17  πŸ’¨ Emission

Emission model based on the ICAO emission databank. Uses the Boeing Fuel Flow Method 2 (BFFM2) for altitude corrections.

17.0.1 Emission(ac, eng=None, backend=None)

Create an emission model instance.

Parameter Type Unit Description
ac str - ICAO aircraft type (e.g. β€œA320”)
eng str, optional - Engine type. Default: aircraft’s default engine
backend MathBackend, optional - Computation backend. Default: NumpyBackend

Fuel-proportional emissions

These methods only need fuel flow as input (no altitude correction):

17.0.2 co2(ffac)

Compute CO2 emission.

Parameter Type Unit Description
ffac float/array kg/s Total fuel flow for all engines

Returns: CO2 emission (g/s)

17.0.3 h2o(ffac)

Compute H2O emission.

Parameter Type Unit Description
ffac float/array kg/s Total fuel flow for all engines

Returns: H2O emission (g/s)

17.0.4 soot(ffac)

Compute soot emission.

Parameter Type Unit Description
ffac float/array kg/s Total fuel flow for all engines

Returns: Soot emission (g/s)

17.0.5 sox(ffac)

Compute SOx emission.

Parameter Type Unit Description
ffac float/array kg/s Total fuel flow for all engines

Returns: SOx emission (g/s)

Altitude-corrected emissions

These methods use BFFM2 to correct for altitude effects:

17.0.6 nox(ffac, tas, alt=0, dT=0)

Compute NOx emission.

Parameter Type Unit Description
ffac float/array kg/s Total fuel flow for all engines
tas float/array kt True airspeed
alt float/array ft Altitude. Default: 0
dT float/array K ISA temperature deviation. Default: 0

Returns: NOx emission (g/s)

17.0.7 co(ffac, tas, alt=0, dT=0)

Compute CO emission.

Parameter Type Unit Description
ffac float/array kg/s Total fuel flow for all engines
tas float/array kt True airspeed
alt float/array ft Altitude. Default: 0
dT float/array K ISA temperature deviation. Default: 0

Returns: CO emission (g/s)

17.0.8 hc(ffac, tas, alt=0, dT=0)

Compute HC emission.

Parameter Type Unit Description
ffac float/array kg/s Total fuel flow for all engines
tas float/array kt True airspeed
alt float/array ft Altitude. Default: 0
dT float/array K ISA temperature deviation. Default: 0

Returns: HC emission (g/s)

Example:

from openap import FuelFlow, Emission

# Create fuel flow and emission models
fuelflow = FuelFlow("A320")
emission = Emission("A320")

# Flight conditions at cruise
mass = 60000  # kg
tas = 250     # kt
alt = 30000   # ft

# Compute fuel flow
ff = fuelflow.enroute(mass, tas, alt)
print(f"Fuel flow: {ff:.4f} kg/s")

# Compute CO2 emission (fuel-proportional)
co2 = emission.co2(ff)
print(f"CO2 emission: {co2:.2f} g/s")

# Compute NOx emission (altitude-corrected)
nox = emission.nox(ff, tas, alt)
print(f"NOx emission: {nox:.4f} g/s")
Fuel flow: 0.7848 kg/s
CO2 emission: 2479.99 g/s
NOx emission: 10.3774 g/s