文章快速检索 高级检索

Performance comparison of accelerating duct and decelerating duct
HU Jian, WANG Nan, HU Yang
School of Shipbuilding Engineering, Harbin Engineering University, Harbin 150001, China
Received: 2016-02-25; Accepted: 2016-06-13; Published online: 2016-09-06 15:39
Foundation item: National Natural Science Foundation of China (11302057, 51579052)
Corresponding author. HU Jian, E-mail:hujian791018@163.com
Abstract: In order to study the loading characteristics of different forms of ducted propellers, this paper analyzes the hydrodynamic performance of accelerating duct and decelerating duct and their influences on propellers by using computational fluid dynamics (CFD) method. The computation domain is divided into two parts:cylindrical domain containing the propeller and outer domain containing the duct. The computation domain is discretized by using fully structured gridding technique to optimize the quality of grids and improve the accuracy of calculation. The continuity of physical quantities such as fluid velocity and pressure between different domains is guaranteed by using the interface technique. This paper analyzes the hydrodynamic performance of JD7704+Ka4-5508 first, and the according results are compared with those by experiments to verify the rationality of the model and the grids technique. On this basis, this paper analyzes the hydrodynamic performance of accelerating duct and decelerating duct with varied cambers and angles of attack, and their influences on the loading state of propellers. The study shows that the accelerating duct and decelerating duct due to the variation of the cambers and angles of attack have different hydrodynamic performance, and they can optimize the propeller's operating conditions and loading characteristics greatly.
Key words: ducted propeller     accelerating duct     decelerating duct     computational fluid dynamics (CFD)     hydrodynamic performance

1 基本原理 1.1 湍流运动控制方程

1.1.1 连续性方程

 (1)

 (2)

 (3)

 (4)

1.1.2 动量守恒方程

 (5)

1.2 控制方程的离散化

1.2.1 离散方法

1) 有限差分法

2) 有限元法

3) 有限体积法

1.2.2 离散格式

1) 一阶迎风格式

2) 指数格式

3) 中心差分格式

4) QUICK格式

QUICK格式是一种改进的离散方法，它对对流项采用二次插值格式。与中心差分格式相同，QUICK格式的应用范围受到稳定性条件的限制，要求对流与扩散的强度之比不大于8/3。因为QUICK格式具有减少假扩散误差和计算精度高的优点，应用比较广泛，但主要用于六面体和四边形网格。

2 数值模型的建立 2.1 计算模型及网格划分

 参数 数值/m 长度 0.1665 导管外径 0.34 导管内径 0.30 叶梢间距 0.026

 参数 数值 直径/m 0.25 盘面比 0.55 毂径比 0.2 螺距比 0.8 桨叶数 4

 图 1 导管桨三维模型 Fig. 1 Three-dimensional model of ducted propeller

 图 2 旋转域网格示意图 Fig. 2 Meshing sketch of rotating domain

 图 3 流体域网格划分 Fig. 3 Meshing of fluid domain
 图 4 导管桨表面网格划分 Fig. 4 Meshing over surfaces of ducted propeller
2.2 边界条件

 数值方法 计算模型 求解器 三维单精度基于压力的定常隐式求解器 湍流模型 SST k-ω 运动模式 MRF 水的密度/(kg·m-3) 998.2 水的动力黏性系数/(kg·(m·s)-1) 0.001003 螺旋桨转速/(r·min-1) 600 入口速度/(m·s-1) 1.25 压力离散格式 Standard 耦合方式 SIMPLEC 差分方式 一阶迎风格式

3 验证

 图 5 JD7704+Ka4-5508型导管桨敞水特性的计算值与试验值比较 Fig. 5 Comparison of numerical and test results of JD7704+Ka4-5508 ducted propeller's open water characteristics

 (6)

 (7)

 (8)

 (9)

 (10)

4 加速、减速导管桨水动力特性分析

 图 6 拱度为-0.75 t、0和0.75 t时导管翼形剖面示意图 Fig. 6 Schematic diagram of duct's airfoil sections as f=-0.75 t, f=0, and f=0.75 t
4.1 改变导管翼形剖面拱度

