RelIncreDisp

Relative Displacement Increment

In the governing equation,

$$\mathbf{K}\mathbf{\Delta }\mathbf{U}\mathbf{=}\mathbf{R},$$

this converger tests the following ratio,

$$\left|{\displaystyle \frac{\mathbf{\Delta }{\mathbf{U}}^{\mathbf{k}}}{\sum _{\mathbf{i}\mathbf{=}\mathbf{0}}^{\mathbf{k}}\mathbf{\Delta }{\mathbf{U}}^{\mathbf{i}}}}\right|⩽tol.$$

where $\mathbf{\Delta }{\mathbf{U}}^{\mathbf{k}}$ denotes the displacement increment of the $k$-th iteration.