木材动态力学特性对热磨过程能耗的影响1）

以杨木为试材，应变率为400、700、1000 s－1，含水率为气干、全饱和，加载方向为弦向、径向、轴向；用分离式霍普金森杆（SHPB）试验装置测试了木材动态力学特性，分析了木材动态力学特性对热磨过程中能量消耗的影响。结果表明：①全饱和材比气干材更易解离。②在同一个应变率范围内，弦向抗压强度最小，轴向抗压强度最大；进料时，若能使大部分原料沿着弦向进料，而避免沿着轴向进料，则会减少研磨过程中的能量消耗。③当应变率在400～1000 s－1范围内变化时，轴向的抗压强度值随应变率的增加而增大，但增加幅度随应变率的增加而减小；弦向、径向的抗压强度随应变率的增加先增大而后减小。热磨过程中，增大磨盘转速提高纤维分离过程的应变率，可以减少热磨过程中的能量消耗。

Effect of Wood Dynamic Mecha nical Characteir stics on Thermal Energy Consumption in Reif ning Process

We tested the wood dynamic mechanical characteristics of sample with its strain rates of 400 s-1 , 700 s-1 , and 1 000 s-1 , and the loading directions of tangential , radial and axial , respectively , and analyzed the wooden dynamic mechanical characteristic’s impact on energy consumption during the refining process in the split Hopkinson pressure bar (SHPB) ex-periment.The fully saturated poplar is dissociated easily , compared with the air dry one .In the same stain rate range , tan-gential compression strength is the minimum and compression strength along axial is the maximum .Energy consumption will be reduced in the refining process if most materials are fed in tangential direction rather than axial .When strain rate ranges from 400 to 1 000 s-1 , axial compression strength will increase simultaneously , but increase slowly later , and both tangen-tial and radial compression strength will increase at first then decrease .In the refining process , increasing the speed of disks can increase the strain rate of fiber separation , and reduce the energy consumption in the refining process .