## 4 Discussion
Based on Figure 6b, it can be seen that, depending on the direction of rotation, the cells will accumulate in stage I and quickly return to their normal radial position after leaving the loading plate. Therefore, an increase in compression rate will strengthen the stacking effect of the cells before they make contact with the loading plate, while stage III gradually weakens or even disappears. In Section 3.3.1, the phenomenon of the radial displacement of node A\({}_{\text{e}}\) increasing in a stepped pattern before A\({}_{\text{e}}\)-C was analyzed. This was due to the cell column \(\alpha\) under the compression of the loading plate; the compression behavior being transmitted clockwise and backward; A\({}_{\text{e}}\) in cell column I being subjected to the cell column \(\alpha\); the force transmitted from B\({}_{\text{e}}\); the obtuse angle between the direction and the radial direction of column I; and the radial component of the stress nodes toward the outside of the roller. In addition, the compression effect weakened every time the stress was transmitted to a row of cells. Therefore, as cell column I approached the loading plate and moved away from the axis, the degree of distance gradually increased until A\({}_{\text{e}}\) made contact with the loading plate. Figure 13b shows that, similar to node \(\rm A_{e}\), the \(\rm B_{e}\) node's equivalent stress change process can also be divided into three stages. As shown in Figure 12b, the \(\rm B_{e}\) node's equivalent stress division interval was between \(\rm A_{e}\)-C and \(\rm\beta\)-R since \(\rm B_{e}\) made contact with the loading plate after the \(\rm A_{e}\) node. Figure 13b shows the relationship between the compression rate and the amount of work performed by the equivalent stress at the \(\rm B_{e}\) node in stages I, II, and III, as well as the percentage of work performed in each stage to the total amount. Similar to the variation in equivalent stress at node \(\rm A_{e}\), within the experimental range of 10% to 15% compression rate, the total work performed by the equivalent stress at node \(\rm B_{e}\) increased as the compression rate increased. In stage I, there was a positive correlation between the work performed and the compression rate. In stage II, the amount of work performed was higher than 11%, with a compression rate of 10%, followed by a gradual increase in the work performed. The amount of work performed in stage III was slightly higher at an 11% compression rate than at 10%, and then the amount of work performed in stage III showed a downward trend. When different from the \(\rm A_{e}\) node, the proportion of work performed by the \(\rm B_{e}\) node in stage II at each compression rate was about 30%, and the percentage of work performed by the \(\rm B_{e}\) node in stage III was higher than that of the \(\rm A_{e}\) node. During the time the \(\rm B_{e}\) node was passing through the loading plate, the work performed in stages I and II increased as the compression rate increased. However, the work performed in stage I dominated. From Figure 7b, it can be seen that the \(\rm B_{e}\) node made contact with the loading plate near 175\({}^{\circ}\), which means that in stage I, the \(\rm B_{e}\) node was subjected to stress transmitted from the \(\rm A_{e}\) node through the \(\rm C_{e}\) node, while in stage II, it was limited by the loading plate and was mainly affected by the force applied by the loading plate. It can be seen that the effect of the \(\rm A_{e}\) node on the equivalent stress of the \(\rm B_{e}\) node was greater than that of the loading plate. As shown in Figure 5, the \(\rm A_{e}\) node exhibited displacement toward the outside of the roller before coming into contact with the loading plate, and the degree of outward displacement was affected by the compression rate. The difference between the maximum and minimum radial displacement of node \(\rm A_{e}\) within one revolution of the roller is called the maximum radial displacement amplitude, \(\Delta R\).