Detached eddy simulation is a hybrid computational fluid dynamics methodology that combines Reynolds-Averaged Navier-Stokes (RANS) and Large Eddy Simulation (LES) approaches. This method applies a RANS formulation in near-wall regions or attached boundary layers and transitions to an LES formulation in detached flow regions or away from walls, aiming to capture large-scale turbulent structures in separated zones while reducing the computational cost compared to full LES. It is particularly effective for simulating flows with massive separation and complex turbulent scales, serving as a key approach in computational fluid dynamics research.