EBSILON®Professional Online Documentation
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Reference line |
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General User Input Values Physics Used Displays Example
This component is only used to display a line value. However, not only can the results already calculated on the line be displayed, but additional line results (e.g. material values) can also be output.
The FTYP switch determines which line result value is stored in RESULT (possibly also in RESULT2).
Like components 46 (value input) and 33 (start value), this component cannot be connected to a line end, but must be placed directly on a line. Component 45 only takes on its correct shape once it has been placed on a line.
Component 45 has no direct influence on the calculation.
However, it can be used as an indicator in order to be able to use any number of line valuesin the adaption polynomial.
Each component 45 in the model that is to be used as such an indicator must be given a unique index in the specification value FIND. This must be a positive integer. The FTYP switch is used to specify the result value of the line to which the indicator should refer. If a mass fraction, a volume fraction or a normalised weight fraction is selected, the desired substance must also be specified in the FSUBST switch.
If such an indicator is defined, reference can be made to it in every adaption polynomial in the model. The syntax is ‘I’, followed by the indicator number entered for FIND. ‘I7’, for example, refers to the value of RESULT of a component 45 with FIND=7.
This reference can also be made via the name of component 45. The syntax is: i[name]
Where ‘Name’ is the name of the corresponding value display (component 45), either with or without context. However, the reference via ‘Name’ can only be made to value displays for which FIND=0 is set (from Release 13 it is no longer necessary to set its FIND index to 0).
Simultaneous access via the name and via the index is not possible.
Access via names facilitates use in macros in particular, as the FIND numbers used within the macro must be adapted when copying macros, as these must be unique across the model.
"Standard“ quantities
In practice, certain quantities are often related to “standard conditions“; depending on the context, different standards are used.
The options for determining the standard conditions (to specify quantities related to standard conditions ) have been further extended in Release 11:
The input for FNORM determines the reference pressure and reference temperature:
Adopting the reference values from the general settings is not reasonable because other results might be generated on another computer.
The flag FNORMW decides if for determining the standard volume only the dry fraction of the gas is to be considered, or if the water fraction is to be taken along.
The flag FNORMO2 enables a conversion to a reference oxygen concentration. There are the following variants:
• FNORMO2=0: Actual O2 concentration is kept, whereby this concentration refers to the dry or humid flue gas depending on the setting of the flag FNORMW.
• FNORMO2=1: the reference concentration is taken over from the model settings, whereby this concentration refers to the dry or humid flue gas depending on the setting of the flag FNORMW.
• FNORMO2=2: the reference concentration is taken from the component specification value O2REF, whereby this concentration refers to the dry or humid flue gas depending on the setting of the flag FNORMW.
• FNORMO2=3: : the reference concentration is taken over from the model settings, whereby this concentration always refers to the dry flue gas, independent of the flag FNORMW.
• FNORMO2=4: the reference concentration is taken from the component specification value O2REF, whereby this concentration always refers to the dry flue gas, independent of the flag FNORMW.
The setting of FNORM is also used for
FTYP=24 (Normalized concentration (wet) at actual O2 concentration). If FTYP = 24 is set, FNORMW and FNORMO2 be hidden.
(Specification of substance necessary in FSUBST.)
FTYP = 24 is equivalent to FTYP = 42 with FNORMW = 0 and FNORMO2 = 0
FTYP= 42: The calculation of the normalized concentration according to the setting: FNORM (see above), FNORMW (wet or dry) and FNORMO2 (see above),
(Substance required in FSUBST)
The calculation of the normalized concentration is carried out the following way:
1. All the water (XH2O) in the flue gas is maintained (FNORM = 0) or all the water (XH2O) is removed (if FNORMW = 1) and the composition normalized to 1 again.
2. Calculation of the specific volume VNORM under standardized conditions from the physical properties function V(P,T)
3. Calculation of the scaling factor (SFAC) for converting to the reference oxygen concentration O2REF according to
4. Calculation of the normalized concentration CN in mg/Nm³ according to
Possible values of the FTYP switch for the type of value display are listed below.
Depending on the line type, not all values are meaningful or usable on every line.
