加热对自然转捩湍斑产生影响的实验研究  

AN EXPERIMENTAL INVESTIGATION OF EFFECT OF HEATING ON THE BURSTING OF NATURAL TRANSITIONAL TURBULENT SPOTS

作　　者：杨立[1] 蒋小勤[1] 周福国[1] 杜先之[1] 

机构地区：[1]海军工程学院热工教研室,武汉430033

出　　处：《工程热物理学报》1997年第4期474-478,共5页Journal of Engineering Thermophysics

基　　金：国家自然科学基金

摘　　要：本文利用流动显示和高速摄像技术，在湍流度为1％的水洞中，对加热的细长旅成体鱼雷模型表面的流动转捩过程进行了实验研究。实验发现，加热对自然转捩过程中湍流斑的猝发有明显影响，加热减小了湍斑产生的频率，增加了湍斑间的展向间距，使转捩过程中层流转变为完全湍流的过渡区延长．加热对瑞斑产生的纵向位置无明显影响。本文的实验结果正好解释在较高湍流庭环境中的加热减阻机理．In this paper, the transitional process of fluid flow from laminar to turbulence on the surface of a torpedo model by heating are studied experimentally in the water tunnel with the high speed shutter camera and the means of flow visulization. It is found that the surface heating has a significant effect on the bursting of turbulent spots in the natural transitional process. Surface heating can decrease the bursting frequency of turbulent spots and increase the distance between the two turbulent spots. It has no evident effect on the longitudinal regions of the bursting of spots in this conditions of experiments. The transitional regions from laminar to turbulence on the surface of model by heating become longer than that by no heating. The experimental results of this paper can explain the mechanism of drag reduction of underwater vehicle by heating.

关 键 词：湍流 加热 鱼雷 流动转捩 湍斑 

分 类 号：O357.53[理学—流体力学] U674.750.1[理学—力学]