Summary: | 碩士 === 淡江大學 === 機械工程學系 === 89 === The major work of this thesis is to study the temperature distribution in the furnace. Its purpose is to investigate the influence of the temperature field due to the various heating sources for an inclined furnace. The content is divided into two parts:experimentation and numerical analysis. For experimentation, the sesame thermal conductivity and thermal diffusivity are measured. Then use the least-square method to deduce the thermal conductivity relate to the temperature and the moisture rate. When temperature range from 20℃~40℃ and moisture rate range from 2.3﹪~6﹪, the results are:
K = 0.00204 T + 0.095……(moisture rate is 2.3%)
K = 0.00342 T + 0.0744……(moisture rate is 4%)
K = 0.00224 T + 0.1322……(moisture rate is 6%)
where K:thermal conductivity, W/m-℃
T:temperature, ℃
When temperature is 30℃, the thermal diffusivity relate to the moisture rate is:
α= 0.0053 M + 0.087
where α:thermal diffusivity
M:moisture rate, %
For numerical analysis, the temperature field originating from the different heating sources for the furnace is analyzed by using the finite element analysis software-ANSYS. According to the result of analysis, the temperature distribution in furnace is better while the discrepancy between the heat flux is smaller. Heating area causes the most influence of the temperature in furnace. When the region near the outlet is subjected to higher heat flux, the sesame is easily burned. When the region in the middle of the furnace is subjected to higher heat flux, we have a higher average temperature. According to the empirical viewpoint, the optimum temperature distribution is that the temperature in the furnace should be the highest in the middle and decreases on both two sides. It is found, when furnace is subjected to a sine function heat flux, the temperature field in the furnace will be the best choice.
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