莊林學(xué) 原世紀(jì) 馬丁 劉春



摘?要:使用CFD軟件求解定常不可壓縮流動的時均N-S方程和SST k-ω湍流模型,分別數(shù)值模擬了進(jìn)口流速10m/s下維式和五次方收縮曲線的流場。計算結(jié)果表明,維式曲線從入口部分快速收縮,接近出口收縮慢,使其在速度均勻性和軸向壓力梯度等方面優(yōu)于五次方曲線,然而由于更早的達(dá)到較大速度,維式曲線的總壓損失系數(shù)相對五次方曲線增大22.6%。
關(guān)鍵詞:風(fēng)能;收縮曲線;流場特性;數(shù)值模擬
中圖分類號:V211??文獻(xiàn)標(biāo)識碼:A
Numerical Simulation of Flow Field for Two Typical Contraction Curves
Zhuang Linxue1?Yuan Shiji2?Ma Ding1?Liu Chun1
1.School of aeronautics and astronautics,Shenyang Aerospace University?LiaoningShenyang?110136;
2.School of electronic and information engineering,Shenyang Aerospace University?LiaoningShenyang?110136
Abstract:The flow fields of Witozinsky curve and fifth degree polynomial curve are simulated at inlet velocity of 10m/s,based on time-averaged N-S equation of steady incompressible flow and SST k-ω turbulence model solved by CFD software.The results show that the Witozinsky curve contracts rapidly from the inlet and slowly near the outlet,which makes it superior to fifth degree polynomial curve on velocity uniformity and axial pressure gradient.However,the total pressure loss coefficient of Witozinsky curve increases by 22.6%,compared to fifth degree polynomial curve,due to earlier emergence of relatively high velocity.
Key words:wind energy;contraction curve;flow field;numerical simulation
隨著城鎮(zhèn)化的迅猛發(fā)展,城市對于能源的需求與日俱增,積極利用城市風(fēng)資源是緩解能源與環(huán)境問題的有效途徑之一[1-2]。風(fēng)力機(jī)的功率與來流風(fēng)速的立方成之比,風(fēng)速的略微提高能夠引起功率的大幅度的增大。因此,通過集風(fēng)罩集風(fēng)效應(yīng)提高機(jī)風(fēng)力來流的速度是提高風(fēng)力機(jī)功率的有效措施,傳統(tǒng)的集風(fēng)罩一般由收縮段和擴(kuò)張段組成。目前,針對收縮曲線氣動設(shè)計、性能評估及流場的研究主要集中在風(fēng)洞和水洞等流體測試設(shè)備領(lǐng)域。李國文[3]介紹一種UG參數(shù)化收縮曲線設(shè)計方法,經(jīng)試驗和計算標(biāo)明該曲線流暢品質(zhì)優(yōu)良。吳宗成[4]介紹了一種水洞非對稱收縮段的數(shù)值模擬方法,并結(jié)合水洞設(shè)計對集中典型收縮曲線三維流場進(jìn)行了計算和分析。李海燕[5]采用FLUENT軟件對雙三次曲線和維氏曲線進(jìn)行了數(shù)值模擬,從速度和靜壓圖中可以看出雙三次曲線的流場品質(zhì)更好。王帥[6]等針對直流式低速風(fēng)洞收縮段對不同類型的收縮曲線仿真,綜合比較了氣流的動壓系數(shù)、速度不均勻度和軸向靜壓梯度等特性?!?br>