=1: Pressure (absolut)
=2: Temperature
=3: Enthalpy
=4: Mass flow
=5: Power / Heat flow
=6: Net calorific value (LHV)
=7: Water content (mass fraction)
=8: Unit-less value (handled like enthalpy)
=9: Unit-less value (handled like mass flow)
=10: Steam quality /mass fraction of most volatile phase
=11: Air humidity/flue gas lines (relative)
=12: Relative pressure [= absolute pressure - reference pressure ]
=14: Price per unit of time (internal handling like enthalpy)
=15: Current (on electric lines)
=-15: Deprecated: Enthalpy with dimension of electric current
RESULT2 is used to display the phase of the current if this information is available on the line.
=16: Frequency /rotary speed (on shafts and electric lines)
=-16: Deprecated: Enthalpy with dimension of rotary speed
=17: Temperature difference (internal treatment such as enthalpy)
=18: Enthalpy with dimension of price of energy
=19: Enthalpy with dimension for pricec per mass
=20: Voltage (on electric lines only)
RESULT2 is used to display the phase of the voltage if this information is available on the line.
=-20: Deprecated: Enthalpy with dimension of voltage (for compatibility with earlier EBSILON)
=21: Volume flow
=22: Mass fraction (Specification of substance necessary in FSUBST)
with FSUBST=-1 : for salt water lines salt content, for humid air lines water fraction XI , for binary mixture lines fraction XI of the 1st medium
=23: Mole portion (Specification of substance necessary in FSUBST)
=24: Normalized concentration (wet) at actual O2 concentration (Specification of substance necessary in FSUBST)
=25: Mol portion (dry) (Specification of substance necessary in FSUBST)
=27: Mass (as Enthalpy)
=28: Price (as Enthalpy)
=29: Height / Length(as Enthalpy)
=30: Temperature difference (as Enthalpy)
=31: Relative position / fraction (as Enthalpy)
=33: velocity (as Enthalpy)
=34: Degrees sub cooling
=35: Degrees super heating
=36: Geopotential altitude above sea level
=37: Wet bulb temperature
=38: Dew point temperature
=39: Area (as Enthalpy)
=40: Volume (as Enthalpy)
=41: Density/ concentration
=-41: Deprecated: Enthalpy with the dimension of a density / concentration (for compatibility with earlier EBSILON versions)
=42: Normalised concentration according to FNORM, FNORMW and FNORMO2 (Specification of substance necessary in FSUBST)
=43: Emission load (pollutant mass flow in kg/s)
with FSUBST=-1 : for salt water lines salt mass flow, for humid air lines water mass flow, for binary mixture lines mass flow of the 1st medium
=44: Normalised volume flow
The normalised volume flow is calculated according to the setting: FNORM (see above), FNORMW (wet or dry) and FNORMO2 (see above) in the following way:
1. all the water (XH2O) in the flue gas is retained (FNORM=0) or all the water (XH2O) is removed (if FNORMW=1) and the composition is normalised back to 1.
2. calculation of the specific volume VNORM under standard conditions (FNORM) from the material value function V(P,T)
3. calculation of the normalised volume flow VMN according to
VMN = D_DRY * VNORM,
where D_DRY is the mass flow after deduction of the water.
For pipe types without composition (in particular also on water pipes), the total mass flow is taken as the basis.
=45: Heat consumption(as Enthalpy)
=47: Heat transfer coefficient k*A (as Enthalpy)
=48: Angle(as Enthalpy)
=49: Lower calorific value (related to standard volumetric flow)
The standard volumetric flow is set according to the specifications described above (FNORMW =0/1 see FTYP= 44). For the calorific value, it is possible to use the FNCVREF switch to change the definition of the reference temperature for the calorific value. This can either be specified in the component (FNCVREF=0) or the model setting is used (FNCVREF=1).
=50: Boiling temperature to the pressure prevailing on the line
=51: Boiling pressure at the temperature prevailing in the pipe
=52: Standard volume flow according to the ideal gas formula V/VNORM=(T/TNORM)/(P/PNORM)
Ebsilon normally uses the complete material value functions when converting to standard conditions. Any water contained, for example, can also condense. With FTYP=52, the conversion is not carried out using the material value functions, but according to the equation V/VNORM = (T/TNORM) / (P/PNORM) (note setting FNORM 0/1, see FTYP= 44.
