Component 67: Condenser (Type 2) - Outdated

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Component 67: Condenser with Measurement Input - outdated!

General

This component is available only for ensuring a backward compatibility with the earlier versions of Ebsilon and is not maintained any more. Instead of this component, component 7 should be used in new cycles.

The most commonly used method of calculating the part-load is FSPEC=0. This means the outlet temperature of the cooling medium is calculated by means of the known mass flow of the cooling medium.
The pressure of exhaust steam must be defined via an initial value (pastille).
Sub Cooling of the condensate is not intended. But this can easily be modelled by inserting an after-cooler (component 27)..
Pressure and temperature of the cooling medium (water or air) must be defined e.g. via component 33 (pastille).
Radiation losses can be defined by means of a relative loss factor.
The exhaust steam pressure adjusts in off-design mode in such a way that complete condensation results..
Besides water, air is also allowed as primary medium, so that an air condenser can also be modelled.
The total-(k*A) is the product of the (k*A)-values of both characteristic lines.
The calculated waste steam pressure P3 in case of off-design operation is the one, which results in saturated condensate at given coolant flow rate.
The mass flow of line 5 (auxiliary condensate) must be defined by further information. Normally this value results from the related connection scheme.

Specifications

Line connections
1	Primary inlet
2	Primary outlet
3	Secondary inlet
4	Secondary outlet
5	Secondary inlet for auxiliary condensate

DT3S2N	Upper terminal temperature difference (nominal) DT3S2N=T3Nsat-T2N
FDP12RN	Primary pressure loss handling Like in Parent Profile (Sub Profile option only) Expression =1:Calculated by DP12N=DP12RN (absolute) =2:Calculated by DP12N= P1N*DP12RN (relative)
DP12RN	Pressure loss line 12 (nominal) [absolute or relative to P1]
FDP34RN	Secondary pressure loss handling Like in Parent Profile (Sub Profile option only) Expression =1: Calculated by DP34N=DP34RN (absolute) =2: Calculated by DP34N= P3N*DP34RN (relative)
DP34RN	Pressure loss 34 (nominal) [absolute or relative to P3]
DQLR	Heat loss (relative)
FMODE	Flag for calculation mode Design/Off-design Like in Parent Profile (Sub Profile option only) Expression =0: Global =1: local off-design (i.e. always off-design mode (KAN and characteristic lines), even when a design calculation has been done globally) =2: special local off-design, calculation is analogous to off-design, but without considering the characteristic lines (Special case for compatibility with the earlier Ebsilon-versions, should not be used in new models, because the results of the real off-design calculations are not always consistent)
FFLOW	Direction of flow Like in Parent Profile (Sub Profile option only) Expression =0: counter current flow =1: concurrent flow (permitted only for FMODE>=1)
FSPEC	Specifications Like in Parent Profile (Sub Profile option only) Expression =0: (design) given DT3S2N calculated T2,M1, (off-design) given M1=M1N calculated T2 =1: (design) given DT3S2N calculated T2,M1, (off-design) given T2 calculated M1 =2: (design) given DT3S2N calculated T2,M1, (off-design) given M1 calculated T2 =5: (design) given T2 calculated M1, (off-design) given M1=M1N calculated T2 =15: (design) given T2 calculated M1, (off-design) given T2 calculated M1 =25: (design) given T2 calculated M1, (off-design) given M1 calculated T2
FVOL	Volume dependency on pressure drop Like in Parent Profile (Sub Profile option only) Expression =0: without DP/DPN = (M/MN)*2 =1: with DP/DPN = V/VN(M/MN)**2
FADAPT	Flag for adaption polynomial ADAPT / adaptation function EADAPT Like in Parent Profile (Sub Profile option only) Expression =0: =0: Not used and not evaluated =1: Correction for kA [KA = KAN char lines factor * polynomial] =2: Calculation of kA [KA = KAN polynomial] =1000: Not used, but ADAPT evaluated as RADAPT (Reduction of the computing time) =-1: Correction for kA [KA = KAN char lines factor * adaptation function] =-2: Calculation of kA [KA = KAN adaptation function] =-1000: Not used, but EADAPT evaluated as RADAPT (Reduction of the computing time)
EADAPT	Adaptation function
KAN	K*A (nominal)
M1N	Primary mass flow (nominal)
M3N	Secondary mass flow (nominal)
QN	Heat-exchanger power (nominal)=Q34N
V1N	Specific volume for primary side inlet 1 (nominal)
V3N	Specific volume for secondary side inlet 3 (nominal)

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

The following table shows, whether KAN or DT3S2N is to be used, or whether T2 or M2 are to be calculated or specified as defaults respectively:

	GLOBAL = Design		GLOBAL = Off-design
	FMODE = Design	FMODE = Off-design (local) =1,2	FMODE = Design	FMODE = Off-design (local) =1,2
KAN	optional value	specified by the user	specified by the user	specified by the user
DT3S2N	specified by the user	optional value	optional value	optional value

