EAGER: Experimental Verification of a Transformative Calibration Method

University Of Tennessee Knoxville, Knoxville TN

Investigators

Abstract

1137625 Frankel A novel calibration method is under development that produces accurate surface heat flux predictions in highly hostile thermal environments without requiring surface instrumentation. This concept has substantive merit for investigating: a) the effectiveness of thermal protection systems associated hypersonic flight vehicles or for understanding thermal efficiencies in hypersonic combustors; b) heat transfer on unreachable surface structures such as found in combustion liners, small chambers, and containment walls as a result of a hostile thermal event; and, c) heat transfer on structures emanating from pool fires or explosions. A comprehensive method is proposed that integrates physical, experimental, mathematical and computational principles. The resulting formulation implicitly possesses full-sensor characterization, probe positioning, host material thermophysical properties, diffusion physics, and mathematical constants required for stable and accurate surface heat flux predictions. A second novel feature of the approach lies in the acquisition of the stabilizing parameters though multiple calibration experiments. The proposed methodology is applicable to one-, two-, and three-dimensional geometries involving either isotropic or orthotropic materials in one or multi-region configurations. Laboratory calibration will be performed using a fiber-optic, diode laser system. The new calibration method leads to a Volterra integral equation of the first kind; and, thus the coupon or specimen can be interpreted as a transducer ready for practical implementation. Intellectual Merit: The multipronged strategy weaves analysis, computations, sensor development, instrumentation and experimental methods throughout the complete solution process and addresses critical US applications in a responsive, aggressive and timely manner. New material development is expected to continue at an impressive rate. Responsive state-of-the-art accurate methods for estimating surface heat flux and temperature that includes sensor characterization still requires resolution for many application involving highly hostile environments. It should be noted that the novel calibration view to inverse heat conduction could impact other areas involving inverse estimation. Broader Impact: Success of the proposed research will impact aerospace, energy, fire, combustion, geophysical, defense and national security research and developments The multifaceted nature of the study enhances the research experience of our undergraduate and graduate students by providing an integrated view to problem solving. The research findings will be incorporated into undergraduate and graduate courses. Short course development will be pursued for presentation at universities; conferences; and, national laboratories. We propose an aggressive outreach plan for motivating HS students to strongly consider engineering as a career through a first-hand, and highly exciting laboratory experience.