What is the movement of liquids in a cargo tank called?

The movement of liquids in a cargo tank is referred to as "surge." This phenomenon occurs when the liquid inside the tank shifts due to changes in speed, acceleration, or deceleration of the vehicle, as well as changes in direction. As a vehicle turns or comes to a stop, the inertia of the liquid causes it to move forward, backward, or sideways within the tank, creating waves or shifts. This movement can affect the stability of the vehicle and can pose safety risks during transport.

Understanding surge is crucial for drivers of vehicles carrying hazardous materials since it impacts how the cargo is handled. It helps drivers anticipate handling issues and take appropriate measures to maintain control of the vehicle. Knowledge of surge also relates to the design of cargo tanks, which are often equipped with baffles or other features to minimize the effects of liquid movement.