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船舶螺旋槳水動力及空泡性能的預(yù)測

發(fā)布時間:2019-05-21 23:16
【摘要】:螺旋槳因其優(yōu)良的性能,是目前船舶領(lǐng)域使用最普遍的推進(jìn)器。海上運輸和軍用艦船發(fā)展日益繁榮的現(xiàn)代社會,各種新型船和高性能船相繼出現(xiàn),船舶發(fā)展趨于大型化、高速化。隨著船舶主機不斷往高轉(zhuǎn)速和大功率發(fā)展,空泡引起的槳舵剝蝕、螺旋槳噪聲和船舶振動問題變得日益突出。流體的空化是一種復(fù)雜的物理現(xiàn)象,涉及到相變、表面張力、湍流、非均勻熱力學(xué)效應(yīng)等問題?栈部烧J(rèn)為是在一定溫度下由于水動力學(xué)壓力的減小引起的液體的相變的流體流動現(xiàn)象?栈輹(jīng)歷發(fā)生、潰滅,其過程是迅速且劇烈的,從而會導(dǎo)致腐蝕、震動、噪聲。本文圍繞螺旋槳的水動力性能和空化問題展研究,主要的工作有: 詳細(xì)地描述了螺旋槳的幾何參數(shù),提出了切面數(shù)據(jù)的生成方法,利用NURBS曲線擬合槳葉切面,再由擬合的曲線生成蒙皮NURBS曲面,最后總結(jié)提出了參數(shù)化建模方法及其基本工作流程。 采用了單方程Spalart-Allmaras模型和兩方程k-ε RNG模型、 k-ω SST三個典型的湍流模型對二維水翼(NACA66mod)的空化進(jìn)行了計算。結(jié)果表明SST湍流模型能模擬出空泡流的更多細(xì)節(jié)特征,比如可以觀察到明顯回射流,再對比了Zwart-Gerber-Belamri和Schnerr-Sauer空化模型,發(fā)現(xiàn)后者具有更高的精度和適應(yīng)性。 在基于LES方法的二維水翼動態(tài)空泡流的模擬中,得到了典型的片狀空泡脫落過程,空泡脫落周期為0.29比較接近0.28的試驗值,,空泡閉合區(qū)的回射流是導(dǎo)致空泡脫落的主要原因,而渦結(jié)構(gòu)則影響脫落空泡的形態(tài)。 對螺旋槳全濕流和空泡流水動力性能計算中發(fā)現(xiàn)兩者的結(jié)果十分吻合,說明局部空泡不影響槳旋槳的宏觀水動力性能。在全流道和單流道模擬中,水動力性能與試驗值的誤差在8%以內(nèi),全流道計算的推力系數(shù)和扭矩系數(shù)與試驗的誤差比單流道計算的較小,但是單流道得到空化區(qū)大小更接近試驗。
[Abstract]:Propeller is the most commonly used thruster in ship field because of its excellent performance. In the modern society with the increasingly prosperous development of maritime transportation and military ships, all kinds of new ships and high-performance ships have emerged one after another, and the development of ships tends to be large-scale and high-speed. With the development of high speed and high power of ship main engine, the problems of propeller rudder denudation, propeller noise and ship vibration caused by cavitation have become more and more prominent. Cavitation of fluid is a complex physical phenomenon, which involves phase transition, surface tension, turbulence, inhomogeneous thermodynamic effect and so on. Cavitation can also be considered to be the fluid flow phenomenon of liquid phase transition caused by the decrease of hydrodynamic pressure at a certain temperature. Cavitation bubbles will experience occurrence and collapse, the process is rapid and violent, which will lead to corrosion, vibration, noise. In this paper, the hydrodynamic performance and cavitation of propellers are studied. The main work is as follows: the geometric parameters of propellers are described in detail, the generation method of section data is put forward, and the blade section is fitted by NURBS curve. Then the skinned NURBS surface is generated from the fitted curve. Finally, the parametric modeling method and its basic work flow are summarized. The cavitation of two-dimensional hydrofoil (NACA66mod) is calculated by using three typical turbulence models: single-equation Spalart-Allmaras model and two-equation k-蔚 RNG model and k-蠅 SST model. The results show that the SST turbulence model can simulate more details of the bubble flow, such as the obvious return jet can be observed, and then the Zwart-Gerber-Belamri and Schnerr-Sauer cavitation models are compared, and it is found that the latter has higher accuracy and adaptability. In the simulation of dynamic cavitation flow of two-dimensional hydrofoil based on LES method, a typical flake cavitation shedding process is obtained. the experimental value of cavitation shedding period of 0.29 is close to 0.28. The backjet in the closed zone of cavitation is the main cause of cavitation shedding, while the vortex structure affects the morphology of falling cavitation. It is found that the results of the total wet flow and the cavitation flow dynamic performance of the propeller are in good agreement with each other, which indicates that the local cavitation does not affect the macroscopic hydrodynamic performance of the propeller. In the simulation of full channel and single channel, the error between hydrodynamic performance and test value is less than 8%, and the error between thrust coefficient and torque coefficient calculated by full channel and test is smaller than that calculated by single channel. However, the size of cavitation zone obtained by single channel is closer to the test.
【學(xué)位授予單位】:重慶大學(xué)
【學(xué)位級別】:碩士
【學(xué)位授予年份】:2014
【分類號】:U664.33;U661.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 李廣年;張國平;陸林章;洪方文;張軍;;大型空泡水筒中螺旋槳尾流場2D-PIV測量[J];船舶力學(xué);2009年05期

2 劉艷;趙鵬飛;周力;陳朝暉;;RANS方法和升力面理論預(yù)報螺旋槳敞水性能比較研究[J];大連理工大學(xué)學(xué)報;2010年06期

3 吳梵,陳昕;噴水推進(jìn)裝置及其在艦艇上的應(yīng)用[J];海軍工程大學(xué)學(xué)報;2003年06期

4 鄭巢生;張志榮;;基于OpenFOAM的螺旋槳敞水性能預(yù)報方法[J];中國艦船研究;2012年03期

5 閻超;于劍;徐晶磊;范晶晶;高瑞澤;姜振華;;CFD模擬方法的發(fā)展成就與展望[J];力學(xué)進(jìn)展;2011年05期

6 李向賓;王國玉;張敏弟;劉淑艷;;繞水翼超空化流動形態(tài)與速度分布[J];力學(xué)學(xué)報;2008年03期

7 葉劍平;莊光宇;;螺旋槳水動力性能計算粘性流體CFD方法的應(yīng)用與研究[J];艦船科學(xué)技術(shù);2013年04期

8 唐登海,董世湯;船舶螺旋槳周圍粘流場數(shù)值預(yù)報與流場分析[J];水動力學(xué)研究與進(jìn)展(A輯);1997年04期

9 沈海龍;蘇玉民;;船體黏性非均勻伴流場中螺旋槳非定常水動力性能預(yù)報研究[J];水動力學(xué)研究與進(jìn)展A輯;2009年02期

10 錢忠東;黃社華;;四種湍流模型對空化流動模擬的比較[J];水科學(xué)進(jìn)展;2006年02期



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