Title 40


Appendix A to Subpart D of Part 91 - Tables

40: : Appendix A

Appendix A to Subpart D of Part 91 - Tables

Table 1 - Symbols Used in Subparts D and E

Symbol Term Unit
AYM Final weighted emission test results g/kW-hr
C3 H8 Propane
CB Concentration of emission in background sample ppm
CD Concentration of emission in dilute sample ppm
CO Carbon monoxide
CO2 Carbon dioxide
conc Concentration (ppm by volume) ppm
DX Density of a specific emission (XX) g/m 3
DXX Volume concentration of a specific emission (XX) on a dry basis percent
DF Dilution factor of dilute exhaust
D1 Water vapor mixture concentration percent
f Engine specific parameter considering atmospheric conditions
GAIRD Intake air mass flow rate on dry basis kg/h
GFuel Fuel mass flow rate kg/h
GP Analyzer standard operating pressure Pa
Gs Mass of carbon measured during a sampling period g
H Absolute humidity (water content related to dry air) gr/kg
H2 Hydrogen
i Subscript denoting an individual mode
IT Indicated torque N-m
K Wet to dry conversion factor
KH Humidity correction factor
KV Calibration coefficient for critical flow venturi
MX Molecular weight of a specific molecule(XX) g/mole
mass Pollutant mass flow g/h
MFUEL Mass of fuel consumed during a sampling period g
N Pump revolutions during test period revs
N2 Nitrogen
NO Nitric oxide
NO2 Nitrogen dioxide
NOX Oxides of nitrogen
O2 Oxygen
O2 I Oxygen concentration of the burner air percent
P Absolute pressure kPa
PAUX Declared total power absorbed by auxiliaries fitted for the test kW
PB Total barometric pressure (average of the pre-test and post-test values) kPa
Pdew Test ambient saturation vapor pressure at the dew point kPa
Pe Absolute pump outlet pressure kPa
PED Pressure drop between the inlet and throat of metering venturi kPa
Pi Pi = PM, i + PAUX,i
PM Maximum power measured at the test speed under test conditions kW
PP Absolute pump inlet pressure kPa
PPI Inlet pressure depression of venturi or pump kPa
PPO Pressure head at CVS pump outlet kPa
Ps Dry atmospheric pressure kPa
PV Absolute venturi inlet pressure kPa
Pwb Saturated vapor pressure Pa
QC Volumetric flow rate of dilute exhaust through CVS at STP m 3/hr
QS Gas flow rate m 3/min
RSTP Ideal gas constant at STP m 3/mole
R2 Fuel carbon weight fraction g/g
STP Standard temperature and pressure
t Elapsed time for test period sec.
T Absolute temperature at air inlet °C
Ta Ambient temperature °C
TEI Air temperature in to metering venturi or flowmeter °C
TK Absolute temperature K
TP Absolute pump inlet temperature °C
TPI Air temperature at CVS pump inlet °C
TPO Air temperature at CVS pump outlet °C
TV Absolute venturi inlet temperature °C
VO Pump flow m 3/rev
W Average mass flow of emissions g/hr
WX Mass rate of specific emission (XX) g/hr
WXX Volume concentration in exhaust of specific emission (XX) on wet basis ppm, ppmC, %
WF Weighing factor
Z1 Water concentration percent
α Fuel specific factor representing the hydrogen to carbon ratio