# A Comparative Analysis of 3D Software for Modeling Fatigue Crack Growth: A Review
## 2 Software
### Numerical-Based Approaches
#### 2.1.7. ANSYS Workbench  
ANSYS Workbench is a comprehensive simulation platform widely used for modeling fatigue crack growth. It offers advanced tools and capabilities for accurately analyzing and predicting crack propagation behavior under cyclic loading conditions. By integrating fracture mechanics principles, material properties, and fatigue analysis techniques, ANSYS Workbench enables engineers and researchers to gain valuable insights into the fatigue life and durability of structures. ANSYS Workbench provides a range of crack growth models, including virtual crack closure technique (VCCT), extended finite element method (XFEM), and cohesive zone modeling (CZM). These models allow for accurate representation of crack geometry, consideration of complex loading conditions, and simulation of crack propagation in various materials and structures. SMART simulation is a cutting-edge innovation from ANSYS that addresses the critical challenge of crack initiation, growth, and fracture in product design. When designing components and structures, understanding their safety, reliability, and longevity is paramount. Traditionally, engineers relied on prototyping and physical testing for fracture analysis. However, ANSYS provides high-quality simulation software that allows engineers to predict toughness more efficiently than ever before. One key advancement is the Unstructured Mesh Method (UMM) in ANSYS Mechanical, which significantly reduces pre-processing time. By automatically generating an all-tetrahedral (tet) mesh for crack fronts, engineers achieve high-fidelity results while slashing meshing time from days to minutes [91; 92; 93; 94; 95; 96; 97; 98; 99; 100; 101]. The SMART Crack Growth feature introduces a mesh-based tetrahedron that simplifies the process of modeling crack growth. After completing the pre-meshed crack requirements, engineers can select the type of crack growth they want to simulate. The sphere of influence technique refines the mesh around the crack tip, focusing on the geometric edge that passes through the material thickness. This approach enhances accuracy and efficiency in fatigue crack growth analysis. Whether it is Mode I dominant fatigue or static crack growth, ANSYS empowers engineers to explore fracture behavior with precision [102; 103; 104]. Certainly, ANSYS SMART Crack Growth offers several advantages for modeling fatigue crack growth:  
* Efficiency and Cost-Effectiveness: Traditionally, fatigue crack growth analysis involved extensive physical testing, which could be both time-consuming and expensive. However, with advancements in numerical simulation techniques, engineers and researchers now have a powerful tool at their disposal to predict and analyze crack behavior in a more efficient and cost-effective manner [98]. * Mesh-Based Tetrahedron Approach: ANSYS introduces the Smart Crack Growth mesh-based tetrahedron, which simplifies the modeling process. After completing the mesh, you can add the pre-meshed crack requirement, allowing you to select the type of crack growth. The sphere of influence process refines the mesh around the crack tip, enhancing accuracy. * Multiple Crack Support: ANSYS SMART Crack Growth supports multiple cracks, allowing you to analyze complex structures with multiple crack fronts [105]. * Static and Fatigue Crack Growth: It enables both static crack growth analysis using J-integral and Stress-Intensity Factors (SIFs), as well as fatigue crack growth analysis with fatigue crack growth laws [106; 107]. * Automatic Crack Initiation and Growth Arrest: The tool automatically handles crack initiation and growth arrest, streamlining the simulation process [108]. * Cohesive Zone Modeling (CZM) Element Support: For growing cracks, the method assumes that the discontinuities cut the element fully. As the crack grows, newly introduced crack segments are assumed to have cohesive zone behavior.