Component 161: (Injection with temperature control)

Specifications

Line connections
1	Steam inlet
2	Steam outlet
3	water (liquid)
4	Corrected variable (actual value)

General User Input Values Characteristic Lines Physics Used Display Example

General

This component serves to model a controlled injection. It represents a combination of Components 38 (Water injection) and 39 (Controller with internal target value).

The special feature of this component is the actual value pin (Pin 4). From there, an actual value line can be dragged to any position in the model where a desired temperature is to be achieved. Thus by means of this component it is possible to set a temperature that is not present at the component itself.

The specification value TSCV serves to define which temperature is to be set. With the flag FTSCV, you can select whether you want to directly enter the temperature (FTSCV = 0) or a super heating (FTSCV = 1) or a super cooling (FTSCV = -1).

Internally, Component 161 works like a controller. The change of the values during the iteration can be observed by means of the controller process diagram, which is available in the context menu (right mouse button). In the event of trouble with the convergence, the corresponding tuning measures are available.

As a mass flow is varied here at all times in order to set a temperature, there are no flags for this. The flag FCHAR for setting the characteristic does exist but is set to 0 by default because the component tries to automatically determine the characteristic:

If the injected fluid can evaporate, it is assumed that the characteristic is negative, i.e. an increase in the spray flow will always lead to a cooling.
Otherwise the characteristic will be set to positive if the injected fluid is warmer than the main inlet flow, otherwise negative.

If this does not apply or the situation is more complex, the characteristic can also be specified manually though.

User Input Values

FFU	ON / OFF / SET start-value Like in Parent Profile (Sub Profile option only) expression = 1: ON: Controller active = 0: SET: The start value is set, no regulation = -1: OFF: no start value, no regulation = 4: On in design, SET in off-design = -4: ON in design, OFF in off-design = 5: SET in design; ON in off-design = -5: OFF in design, ON in off-design = -6: SET in design, OFF in off-design = -7: OFF in design, SET in off-design
FTSCV	Method for specification of requested temperature at pin 4 Like in Parent Profile (Sub Profile option only) expression =0: TSCV = Requested temperature =1: TSCV = Requested super heating =2: TSCV = Requested sub cooling
TSCV	Scheduled value for temperature specification
L3MIN	Minimum injection mass flow
L3MAX	Maximum injection mass flow
L3START	Start value for injection mass flow
L3STARTOFF	Start value in case off FFU=SET (optional)
FCHAR	Controller characteristic Like in Parent Profile (Sub Profile option only) expression =0: Automatically determined =1: positive =-1: negative
FACT	Controller start at iteration Like in Parent Profile (Sub Profile option only) expression =0: (Immediate start) =20: 20 =40: 40 =50: 50 =100: 100 =-1: Deprecated (Controller deactivated start value set) =-2: Deprecated (Controller completely deactivated)
FDAMP	Controller damping Like in Parent Profile (Sub Profile option only) expression =1: Without =2: very little =3: Little =4: Medium =5: Medium high =6: High =7: Very high =8: Very very high =9: Even higher =10: Extremely high
ITCHL3	Iteration step when CHL3 becomes active
CHL3	Max. change factor of corr. value
ITSTEP	Controller is active every n-th step
FSEQ	Position in calling sequence Like in Parent Profile (Sub Profile option only) expression =0: Parallel to other components =1: Late, after fluids are recalculated
FTOL	Meaning of TOL Like in Parent Profile (Sub Profile option only) expression =0: (not used) =1: TOL = lower limit: Controller is working only as long as relative deviation > TOL =2: TOL = upper limit: relative deviation must be < TOL before iteration stops
TOL	Controller tolerance
FMODE	Transfer of calculated value of controlled variable to start value Like in Parent Profile (Sub Profile option only) expression =0: after calculation in design mode =1: No =-1: After each calculation
FTABC	Material table conversion point Like in Parent Profile (Sub profile option only) expression =0:For all the water at outlet temperature and total pressure (old mode) =1:For gaseous fraction of water after expansion to partial pressure =2:Table difference calculated by Kernel expression EDHTAB
EDHTAB	Function for table difference

The parameters marked in blue are reference quantities for the off-design mode. The actual off-design values refer to these quantities in the equations used .

Generally, all inputs that are visible are required. But, often default values are provided.

For more information on colour of the input fields and their descriptions see Edit Component\Specification values

For more information on design vs. off-design and nominal values see General\Accept Nominal values

Results

RSCV	Target value
RACT	Actual value
RCORR	Corrected variable
RCH3	Last change in corrected variable
ITNOTCONV	Last iteration step where controller prevented convergence
XIL2	Liquid fraction of injection fluid at outlet / M3
XIV2	Gaseous fraction of injection fluid at outlet / M3
XL2	Liquid fraction of injection fluid at outlet / M2
X2	Gaseous fraction at outlet / M2 (=1-XIL2)
RM3M2	Relative mass flow stream 3 to stream 2
PTABV	Pressure of table transition point for the vapour phase
TTABV	Temperature of table transition point for the vapour phase
H3TABV	Enthalpy of injection table transition point for the vapour phase
H2TABV	Enthalpy of target table at transition point for the vapour phase
HDIFFV	Used table difference for the vapour phase
PTABL	Pressure of table transition point for the liquid phase
TTABL	Temperature of table transition point for the liquid phase
H3TABL	Enthalpy of injection table at transition point for the liquid phase
H2TABL	Enthalpy of target table at transition point for the liquid phase
HDIFFL	Used table difference for the liquid phase
HDIFFTOT	Used table difference (total)
DH2UNC	Uncertainty in outlet enthalpy due to handling of liquid fraction as gas (FTABC=1 only)

Characteristic Lines

Characteristic Line CCHL3: Correction Factor for CHL4: CHL4 usesd/specified)= f(Iteration step)

X-Axis      1        Iteration step             0
                  2        Iteration step           20
                    3        Iteration step           40
                    4        Iteration step           60
                    5        Iteration step         100
                    6        Iteration step          150
                    7        iteration step       200
                    8        iteration step       300
                    9        iteration step       500
                   10     iteration step       100000

Y-Axis      1        CHL4                       1
                    2        CHL4                       1
                    .
                   10       CHL4                       1

Physics Used

Equations

Component Displays

Display Option 1

Display Option 2

Example

Click here >> Component 161 Demo << to load an example.

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