• id: JME-09-N09
• title: Venturi Meter and Flow Measurement
• tags: venturi, pitot, flow-measurement

The Venturi meter measures flow speed using a constriction in a pipe. At the constriction, velocity increases (continuity) and pressure decreases (Bernoulli). The pressure difference is measured by a manometer. Formula: $v_1 = A_2\sqrt{2\Delta P / [\rho(A_1^2 - A_2^2)]}$. The Pitot tube measures flow velocity by comparing static and stagnation (total) pressures: $v = \sqrt{2\Delta P/\rho}$, where $\Delta P$ is the difference between stagnation and static pressure. Both devices are direct applications of Bernoulli's equation.