New Paradigms for Inverse Heat Conduction Problems: Creative analytics and experiments utilizing advanced technologies

该项目允许对由于恶劣的热环境而高度难以捉摸和难以解决的问题进行系统调查。这些条件出现在高速飞行、燃烧、材料加工、飞机和自动刹车、化学和能源过程、火灾研究、地球物理科学以及国防和国家安全应用中。这些应用为解释感兴趣的工程量所需的地面仪器提供了困难的情况。因此，诺克斯维尔田纳西大学正在开发的方法允许执行深入或背面分析，呈现由恶劣环境造成的表面温度和热通量。建议的方法既具有变革性，又自然地对工程的其他领域产生更广泛的影响，因为它代表了一种新的范式。将进行计算和实验研究，以表明该方法和新设计的小型样品测试设施的优点。此外，研究成果将被纳入本科生和研究生课程，以加强创造性地解决问题。将开发一个短期课程和研讨会，供大学、会议和有兴趣的行业使用，以确保具有国际竞争力。该项目提供了变革性的分析概念和新的实验发展，用于解决适用于经典(需要参数)和校准(无参数)公式的逆热传导问题。在标定测试设备的基础上，设计了基于元器件验证的实验。随着应用变得极端，逆向分析受到了极大的关注，从而造成了仪器噩梦。高温和高热流密度的应用会严重损害地面仪器，使其对未来的解释毫无用处或不可靠。当可靠的表面评估对于了解实际情况至关重要时，就会出现这种情况。该项目促进了需要实验验证的线性和非线性研究的新配方的开发。实验验证的基础是开发一种小样本、开放式结构的测试设备，允许使用最新的仪器和加热源在空气、惰性气体和轻真空条件下进行测试。将设计、制造和测试适用于航空航天和机械工程界的基准质量测试设施。新型高温、高热流密度电加热器是最基本的加热元件。这些加热器由氮化铝和钨痕迹组成，与RTD？S完全集成在一个薄封装中。可以开始仔细的成分研究，以准确地量化设计构型中的热通量。在系统校准过程中，薄膜热电偶将粘在试件上以估计表面温度。前沿条件，即表面温度和热流，将替代地使用脉冲回波超声换能器测量往返时间。传统的逆热传导是以深度仪器的可用性为前提的，并要求指定热物理和几何特性；以及传感器特性。量化热物性和传感器特性是昂贵的，并且需要大量的时间努力。从理解校准视图中获得的洞察力可以用于改进经典的逆方法。在内部，如果测试设施可以为交钥匙结果而设计，校准可以减少成本和时间延迟。将声学仪器集成到校准方法中是新颖的，将导致基于对侧测量的准确的表面温度和净热流预测。

This project allows for the systematic investigation of problems that are highly elusive and difficult to solve owing to harsh thermal environments. These conditions appear in high-speed flight, combustion, material processing, airplane and automatic brakes, chemical and energy processes, fire research, geophysical sciences, and defense and national security applications. These applications render a difficult situation for surface instrumentation needed for interpreting engineering quantities of interest. As such, the methods under development at the University of Tennessee, Knoxville allow for in-depth or backside analyzes to be performed rendering the surface temperature and heat flux caused by the harsh environment. The proposed approach is both transformative and possesses a natural broader impact to other areas of engineering as it represents a new paradigm. Both computational and experimental studies will be performed indicating the merit of the methodology and a newly designed small sample test facility. Further, the research findings will be incorporated into undergraduate and graduate courses for enhancing creative problem solving. A short-course and workshop will be developed for presentation at universities; conferences; and, available to interested industries for assuring an international competitive edge.This project offers transformative analytical concepts and novel experimental developments for resolving inverse heat conduction problems applicable to both classical (parameters required) and calibration (parameter free) formulations. Experiments are designed based on component validation in the edifice of calibration test facility. Inverse analysis is receiving significant attention as applications are becoming extreme and thus creating instrumentation nightmares. High temperature and high heat flux applications can significantly damage surface instrumentation rendering it either useless or unreliable for future interpretation. Such situations arise where reliable surface assessments are fundamental to understanding the physical situation. This project promotes the development of new formulations for both linear and nonlinear studies that require experimental verification. Experimental verification is based on developing a small sample, open architecture test facility that allows for air, inert gas and light vacuum conditions using the latest instrumentation and heating sources. A benchmark quality test facility will be designed, fabricated and tested applicable to the aerospace and mechanical engineering communities. New high temperature and high heat flux electrical heaters represent the fundamental heating element. These heaters are composed of aluminum nitride with tungsten traces that are fully integrated with RTD?s in a thin package. Careful component studies can be initiated to accurately quantify the heat flux in a designed configuration. Thin film thermocouples will be adhered to the test specimen for estimating the surface temperature during the system calibration. The front condition, i.e., surface temperature and heat flux, will alternatively be estimated using a pulse-echo ultrasonic transducer for measuring round-trip time. Conventional inverse heat conduction is predicated on the availability of in-depth instrumentation and requires the specification of thermophysical and geometrical properties; and, sensor characteristics. Quantification of thermophysical properties and sensor characteristics is costly and requires a significant time effort. Insight gained from understanding a calibration view can be applied for improving classical inverse methods. In-house, calibration reduces costs and time delays if a test facility can be designed for turn-key results. Integrating acoustic instrumentation into the calibration approach is novel and will lead to accurate surface temperature and net heat flux predictions based on an opposing-side measurement.