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近距离并列吊索和并列斜拉索在大跨度缆索承重桥中有广泛的应用,但目前在计算并列索静力风荷载时只考虑顺风向阻力的影响,没有考虑因尾流干扰所产生的横风向升力的作用。通过风洞试验,在雷诺数Re=0.9×105~4.6×105(涉及亚临界雷诺数区和临界雷诺数区)研究了多种不同相对位置的并列双圆柱的平均阻力、平均升力和斯特罗哈数随雷诺数的变化规律。研究结果表明:并列圆柱的平均气动性能有强烈的雷诺数效应,临界雷诺数下的气动力系数与亚临界区有很大的差异;在临界雷诺数区域,下游圆柱的平均升力系数会随雷诺数的增大发生不连续突变,这种气动力的突变很可能与双圆柱绕流场的流态结构的演变有关;受上游圆柱的尾流干扰,在临界雷诺数区域内下游圆柱的平均升力系数可达到1.25以上,远大于下游圆柱的平均阻力系数,因而在计算并列索静力风荷载时有必要考虑横风向平均升力的作用。
Short-distance juxtaposed slings and juxtaposed stay cables are widely used in long-span cable-bearing bridges. However, only the effects of downwind resistance are considered in the calculation of parallel static wind loads, and the effects of wake disturbance are not considered The role of cross-wind lift. Through the wind tunnel test, the average drag, the average lift and the average drag of parallel double cylinders with different relative positions were studied at Reynolds number Re = 0.9 × 105 ~ 4.6 × 105 (involving the subcritical Reynolds number region and the critical Reynolds number region) Variation of Loh number with Reynolds number. The results show that the average aerodynamic properties of the parallel cylinders have a strong Reynolds number effect, and the aerodynamic coefficients at the critical Reynolds number are quite different from the subcritical ones. In the critical Reynolds number region, the average lift coefficient of the downstream cylinder will vary with the Reynolds number The discontinuity in the increase of the number is likely to occur. This sudden change in aerodynamics is likely to be related to the evolution of the fluid structure of the double-cylinder around the flow field. The average lift of the downstream cylinder in the critical Reynolds number zone due to wake disturbance of the upstream cylinder Coefficient can reach more than 1.25, which is much larger than the average drag coefficient of the downstream cylinder. Therefore, it is necessary to consider the effect of the average cross-wind lift when calculating the static wind load.