation, i.e., the structure's equilibrium position deflects to a position which is not parallel to the free stream, occurs at Ur > 15. Before bifurcation, there is only one stable flapping motion. However, two extra rotary processes are observed when bifurcation appears, including a negatively-directional deflection and the 2nd flapping motion. For G* = 0, the bifurcation is found at Ur > 12, while it is absent for G* = 0.5. The varying tendencies of the root-mean-squared rotary angle for all considered cases show a VIV rotary response. The smaller gap distance leads to the larger rotary angles at Ur ≤ 12, while the opposite tendency is observed at Ur > 12. The hydrodynamic coefficients of the rotary cylinder-plate body are significantly reduced, as compared with a bare cylinder. The drag- and lift-reduction are mainly due to the recovery of base pressure behind the cylinder and the delayed vortex formation. The global vortex shedding is identified to be 2S mode for both cases with and without bifurcation, although the vortex formation and the shedding pattern in the near wake vary with gap distance and reduced velocity. Due to the deflection, reattachment behavior is more likely to appear and its position shifts from the plate surface or tail to the leading edge of the splitter plate with increasing gap ratio.
KW - Bifurcation
KW - Detached splitter plate
KW - Flow-induced rotation
KW - Gap distance
KW - Laminar flow
KW - Reduced velocity
UR - http://www.scopus.com/inward/record.url?scp=85139306994&partnerID=8YFLogxK
U2 - 10.1016/j.oceaneng.2022.112703
DO - 10.1016/j.oceaneng.2022.112703
M3 - Article
AN - SCOPUS:85139306994
SN - 0029-8018
VL - 266
JO - Ocean Engineering
JF - Ocean Engineering
M1 - 112703
ER -