Created By : Vaibhavi Kumari

Reviewed By : Phani Ponnapalli

Last Updated : May 15, 2023

The Flow Rate Calculator is a free tool that calculates a fluid's flow rate based on its diameter and velocity. To easily compute the flow rate, simply enter the diameter and velocity in the appropriate input sections and press the calculate button.

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What is Flow Rate?

When we talk about flow rate, we're usually referring to volumetric flow rate. The volumetric flow rate is the volume of a fluid that travels through a certain cross-sectional area per unit of time. The symbol Q, and at times V-V, stands for Volumetric Flow Rate. V/t = Volumetric Flow Rate

Another Flow Rate notion is Mass Flow Rate, sometimes known as Mass Current. It is the mass that goes through a particular cross-sectional area in a given amount of time in this situation. = m/t = mass/time

Flow Rate Formula

Volumetric Flow Rate: To calculate the Volumetric Flow Rate, first determine the volume of a piece of the fluid in the channel. Volume = A*I, where A is the fluid's cross-sectional area and I is the breadth of a specific fluid segment. The Volumetric Flow Rate Equation is obtained by substituting the volume in the Flow Rate Formula. V / t = A * I / t

We refer to I/t as flow velocity because it is the volume length divided by time. As a result, the formula for the volumetric flow rate is A * v. Because the majority of pipes are cylindrical, the equation for Volumetric Flow Rate will be Volumetric flow rate for cylindrical pipe = π * (d/2)² * v, where d is the pipe's diameter. This equation can even be rearranged to determine the pipe velocity.

Mass Flow Rate: To determine the mass rate formula, we must first recall the density definition, i.e. = m / V, which we may rewrite as m = *V. The mass of a material passing per unit time is known as mass flow rate. Mass flow rate = m / t = ρ * V / t = ρ * Volumetric flow rate = ρ * A * v. As a result, Mass Flow Rate = ρ * A * v

For more concepts check out to get quick answers by using this free tool.

Flow Rate Examples

Question 1: Calculate the flow rate of a fluid that is travelling at 50 m/s and has a diameter of 0.04m.



Velocity = 50 m/s

Diameter = 0.04m

Volumetric flow rate = π * (d/2)² * v

Volumetric Flow Rate = π * (0.04/2)² * 50 = 0.0628 Cubic Meter Per Second(m³/s)

FAQs on Flow Rate Calculator

1. What is the average flow rate?

At 32°F, the normal flow rate is 1 atmosphere (101.3 kPa) or 14.696 psi (0 0C). The volume of fluid that travels at a specific site at a certain pressure and temperature is referred to as the actual flow rate.

2. How can you find out how much water is flowing via a pipe?

The square root of 4 times the flow rate divided by pi times velocity is the equation for pipe diameter.

3. What is the formula for calculating the flow rate via a filter?

To get the volumetric flow rate in gallons per minute, multiply the filter's surface area by the velocity of the water passing through it.

4. Does the size of the pipe have an impact on the flow rate?

Flow velocity is inversely proportional to the pipe's t cross-sectional area at any given flow rate. Smaller pipes will result in faster flow rates, while larger pipes will result in slower flow speeds.

5. What is the definition of air flow rate?

The actual volume of air moving through the device per unit of time, stated in cubic feet per minute, to three significant numbers, is referred to as the airflow rate.

6. Is the flow rate affected by the radius?

No. When the diameter of the pipe is increased, the flow rate/discharge increases. The square of the volumetric flow rate, given by the Bernoullis principle, is proportional to the diameter to the fifth divided by the friction factor for a given pressure drop, mass density, and effective length.