Flow Rate Calculator

The foundational principle behind volumetric flow rate (Q) is the continuity equation, which multiplies the cross-sectional area (A) of a channel by the average fluid velocity (v): Q = A * v. Depending on your system geometry, the area formula adapts. For a full circular pipe, the area is calculated using the diameter (d) as (d/2)^2 * pi. For rectangular channels, it multiplies height by width. When calculating mass flow rate, the volumetric flow rate is further multiplied by the fluid's density (rho). For partially filled pipes, a central angle (alpha) parameter is introduced to compute the exact segment area of the flowing fluid.

Imagine water flowing through a circular pipe with a diameter of 0.2 meters at a velocity of 3 meters per second. First, find the cross-sectional area: A = (0.2 / 2)^2 * pi = 0.0314 square meters. Next, calculate the volumetric flow rate: Q = 0.0314 * 3 = 0.0942 cubic meters per second. If the density of water is 1000 kilograms per cubic meter, the mass flow rate is 0.0942 * 1000 = 94.2 kilograms per second.

Ensure all your measurements use consistent metric or imperial units before performing calculations to avoid conversion errors. When dealing with real-world pipes, remember that internal diameter differs from outer diameter due to wall thickness. Always account for temperature variations when inputting fluid density, as thermal expansion can significantly alter mass flow calculations.