=53: Composition of the phases (mass fractions, only for lines with classical composition)
=54: Phase fractions by mole, Composition of the phases (mass fractions, only for lines with classical composition)
=55: Power factor (cos(phi)), phi>0 assumed, only for electric lines
=56: Enthalpy with the dimension of an energy flow per area (e.g. the direct normal irradiance (DNI) of the sun (is mapped internally to the enthalpy)
=57: Phase shift between voltage and current, only on electric lines
=58: SpecificVolume
=59: Torque, only on shafts
The torque M can be displayed on mechanical shafts (FTYP=59). It results from power Q and speed F according to M = Q / (2π*F)
Note: to obtain the torque in Nm in the formula, the power must be entered in W and the speed in 1/s. When using the standard Ebsilon units (Q in kW, F in 1/min), M [Nm] = (30000/ π) * Q [kW] / F[1/min].
If the torque is specified with BT46, for example, this defines the shaft power. This is then calculated using the speed F according to Q = 2π*F*M. In standard Ebsilon units, the formula is Q [kW] = (π/30000)*F[1/min] *M[Nm]
=60: Enthalpy with the dimension of irradiation (energy per area)
With FTYP=60, it is possible to display a value with the dimension ‘Energy per area’. Internally, this value is mapped to an enthalpy.
=61: Entropy
=62: Exergy
=63: Specific heat at constant pressure (cp)
=64: Specific heat at constant volume (cv)
=65: Enthalpy of the boiling liquid (H'(p))
=66: Enthalpy of the saturated vapour (H‘’(p))
=67: Partial pressure of water in air
=68: Saturation pressure of water in air
=69: Dynamic viscosity
=70: Kinematic viscosity
=71: Thermal conductivity
=72: Isentropic exponent
=73: Surface tension
=74: Speed of sound
=75: Latent heat flow (M*NCV0)
=76: Total heat flow (M*(H+NCV0))
=77: Upper calorific value
=78: Saturation factor (like relative humidity, but not limited to 1)
The ‘saturation factor’ was introduced to control the relative humidity to a value of 100 %. This corresponds to the relative humidity for values up to 100 %. Supersaturated air is the ratio of total water to water in the gaseous phase.
=80: Complex current, only on electrical cables, real and imaginary part in RESULT and RESULT2
=81: Complex voltage, only on electrical lines, real and imaginary part in RESULT and RESULT2
=82: Complex resistance (impedance), only on electrical lines, real and imaginary part in RESULT and RESULT2
Summed real and imaginary part of the resistance of the line up to the next merge (FTYP = 82)
=83: Impedance (magnitude and phase), only on electric lines, complex resistance as magnitude and angle
=84: Correction in the lower calorific value (display), (difference to the calorific value calculated from the composition)
=85: Elementary mass fraction
Component 45 can be used for elemental analysis. To do this, set FTYP to 85 and set the desired element under FSUBST.
You can select C (FSUBST=21), H (22), O (23), N (24), S (25), Cl (26), Ar (6), ash (27), Ca (43) and Mg (44). The mass fraction for the respective element is shown.
=86: Elementary mass flow
Component 45 can be used to display the elementary mass flow. To do this, set FTYP to 86 and set the desired element under FSUBST.
The following options are available: see FTYP=85. The mass flow for the respective element is displayed.
=87: Molar mass flow
FTYP=87 can be used to display the molar mass flow (number of moles flowing through per time unit). The same definition is used for the molar mass as for the conductivity value MOLM, i.e. the components given as elemental analysis are also taken into account and ash is identified with SiO2.
=88: Reactive power, only on electric lines
Not only the active power (FTYP = 5), but also the reactive power (FTYP=88) and the apparent power (FTYP=89) can be displayed on electric lines.
=89: Apparent power, only on electric lines
=90: Composition of the phases (mass fractions for all substances)
=91: Composition of the phases (mole fractions for all substances)
=92: Prandtl number
=93: Freezing temperature
FTYP=93 provides the temperature at which the liquid begins to freeze during cooling at the pressure prevailing in the pipe. Below the triple pressure, the temperature is supplied at which the gas begins to resublimate (i.e. change to the solid phase).
