A Compound Layers Mesh is a structured or unstructured mesh consisting of multiple layers of elements, often used in computational simulations to model complex materials, fluid dynamics, or structural behaviors. These layers can have different properties, such as varying thickness, material composition, or mesh density.

They are used to improve accuracy in simulations that involve layered materials, such as geological formations, composite materials, or boundary layers in fluid dynamics. By refining the mesh in critical areas while keeping other regions coarse, computational efficiency is enhanced without sacrificing precision.

Challenges include maintaining mesh quality across layers, ensuring smooth transitions between different regions, handling complex geometries, and optimizing the mesh for computational efficiency. Poorly structured layers can lead to numerical instabilities or inaccuracies in simulation results.