船闸输水系统多孔相向紊动射流流动结构及消能机理研究

Multiple face-to-face turbulent jets as an important flow regime are common in filling and emptying system of shiplocks. The flow structures of the jets are the internal influence factors on the mooring conditions of vessels passing shiplock. The flow mechanism of the jets is very complex for both the same flow characteristics as multiple jets and the complicated motion features generated from collision and shear response in submerged and geometry boundary conditions. Few researches on the flow structures, jet-jet and jets-water mixing and action characteristics, and energy dissipation mechanism are offered, presently. In this project, the following scientific issues will be researched seriously by establishing an experimental apparatus in steady flow conditions for multiple face-to-face turbulent jets, theoretical analyses, and numerical simulations. (1) Determing the key factors influencing flow structures and turbulence characteristics, obtaining the corresponding influence law. (2) Proposing quantitative mixture parameters and mechanical characteristics of vortex. Based on the above research results, the corresponding flow structures, mixture characteristics, action law, and energy dissipation mechanism will be achieved. Results of this research will further enrich the theory basis of the shiplock hydrodynamics and jet mechanics, and provide technical support for the construction and safety operation of shiplock engineering.

多孔相向紊动射流是船闸输水系统水动力学的常见流动问题，其流动结构是影响过闸船舶停泊安全的本质。多孔相向紊动射流不仅具有多孔射流特征，且需考虑淹没条件和几何边界条件下的相向碰撞、错流等流动特性，流动机理十分复杂。目前，对其流动结构、掺混特性和动力相互作用机制以及消能机理尚缺乏系统研究。本项目拟设计一座恒定多孔相向紊动射流试验系统，并结合理论分析和数学建模等研究手段，重点解决以下科学问题：（1）明确多孔相向紊动射流流动结构和紊动特性的关键控制因素及内在响应特征；（2）量化多孔相向紊动射流的掺混特征参数和涡动力学特性。预期阐明船闸输水系统多孔相向紊动射流的流动结构、射流间及与周围水体的掺混特性和动力相互作用机制，揭示多孔相向紊动射流消能机理。研究成果将丰富船闸水动力学和射流力学理论基础，为船闸工程的建设和安全运行提供科学依据。

多孔相向紊动射流是船闸输水系统水动力学的常见流动问题，其流动结构是影响过闸船舶停泊安全的本质。多孔相向紊动射流不仅具有多孔射流特征，且需考虑受限空间内的相向碰撞、错流等流动特性，流动特征十分复杂。目前，对其流动结构、掺混特性和动力相互作用机制以及消能机理尚缺乏系统研究。本项目主要采用PIV量测和数值模拟方法，围绕多孔相向紊动射流流动结构、掺混特性及作用机制、消能机理开展了研究。揭示了有限空间内单孔三维壁面射流时均流动结构，得到了淹没水深、射孔雷诺数对流动结构的影响规律；获得了不同孔间距、射流动量通量比条件下相向射流混合区内的主射内侧扩展规律和速度衰减规律；构建了相向射流混合区关键控制因子与主射流内侧扩展率和速度衰减、混合点距离、掺混高度的内在关系式；建立了不同射孔弗汝德数下的孔间距与相向孔间距、动量通量长度比尺、孔高以及掺混高度间的关系图谱，给出了孔间距的合理取值（s/lm=4-5）；分析了关键控制因子与时均涡结构的相互影响关系，阐明了相向射流间及与周围水体的掺混特征和相互作用机制；对比分析了单孔、串行双孔、相向双孔和三孔射流消能特征及消能效果，并揭示了多孔相向紊动射流消能机理。研究成果可丰富船闸水动力学和射流力学理论基础，为船闸工程的建设和安全运行提供科学依据。