Flow - Mass Converter

Mass Flow Rate (symbolized by ˙m or m˙) measures the total mass of fluid or granular material passing through a cross-sectional boundary per unit of time (˙m = dm ÷ dt = ρ · Q = ρ · A · v, where ρ is fluid density, A is cross-sectional conduit area, and v is mean flow velocity). Unlike volumetric flow rates (which expand or contract with temperature and pressure changes), mass flow rate is strictly conserved across control volumes, making it the fundamental metric in commercial aviation jet engine fuel consumption, utility steam boiler feedwater metering, chemical reactor stoichiometry, petroleum refinery cracking, natural gas Custody Transfer metering, and rocket engine thrust propulsion. Units are categorized across three major industrial families: International System of Units (SI metric fundamental: Kilograms per Second / kg/s, Grams per Second / g/s, Kilograms per Hour / kg/h, Metric Tons per Hour / t/h, Metric Tons per Day / t/d), Imperial / US Customary standards (Pounds per Second / lb/s, Pounds per Minute / lb/min, Pounds per Hour / lb/h, Short Tons per Hour / ton(US)/h), and high-capacity bulk transport metrics (Megagrams per Second / Mg/s, Gigagrams per Second / Gg/s).

Our free online Flow – Mass Converter provides instant, high-precision conversions across all SI metric, Imperial industrial, aerospace fuel burn, and process engineering mass flow units:

• Kilograms per Second to Pounds per Hour [Aerospace Fuel Burn Standard]: 1 kg/s = 7,936.64144 lb/h = 132.27736 lb/min = 2.2046226 lb/s = 3.60 t/h = 3,600 kg/h.
• Pounds per Hour to kg/s & kg/h [Steam Boiler Standard]: Multiply lb/h by 0.0001259979 (1 lb/h = 0.0001260 kg/s = 0.453592 kg/h = 0.00045359 t/h).
• Metric Tons per Hour to kg/s & lb/h [Heavy Process Standard]: Multiply t/h by 0.27777778 (1 t/h = 0.27778 kg/s = 277.778 g/s = 612.395 lb/h = 1.10231 short ton/h).
• Pounds per Second to kg/s [Rocket Thrust Standard]: Multiply lb/s by 0.45359237 (1 lb/s = 0.453592 kg/s = 1,632.93 kg/h = 3,600 lb/h = 1.63293 t/h).
• Kilograms per Hour to Grams per Second & lb/h: Multiply kg/h by 0.27777778 for g/s (1 kg/h = 0.27778 g/s = 0.00027778 kg/s = 2.20462 lb/h).
• Short Tons per Hour to t/h & lb/h [Mining Conveyor Standard]: Multiply ton(US)/h by 0.25199576 (1 short ton/h = 0.25200 kg/s = 0.907185 t/h = 2,000 lb/h).

Master Mass Flow Rate Conversion Table

The table below displays exact mathematical conversion relationships, SI kg/s multipliers, and imperial lb/h equivalents relative to 1 Kilogram per Second (1 kg/s = 3,600 kg/h):

Step-by-Step Aircraft Jet Engine Fuel Burn Calculation Example

To convert a commercial jet engine (such as a GE90 on a Boeing 777) consuming 1.15 Kilograms per Second (1.15 kg/s) of Jet-A fuel during cruise into Imperial Pounds per Hour (lb/h) and Metric Tons per Hour (t/h):

Step 1 (Imperial lb/h Conversion): ˙m = 1.15 × 7,936.64144 = 9,127.14 lb/h

Step 2 (Metric t/h Conversion): ˙m = 1.15 × 3.60 = 4.14 t/h (4,140 kg/h)

Step 3 (Pounds per Minute Conversion): ˙m = 9,127.14 ÷ 60 = 152.12 lb/min

Thus, at 1.15 kg/s fuel flow, the engine burns 9,127.14 Pounds per Hour or 4.14 Metric Tons per Hour of jet fuel.

Real-World Industrial & Aerospace Mass Flow Rate Benchmarks

Below is a comparative reference chart showing mass flow rates (˙m) across dosing pumps, automotive engines, jet turbines, power plant boilers, and orbital rockets:

History & Physics: 1750 Euler Mass Continuity vs 1970s Coriolis Direct Mass Flowmeters

1750 Leonhard Euler & the Conservation of Fluid Mass (˙m = ∫ ρ v dA)

In 1750, Swiss mathematician Leonhard Euler published the differential field equations of fluid dynamics, establishing the universal law of mass conservation: ∂ρ ÷ ∂t + ∇ · (ρ v) = 0. Euler proved that mass flow rate (˙m = ρ · A · v in kg/s) is strictly conserved in any closed conduit, forming the foundation of modern process thermodynamics.

1970s Coriolis Mass Flow Meter Invention (Direct Mass Measurement)

Until the 1970s, industrial mass flow was calculated indirectly by measuring volumetric flow and density separately. In the 1970s, commercialization of Coriolis Mass Flow Meters (utilizing the Coriolis force FC = -2m(ω × v)) revolutionized chemical metering. By vibrating a fluid tube and measuring the phase twist angle, Coriolis meters measure true mass flow rate (˙m) directly in kg/s or lb/h, unaffected by fluid viscosity, temperature, pressure, or bubbles.

Popular direct tools:

• Conversion Calculator Main Directory
• Flow Converter (Volumetric)
• Mass Converter

Frequently Asked Questions (FAQ)

How do you convert kg/s to lb/h?

To convert Mass Flow Rate from kg/s to lb/h, multiply kg/s by 7,936.64144 (or multiply by 3,600 to get kg/h, then multiply by 2.2046226). For example, 1.0 kg/s × 7,936.64 = 7,936.64 lb/h.

How do you convert lb/h to kg/s?

To convert Pounds per Hour (lb/h) to kg/s, multiply lb/h by 0.0001259979 (or divide by 7,936.64). For example, 10,000 lb/h × 0.0001259979 = 1.260 kg/s.

How do you convert Metric Tons per Hour (t/h) to kg/s?

To convert Metric Tons per Hour (t/h) to kg/s, divide t/h by 3.6 (or multiply by 0.27777778). For example, a plant processing 360 t/h ÷ 3.6 = 100.0 kg/s.

Why is Mass Flow Rate preferred over Volumetric Flow Rate in processing?

Unlike volumetric flow rates (which vary when gases expand under heat or liquids change density), mass flow rate is conserved. Chemical reactions and combustion require exact mass ratios of reactants regardless of temperature or pressure.