NACA0012翼形剖面的初始拱度f为0。按照局部剖面厚度t的百分比来改变其拱度。在图 6中，f=0.75 t表示导管外拱，其局部拱度f是局部厚度的0.75倍。本节共计算了7种情况，导管翼形剖面拱度分别为-0.75 t、-0.50 t、-0.25 t、0、0.25 t、0.50 t、0.75 t。以拱度分别为-0.75 t、0和0.75 t时为例，其型线如图 6所示。

 图 7 叶梢间距随导管拱度的变化 Fig. 7 Variation of tip clearance with cambers of duct

4.1.1 不同拱度导管的流场比较

 图 8 f=-0.75 t、f=0和f=0.75 t时导管O-xy截面上流线和轴向速度分布 Fig. 8 Flow lines and axial velocity distribution on O-xy section as f=-0.75 t, f=0, and f=0.75t

 图 9 f=-0.75 t、f=0和f=0.75 t时导管内沿中轴线的轴向速度分布 Fig. 9 Axial velocity distribution along x-axis as f=0.75 t, f=0, and f=0.75 t

 拱度 入口速度/(m·s-1) 中部速度/(m·s-1) 出口速度/(m·s-1) -0.75 t 1.314 474 1.808 438 1.267 485 0 1.193 269 1.366 831 1.190 093 0.75 t 1.047 939 0.909 793 1.023 590

 图 10 f=-0.75 t、f=0和f=0.75 t时导管桨O-xy截面上流线和轴向速度分布 Fig. 10 Flow lines and axial velocity distribution on O-xy section with propeller as f=-0.75 t, f=0, and f=0.75 t
 图 11 导管翼形剖面拱度对螺旋桨水动力性能的影响 Fig. 11 Influences of cambers of duct's airfoil section onpropeller's hydrodynamic performance

4.1.2 导管桨受力分析

4.1.3 桨叶压力分布

 图 12 f=-0.75 t、f=0和f=0.75 t时桨叶的叶背、叶面压力分布 Fig. 12 Pressure distribution on propeller's back and face as f=-0.75 t, f=0 and f=0.75 t

4.1.4 导管压力分布

 图 13 f=-0.75 t、f=0和f=0.75 t时导管压力分布 Fig. 13 Pressure distribution on duct as f=-0.75 t, f=0, and f=0.75 t

4.1.5 导管内流场分析

 图 14 f=-0.75 t、f=0和f=0.75 t时导管桨x/R=0处轴向速度分布 Fig. 14 Axial velocity distribution of ducted propeller on x/R=0 section as f=-0.75 t, f=0, and f=0.75 t

4.2 改变导管翼形剖面攻角

 图 15 α=-8°、α=0°和α=8°时导管翼形剖面示意图 Fig. 15 Schematic diagram of duct's airfoil sections as α=-8°, α=0°, and α=8°

4.2.1 不同攻角导管的流场比较

 图 16 α=-8°和α=8°时导管O-xy截面上流线和轴向速度分布 Fig. 16 Flow lines and axial velocity distribution on O-xy section as α=-8° and α=8°

 图 17 α=-8°、α=0°和α=8°时导管内沿中轴线的轴向速度分布 Fig. 17 Axial velocity distribution along x-axis as α=-8°, α=0°, and α=8°

 攻角/(°) 入口速度/(m·s-1) 中部速度/(m·s-1) 出口速度/(m·s-1) -8 0.750 235 1.086 298 1.117 297 0 1.193 269 1.366 831 1.190 093 8 1.682 453 1.472 395 1.130 847

 图 18 α=-8°和α=8°时导管O-xy截面上流线和轴向速度分布 Fig. 18 Flow lines and axial velocity distribution on O-xy section as α=-8° and α=8°
 图 19 导管翼型剖面攻角对螺旋桨水动力性能的影响 Fig. 19 Influences of attack angles of duct's airfoil section on propeller's hydrodynamic performance

4.2.2 导管桨受力分析

4.2.3 桨叶压力分布

 图 20 α=-8°、α=8°时桨叶的叶背、叶面压力分布 Fig. 20 Pressure distribution on propeller's back and face as α=-8° and α=8°

