What happens to gas velocity in a pipe as the diameter increases, according to Bernoulli's principle?

According to Bernoulli's principle, as the diameter of a pipe increases, the velocity of the gas flowing through it decreases. This relationship arises from the principle of conservation of mass, which asserts that for a fluid flowing in a steady stream, the mass flow rate must remain constant.

In a pipe, the mass flow rate is given by the product of the cross-sectional area of the pipe and the velocity of the fluid. When the diameter of the pipe increases, the cross-sectional area becomes larger. To maintain the same mass flow rate, the velocity of the fluid must decrease because the area available for flow has increased. This phenomenon is commonly observed in fluid dynamics, particularly in applications involving varying pipe diameters, such as converging and diverging flow sections.

So, with an increase in the pipe's diameter, the gas velocity decreases in order to conserve mass, aligning perfectly with Bernoulli's principle.