	GLOBAL = Design and FMODE = Design	GLOBAL = Off-design or FMODE = Off-design
	FSPEC without meaning	FSPEC
	FSPEC without meaning	=0	=1	=2
T2	is calculated	is calculated	Definition necessary	is calculated
M2	is calculated	Definition through M1N	is calculated	definition optional

Characteristic lines

1. Characteristic line FK1 = f (M1/M1N)

2. Characteristic line FK2 = f (M3/M3N)

(K*A)/(K*A)N = FK1 * FK2

Characteristic line 1: (k*A)-characteristic line: (k*A)1/(k*A)N = f (M1/M1N)

     X-axis        1         M1/M1N                     1. point
                        2          M1/M1N                     2. point
                        .
                      N         M1/M1N                     last point

     Y-axis        1          (k*A)1/(k*A)N            1. point
                        2          (k*A)1/(k*A)N            2. point
                        .
                        N         (k*A)1/(k*A)N            last point

Characteristic line 2: (k*A)-characteristic line: (k*A)2/(k*A)N = f (M3/M3N)

     X-axis        1          M3/M3N                     1. point
                        2          M3/M3N                     2. point
                        .
                        N         M3/M3N                     last point

     Y-axis        1          (k*A)2/(k*A)N            1. point
                        2          (k*A)2/(k*A)N            2. point
                        .
                        N         (k*A)2/(k*A)N            last point

Physics used

Equations

All cases

if FDP12RN=relative, then {DP12N=P1*DP12RN}

else {DP12N=DP12RN}

if FDP34RN=relative, then {DP34N=P3*DP34RN}

else {DP34N=DP34RN}

Design case

(Simulation flag:

GLOBAL = Design case

AND

FMODE = GLOBAL)

P4 = P3 - DP3N                                          (2)
P5 = P3                                                         (3)
T4S = fsat(P4)
T4 = T4S
H4 = fsat(P4)                                               (5)
M4 = M3 + M5                                            (8)
Q4 = M4 * H4
DQ = (Q3 + Q5 - Q4)*(1-DQLR)

P2 = P1 - DP12N                                        (1)
Q2 = Q1 + DQ
M2 = M1                                                      (7)

if FSPEC = 0, 1, 2, , then {T2 = T3S - DT3S2N

H2=f(P2,T2,X=0)

M1=M2=Q2/H2 }

if FSPEC = 5, 15, 25 , then {H2=f(P2,T2,X=0)

M1=M2=Q2/H2 }

DTL = T4 - T1
DTU = T3 - T2

LMTD = (DTU - DTL)/(ln(DTU) - ln(DTL))

KAN = DQ/LMTD
KAN = M1*H1 + M2*H2 (6v)

if FSPEC = 1 , then {

M2 = DQ/(H2 - H1) } (9)

Off-design case

(Simulation flag:

GLOBAL = Off-design

FMODE = local off-design)

F1 = (M1/M1N) ** 2

if GLOBAL = design, then F1 = 1.0

P2 = P1 - DP12N * F1 (1)
M2 = M1 (7)

if GLOBAL = design, then {
Fk1=1.0
Fk2=1.0 }

if local (FMODE) = off-design, then {
        Fk1   = f (M1/M1N) from characteristic line 1
        Fk2   = f (M3/M3N) from characteristic line 2 }

KA = KAN * Fk1 * Fk2
F3 = (M3/M3N) ** 2
M4 = M3 + M5                                            (8)

P3 = P4 + DP34N * F3 (2,4tb)
P5 = P3 (3)

Start of the iteration

T4 = fsat(P4)
H4 = fsat(P4) (5)
Q12 = (Q3 + Q5 - M4*H4) * (1-DQLR)

if FSPEC = 0,2 , then {

H2 = H1 + Q12/M2
T2 = f(P2,H2) }

if FSPEC = 1 , then { T2 from input }

DTL = T4 - T1
DTU = T3 - T2
LMTD = (DTU - DTL)/(ln(DTU) - ln(DTL))

QQ = KA * LMTD
DQQ = Q12 - QQ

Start of the regula falsi method
grad = (P4- P4old)/(DQQ - DQQold)
P4 = P4 - DQQ * grad (4ta)
End of the regula falsi method

DQ = | DQQ/((Q12+QQ)*.5) |

if DQ < TOL then end the iteration
else continue the iteration

if FSPEC = 0, 5 , then {

M2 = M1 = M1N } (9a)

if FSPEC = 1, 15 , then {

M2 = Q12/(H2 - H1) } (9b)

if FSPEC = 2, 25 , then {

M2 = M1 from boundary value }

Variable connection table

Eq.-No.		Line
		1	2	3	4	5
1	P	X	X
2	P			X	(X)
3	P			X		(X)
4(t)	P			(X)
	H	X	X	X	X	X
	M	X	X	X	X	X
5	H				(X)
6(v)	H	X	X
	M	X	X
7	M	X	X
8	M			X	X	X
9	M		(X)

Note: Footnotes have the following meaning

t for off-design, and

v for design.

Example

Click here >> Component 67 Demo << to load an example.

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