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Numerical simulation was conducted to study the thermal history of Czochralski growth of large silicon single crystals. The computations were performed for various crystal diameters and emissivities of the crucible inner wall. The analysis gives the change of temperature distribution in the crystal and the shape of the solid-melt interface. The computed results show the importance of the effects of radiation from the crucible inner wall and the melt free surface on crystal growth. Also, increasing crystal diameter decreases the pull speed and increases the concavity of the solid-melt interface into the crystal. The result of this analysis is in good agreement with measurement of the pull rate on production apparatus, and the shape of the crystal-melt interface showed a tendency to qualitatively agree with the observations of X-ray diffraction.

The heat transfer performance of coaxial straight heat pipes in high-speed rotation has been analyzed. The parameters are the geometry of the pipe, the kind of working fluid, the mass of the working fluid charged in the pipe, the rotation rate and the heat load. As a result of the analysis, the distribution of film thickness in the pipe, the Nusselt number of the evaporator and condenser section, and the dryout conditions at the end of the evaporator section were found. The Nusselt number from the present analysis is compared with the experiment by Ohtsuka et al. The predictions are is good agreement with the experimental data in the condenser section, but are about 80 100% lower in the evaporator section.