1 TEMA PROIECTULUI

Sa se proiecteze un cazan intr-o instalatie de incalzire centrala cu apa calda avand urmatoarele caracteristici:

Date de proiectare: Numarul de ordine n= 24

Temp. de tur a apei t tur = 85 CTemp. de retur a apei t retur = 65 C 814.1

Sarcina termica sau Q u = 0.7 G cal/h sau 814.1 kW sau kJ/sCoeficient exces = 1.05

Combustibil gazos

1.1 Calculul arderii combustibilului

c 83.2 % 0.832

h 3.6 % 0.036o 0.6 % 0.006 L =

s 2.9 % 0.029w 6.3 % 0.063 Vg =a 3.4 % 0.034

1.55404 1.55404 16.99563 0.16995634

0.48190 0.48190 5.27028 0.05270281

0.02031 0.02031 0.22215 0.00222148

0.08859 0.08859 0.96890 0.00968899

6.99890 6.99890 76.54304 0.765430389.14374 9.14374 100.00000 1.00

1.2 Diagrama entalpie-temperatura

1.3 Puterea calorifica inferioara a combustibilului32532.2075 kJ/m3 comb

1.4 Pierderile specifice de caldura ale cazanului165 C 2104.976295843 kJ/m3 CB

0.06470 6.47%0.01 1.0%

0 0%0.05285 5.28%

0 0%

1.5 Randamentul termic al cazanului = 0.87245 = 87.25%

1.6 Calculul consumului de combustibilB = 0.0284506466 kg/s sau B = 102.422327922 kg/h

pentru: 20 C1.79 kJ/kgK

1.29720 C

1.7 Bilantul termic general al cazanului

O min =

L min =

Vg min =

V co2 = m3N/kg comb r co2 =

V H2O = m3N/kg comb r H2O =

V so2 = m3N/kg comb r so2 =

V o2 = m3N/kg comb r o2 =

V N2 = m3N/kg comb r N2 = V i = r i =

V i =Vg

PCI =

t g cos = I g cos =

q2 =q3 =q4 =q5 =q6 =

tc =cc =

cpL = kJ/m3N KtL =

2925.5623401675 kW1.0185331499 kW6.5382994218 kW

933.1191727393 kW814.1 kW

59.8879367893 kW9.2556234017 kW

0 kW48.9117399932 kW

0 kW118.0553001842 kW 814.1932.1553001842 kW

eroarea de inchidere a bilantului termic = 0.0010334914 = 0.10%

3 = 12.07

* caz C cu trei drumuri convectiveo Bilantul termic al primului drum convectiv

160.9845234418 kW0.5 50%

8235.6027959974 kJ/kg CB607.78 C

o Bilantul termic al celui de-al doilea drum convectiv

96.5907140651 kW0.3 30%

4651.1540407999 kJ/kg CB355.3695592149 C

o Bilantul termic al celui de-al treilea drum convectiv

64.39 kW

2261.5215373349 kJ/kg CB177.0740018243 C

= 12.07

a) Calculul aproximativ al focarului

492130.95 [W] 492130.950.70 0.705.66950 5.669501273.15 [K] 1273.15100.00 100.00373.15 [K] 373.154.75484 3.98864

b) Redimensionarea geometrica a focarului

0.108 [m] 0.1080.85 [m] 0.850.70 [m] 0.701.05 [m] 1.050.56 [m] 0.560.28 [m] 0.280.50 [m] 0.503 31.58533 [m] 1.3664115.67895 16 13.651961.62000 [m] 1.404004.87620 4.120207.14000 6.38400

= 0.68294 = 0.645391.19070 1.03194

s= 0.60035 [m] s= 0.58192

c) Calculul exact al focarului

0.9 0.9

QC I - fluxul termic schimbat in primul drum convectivQC I =

Aleg n I =Ic I - entalpia gazelor de ardere la iesirea din primul drum convectivIc I =tc I =

QC II - fluxul termic schimbat in al doilea drum convectivQC II =

Aleg n II =Ic II - entalpia gazelor de ardere la iesirea din al doilea drum convectivIc II =tc II =

QC III - fluxul termic schimbat in al treilea drum convectivQC III =IC III - entalpia gazelor de ardere la iesirea din al treilea drum convectivIC III =tC III =

