Accelerations in Fluid Flow. What is Tangential Acceleration?

Acceleration of fluid particles is the change in velocity vector of the flow field. For velocity vectors which are the function of space and time the change in velocity vector or the acceleration will be the sum of acceleration in space or convective acceleration due to the change in velocity in space and the acceleration in time or the local acceleration due to the change in velocity in time. Acceleration of fluid particles have two components based on the geometry of the flow, tangential acceleration due to the change in speed of flow along the flow direction and normal acceleration, which is the component of change in velocity normal to the direction of flow.