Fluid pressure is influenced by flow rate due to the Bernoulli principle and the principle of conservation of mass.

As a fluid travels through a pipe, its velocity changes depending on the pipe’s geometry. In areas where the pipe narrows, the fluid’s velocity increases, while it decreases in regions where the pipe widens. According to the Bernoulli principle, this variation in velocity leads to corresponding changes in pressure: as the fluid’s velocity increases, the pressure decreases, and conversely, when the velocity decreases, the pressure increases. This principle explains why a fluid passing through a constriction, such as a nozzle, can generate a high-pressure jet. For a more in-depth understanding, please refer to the relevant principles outlined on the page.

Furthermore, the conservation of mass asserts that the mass flow rate of a fluid must remain constant along a streamline. This implies that when the fluid’s velocity increases in a constricted section, the cross-sectional area of the pipe must decrease to ensure a constant mass flow rate. This reduction in area contributes to an increase in fluid pressure. For additional information on mass conservation and its effects, please see the suggested resources.

Consequently, as the flow rate increases, the fluid’s velocity rises, leading to a decrease in pressure according to the Bernoulli principle. However, this pressure reduction is counterbalanced by the decrease in cross-sectional area, resulting in an overall increase in fluid pressure. Understanding the relationship between flow rate and pressure is crucial for various applications, including the design of fluid systems and the operation of hydraulic devices.