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Modified Laser Flash Method for Thermal Properties Measurements and the Influence of Heat ConvectionThe study examined the effect of natural convection in applying the modified laser flash method to measure thermal properties of semiconductor melts. Common laser flash method uses a laser pulse to heat one side of a thin circular sample and measures the temperature response of the other side. Thermal diffusivity can be calculations based on a heat conduction analysis. For semiconductor melt, the sample is contained in a specially designed quartz cell with optical windows on both sides. When laser heats the vertical melt surface, the resulting natural convection can introduce errors in calculation based on heat conduction model alone. The effect of natural convection was studied by CFD simulations with experimental verification by temperature measurement. The CFD results indicated that natural convection would decrease the time needed for the rear side to reach its peak temperature, and also decrease the peak temperature slightly in our experimental configuration. Using the experimental data, the calculation using only heat conduction model resulted in a thermal diffusivity value is about 7.7% lower than that from the model with natural convection. Specific heat capacity was about the same, and the difference is within 1.6%, regardless of heat transfer models.
Document ID
20040000604
Document Type
Conference Paper
Authors
Lin, Bochuan (Alabama Univ. Birmingham, AL, United States)
Zhu, Shen (NASA Marshall Space Flight Center Huntsville, AL, United States)
Ban, Heng (Alabama Univ. Birmingham, AL, United States)
Li, Chao (Alabama Univ. Birmingham, AL, United States)
Scripa, Rosalia N. (Alabama Univ. Birmingham, AL, United States)
Su, Ching-Hua (NASA Marshall Space Flight Center Huntsville, AL, United States)
Lehoczky, Sandor L. (NASA Marshall Space Flight Center Huntsville, AL, United States)
Date Acquired
August 21, 2013
Publication Date
January 1, 2003
Subject Category
Fluid Mechanics and Thermodynamics
Meeting Information
Proceedings of IMECE2003: 2003 ASME International Mechanical Engineering Congress and R&D EXPO(Washington, DC)
Funding Number(s)
CONTRACT_GRANT: NAS8-02096
Distribution Limits
Public
Copyright
Other