QR= QR== =C0= [W/m2K4] C0=Tf= Tf=

tper= tper=Tper= Tper=SRap= [m2] SRap=

dTV= dTV=df= df=af= af=hf= hf=

hsam= hsam=harz= harz=lsam= lsam=

nelisp= nelisp=lf= lf=

nel= nel=lf= lf=

SR= [m2] SR=Sper= [m2] Sper=

Vf= [m3] Vf=

= =

42382.02 [K] 2382.020.55 0.55

p= 1.013 [bar] p= 1.013s= 0.60035 [m] s= 0.58192

1.05 1.0523.11111 23.111110.172166 [bar] 0.1700 0.1721660.053388 [bar] 0.0527 0.0533880.002250 [bar] 0.0022215 0.002250

kg= 0.26611 kg= 0.27047kf= 1.0123970 kf= 1.0123970

0.2666667 0.2666667M= 0.4667 M= 0.4667

0.54046 0.530570.14942 0.147380.36449 0.358130.45647 0.463673.98864 3.92668

d) Eroarea de calcul

17.53 1.57

Sistemul convectiv

0.172166 [bar] 0.169960.053388 [bar] 0.052700.002250 [bar] 0.0022215

p= 1.0132 drumuri convective

Qc1= 209279.88Primul drum convectiv Vg= 9.1437

B= 0.028451000483.638565634.79741.811014.96373.150.95

m= 0.0040.086380.00012034

Pr= 0.6058Prp= 0.6700

1005.66950.82

kg= 0.801640.075900.108

s= 0.0972w= 9

0.10740lconv1=af= 0.70

drum convectiv in deasupra 0.2894rotunjit 0.27

0.09590vit reala w= 10.08

Re= 9045.91Cs= 1.000

Iteratie 1 Cn= 0.975

T0= T0== =

= == =

pCO2= rCO2= pCO2=pH2O= rH2O= pH2O=pSO2= rSO2= pSO2=

hrel= hrel=

fl 1= fl 1=fl 2= fl 2=fl= fl=f= f=

SRex= [m2] SRex=

= =

pCO2= rCO2=pH2O= rH2O=pSO2= rSO2=

tg'=tf=tg"=tcI=

ttur=tretur=tmed=tmg=Tmg=Tper=

=

==

tper=C0=P=

g=dech=

Str=

hconv1=hconv1=

Str=

5nr el= 21n= 20

Nu= 78.146926522762.50286.298065.6757

k= 52.01206.33866.918.65 %

deci lconv1= 0.700.27

C=R=1=

StC=SgC=

eroarea =

hconv1=

6

7cgcgmg-6sspppercc-2 2R004ppggR11ctctccggg11tr tr cgcgtr tr cgg mgcgcgtr cg

8TEMA PROIECTULUI

Qu= 814.1 kW0.8141 MW

1.77187 1.77187

8.43749 8.437498.85937 L = 8.8593669792

8.72187 8.72186998619.14374 Vg = 9.1437446042

1.013 bar

0.17217 bar

0.05339 bar

0.00225 bar

0.00981 bar

0.77538 bar1.01300

Diagrama entalpie-temperatura

Puterea calorifica inferioara a combustibilului

Pierderile specifice de caldura ale cazanului

Randamentul termic al cazanului

Calculul consumului de combustibil

Bilantul termic general al cazanului

m3N/kg comb O min = m3N/kg comb

m3N/kg comb L min = m3N/kg combm3N/kg comb m3N/kg comb

m3N/kg comb Vg min = m3N/kg combm3N/kg comb m3N/kg comb

pB =

p co2 =

p H2O =

p so2 =

p o2 =

p N2 = p i =

p i =p bar

9Bilanturile termica partiale alea suprafetelor de transfer termic

10

[W]

[K]

[K]3.92668

[m] 0.108 [m][m] 0.85 [m][m] 0.70 [m][m] 1.05 [m][m] 0.56 [m][m] 0.28 [m][m] 0.50 [m]

3[m] 1.34871 [m]

14 13.48804[m] 1.30 [m]

13

[m]

[W/m2K4]

[m2] SRex= [m2]

dTV=df=af=hf=

hsam=harz=lsam=

nelisp=lf=

nel=lf=

[m2] nel=[m2]

[m3]

11

[K]

[bar][m]

