This calculator helps you determine the flow rate of a fluid through a pipe or channel. The flow rate is a crucial parameter in many engineering and scientific applications, indicating how much volume of fluid passes a point per unit of time. It is commonly expressed in units like liters per minute (L/min), cubic meters per hour (m³/h), or gallons per minute (GPM).
Minute
Hour
Second
Liters
Cubic Meters
US Gallons
function calculateFlowRate() {
var diameter = parseFloat(document.getElementById("pipeDiameter").value);
var velocity = parseFloat(document.getElementById("fluidVelocity").value);
var timeUnit = document.getElementById("timeUnit").value;
var volumeUnit = document.getElementById("volumeUnit").value;
var resultElement = document.getElementById("result");
resultElement.innerHTML = ""; // Clear previous results
if (isNaN(diameter) || isNaN(velocity) || diameter <= 0 || velocity < 0) {
resultElement.innerHTML = "Please enter valid positive numbers for diameter and velocity.";
return;
}
// Calculate the cross-sectional area of the pipe (Area = pi * r^2)
var radius = diameter / 2;
var area = Math.PI * radius * radius; // Area in square meters
// Calculate the volumetric flow rate in cubic meters per second
var flowRate_m3_per_s = area * velocity;
var conversionFactor_time = 1;
if (timeUnit === "minute") {
conversionFactor_time = 60;
} else if (timeUnit === "hour") {
conversionFactor_time = 3600;
}
var flowRate_m3_per_time_unit = flowRate_m3_per_s * conversionFactor_time;
var finalFlowRate = flowRate_m3_per_time_unit;
var finalVolumeUnit = "m³";
if (volumeUnit === "liter") {
finalFlowRate = flowRate_m3_per_time_unit * 1000; // 1 m³ = 1000 liters
finalVolumeUnit = "L";
} else if (volumeUnit === "gallon") {
finalFlowRate = flowRate_m3_per_time_unit * 264.172; // 1 m³ ≈ 264.172 US gallons
finalVolumeUnit = "GPM"; // Assuming we want Gallons Per Minute if timeUnit is Minute. If not, adjust label.
if (timeUnit === "hour") {
finalVolumeUnit = "GPH";
} else if (timeUnit === "second") {
finalVolumeUnit = "GPS";
}
} else {
// If volumeUnit is cubic_meter, no conversion needed for volume
}
resultElement.innerHTML = "The calculated flow rate is: " + finalFlowRate.toFixed(2) + " " + finalVolumeUnit + "/" + timeUnit + "";
}