Adaptive Double-Diffusion Model and Comparison to a Highly Heterogeneous Micro-Model

Table 8

Cost of one-grid versus two-grid discretization in a simulation with 1,000 time steps.

One-grid with ℎ1=ℎ2=1/80
Matrix	Cost (seconds)
𝑆1,ℎ1 + 𝑀1,ℎ1	3.6547
𝐵one-grid	0.0123
Solve 𝕊one-grid 1,000 times	0.2761 × 1,000
Total	279.7670
Two-grid with ℎ1=1/80,ℎ2=1/20
Matrix	Cost (seconds)
𝑆1,ℎ1 + 𝑀1,ℎ1	3.6547
𝑀2,ℎ2	0.0438
𝕀ℎ1,ℎ2	0.2121
𝐵two-grid	0.0063
Solve 𝕊two-grid 1,000 times	0.1030 × 1,000
Total	106.9169