4.2.4 导管压力分布

 图 21 α=-8°和α=8°时导管压力分布 Fig. 21 Pressure distribution on duct as α=-8° and α=8°

4.2.5 导管内流场分析

 图 22 攻角为-8°和8°时导管桨x/R=0处轴向速度分布 Fig. 22 Axial velocity distribution of ducted propeller onx/R=0 section as α=-8° and α=8°

5 结论

1) 采用改变导管翼形剖面拱度的方式得到的加速导管可以使螺旋桨的推力和转矩大大降低，适合于低载荷高速船舶，而减速导管会增加螺旋桨推力和转矩，适合拖轮等重载荷船舶。

2) 采用改变导管翼形剖面攻角的方式得到的加速、减速导管对螺旋桨推力和转矩的影响恰好与采用改变导管翼形剖面拱度方法相反。

 [1] 马乾初, 汤忠谷, 张绍清. 船舶附体节能的现状与前景[J]. 武汉造船, 1992 (5): 36–40. MA Q C, TANG Z G, ZHANG S Q. Present situation and prospect of energy-saving appendages[J]. Wuhan Shipbuilding, 1992 (5): 36–40. (in Chinese) [2] 王超, 黄胜, 常欣, 等. 螺旋桨毂帽鳍水动力性能数值分析[J]. 船海工程, 2009, 38 (6): 20–24. WANG C, HUANG S, CHANG X, et al. The prediction of hydrodynamic performance of propeller boss cap fins[J]. Ship & Ocean Engineering, 2009, 38 (6): 20–24. (in Chinese) [3] 马骋, 蔡昊鹏, 钱正芳, 等. 螺旋桨与毂帽鳍集成一体化优化设计方法研究[J]. 中国造船, 2014, 55 (3): 101–107. MA C, CAI H P, QIAN Z F, et al. Research on integrated optimal design method of propeller and PBCF (propeller boss cap fins)[J]. Shipbuilding of China, 2014, 55 (3): 101–107. (in Chinese) [4] 崔承根, 施能继. 叶梢带端板螺旋桨的性能研究[J]. 华中科技大学学报(自然科学版), 1991 (3): 117–120. CUI C G, SHI N J. An investigation on the performance of a screw with endplates at blade tips[J]. Journal of Huazhong University of Science and Technology (Natural Science Edition), 1991 (3): 117–120. (in Chinese) [5] 罗奕鑫, 崔承根. 叶梢带端板螺旋桨的设计方法[J]. 造船技术, 1997 (8): 18–22. LUO Y X, CUI C G. Design of a screw with endplates at blade tips[J]. Journal of Marine Technology, 1997 (8): 18–22. (in Chinese) [6] 沈海龙.船体与节能附体及螺旋桨的非定常干扰研究[D].哈尔滨:哈尔滨工程大学, 2009. SHEN H L.Research on the unsteady interaction between ship hull and energy-saving appendage and propeller[D].Harbin:Harbin Engineering University, 2009(in Chinese). [7] 刘奕谦, 谢小龙. VLCC前置导管结构设计与强度分析[J]. 中国造船, 2013, 54 (4): 109–119. LIU Y Q, XIE X L. Structure design and stress assessment of wake equalizing duct for VLCC[J]. Shipbuilding of China, 2013, 54 (4): 109–119. (in Chinese) [8] 黄少锋, 黄国富, 杨奕. 伴流补偿导管节能增效的CFD评估方法研究[J]. 中国造船, 2012, 53 (A01): 7–12. HUANG S F, HUANG G F, YANG Y. Numerical prediction for effectiveness of wake equalizing duct[J]. Shipbuilding of China, 2012, 53 (A01): 7–12. (in Chinese) [9] FEITEN W, BAUER R, LAWITZKY G.Robust obstacle avoidance in unknown and cramped environments[C]//1994 IEEE International Conference on Robotics and Automation.Piscataway, NJ:IEEE Press, 1994:2412-2417. [10] 叶元培, 周连第, 郑永敏. 导管螺旋桨空泡性能系列试验研究[J]. 中国造船, 1980 (4): 27–41. YE Y P, ZHOU L D, ZHENG Y M. Experimental investigations of the performance of ducted propeller series in cavitating conditions[J]. Shipbuilding of China, 1980 (4): 27–41. (in Chinese) [11] 叶元培, 沈贻德. 双体导管螺旋桨系列试验研究[J]. 