=94: Freezing pressure
FTYP=94 provides the pressure at which the transition to the solid phase begins in relation to the temperature prevailing in the pipe. Depending on the fluid, this can happen with increasing or decreasing pressure: while CO2 solidifies with increasing pressure, liquid water freezes when the pressure decreases.
=95: Melting temperature
FTYP=95 provides the temperature at which the solid begins to melt when heated in relation to the pressure prevailing in the pipe. Below the triple pressure, the temperature at which the solid begins to sublimate (i.e. change into the gas phase) is supplied
=96: Melting pressure
FTYP=96 provides the pressure at which the transition from the solid to the liquid phase begins at the temperature prevailing in the pipe.
=97: Specific gas constant
FTYP=97 provides the specific gas constant, which is defined by RS = R / MOLM, where R is the universal gas constant and MOLM is the molar mass.
=98: Real gas factor (compressibility factor)
FTYP=98 provides the real gas factor (also known as the compressibility factor), which is defined by Z = (P * V) / (RS * T), with P=pressure, V=specific volume, RS=specific gas constant, T=temperature [K].
For an ideal gas, Z=1.
The real gas factor therefore makes it possible to estimate how accurate a calculation as an ideal gas is.
=102: H + NCV
Previously, at FTYP=52 the volume flow in the operating point was converted to normalized conditions according to the formula
V/VNORM= (T/TNORM) / (P/PNORM).
This, however, led to undesired results when the volume flow in the operating point was not calculated in ideal gas approximation but e.g. a real gas correction was used.
Therefore the calculation is now carried out independently of the physical properties in the operating point, i.e. the normalized volume flow is now always the volume flow that would flow through the line if the fluid was an ideal gas at normalized conditions:
VNORM = Ri * TNORM / PNORM,
where Ri is the specific gas constant with Ri = R/mmol. R is the universal gas constant R = 8.31441 kJ/(kmol*K) and mmol is the molar mass of the fluid.
The result then no longer depends on the operating point but only on the composition of the fluid.
Solid matters existing in the fluid are neglected. Whether water is to be included in the calculation or not can be adjusted via the flag FNORMW, as before, just as the possible conversion to a certain O2 content.
The modification regarding FTYP=52 also applies to Component 46 (Measured value input).
The types FTYP=53 and FTYP=90 (composition of phases (mass fractions)) behave identically. The index in front of the respective substance name in the listing corresponds to that index in the list of all available substances (see e.g. list of default value FSUBST).
The same applies to the types FTYP=54 and FTYP=91 (composition of phases (mole fractions)).
In Release 12, however, Component 45 can be used to display the compositions in the individual phases. For this, there are the two new types
When one of these types has been selected, the corresponding fractions are output in the three result arrays
The x-axis of these arrays stands for the individual substances according to the numbering in the flag FSUBST, i.e. 1 for N2, 2 for O2, 3 for CO2, …, 86 for laughing gas (N2O). The corresponding fraction is displayed on the y-axis.
Substances that cannot be selected via FSUBST cannot be displayed here either. Moreover, the used library must support the calculation of the phase equilibrium of mixtures, like the Refprop and the LibAmWa library.
As RESULT in Component 45, the total fraction of the gaseous phase is displayed:
The use of FTYP 7 (water content), FTYP 22 (mass fraction) and FTYP 43 (emission load) is also possible with the line types two-phase fluid and binary fluid.
Composition of the Phases
In the case of a mixture in the multiphase range, the individual phases will usually have different compositions. With FTYP=53 and FTYP=54 respectively, the mass fractions and molar fractions respectively of the individual phases can be output as a result array. Previously, this was only possible for the gaseous (array RAXV) and the liquid phase (array RAXL). In Release 15, all five phases that exist in the TREND library are now supported. For this, there are in addition: RAXSOL (for the solid phase), RAXHYD (for the hydrate phase), and RAXLIQ2 (for a second liquid phase with lower density).
The fraction of the gaseous phase is displayed in the result value RESULT, as previously. The result value RESULT2 contains the total of solid and hydrate phase. The difference of the total from RESULT and RESULT2 to 1 is then the fraction of the liquid phases .
