Power Generation in a Gas Turbine-Generator: Oper. Conds Tab

Variable Definitions, Ranges and Default Values

The following table shows a brief description of the variables appearing in this tab. The table also displays their default values and their generally acceptable range.

Variable	Default Value	Range

○ Air Stream Indicates the input port that is connected to the air stream. If an input stream is already present at the selected port, then the button next to the selection is active. Click on the button to bring up the attached stream’s simulation dialog in order to provide its composition.	<None>	Designated Air Stream
● Relative Humidity (%) The relative humidity of the inlet air stream.	0.0	Positive
◙ Excess Oxygen (%) The excess oxygen % of the air stream.	200.0	Positive
◙ Air-Fuel Ratio The ratio of the mass flowrate of the air stream to the mass flowrate of the fuel stream.	0.0	Positive
● Stoichiometric Air-Fuel Ratio The minimum air-fuel ratio required for stoichiometric combustion.	0.0	Positive
● Air Throughput per Unit The volumetric flow rate of inlet air per equipment unit.	0.0	Positive
○ Air Compressor Pressure Ratio (-) The ratio of compressor outlet pressure to compressor inlet pressure.	20.0	Positive
○ Air Compressor Isentropic Efficiency (%) The isentropic efficiency of the air compressor.	88.0	0-100
● Air Compressor Power (kW) The total power consumption of the operation to compress air.	0.0	Positive
● Combustion Chamber Outlet Temperature (^oC) The outlet temperature of combustion gas from the combustion chamber.	0.0	Positive
○ Turbine Isentropic Efficiency (%) The isentropic efficiency of the expansion turbine.	90.0	0-100
● Turbine Power (kW) The total mechanical power output of the operation.	0.0	Positive
○ Power Type Indicates the power type that is used by the operation. Click on the list box to bring up a list of available power types in order to select one.	<Std Power>	Any Power Type
● Heat Input (LHV) (kW) The total thermal energy input of the fuel based on LHV.	0.0	Positive
● Net Shaft Power (kW) The total net mechanical power output of the operation (which is equal to the turbine power minus the compressor power).	0.0	Positive
● Thermal Efficiency (%) The percentage of fuel thermal energy input (expressed in terms of LHV) that is converted into mechanical power output.	0.0	0-100
○ Generator Efficiency (%) The electric generator’s efficiency of conversion of mechanical power to electric power.	95.0	0-100
● Electric Power The total electric power output of the operation.	0.0	Positive
● Electrical Efficiency (%) The percentage of fuel thermal energy input (expressed as LHV) that is converted into electrical power output.	0.0	0-100
○ Setup Time The amount of time (per cycle) spent before each operation is carried in preparation for the actual execution of the operation. It may involve actions like cleaning, vacuuming, setting up of equipment, etc. which the user opted not to model explicitly.	0.0	Positive
◙ Process Time (min) The actual duration of the operation (per cycle). It can be either set by user or set by a master-slave relationship.	60.0	Positive
○ Ignore Labor? Check this box to ignore labor for this operation. This option is used only if the process time is set by a master-slave relationship.	Yes	Yes/No

Symbol Key: ○ User-specified value (always input); ● Calculated value (always output); ◙ Sometimes input, sometimes output

Specification Choices / Comments

The following list describes the available specification choices in this tab; for more details on how these are implemented, see Power Generation in a Gas Turbine-Generator: Modeling Calculations.

•Model options...

You may either choose the “detailed” or the “simplified” model. If you choose the “detailed” model, you must specify the compressor efficiency and turbine efficiency. On the other hand, if you choose the “simplified” model, you must specify the gas turbine’s thermal efficiency.

•Duration options...

Duration options are only available in batch mode. You can set the process time, or have the process time calculated based on air throughput, or match the duration of this operation to the duration of another operation by introducing a master-slave relationship between the two operations. If you introduce a master-slave relationship, the program will match the setup time, the process time and the turnaround time of this operation (the ‘slave’) with the corresponding times of the reference operation (the ‘master’ operation). For more details on how to setup a master-slave relationship, see The Scheduling Tab.