Fuel Injector Duty Cycle Calculator
Estimate required injector duty from an entered fuel mass demand, liquid density and nominal per-injector volumetric flow.
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Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Convert nominal volumetric flow to mass capacity and divide the required mass rate by total continuous capacity.
Capacity kg/h=count×flow mL/min×60×10⁻⁶×density; duty=demand/capacity
Worked example
Four 500 mL/min injectors at 750 kg/m³ supply 90 kg/h continuously. A 60 kg/h demand gives duty 66.6666667% and ideal one-pulse duration 13.3333333 ms at 6000 rpm.
Assumptions and input details
Flow rating must apply at the actual differential pressure and fuel. Assumes one injection event per two crank revolutions and linear static flow; dead time, minimum pulse, transients and pressure correction are excluded. Above-100% duty is displayed as an infeasible capacity arithmetic result, not clipped.
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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