Object Name Page No.
EndEnviromnent 54
Fstatelnit 55
FpropGasCombust 56
FpropMixtureCombust 58
FpropLiqIncomp 59
Pipe 61
EngCylinder 63
EngCylGeom 66
VaiveConn 68
InjProfileConn 69
. InjRateConn 73
EngCyIHeatTr 74
EngCylCombDIWiebe 76
EngineCrankTrain 78
EngFrictionCF 80
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EndEnvlronment
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Flow Component
End Environment
This object describes end environment boundary conditions of pressure, temperature, and composition.
Pressure Temperature Pressure Flag
Composition
Pressure in the environment or the name of a dependency reference object.
Temperature in the environment or the name of a dependency reference object.
One of the following choices:
• total indicates that the pressure and temperature will be imposed as total (stagnation) conditions at the inlet of the attached flow component. This is the physically meaningful boundary condition that should normally be used.
• static indicates !bat the pressure and temperature will be imposed as static conditions at the inlet of the attached flow component. This boundary condition should only be used when the flow is inll! the system. Because this option can introduce feedback into the flow solution. it should
not
be usedwhen
the pressures just inside the boundary are fluctuating. such as at the inlet manifold of an engine.This option is made available for steady flow tests, such as a simulated flow bench.
Name of an 'FProp.' reference object that defines the composition of the environment.
Configuration: 'EndEnvironment' components must be connected to a single flow component with a flow connection.
Plotted and Sensed Variables:
J/ariqble
Pressure Temperature
Plotted
Sensed• bar
• K
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Fstatelnll Flow Reference
55
FStatelnit • Initial Fluid State
This object is used to specifYthe initial conditions in flow component!;.
Pressure Temperature Composition
Fluid pressure at the start of the simulation.
Fluid temperature at the start of the simulation.
Name of an 'FProp*' reference object that defines the composition at the start of the simulation.
FpropGasCombustFlow Reference
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'FPropGasCombust • GasNapor Properties of Combustible Species
This object is used to describe the properties of combustible gas/vapor species. The composition of all gases (even for non-fuels) must be entered so that their impact on combustion and emissions can be determined. In order to create a "tracer" gas to trace gas flow in a system, the first 4 attributes of this template need to be set to zero. See the tracer example in the OT-Power examples directory to observe the use ofa tracer gas in a OT-Power model.
Carbon Atoms per Molecule Average number of carbon atoms in each molecule of the substance being described.
Hydrogen Atoms per Mol. Average number of hydrogen atoms in each molecule of the substance being described.
Oxygen Atoms per Molecule Average number of oxygen atoms in each molecule of the substance being described.
Nitrogen Atoms per Molecule Average number of nitrogen atoms in each molecule of the substance being described.
Lower Heating Value Lower heating value of the substance. The attribute may be set to "ign"
for all species that do not have carbon or hydrogen atoms. "ign" is also allowed for CO, and H,O.
Critical Temperature Critical temperature of the substance. If the gas should always be modeled as an ideal gas, set this value to a very high number, such as I.OE9 K.
Critical Pressure Critical pressure of the substance. If the gas should always be modeled as an ideal gas, set this value to a very high number, such as I.OE9.
Minimum Valid Temperature Minimum temperature at which the data in the following folders is valid.
This value is used as information only (this number does not affect the simulation results).
iIIIaximum Valid Temperature Maximum temperature at which the data in the following folders is valid.
This value is used as information only (this number does not affect the simulation results).
Minimum Valid Pressure Minimum pressure at which the data in the following folders is valid.
This value is used as information only (this number does not affect the simulation results).
Maximum Valid Pressure Maximum pressure at which the data in the following folders is valid.
This value is used as information only (this number does not affect the simulation results).
EnthalpY
The enthalpy In JIkg of the vapor is determined from the following curve-fit equation where hnf is the enthalpy at the reference temperature, TNfl of 298 K. h", is automatically calculated by the code to be consistent with theL_er Heating Value specified above.
56
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FpropGasCombllOt Flow Reference
57
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h - h,q =
~:a. (r - r,q r
=0,(r -
r,q)+ 0,(r - r,q Y
n""J
Enthalpy Coefficients,
a,. a.
Coefficients 01 through OJthat are used in the enthalpy equation shown above to give the enthalpy over a wide range of temperatures.TempArrays
The properties given below are for the transport properties of the gas. If the code tries to look up a temperature that is less than the lowest temperature or greater than the highest temperature, the nearest value available will be used. (One single line of data may be entered to make the transport properties constant at all temperatures.) The transport properties of air are already known inside the code and will be used if the following three attributes are set to "def'. In simulations where a certain species is only present as a small mass fraction of the total mass, it may be acceptable to use this default option. (If "def' is used, then all three arrays must be set to "def'.)
