Calculate volumetric flow rate based on pipe diameter and velocity.
inches
ft/sec
Flow Rate (GPM):–
Flow Rate (Liters/min):–
Flow Rate (m³/hour):–
Cross-Sectional Area:–
function calculateFlowRate() {
// Get inputs
var diameterInput = document.getElementById("pipeDiameter").value;
var velocityInput = document.getElementById("flowVelocity").value;
// Validate inputs
if (diameterInput === "" || velocityInput === "" || isNaN(diameterInput) || isNaN(velocityInput)) {
alert("Please enter valid numbers for both Pipe Diameter and Velocity.");
return;
}
var diameter = parseFloat(diameterInput);
var velocity = parseFloat(velocityInput);
if (diameter <= 0 || velocity < 0) {
alert("Please enter positive values.");
return;
}
// Calculation Logic
// 1. Convert Diameter (inches) to Radius (feet)
// diameter in inches / 12 = diameter in feet
// radius = diameter in feet / 2
var diameterFeet = diameter / 12;
var radiusFeet = diameterFeet / 2;
// 2. Calculate Cross-Sectional Area (A = pi * r^2) in square feet
var areaSqFt = Math.PI * Math.pow(radiusFeet, 2);
// 3. Calculate Volumetric Flow Rate (Q = A * v) in cubic feet per second (CFS)
var flowCFS = areaSqFt * velocity;
// 4. Conversions
// 1 Cubic Foot = 7.48052 Gallons
// CFS to GPM (Gallons Per Minute) = CFS * 7.48052 * 60
var flowGPM = flowCFS * 7.48052 * 60;
// GPM to LPM (Liters Per Minute)
// 1 Gallon = 3.78541 Liters
var flowLPM = flowGPM * 3.78541;
// LPM to Cubic Meters per Hour (m3/h)
// 1 LPM = 0.06 m3/h
var flowM3H = flowLPM * 0.06;
// Display Results
document.getElementById("resGPM").innerHTML = flowGPM.toFixed(2) + " GPM";
document.getElementById("resLPM").innerHTML = flowLPM.toFixed(2) + " L/min";
document.getElementById("resM3H").innerHTML = flowM3H.toFixed(3) + " m³/h";
document.getElementById("resArea").innerHTML = areaSqFt.toFixed(4) + " ft²";
// Show result box
document.getElementById("resultsArea").style.display = "block";
}
Understanding GE Flow Rate Calculations
Whether you are sizing plumbing for a residential property, installing GE appliances like water softeners or filtration systems, or managing industrial piping, understanding the Flow Rate is crucial. This calculator determines the volumetric flow rate based on the physical dimensions of the pipe and the velocity of the fluid moving through it.
The Flow Rate Formula
The fundamental physics equation used in this calculator is Q = A × v, where:
Q = Volumetric Flow Rate (e.g., Cubic Feet per Second)
A = Cross-Sectional Area of the pipe (calculated from the Inner Diameter)
v = Velocity of the fluid
Why Flow Rate Matters for Appliances
Many GE (General Electric) and other brand appliances require specific flow rates to operate correctly:
Water Softeners: Require a minimum flow rate (GPM) for the backwash cycle to effectively clean the resin bed.
Refrigerators: Dispenser lines need adequate flow to fill glasses quickly without splashing or sputtering.
Whole House Filters: Must handle the peak flow rate of the home (often 10-15 GPM) to prevent pressure drops.
How to Use This Calculator
Measure Pipe Diameter: Enter the internal diameter (ID) of your pipe in inches. For standard Schedule 40 PVC, the ID is slightly different from the nominal size, but the nominal size is often a close enough approximation for general estimates.
Estimate Velocity: Typical residential water velocity is between 5 to 10 ft/sec. Velocities above 10 ft/sec can cause noise and pipe erosion, while very low velocities may allow sediment to settle.
Review Results: The calculator provides the flow rate in Gallons Per Minute (GPM), Liters Per Minute (LPM), and Cubic Meters per Hour (m³/h).
Typical Flow Rate Reference
Shower Head: 1.5 – 2.5 GPM
Kitchen Faucet: 1.5 – 2.2 GPM
Garden Hose (1/2″): 5 – 10 GPM (depending on pressure)
GE Water Softener (Backwash): Typically 2.0 – 5.0 GPM depending on the model size.