[bar] 0.1700[bar] 0.0527[bar] 0.0022215

0.172166 [bar] 0.169960.053388 [bar] 0.052700.002250 [bar] 0.0022215

p= 1.0132 drumuri convective

Qc2= 112689.17Al 2-lea drum convectiv Vg= 9.1437

B= 0.02845483.63165.08565215.95324.31597.46373.150.95

m= 0.0040.050490.00004935

Pr= 0.6476Prp= 0.6700

1005.66950.82

kg= 0.999940.093770.108

s= 0.0972w= 9

0.063221.32

drum convectiv lateral 0.1341rotunjit 0.18

0.17453vit reala w= 3.26

Re= 7135.09Cs= 1.000Cn= 0.975

rCO2=rH2O=rSO2=

[m2]

pCO2= rCO2=pH2O= rH2O=pSO2= rSO2=

tg'=tcI=tg"=tgcos=

ttur=tretur=tmed=tmg=Tmg=Tper=

=

==

tper=C0=P=

g=dech=

Str=hconv2=hf+hconv1=

lconv2=lconv2=

Str=

12

nr el= 21n= 20

Nu= 69.616910232.54660.000030.9192

k= 27.516118.964521.3811.95 %

deci lconv2= 0.181.32

C=R=1=

StC=SgC=

eroarea =

hconv2=

13

14

Nr.crt Temp

1 0 0 0 0 0 0 0 0 0 02 100 170.04 264.25 150.54 72.55 181.38 3.68 131.78 11.67 130.033 200 357.52 555.60 304.48 146.73 377.70 7.67 267.11 23.66 260.774 300 558.89 868.54 462.70 222.98 587.28 11.93 406.84 36.04 393.205 400 771.84 1199.47 626.13 301.73 806.94 16.39 551.04 48.82 528.246 500 994.29 1545.16 794.82 383.02 1034.84 21.02 698.98 61.93 666.287 600 1224.81 1903.40 968.90 466.91 1267.59 25.75 850.27 75.33 807.138 700 1462.03 2272.05 1148.97 553.69 1506.31 30.60 1004.01 88.95 950.979 800 1704.69 2649.15 1334.66 643.17 1746.91 35.48 1159.99 102.77 1097.3910 900 1951.99 3033.47 1526.10 735.43 1992.18 40.47 1318.01 116.77 1246.2711 1000 2204.16 3425.35 1722.98 830.31 2237.80 45.46 1477.56 130.90 1397.0312 1100 2458.20 3820.13 1925.85 928.07 2486.21 50.50 1636.35 144.97 1549.6613 1200 2715.98 4220.73 2132.30 1027.56 2734.67 55.55 1800.71 159.53 1703.9414 1300 2977.51 4627.16 2344.25 1129.70 2994.11 60.82 1963.19 173.93 1859.9115 1400 3239.00 5033.53 2559.07 1233.22 3245.35 65.92 2127.60 188.49 2017.3616 1500 3502.41 5442.88 2779.51 1339.45 3496.77 71.03 2293.83 203.22 2174.2717 1600 3769.52 5857.97 3001.78 1446.56 3750.80 76.19 2460.11 217.95 2334.9318 1700 4036.63 6273.07 3229.68 1556.39 4004.34 81.34 2628.18 232.84 2493.7119 1800 4303.61 6687.97 3459.45 1667.11 4260.04 86.53 2798.16 247.90 2654.3220 1900 4574.60 7109.10 3691.04 1778.72 4510.87 91.63 2969.15 263.05 2814.9821 2000 4843.58 7527.10 3926.43 1892.15 4770.68 96.91 3138.13 278.02 2977.5122

1.55403733 0.481901 0.020313 0.088594

Ico2 IH20 ISO2 Io2 INkJ/m3N kJ/m3N kJ/m3N kJ/m3N kJ/m3N

Volum gaze de ardere

V co2 V H2O V so2 V o2 V N2

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I g k

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IgkJ/kg CB

0 0.00910.07 1262.22

1825.10 2558.772751.97 3891.453697.10 5263.514663.23 6674.365649.02 8120.416655.74 9601.037680.52 11111.108722.52 12648.659777.67 14209.68

### 15789.59### 17389.08### 19008.93### 20640.46### 22274.07### 23940.62### 25596.87### 27266.84### 28944.25### 30633.47

6.9989

IN2kJ/m3N

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Parametrii gazelor rezultate ale arderii

Nr crt.Temp Gaze de ardere

lamda miu Pr

1 0 2.28 12.20 0.722 100 3.13 21.50 0.693 200 4.01 32.80 0.674 300 4.84 45.80 0.655 400 5.70 60.40 0.646 500 6.56 76.30 0.637 600 7.42 93.60 0.628 700 8.27 112.10 0.619 800 9.15 131.80 0.60

10 900 10.01 152.50 0.5911 1000 10.90 174.30 0.58

o C 102 W/mK 106 m2/s

mersul lucrariicalcul diagrama entalpie-tempParametrii gazelor de ardere