Issue 15

N. Zuli

ani, Frattura ed

Integrità Struttu

rale, 15 (2011)

29-34; DOI: 10 reformate Mean cell pow density [mW/cm 2 ]

.3221/IGF-ESIS.1

5.04

hydrogen Mean cell pow density [mW/cm 2 ]

er

Stac pow [W

k er ]

er

Stac pow [W

k er ]

Current densit [mA/cm 2 ]

y

Me volt

an cell age [V]

Me volt

an cell age [V]

200 400 580 Table 1 : P

0 0 0

.63 .56 .50

126 223 292

157 279 36

0 0

.60 .51 -

119 204 -

14 25 -

9 5

5 stack operatin o the stack t 4 based fuel stack. uels containi e first stack uel and low r to obtain b

erformance d ribution follo re dependen lated to the d -uniformity y associated ue to the co uels stack tem

ifferences at 2 ws a parabo t performanc ifferent reac becomes eve to cell tempe mbined effe perature dis

00 and 400 mA lic pattern th e of the sing tant distribut n more notic rature [17]. I ct of CO con tribution is c

/cm 2 for the at is similar t le PBI/H 3 PO ion along the eable when f n this case th tent in the f rucial in orde

g with hydrog emperature p cell. Voltage ng CO are us cell (see red cell temperat est performa

en and reform rofile (see Fi differences b ed. In fact th arrow in Fig ure. In the c nce.

ate as fuel. g. 8). This is etween adja e CO poison . 6) presents ase of opera

Th to t cell Th effe low wit

e voltage dist he temperatu s could be re e voltage non ct is strongl est voltage d h reformate f

due cent ing the ting

S T F tem nam

ACK TEMPE

RATURE DI

STRIBUTION

tack een this tack r at the

ig. 7 and mean te central a perature beh ed T1, T2 a stack middl hode air cool

Fig. 8 show mperature an nd end sta aviour. It is nd T3 (Fig. 7 e reaching 2 ing effect. In

the temper d 400 mA/ ck parts (ab also possibl and Fig. 9). 5°C between fact, reactan

ature distribu cm 2 current out 20°C). e to observe T1 temperat T1 and T2 t air enters th

tion along th density load The heat di the temper ure is the low . This tempe e stack from

e stack ope . There is a spersion thr ature differen est compare rature behav the T1 sectio

rating with p marked tem ough the en ces amongs d to T3 and iour could b n and leave

ure hydrogen perature dif d plates co t the 3 secti T2. Differen e explained from the T3

at 160°C s ference betw uld explain ons of the s ces are highe referring to (Fig. 9).

the cat

100 120 140 160 180 200

°C

T1 T2 T3

60 80

50

100

150

200

0

mm

Figure 7 : Th urrent density

ermal image o 400 mA/cm 2 fuel: pur

f the 25 cells , mean stack te e hydrogen.

HTPEM stack mperature 16

. 0°C,

Figure 8 : Sta 400 mA/

ck temperatur cm 2 , mean sta fuel: pure h

e profile. Curr ck temperature ydrogen.

ent density 160 °C,

C

F

igure 9 : Simpl

ification schem

e of the air p

ath through th

e fuel cell stac

k.

33