Research Initiation: Heat Transfer and Fluid Flow in FusionWelding

研究启动：熔焊中的传热和流体流动

• 批准号: 8808970
• 负责人: Yogendra Joshi
• 金额: $ 7万
• 依托单位: Naval Postgraduate School
• 依托单位国家: 美国
• 项目类别: Interagency Agreement
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-06-01 至 1991-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8808970&HistoricalAwards=false
• 关键词: Research; Initiation; Heat; Transfer; Fluid

This research is an experimental and computational investigation of the thermo-fluid processes associated with fusion welding. The effort is divided into three smaller, clearly focused investigations. The first of these is an experimental simulation of fusion welding, employing a low melting point eutectic. Detailed temperature measurements and surface fluid flow visualizations will be carried out to study the multidimensional, transient transport processes involving phase change. This study will provide a starting point for the subsequent temperature measurements in the gas tungsten arc (GTA) welding process. Thermal histories at various locations during GTA welding will be measured for lead, aluminum and steels. To complement the two experimental studies, computations of heat transfer and fluid flow during fusion welding will also be performed. There are two primary goals of this research. First, a fundamental understanding of the heat transfer and fluid flow processes associated with fusion welding is sought. A number of complex features such as multidimensional convection and conduction transport, change of phase, surface tension and multiple of physical mechanisms which have not previously been considered together in detail. These studies will also provide guidelines to the welding engineer to correlate the thermo-fluid processes with the post weld mechanical properties. In addition, the possibility of providing real time corrective action during welding, using heat and fluid flow measurements will be examined. This will permit real time control of automated welding operations to improve weld quality.

这项研究是一个实验和计算调查， 与熔焊相关的热流体过程。 的努力 分为三个较小的，明确的重点调查。 的 首先是熔焊的实验模拟， 采用低熔点共晶。 详细温度 将进行测量和表面流体流动可视化 研究多维度的、瞬时的运输过程， 相变 本研究将为以下方面提供一个起点： 气体钨极电弧（GTA）中的后续温度测量 焊接工艺 GTA期间不同位置的热历史 将测量铅、铝和钢的焊接。 以补充 两个实验研究，传热和流体计算 还将进行熔焊期间的流动。 这项研究有两个主要目标。 首先，一个基本的 了解相关的传热和流体流动过程 寻求熔焊。 一些复杂的特征，如 多维对流和传导传输，相变， 表面张力和多种物理机制， 以前被详细地考虑过。 这些研究将 还为焊接工程师提供指导， 热流体工艺与焊后机械性能。 在 此外，提供真实的时间校正动作的可能性 在焊接过程中，使用热量和流体流量测量将是 考察 这将允许自动焊接的真实的时间控制 提高焊接质量。