Wake structures and vortex induced vibration (VIV) of a spring-supported wide-D-section cylinder were experimentally investigated using an X-wire, a novel phase-locked particle image velocimetry (PIV), and an acce...Wake structures and vortex induced vibration (VIV) of a spring-supported wide-D-section cylinder were experimentally investigated using an X-wire, a novel phase-locked particle image velocimetry (PIV), and an acceleration sensor at a low speed wind tunnel. Compared with the fixed case, the 2P (two pair) vortex mode as defined by Govardhan and Williamson (2000) rather than S (single vortex) mode exists in the wake. The velocity deficit behind the cylinder is much larger than that of fixed case. The mean drag coefficient increases from 1.42 for the fixed case to 1.64 for the vibrating case. The Reynolds stress presents even distribution and small with increased distance of X/D = -2 to X/D = -10. The power spectra density based on accelerator and hot wire data presents a highlight identical. It shows that after a strong interaction the cylinder vibration and the vortex shedding come to a stable state. The vortex sheddin~ is totally locked on and controlled by the cylinder vihratinn.展开更多
针对成子河船闸需穿越多重水系,闸位选择受限因素多且引航道通航水流条件复杂的问题,船闸平面布置从水系连通、防洪规划、通航安全、对灌溉排涝的影响、船闸运营管理、征地拆迁和投资等多方面进行了技术经济比选。通过数模在引航道与上...针对成子河船闸需穿越多重水系,闸位选择受限因素多且引航道通航水流条件复杂的问题,船闸平面布置从水系连通、防洪规划、通航安全、对灌溉排涝的影响、船闸运营管理、征地拆迁和投资等多方面进行了技术经济比选。通过数模在引航道与上下游交叉河流处分别限定300、120 m 3 s最大安全通航流量条件,并采用疏浚拓挖增加过水断面和设置导流墙调整主流方向,改善了船闸引航道的通航水流条件。对复杂水系条件下的船闸闸位选择和平面布置有借鉴意义。展开更多
基金supported by the National Natural Science Foundation of China(11472158)
文摘Wake structures and vortex induced vibration (VIV) of a spring-supported wide-D-section cylinder were experimentally investigated using an X-wire, a novel phase-locked particle image velocimetry (PIV), and an acceleration sensor at a low speed wind tunnel. Compared with the fixed case, the 2P (two pair) vortex mode as defined by Govardhan and Williamson (2000) rather than S (single vortex) mode exists in the wake. The velocity deficit behind the cylinder is much larger than that of fixed case. The mean drag coefficient increases from 1.42 for the fixed case to 1.64 for the vibrating case. The Reynolds stress presents even distribution and small with increased distance of X/D = -2 to X/D = -10. The power spectra density based on accelerator and hot wire data presents a highlight identical. It shows that after a strong interaction the cylinder vibration and the vortex shedding come to a stable state. The vortex sheddin~ is totally locked on and controlled by the cylinder vihratinn.
文摘针对成子河船闸需穿越多重水系,闸位选择受限因素多且引航道通航水流条件复杂的问题,船闸平面布置从水系连通、防洪规划、通航安全、对灌溉排涝的影响、船闸运营管理、征地拆迁和投资等多方面进行了技术经济比选。通过数模在引航道与上下游交叉河流处分别限定300、120 m 3 s最大安全通航流量条件,并采用疏浚拓挖增加过水断面和设置导流墙调整主流方向,改善了船闸引航道的通航水流条件。对复杂水系条件下的船闸闸位选择和平面布置有借鉴意义。