What occurs to the velocity of supersonic air when it flows through a divergent nozzle?

When supersonic air flows through a divergent nozzle, its velocity increases. This phenomenon can be attributed to the principles of fluid dynamics and the behavior of gases within different nozzle types.

In a divergent nozzle, as the cross-sectional area increases, the airflow accelerates due to the conservation of mass. For supersonic flows, the flow expands in the nozzle, which causes a decrease in pressure and, as a consequence, energy conversion that results in an increase in velocity. The enlargement of the nozzle allows the high-energy supersonic flow to expand and continue accelerating. Thus, in the case of supersonic flow, rather than slowing down, the air gains kinetic energy, increasing its velocity as it travels through the divergent section.

Understanding this behavior is crucial for applications in aerodynamics and propulsion systems, such as jet engines, where maximizing the efficiency of the airflow can lead to better performance and effectiveness of the engine.