水下平板通气减阻特性研究  

Drag reduction characteristics of an underwater air lubrication flat plate

作　　者：余恒安 张焕好[2] 陈志华[2] 郑纯[2] 彭江舟 YU Heng′an;ZHANG Huanhao;CHEN Zhihua;ZHENG Chun;PENG Jiangzhou(Beijing Power Machinery Research Institute,Beijing 100074,China;National Key Laboratory of Transient Physics,Nanjing University of Science and Technology,Nanjing 210094,China)

机构地区：[1]北京动力机械研究所,北京100074 [2]南京理工大学瞬态物理国家重点实验室,江苏南京210094

出　　处：《哈尔滨工程大学学报》2024年第6期1152-1161,共10页Journal of Harbin Engineering University

基　　金：瞬态物理重点实验室基金项目(614260403041802)。

摘　　要：为了研究通气射流对水下平板阻力特性的影响,本文采用Mixture多相流模型和Realizable k-ε湍流模型研究了三维水下平板通气射流的流动结构特征,得到了水下平板表面气液流场结构和减阻特性。数值结果表明:气体注入后,受来流影响而紧贴壁面向下游发展。当气体稳定覆盖在平板壁面后,平板阻力系数较不通气情况降低了16.73%。另外,因气体注入壁面边界层后,提升了壁面上的速度梯度,降低了壁面流体粘性系数;在气膜覆盖区(α_(l)>80%),因流体粘性系数的下降量远大于速度梯度的上升量,使流体粘性系数对气膜核心区内的减阻率起决定性作用;对于远离气膜核心区外的壁面,切向速度梯度对摩擦阻力系数的贡献增强。To study the effect of ventilation jets on the resistance characteristics of underwater flat plates,the mixture multiphase flow model and Realizable k-ε turbulence model investigated the flow feather of a three-dimensional underwater flat vented jet,obtaining the structure and drag reduction characteristics of the gas-liquid flow field on the underwater flat surface.Numerical results showed that after the gas was injected,it was affected by the incoming flow and developed downstream closely along the wall.When the gas stably covered the plate wall,the resistance coefficient of the plate was 16.73% lower than the unventilated case.Because of the injection of gas on the wall boundary layer,the wall velocity gradient was increased,and the wall fluid viscosity coefficient was reduced;in the gas film coverage area(α_l>80%),because the decrease in the fluid viscosity coefficient was much greater than the increase in the velocity gradient,the fluid viscosity coefficient played a decisive role in the drag reduction rate in the core region of the gas film;for the wall far from the core area of the gas film,the contribution of the tangential velocity gradient to the friction resistance coefficient was enhanced.

关 键 词：通气射流 平板 减阻率 粘性系数 速度梯度 核心区 数值模拟 摩擦系数 

分 类 号：TK79[动力工程及工程热物理—流体机械及工程]