Analysis on Heat Transfer Characteristics of Thin Metallic Films Subjected to Nonequilibrium Pulse Laser Heating

• Main Authors: Yi-Chang Huang, 黃怡彰
• Other Authors: Jenn-Der Lin
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/90838842155663517472

碩士 === 國立交通大學 === 機械工程系 === 89 === This thesis investigates the effect of the electron thermal conductivity on electron temperature in the microtime scale. Besides, an inverse analysis is performed for simultaneous estimation of both thermal conductivity and the electron-phonon coupling factor of thin metal films during nonequilibrium laser heating of metals. Consequently, the influence of the relation between the electron thermal conductivity to electron temperature on the two-step model is not so significant during short-pulse laser heating. Theoretical analyses on the sensitivity coefficients illustrate that optimal choices of measurements would include temperature variations at the front surface over the time interval after the electron temperature reaches its maximum, combined with measurements of temperature variations at the rear surface for the whole thermalization time. Furthermore, we discuss whether we could regard the linear variation of the reflectivity as changed with the electron temperature when the laser pulse duration is too short to measure the variation of electron temperature directly. Results show that the linear relationship of the reflectivity and electron temperature leaves us a matter for future consideration.