KEP ES749 - 3.7 Gas Combustion Heat

ES749 Flow Computer
17
FlowmeterTemperature
Transmitter
PRINT
5
0
–
TIME
CLEAR
•
MENU
ENTER
HELP
TEMP
4
PRE 1
3
RATE
2
TOTAL
1
GRAND
6
SCROLL
7
PRE 2
8
DENS
9
Pressure
Transmitter
3.7 Gas Combustion Heat
Measurements:
A owmeter measures the actual volume ow in a gas line. Temperature and pressure
sensors are installed to measure temperature and pressure.
Calculations:
• Density, mass ow and combustion heat are calculated using gas characteristics stored
in the ow computer.
• With square law device measurement the actual volume is calculated from the
differential pressure, taking into account temperature and pressure compensation.
Output Results:
• Display Results
Heat, Mass or Volume Flow Rate, Resettable Total, Non-Resettable Total,
Temperature, Pressure, Density (optional: peak demand, demand last hour,
time/date stamp)
• Analog Output
Heat, Mass or Volume Flow Rate, Temperature, Pressure, Density, Peak
Demand, Demand Last Hour
• Pulse Output
Heat, Mass or Volume Total
• Relay Outputs
Heat, Mass or Volume Flow Rate, Total, Pressure, Temperature Alarms, Peak
Demand, Demand Last Hour
Applications:
Calculate the energy released by combustion of gaseous fuels.
GAS COMBUSTION
HEAT
Combustion Heat Flow
P T
ref
Z
ref
Combustion Energy = C • ρ
ref
• Q • • •
P
ref
T Z
C = Specic combustion heat
ρ
ref
= Reference density
Q = Volume ow
Calculations
Gas Combustion
Heat