对不同浓度、温度、打浆度、剪切速率对低浓杉木间伐材机械浆流变特性的影响进行了实验研究,并对不同因素引起浆料表观粘度变化的机理进行了分析.结果表明:浆料浓度、打浆度、温度及剪切速率都会对浆料的表观粘度产生影响.随着浆料浓度的增加,浆料表观粘度呈指数式增加;随温度的升高,浆料表观粘度则缓慢下降;打浆度影响浆料的微观结构,随着打浆度的升高,纸浆的表观粘度呈下降趋势;低浓纸浆的表观粘度则随剪切速率提高而递减.在实验测量范围内,杉木间伐材低浓纸浆为满足幂律关系的非牛顿流体,拟合的本构方程的流变特性指数n《1,因此其在测量范围内为假塑性流体.低浓纸浆流变特性的研究纸浆模塑生产线流送系统设计提供了依据.
The rheological behavior of low consistency thermomechanical pulp of Chinese fir harvested by intermediate thinning was analyzed. The results show that the apparent viscosity of pulp changed along with the beating degree, pulp consistency and shearing velocity. With the increasing of pulp consistency, the apparent viscosity of pulp increased gradually. Beating degree of pulp had an effect on microstructure of pulp. The apparent viscosity of pulp declined as beating degree of pulp increased, and the apparent viscosity of pulp fell along with the shearing velocity increasing. Based on the results, the rheological models are set up. The models showed that the fluid types of the low consistency pulp could be described as pseudoplastics fluids (non-Newtonian fluids).