The Flame Speed Calculator helps estimate how fast a flame moves through a gas mixture during combustion. This is useful in areas like engine design, fire safety, and fuel efficiency research. There are two types of flame speeds: laminar (smooth and steady) and turbulent (chaotic and fast). This calculator provides a way to estimate both.
Formula of Flame Speed Calculator
Where:
SL = Laminar flame speed in meters per second
α = Thermal diffusivity of the unburned gas in square meters per second
Q = Heat released per kilogram of fuel in joules
ρu = Density of the unburned gas in kilograms per cubic meter
cp = Specific heat at constant pressure in joules per kilogram kelvin
Tu = Temperature of the unburned gas in kelvin
For turbulent flame speed:
Turbulent Flame Speed (ST) = SL × (1 + u prime divided by SL) to the power of n
Where:
u prime = Turbulence intensity in meters per second
n = Constant value, usually between 0.5 and 1.0
Common Terms and Reference Table
This table gives typical values people search for and use when they do not have their own measurements.Fuel Type Laminar Flame Speed (m/s) Heat Release Q (J/kg) Notes Methane 0.38 50000000 Used in natural gas Propane 0.46 46400000 Common in burners Hydrogen 2.90 120000000 Very fast flame speed Ethanol 0.40 29700000 Alcohol-based fuel Gasoline 0.40 44000000 Internal combustion engines
Example of Flame Speed Calculator
Suppose you want to calculate the flame speed for methane. Use the following values:
alpha = 0.000022
Q = 50000000
rho_u = 0.65
cp = 1005
Tu = 300
Insert into the formula:
SL = square root of (0.000022 × 50000000 × 0.65) divided by (1005 × 300)
SL = square root of (715000) divided by 301500
SL = square root of 2.37
SL is approximately 1.54 meters per second
Most Common FAQs
Answer: It is the rate at which a flame travels through a gas mixture during burning. It helps in understanding how a fuel burns.
Answer: It helps researchers and engineers design safer and more efficient combustion systems, such as engines and industrial burners.
Answer: Yes, but the liquid must be converted into gas or vapor first. The flame speed is calculated based on gas-phase combustion.