A gradual converging cross-sectional area in ductwork will cause an increase in which property of an air mass?

In ductwork, a gradual converging cross-sectional area influences the properties of the air mass traveling through it. When the cross-section of the duct narrows, the air mass must move faster to maintain the same flow rate. This phenomenon is explained by the principle of continuity, which states that for a given volume flow rate, if the area decreases, the velocity of the fluid must increase to compensate.

As the area converges, the velocity of the air mass increases, which is a fundamental concept in fluid dynamics. According to Bernoulli's principle, as the velocity of a fluid increases, the kinetic energy of that fluid increases while its static pressure decreases. This understanding is crucial for various applications in HVAC systems and pneumatic systems, where managing airflow is essential for efficiency and performance.

The other properties—pressure, temperature, and density—do not inherently increase in this situation. While pressure may vary along with velocity changes, in this specific context of a gradual convergence, the direct result is primarily an increase in velocity.