【作者】 沈海龙；

【导师】 苏玉民；

【作者基本信息】 哈尔滨工程大学 ， 工程力学， 2009， 博士

【摘要】 船舶节能已成为世界各国造船界和航运界研究的重要课题,它关系到节省燃料、减少运输成本、环境保护以及提高企业的经济效益等问题。船舶推进附加节能装置是实现船舶节能的有效措施之一,具有节能效果显著、结构简单和造价低廉的特点。用数值方法对其展开研究,从流场流动细节上分析它对船体伴流场的影响,具有重要的理论意义和工程价值。本文以探寻桨前节能装置的数值研究方法为目的,基于面元法理论和CFD技术研究了船体与节能附体及螺旋桨之间的非定常干扰。首先,论文基于滑移网格技术研究了粘性流场中螺旋桨的水动力性能预报方法,使用CFD前处理软件划分流场网格,生成多块混合网格,讨论了基于滑移网格技术的流场网格处理方法、三维螺旋桨几何建模方法、壁面Y+值和计算稳定性的判断方法等影响计算精度的关键因素,分析了不同湍流模式对预报结果的影响,预报了均匀伴流场中DTRC4842和PHS螺旋桨的非定常水动力性能和非均匀伴流场中Seiun-Maru HSP螺旋桨的非定常水动力性能。其次,为寻求适合肥大型船伴流场的数值预报方法,讨论了船体几何模型的建模方法,详细比较和分析了流场网格划分方法对计算结果的影响,研究了不同湍流模式预报肥大型船粘性伴流场的适用性。通过数值结果与试验结果的比较,得到了适合肥大型船伴流场数值预报的网格划分方法和湍流模式。为验证该网格划分方法和湍流模式的适用性,预报了某化学品运输船和某集装箱船的桨盘面伴流场。然后,采用与螺旋桨水动力性能预报和船体伴流场预报同样的流场处理方法和网格划分方法,应用GAMBIT、Tgrid和ICEM CFD三种网格划分软件共同完成流场网格的划分,使用Detached Eddy Simulation(DES)湍流模型,研究了船体、螺旋桨、船桨组合这三种模型的水动力性能,分析了船桨相互干扰对船体和螺旋桨的影响。最后,论文在准确预报某肥大型船伴流场的基础上,参考流体轨迹绕船体分布的特点,分别设计了螺旋桨前置导管、补偿导管和整流鳍,预报并分析了各附体对船体伴流场的影响,给出了决定节能效果的伴流场特征,从流场流动细节分析了节能附体的工作机理。结合该船裸船体伴流分布的试验值和安装三种节能附体后船体伴流分布的计算值,基于面元法理论和CFD技术预报了这三种节能装置的节能效果,得到了一种基于面元法理论和CFD技术的桨前节能装置设计及其节能效果预报的数值研究方法。更多还原

【Abstract】 The energy saving of ships has become an important task in shipbuilding and shipping field of the world. It relates to the fuel saving, the cost reduction of transportation, environment protection and profit increase of the enterprise. Installing the energy saving appendages in ships is an effective method for the energy saving, which have characteristics of significant energy saving effect, simple structure and low cost. The energy saving device was studied by a numerical method and the influence of the energy saving device on ship wake was analyzed from the point of flow field details, which had an important theory meaning and engineering value. Based on surface panel method and CFD technique, the unsteady interaction between hull, energy saving appendages and propeller was studied in the paper. The purpose of the paper was to obtain a numerical analyzing method of hydrodynamic performances of energy saving devices.Firstly, this paper studied the prediction method of the propeller performance in viscous flow field, which was based on sliding mesh technique. And the paper used the CFD pre-processor to partition the flow filed mesh and generate multi-block hybrid mesh. Key factors that influenced the precision of calculation were analyzed which included the disposal method of flow field mesh based on the sliding mesh technique, the modeling method of three dimensional propeller geometry model, the wall Y+ value and the judgmental method of calculation stability. The influences of different turbulence models on prediction results were analyzed. The unsteady hydrodynamic performance of DTRC4842 and PHS propeller in uniform wake was predicted. And the unsteady hydrodynamic performance of Seiun-Maru HSP propeller in non-uniform wake was also predicted. Secondly, in order to get the suitable numerical prediction method of flow field of the full form ship, the modeling method of ship geometry model was discussed in the paper. And the influences of mesh partition methods on calculation results were compared and analyzed in details. The applicability of different turbulence models which were used to predict the viscous flow field of full form ship was studied. The mesh partition methods and turbulence models were obtained by comparing the numerical results and experimental results. The wake fractions on the propeller disc of a certain chemical tanker and a container vessel were simulated to validate the applicability of the mesh partition methods and turbulence models.Thirdly, the paper studied the hydrodynamic performance of three cases, which included ship without propeller, propeller without ship and ship with propeller. The paper analyzed the influence on the ship hull and propeller caused by the unsteady interaction between ship and propeller. The flow field disposal methods and mesh partition methods were the same as methods of predicting the propeller performance and the flow field of full form ship. This paper used GAMBIT, Tgrid and ICEM CFD to partition the flow filed mesh. The Detached Eddy Simulation turbulence model was chosen in the study.Finally, based on the prediction of the wake of one full form ship, the pre-position duct of propeller, compensating duct and diversion fin were designed which based on the water tracks distribution characteristic through ship hull. And the influences of the appendages on the wake were predicted and analyzed. The characteristics of flow field were found which decided the energy saving effect. The working mechanism of energy saving appendages was analyzed from the flow field details. Combined with the experimental wake of the naked hull and calculation wake of hulls with three type energy saving devices, the energy saving effect of the three types energy saving devices was predicted using surface panel method theory and CFD technique. A numerical study method of pre-propeller energy saving devices was obtained which could be used to design energy saving devices and predict the energy saving effect based on surface panel method theory and CFD technique.更多还原