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Tehnička termodinamika - Kemijsko-tehnološki fakultet

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TEHNIČKA TERMODINAMIKA__________________________________________<br />

d)<br />

w k = w 2 + w<br />

,3<br />

3,1<br />

w<br />

2,3<br />

= u2<br />

− u3<br />

= . 16<br />

2495 − u<br />

2<br />

−1<br />

u3 = h3<br />

− p3<br />

⋅ v3<br />

= 2467.23 − 0.2 ⋅10<br />

⋅ 7.2088 = 2323.05 kJ kg<br />

−1<br />

w2,3<br />

= u2<br />

− u3<br />

= 2495.16 − 2323.05 = 172.106 kJ kg<br />

2<br />

−1<br />

( v − ) = 0.2 ⋅10<br />

⋅ ( 2.3014 − 7.2088) = −98.15 kJ<br />

w 3,1<br />

= p ⋅ 1 v3<br />

kg<br />

3<br />

w k<br />

−1<br />

= 172.106 − 98.15 = 73.956 kJ kg<br />

e)<br />

Slika P5.14.e<br />

Primjer 5.15.<br />

3<br />

Mokra para koju sačinjava 5.8 dm vrele vode i 10 kg suhe pare na tlaku<br />

15.7 bar zagrijava se pri konstantnom tlaku dok ne postigne temperaturu 300 °C.<br />

Ovako pregrijana para ekspandira adijabatski na 0.196 bar.<br />

a) Izračunaj ukupnu količinu dovedene topline.<br />

b) Izračunaj izvršeni rad.<br />

c) Skiciraj proces u p, v – i T, s – dijagramu.<br />

260

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