Temperature Array
Viscosity Array
Conductivity Array
Temperature array in monotonic format. If "def' is entered, the viscosity and temperature of air will be used.
Absolute viscosity, Jl, corresponding to Temperature Array above. If
"def' is entered, the viscosity and temperature of air will be used.
Thermal conductivity corresponding to Temperature Array above. If
"def' is entered, the conductivity and temperature of air will be used.
FpropMixtureCombust.
Flow Reference
58
FPropMixtureCombust - Mixture of Combustible Fluids
This object is used to define mixtures of vapor and/or liquid fluids. For example, a mixture or air can be formed by mixing oxygen and nitrogen that have been defined as 'FPropGasCombust' reference objects.
Furthermore, a mixture of humid air could be formed by mixing the 'FPropMixtureCombust' reference object for air and an 'FPropGasCombust' reference object for vapor water.
Burned Property Flag
Arrays
Cash: n-.lid Object Mass Fraction
One of the following choices:
• noburn indicates that the mixture will be composed of the specified species.
• burn indicates that the specified species should be replaced by the products of combustion produced by burning the specified species.
For example, a mixture of fuel and air will actually be modeled as a mixture of the burned gases carbon dioxide, water vapor, nitrogen, and carbon monoxide (if rich).
An array of 'fPropGasCombust', 'FPropLiqIncomp' or 'FPropMixtureCombust' reference objects that compose the mixture.
An array corresponding to Basic Fluid Object that specifies the mass fraction of each of the fluid objects that compose the mixture. The sum of the mass fractions must be equal to one.
.r
59 FpropLiqlncomp
Flow Reference
FPropLiqlncomp • Incompressible Liquid Properties
This object is used to describe the properties of incompressible liquids. This object is appropriate for use when the liquid is only a small mass fraction of the fluid mixture (i.e. the liquid is mixed with a gas).
Within a given simulation, all 'FPropLiqIncomp' reference objects must have a corresponding 'FPropGasCombust' reference object that gives the composition of the liquid.
Vapor Fluid Object
Minimum Valid PIlISSUIll
Maximum Valid PIlIS8Ulll Density
Minimum Valid Temperatulll
Name of an 'FPropGasCombust' reference object that describes the properties of the liquid after it vaporizes.
Heat of Veporizatlon at 298 K Energy necessary to vaporize a given mass of liquid at a temperature of 298 K into the vapor described above in Vapor Fluid Object.
Density of the liquid.
Minimum temperature at which the data in the following folders is valid.
This value is used as information only (this number does not affect the simulation results).
Maximum Valid Temperatulll Maximum temperature at which the data in the following folders is valid.
This value is used as information only (this number does not affect the simulation results).
Minimum pressure at which the data in the following folders is valid.
This value is used as information only (this number does not affect the simulation results). .
Maximum pressure at which the data in the following folders is valid.
This value is used as information only (this number does not affect the simulation results).
Enthalpy
The enthalpy of the liquid In Jlkg at pressure= I bar is determined from the following curve-fit equation whereTmt =298 K. The reference enthalpy is defined as:h",= (h,.j""",," h"""'rlMII'"
Enthalpy Coefficients, 8," 8. Coefficients OJand0, that are used in the enthalpy equation shown above to give the enthalpy over a wide range of temperatures.
TempArrays
The properties given below are for the transport properties of the liquid. If the code tries to look up a temperature that is less than the lowest temperature or greater than the highest temperature, the nearest value available will be used. (One single line of data may be entered to make the transport properties constant at all temperatures.) The transport properties of air are already known inside the code and will be used if the following three attributes are set to "def'. In simulations where a certain species is only present as a small mass fraction of the total mass, it may be acceptable to use this delilult option. (If "def' is used, then all three arrays must be set to "def'.)
Temperature Array Viscosity Array Conductivity Array
60 FpropLiqlncomp
Flow Referenc&
Temperature array in monotonic fonnat. If"def' is entered, the viscosity and temperature of air will be used.
Absolute viscosity, JJ, corresponding to Temperature Array above. If
"def' is entered, the viscosity and temperature of air will be used.
Thennal conductivity corresponding to Temperature Array above. If
"def' is entered, the conductivity and temperature of air will be used.
Flow
compo~= I ?'i:i$\ t1 1
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