考虑风攻角的硬跳线气动力系数和风偏计算

Calculation of aerodynamic coefficient and windage of hard jumper considering wind attack angle

采用风洞试验和有限元方法研究不同风攻角下硬跳线的气动力系数和风偏,分析各类硬跳线的阻力系数和升力系数随风速和风攻角的变化特征,给出不同风攻角下硬跳线气动力系数的建议值,提出了考虑山地风场影响的硬跳线体系风偏计算方法。研究表明:硬跳线的阻力系数随风速的增加而减小,而升力系数在高风速下基本不变;鼠笼式二分裂、四分裂、六分裂、八分裂和铝管式硬跳线在屏蔽效应最显著风攻角下阻力系数比最大值减少了53.4%、27.4%、25.1%、16.7%和57.4%;各类硬跳线在特定风攻角下均存在较大数值的升力系数;给出了各类硬跳线在不同风攻角下阻力系数和升力系数的建议值,阻力系数最大值可取1.17;水平风加速效应和风攻角对硬跳线的风偏响应有较大的影响,山顶位置风偏增大最显著。

Wind tunnel tests and finite element method were used to study aerodynamic coefficient and windage of hard jumper under different wind attack angles.Variation characteristics of drag coefficient and lift one of hard jumpers with varying of wind speed and wind attack angle were analyzed.The recommended values of aerodynamic coefficient of hard jumper under different wind attack angles were given,and the windage calculation method for hard jumper system considering effects of mountain wind field was proposed.The study showed that drag coefficient of hard jumper decreases with increase in wind speed,while its lift coefficient is basically unchanged under high wind speed;drag coefficients of hard jumpers of squirrel-cage types with 2-split,4-split,6-split,8-split and aluminum tube type under wind attack angles with the most significant shielding effect decrease by 53.4%,27.4%,25.1%,16.7%and 57.4%,respectively compared with their maximum values;all kinds of hard jumpers have larger lift coefficients under the specific wind attack angle;the recommended values of drag coefficients and lift coefficients of various hard jumpers under different wind attack angles were given,the maximum value of drag coefficient can be taken as 1.17;the horizontal wind acceleration effect and wind attack angle have larger influences on windage response of hard jumper,increase in windage at mountain top position is the most significant.