中山大学学报(自然科学版)
中山大學學報(自然科學版)
중산대학학보(자연과학판)
ACTA SCIENTIARUM NATURALIUM UNIVERSITATIS SUNYATSENI
2014年
4期
142-148
,共7页
底边界层%湍流%高斯白噪声%线性趋势项%周期项
底邊界層%湍流%高斯白譟聲%線性趨勢項%週期項
저변계층%단류%고사백조성%선성추세항%주기항
bottom boundary layer%turbulence%white Gaussian noise%linear trend%periodic signal
基于河口底边界层实测湍流资料,选取了高斯白噪声、线性趋势项和周期项3种不同类型的噪声,讨论了各种噪声对湍流信号的影响。结果表明:①3种类型的噪声对湍流信号的概率分布影响不大,但对能谱曲线有较显著的影响。其中,白噪声对能谱值的影响最大,趋势项对能谱值的影响不明显,周期项仅对特定频率的能谱值有影响。②对于湍流强度、脉动能量和湍动能耗散率这3个湍流特征参数,白噪声和周期项对3种参数均有影响,而趋势项仅对湍强和脉动能量有影响。当湍流信号叠加上3种类型的噪声后,会使湍流特征参数有增大的趋势。
基于河口底邊界層實測湍流資料,選取瞭高斯白譟聲、線性趨勢項和週期項3種不同類型的譟聲,討論瞭各種譟聲對湍流信號的影響。結果錶明:①3種類型的譟聲對湍流信號的概率分佈影響不大,但對能譜麯線有較顯著的影響。其中,白譟聲對能譜值的影響最大,趨勢項對能譜值的影響不明顯,週期項僅對特定頻率的能譜值有影響。②對于湍流彊度、脈動能量和湍動能耗散率這3箇湍流特徵參數,白譟聲和週期項對3種參數均有影響,而趨勢項僅對湍彊和脈動能量有影響。噹湍流信號疊加上3種類型的譟聲後,會使湍流特徵參數有增大的趨勢。
기우하구저변계층실측단류자료,선취료고사백조성、선성추세항화주기항3충불동류형적조성,토론료각충조성대단류신호적영향。결과표명:①3충류형적조성대단류신호적개솔분포영향불대,단대능보곡선유교현저적영향。기중,백조성대능보치적영향최대,추세항대능보치적영향불명현,주기항부대특정빈솔적능보치유영향。②대우단류강도、맥동능량화단동능모산솔저3개단류특정삼수,백조성화주기항대3충삼수균유영향,이추세항부대단강화맥동능량유영향。당단류신호첩가상3충류형적조성후,회사단류특정삼수유증대적추세。
In this paper , the effect of various noises on the turbulence was discussed based on the field observation data in estuarine bottom boundary layer , and choosing three kinds of noise , the white Gaussi-an noise , the linear trend , and the periodic signal .The following results have been obtained:( 1 ) The energy spectrum of the turbulence is more obviously affected than the probability distribution .The influ-ence of white Gaussian noise on the energy spectrum is the largest , the influence of linear trend is not no-table, and the periodic signal only makes effects on specific frequency .(2) White Gaussian noise and periodic signal both have influence on these three turbulent parameters:turbulent intensity , turbulent en-ergy and turbulent energy dissipation rate , but the linear trend only has influence on turbulent intensity and turbulent energy .Adding noises to the turbulence will make the turbulent parameters increase .