中国造船, 1979 (2): 3–36. YE Y P, SHEN Y D. A systematic study on the performance characteristics of propeller series with slotted nozzles[J]. Shipbuilding of China, 1979 (2): 3–36. (in Chinese) [12] KHATIB M.Sensor-based motion control for mobile robots[D].Toulouse:LAAS-CNRS, 1996. [13] 韩宝玉, 熊鹰, 叶金铭. 面元法预估导管螺旋桨定常性能的一种简便方法[J]. 船海工程, 2007, 36 (3): 42–45. HAN B Y, XIONG Y, YE J M. A simple method to predict the steady performance of ducted propeller with surface panel method[J]. Ship & Ocean Engineering, 2007, 36 (3): 42–45. (in Chinese) [14] 刘小龙, 王国强. 导管螺旋桨定常性能预估的基于速度势的面元法[J]. 船舶力学, 2006, 10 (3): 26–35. LIU X L, WANG G Q. A potential based panel method for prediction of steady performance of ducted propeller[J]. Journal of Ship Mechanics, 2006, 10 (3): 26–35. (in Chinese) [15] 杨晨俊, 王国强. 导管螺旋桨定常性能理论计算[J]. 上海交通大学学报, 1997, 31 (11): 36–39. YANG C J, WANG G Q. Theoretical prediction of the steady performance of ducted propellers[J]. Journal of Shanghai Jiaotong University, 1997, 31 (11): 36–39. (in Chinese) [16] KAWAKITA C. A surface panel method for ducted propellers with new wake model based on velocity measurements[J]. Journal of the Society of Naval Architects of Japan, 1992 (172): 187–202. [17] KINNAS S, HSIN C Y, KEENAN D.A potential based panel method for the unsteady flow around open and ducted propellers[C]//18th ONR, 1990:21-38. [18] 解学参, 黄胜, 胡健, 等. 导管桨内部流场的数值计算[J]. 哈尔滨工程大学学报, 2009, 30 (1): 7–12. XIE X C, HUANG S, HU J, et al. Inner flow field calculations for ducted propellers[J]. Journal of Harbin Engineering University, 2009, 30 (1): 7–12. (in Chinese) [19] 胡健, 黄胜, 马骋, 等. 影响导管桨内部流场的几个因素[J]. 天津大学学报, 2009, 42 (4): 340–344. HU J, HUANG S, MA C, et al. Several influence factors for the inner flow field of ducted propeller[J]. Journal of Tianjin University, 2009, 42 (4): 340–344. (in Chinese) [20] SANCHEZ-CAJA A, RAUTAHEIMO P, SIIKONEN T.Simulation of incompressible viscous flow around a ducted propeller using a RANS equation solver[C]//Proceedings of the 23rd Symposium on Naval Hydrodynamics.Washington, D.C.:National Academy Press, 2000:527-539. [21] PARK W G, JUNG Y R, KIM C K. Numerical flow analysis of single-stage ducted marine propulsor[J]. Ocean Engineering, 2005, 32 (10): 1260–1277. DOI:10.1016/j.oceaneng.2004.10.022 [22] 崔立新.导管螺旋桨的水动力性能及噪声性能预报[D].哈尔滨:哈尔滨工程大学, 2013. CUI L X.Prediction of hydrodynamic performances and noise of ducted propeller[D].Harbin:Harbin Engineering University, 2013(in Chinese).

#### 文章信息

HU Jian, WANG Nan, HU Yang

Performance comparison of accelerating duct and decelerating duct

Journal of Beijing University of Aeronautics and Astronsutics, 2017, 43(2): 240-252
http://dx.doi.org/10.13700/j.bh.1001-5965.2016.0140