Internal flow

Internal flow refers to the movement of a fluid (liquid or gas) within a confined space, such as pipes, ducts, or channels. This type of flow is characterized by the fact that the fluid is contained within boundaries, which influences its behavior and the forces acting upon it. Key characteristics of internal flow include: 1. **Geometry**: The flow occurs in a constrained environment, such as cylindrical pipes or rectangular ducts, and is significantly influenced by the shape and size of these boundaries.