基于CFD的赛艇阻力板空气动力性能数值模拟

目的:讨论一种在赛艇训练中增加训练阻力同时又不影响运动员技术动作的设备,即赛艇阻力器,在不同攻角、不同速度状态下,阻力、压力的变化,阻力与速度之间的关系以及增阻效果分析。方法:运用CFD软件FLUENT 6.2版本进行数值模拟。结果:速度不同,攻角相同状态下的阻力系数是相等的,阻力随速度和攻角的增大而增大,速度变化对阻力板阻力及压力的影响要大于角度的变化所产生的影响,阻力大小与速度的平方成正比,而阻力系数是常数。以155kg和175kg赛艇,阻力板攻角90°,赛艇划行速度5m/s为例,当无风状态时,安装阻力板的155kg赛艇增加的阻力(20.58N)比增加20kg重量(175kg)的阻力值(7.25N)大13.33N,增加的阻力值接近2倍。当顺风风速为3m/s时,阻力板增加的阻力为3.26N,比增加20kg重量的阻力值小3.99N,当逆风风速为3m/s时,阻力板增加的阻力为51.94N,比增加20kg重量增加的阻力值大44.69N,增加的阻力值近6倍多。结论:FLUENT软件对赛艇阻力板阻力计算是准确的,模拟的结果可以应用于具体的实际问题中。90°攻角状态下使用阻力板增加的阻力要优于由于赛艇艇重增加所达到的增阻效果。当处于顺风训练时,风速使阻力板增加的阻力值减小,减弱增阻效果,而逆风训练时,风速使阻力板产生的阻力值增大,加大了增阻效果。因此,采用阻力板训练,可以不改变赛艇的吃水和重心,保证运动员技术的完整性和连贯性,并且增加训练的强度,提高了训练的科学化水平。

The Simulation on the Resistance Plate of Rowing Based on CFD

In this article,one resistance plate is discussed,which has not affected the sports techniques and also can improve the resistance.There are also some analysis among resistance,pressures and velocities in the different attacked angles and velocities.Methods:the numerical simulation had been done using the software FlUENT 6.2,based on CFD.The resistances have been calculated in the different attacked angles.It can be seen from the simulation results that the resistance coefficients are the same under the situation of the same attacked angles and the different velocities.The variety of the velocity is much obvious than that of the attacked angles.When the angle attacked is increasing,the trends of the velocity increasing are more obvious.The resistance is referred to the square of the velocity.With the 90 attacked angles and velocity of 5 m/s,without winds,compared to the rowing weight between 155 kg and 175 kg,the resistance of the plate in 155 kg rowing is 13.33 N more than that of the adding 20 kg weight.The adding resistance is almost 2 times more than that of the weight adding.With the downwind 3 m/s,these no ascended about the resistance;with the upwind 3 m/s,the adding resistance of the plate is 44.69 N more.It is 6 times more than that of the adding 20 kg weight.It can be concluded that the drag coefficient is constant under the same attacked angle and the different velocity circumstances,while the resistance is proportional to the square of the velocity,so it is accurate that the FLUENT software for rowing resistance plate resistance calculation;the simulation results can be applied to a specific practical problems.In 90 attacked angles.The increased resistance of the resistance plate is superior to that of the rowing boat weight increasing.With the velocity increasing,the resistance is more.The resistance effect is best without changing the hull of the draft and the center of gravity.When training in the downwind,actual effect in the resistance plate is lower,when training in the upwind,it is helpful not only has the resistance plated,but also the aid of wind effect.It is very effective by using the resistance plate in this article.It can save time by the completion of the same amount of training.it also have the very practical value,thus which can improve the scientific level of training.