Measurements of Local Wall Heat Transfer Coefficient in Sharp 180 Degree Turns in Multipass Rib-roughened Channels

多程肋粗化通道180度急转弯局部壁传热系数的测量

• 批准号: 8910860
• 负责人: S. Lau
• 金额: $ 8.82万
• 依托单位: Texas A&M Research Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-08-15 至 1992-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8910860&HistoricalAwards=false
• 关键词: Measurements; Local; Wall; Heat; Transfer

The heat transfer characteristics of turbulent air flow in the sharp turns in multipass rib-roughened cooling channels in high temperature gas turbine airfoils are to be studied. The cooling channels will be modeled as a series of rectangular channels, with rib-roughened walls, connected with two 180 degree turns. The local heat transfer coefficient distribution in and near the turns will be determined with both the naphthalene sublimation mass transfer technique and conventional foil heaters-thermocouples method. Experimental results will be obtained for various channel aspect ratios, turn clearance gaps, curvatures of the turn corners, rib geometries, and flow Reynolds numbers typical of turbine engine applications. Corresponding flow visualization experiments with the oil-lampblack technique will supplement the forced convection experiments. Effective blade cooling prolongs the life of advanced gas turbines. The results of this research will contribute to the understanding of the heat transfer and flow characteristics of multipass rib-roughened channels, which is important in the design of turbine engines.

研究了管内湍流空气的换热特性 多通道肋粗糙化冷却通道中的急转弯， 研究高温燃气涡轮机翼型。 的 冷却通道将被建模为一系列矩形 通道，带有肋状粗糙壁，与两个180 度转弯。 局部换热系数 在转弯处和转弯附近的分布将由 萘升华传质技术和 传统的箔加热器-热电偶方法。 实验 将获得各种通道纵横比的结果， 转弯间隙、转弯拐角曲率、肋 几何形状和涡轮机的典型流动雷诺数 发动机应用 对应流场可视化 油油烟技术的实验将补充 强制对流实验 有效的叶片冷却延长先进燃气轮机的使用寿命 涡轮机. 这项研究的结果将有助于 了解传热和流动特性， 多通道肋粗糙化通道，这在 涡轮机发动机的设计。