integration of solid oxide fuel cells and ... - Ea Energianalyse

5. SIMULATION AND RESULTS
these are only included in the figure with the electrical efficiency (figure
5.27A). The components in the ABS system generally only affect the cooling
power so these are only included in the figure with the COP (figure
5.27B).
ηsys,el,net increase
SOFC system Pressure Losses: El. efficiency
5%
4%
3%
2%
1%
0%
∆pBurn,i,2
∆pGGHEX3,c
∆pGGHEX3,h
∆pGGHEX4,c
∆pGGHEX4,h
∆pMIXG2,i,1
∆pSPG2,o,1
∆pWGHEX1,g
∆pWGHEX2,g
∆pWGHEX3,g
-50% -30% -10% 10% 30% 50%
-1%
-2%
-3%
-4%
-5%
Increase of ∆p (relative to std parameter cfg.)
COPABS,fuel increase
ABS unit Pressure Losses: COP
5%
4%
3%
2%
1%
0%
-10% -5% 0% 5% 10%
-1%
-2%
-3%
-4%
-5%
Increase of ∆p compared to absolute pressure
∆pABSO,r
∆pABSO,s
∆pCOND1,r
∆pCOND2,r
∆pDES1
∆pSHEX1,ss
∆pDES2
∆pSHEX1,ws
∆pEVAP,r
∆pMIXL1,1
∆pMIXL1,2
∆pMIXR1,1
∆pMIXR1,2
∆pSHEX2,ss
∆pSHEX2,ws
Figure 5.27: A Note that the left figure shows the components of the SOFC system and exhaust
gas. These components have a pressure losses to begin with, so the x-axis shows the percentage
increase of this value. B The right figures shows the components of the ABS system. They do not
have a pressure loss to begin with (it is zero as standard). So for these the percentage increase of
the loss (x-axis) is of the absolute pressure in the given component.
η sys,el ,net
The pressure losses in the SOFC system have been approximated to
values from the TOFC models, so they are assumed to be relatively
reliable, and hence they are assumed to lay within +/- 50% of the
standard parameter value.
It can be seen that all the pressure losses are relatively insignificant
- the most influential is the Burner and GGHEX3, which can change the
electrical efficiency one percent (0,5 percent point), see figure 5.27A. The
reason why these have a bigger influence than the other pressure losses
is, that the standard loss is 4kPa in both of these (while the pressure
loss is smaller for each of the other components) which means that if
144