Additionally, there is a result array RAMPHAS that displays the mass fraction for each of the phases.
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FTYP |
Switch for type of value display or result value to be output - see list above for permitted values |
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FIND |
Index for adaption polynomials (As of Release 13, it is no longer necessary for access via "Name" |
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FSUBST |
Flag for substance to be controlled =1: N2 =2: O2 =3: CO2 =4: H2O =5: SO2 =6: Ar =7: CO =8: COS =9: H2 =10: H2S =11: CH4 =12: HCl =13: Ethane =14: Propane =15: n-Butane =16: n-Pentane =17: n-Hexane =18: n-Heptane =19: Acetylene =20: Benzene =21: C (elemental) =22: H (elemental) =23: O (elemental) =24: N (elemental) =25: S (elemental) =26: Cl (elemental) =27: Ash =28: Lime (Ca(OH)2) =30: Water (bound) =31: Ash (gaseous) =32: NO =33: NO2 =34: NH3 =35: deprecated Ammonia (liquid) (NH3) =36: deprecated Carbon dioxide (liquid) (CO2) =37: Methanol (CH3OH) =38: deprecated Water (H2O) =39: Neon (Ne) =40: Dry Air
further material properties No. 41 - No. 2400
Further substances of a composition can be found on the surface of the value display default value "FSUBST" Obviously, or entering two to three significant letters of the desired material value is sufficient to obtain a targeted selection of material values.
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FNORM |
Flag to define a combination of reference pressure and reference temperature =0: EBSILON default (1bar, 15°C) =1: DIN 1343 (1.01325bar, 0°C, often used for Nm3) =2: ISO 2533 (1.01325bar/ 14.696 psia, 15°C/ 59° F, often used for SCM (standard cubic meter)) =3: DIN 1945 (1bar, 20°C) =4: 1bar, 0°C (used for stream result MGNM3) =5: 1.01325bar, 20°C (German TA Luft) =6: 14.696psia, 60F (often used for SCF( standard cubic feet )) =-1: Use measurement points for reference pressure and temperature =-2: Do not normalize but use actual pressure and temperature |
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FNORMW |
Flag to define treatment of water concentration =0: Keep actual water concentration ('wet') =1: Neglect actual water concentration ('dry') |
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FNORMO2 |
Flag to define scaling to reference O2 concentration =0: Keep actual O2 concentration (no scaling) =1: Scale to (wet) molar O2 concentration from model settings =2: Scale to (wet) molar O2 concentration as specified in O2REF =3: Scale to dry molar O2 concentration from model settings =4: Scale to dry molar O2 concentration as specified in O2REF |
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O2REF |
Reference O2 concentration (molar) used for scaling |
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FNCVREF |
Flag to define reference temperature for net calorific value =0: By specification value TNCVREF =1: By stream/model settings |
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TNCVREF |
Reference temperature for net calorific value |
The calculation of the normalized concentration is carried out the following way:
1. The entire water (XH2O) from the flue gas is removed and the composition is standardized to 1
2. Calculation of the specific volume VNORM under standardized conditions from the physical properties function V(P,T)
3. Calculation of the scaling factor for converting to the reference oxygen concentration O2REF according to
= (O2AIR - O2REF) / (O2AIR - O2ACT),
with O2AIR=0.2094615993 and O2ACT= current volume fraction O2 in the dry flue gas
4. Calculation of the normalized concentration CN in mg/Nm³ according to CN = 10^6 * X_I * SFAC / VNORM
The calculation of the normalized volume flow is carried out the following way:
1. The entire water (XH2O) from the flue gas is maintained (if FNORM = 0) or removed (if FNORW = 1) and the composition is standardized to 1.
2. Calculation of the specific volume VNORM under standardized conditions from the physical properties function V(P,T)
3. Calculation of the normalized volume flow VMN according to VMN = D_DRY * VNORM,
where D_DRY is the mass flow after removal of the water.
For line types without composition (particularly also for water lines), the entire mass flow is taken as a basis.
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No equations
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Display Option 1 - not connected to a pipe |
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Display Option 2 - connected to a pipe |
Click here >> Component 45 Demo << to load an example.
