IMPROVEMENT SCHEME AND VERIFICATION OF HIGH-FREQUENCY HEATING UNIFORMITY OF WOOD
This study was based on the finite element method to construct a high-frequency heating temperature field simulation model. In the model, the bending length and angle of top plate were changed upwards. The heating uniformity of test material was then analyzed under different conditions (bending length and angle) to identify the best improvement scheme and carry out the experimental verification. The results showed that when the bending length and angle of top plate were 200mm and 45°, the heating uniformity was the best. Comparison of temperature distribution along the width direction of test material before and after improvement, it was concluded that the temperature distribution was more uniform after improvement. Comparison the temperature difference between the center of test material and its length, width and thickness direction measurement point before and after improvement, the temperature difference was reduced by 7.6℃, 1.7℃, 3.4℃, respectively, which effectively improved the heating uniformity. Comparison of the changes in the electromagnetic field distributions between plates before and after improvement revealed an increase in distribution uniformity from 0.631 to 0.811. This indicated that the electromagnetic field distribution after improvement was more uniform with ideal heating effect. Overall, the improvement in bending length and angle of top plate could change the distribution of electromagnetic fields between the plates and enhance temperature distribution uniformity of wood during high-frequency heating.
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