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AN ANALYSIS OF HEATING UNIFORMITY IN WOOD HIGH-FREQUENCY DRYING

Hao-jie Chai, Jing-Yao Zhao, Ying-Chun Cai

Abstract


The high-frequency heating temperature field simulation model was built using finite element method and validated by experiments. Under the premise of ensuring model accuracy, the model parameters (plate spacing and area, wood dielectric constant, stack length and width, and heating time) were individually varied to assess the impact of these parameters on wood heating uniformity. The results showed the following: 1) The model has good accuracy as verified by experiments. 2) In the thickness direction, the middle layer temperature was higher than the upper and lower surface temperatures; in the length and width directions, the center temperature was lower than those of both ends and both sides, and the temperature at the corners was the highest. 3) The smaller the distance between the plates, the better the heating uniformity; with the plate area increasing, the heating uniformity first increased and then decreased; the smaller the wood dielectric constant, the better the heating uniformity; as the continuous heating time increased, the heating uniformity first decreased, then increased, and then again decreased; as the length and width of the stack increased, the heating uniformity decreased first, then increased, and then again decreased; when they were the same size as the plate, the heating uniformity was the best.

 

 

 


Keywords


High frequency heating, wood drying, temperature field simulation model, heating uniformity

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