ELECTRIC RESISTANCE, MOISTURE CONTENT, WOOD TEMPERATURE RELATIONSHIPS OF Pinus elliotti Engelm BOARDS AT SIX DRYING TEMPERATURES: PRELIMIN ARY RESULTS
DOI:
https://doi.org/10.5902/19805098317Keywords:
Kiln drying, wood moisture content, wood temperature, electrical resistance, kiln control, Pinus elliotti.Abstract
Pinus elliotti Engels boards of 2,5x 13,0, 0x 50,0cm, were dried in a laboratory thermostatically controlled oven without air circulation, using temperatures of 50, 60, 70, 80, 90 and 100ºC. The objective was to measure and to correlate electric resistance, wood temperature and moisture constent. A data acquisition system was utilized measure and control the oven temperature and wood temperature during drying. The gravimetric method was employed to calculate the actual average wood moisture content. The analysis showed a good correlation beween wood temperature and wood moisture content, low correlation between electric resistance and wood moisture content, in the range of around 7% to 110%. The inclusion of wood temperature variable in the models gives excellent regression equations, indicating the importance of this variable in the wood moiture content estimates. Tables with regression analysis, data and multiple regression models to the six studied temperatures are presented.
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