Abstract:
In order to reveal the stress relaxation law of cut tobacco after compression and to obtain the relevant rheological parameters of compressed cut tobacco, the creep-stress relaxation behavior of cut tobacco was tested using a cut tobacco rheological tester. A mathematical model characterizing the stress relaxation process of the stacked cut tobacco was established. The stress relaxation behavior of cut tobacco compressed under different conditions was analyzed, and the rheological parameters of cut tobacco during compression were solved. The results showed that: 1) The stacked tobacco had good compression viscoelastic mechanical properties, the relaxation rate was the fastest within the first 5 s during stress relaxation, and the stress decay rate slowed down after the relaxation process lasted for about 60 s, and there was equilibrium stress in the last stage. 2) The rheological characteristics of stacked cut tobacco during compression could be described by the five-element generalized Maxwell model with a correlation coefficient
R2 greater than 0.994. 3) The effects of sample amount and compression loading on the stress relaxation behavior of cut tobacco were investigated, and the rheological properties obtained were analyzed. It was found that the equilibrium stress increased with the increase of sample quantity and compression load. The stress relaxation time ratio
α was negatively correlated with the sample amount and positively correlated with the compression load. The expression of this law provides a method to study the relationship between the stress relaxation properties of cut tobacco and the macroscopic quality of tobacco under different storage and high-speed manufacturing conditions.