results and sample of calculation
TRANSCRIPT
1.0 RESULTS AND SAMPLE OF CALCULATION
7.1 Results
Experiment
Reading
No ProcessSensible Heating Steam
Humidification
Cooling and
Dehumidification
1 kW 1.5 kW 1 kW 1.5 kW
T1 (TA d) 26.9 26.8 27.3 27.9 29.1 29.5
T2 (TA w) 22.2 22.2 22.6 23.4 23.5 23.4
T3 (TB d) 27.0 35.8 36.9 31.4 29.6 29.7
T4 (TB w) 23.0 26.5 27.3 31.2 24.6 24.5
T5 (TC d) 23.7 32.2 36.2 30.8 18.2 18.2
T6 (TC w) 22.4 24.7 25.4 30.6 17.6 17.4
T7 (TD d) 23.7 31.1 38.9 30.9 18.8 18.6
T8 (TD w) 22.5 24.4 26.2 30.7 18.2 18.0
T9 (T 1) X X X 10.7 11.1
T10 (T 2) X X X 71.4 78.5
T11 (T 3) X X X 44.9 45.2
T12 (T 4) X X X 6.3 6.6
Qp (W) X 1009.7 1009.7 X X
Qr (W) X 0 536.9 X X
Qb (W) X X 2742.9 X
Pevap (P 1) (kN/m2) X X X 209.0 211.7
Pcond (P 3) (kN/m2) X X X 1121.8 1134.0
ma (g/s) 103.2 99.9 99.4 100.7 100.8 103.7
mr (g/s) X X X 12.3 12.1
Time (s) X X X X 486
Drain Water (ml) X X X 100 ml
Table 7.1.1 : Results
7.2 Sample of Calculation:
Test 1 : No Process
ma=103.2 g/ [email protected] /s
Inlet Outlet
T dry=26.9℃ T dry=23.7℃
T wet=22.2℃ T wet=22.5℃
∅ i=76 % ∅ o=86 %
w i=15.5 x10−3kgH 2O/kgair wo=16.5 x10−3 kgH2O /kgair
Temperature drops at exit
∆T dry :26.9−23.7=3.2℃
Temperature rises at exit
∆T wet :22.5−22.2=0.3℃
Test 2 : Sensible Heating
1kW preheat
ma=99.9g /[email protected] kg/ s
Inlet Outlet
T dry=26.8℃ T dry=31.1℃
T wet=22.2℃ T wet=24.4℃
∅ i=67 % ∅ o=59 %
w i=15 x10−3kgH 2O/kgair wo=16.75 x10−3 kgH2O /kgair
Temperature rises at exit
∆T dry :31.1−26.8=4.3℃
∆T wet :24.4−22.2=2.2℃
1.5kW preheat
ma=99.9g /[email protected] kg/ s
Inlet Outlet
T dry=27.3℃ T dry=38.9℃
T wet=22.6℃ T wet=26.2℃
∅ i=68 % ∅ o=36 %
w i=15.25 x10−3 kgH 2O/kgair wo=15.75 x10−3 kgH2O /kgair
Temperature rises at exit
∆T dry :38.9−27.3=11.6℃
∆T wet :26.2−22.6=3.6℃
Test 3 : Steam Humidification
ma=100.7 g /[email protected] kg/ s
Inlet Outlet
T dry=27.9℃ T dry=30.9℃
T wet=23.4℃ T wet=30.7℃
∅ i=68% ∅ o=100%
w i=16.25 x10−3 kgH 2O/kgair wo=29 x10−3 kgH 2O /kgair
Temperature rises at exit
∆T dry :30.9−27.9=3℃
∆T wet :30.7−23.4=7.3℃
Dry air mass balance
ma1=ma2
=ma
∆ w=w2−w1
¿ (29 x10−3 )−(16.25 x10−3 )
¿12.75 x10−3kgH 2O/kgair
Water mass balance
ma2w2=ma1
w1+mw
mw=ma2w2−ma1
w1
¿ ma(w2−w1)
¿0.1007(12.75x 10−3)
¿1.2839 x10−3 kg /s
The relative humidity changes
∆∅=∅ o−∅ i
¿100 %−68 %
¿32%@0.32
Test 4 : Cooling and Dehumidification
ma=100.8 g/ [email protected] kg /s
Inlet Outlet
T dry=29.1℃ T dry=18.8℃
T wet=23.5℃ T wet=18.2℃
∅ i=63 % ∅ o=100%
w i=16 x10−3 kgH2O /kgair wo=13.75 x10−3 kgH2O /kgair
hi=70 kJ /kgair ho=54kJ /kgair
Temperature drops at exit
∆T dry :29.1−18.8=10.3℃
∆T wet :23.5−18.2=5.3℃
∆ w=w1−w2
¿ (16 x10−3 )−(13.75 x 10−3 )
¿2.25 x10−3kgH 2O/kgair
Water mass balance
ma1w1=ma2
w2+mw
mw=ma1w1−ma2
w2
¿ ma(w2−w1)
¿0.1008(2.25 x 10−3)
¿0.2268 x10−3kg /s
The relative humidity changes
∆∅=∅ o−∅ i
¿100 %−63 %
¿37%@0.37
Assumption:
T w=18.8℃
T h
15 62.982
18.8 hw
20 83.915
18.8−1520−15
=hw−62.982
83.815−62.982
hw=78.81508 kJ /kg
Energy balance
E¿=Eout
ma1h1=mw hw+ma2
h2+ Qout
Qout=ma (h1−h2 )−mwhw
¿0.1008 (70−54 )−0.0002(78.81508)
¿1.629kW
ma=103.7 g /[email protected] kg/ s
Inlet Outlet
T dry=29.5℃ T dry=18.6℃
T wet=23.4℃ T wet=18.0℃
∅ i=60% ∅ o=95%
w i=15.75 x10−3 kgH 2O/kgair wo=12.75 x10−3 kgH2O /kgair
hi=70kJ /kgair ho=51kJ /kgair
Temperature drops at exit
∆T dry :29.5−18.6=10.9℃
∆T wet :23.4−18.0=5.4℃
∆ w=w1−w2
¿ (15.75 x10−3 )−(12.75 x10−3 )
¿3 x10−3kgH 2O/kgair
Water mass balance
ma1w1=ma2
w2+mw
mw=ma1w1−ma2
w2
¿ ma(w2−w1)
¿0.1037(3x 10−3)
¿0.3111x 10−3 kg /s
The relative humidity changes
∆∅=∅ o−∅ i
¿95%−60 %
¿35 %@0.35
Assumption:
T w=18.6℃
T h
15 62.982
18.6 hw
20 83.915
18.6−1520−15
=hw−62.982
83.815−62.982
hw=77.98176 kJ /kg
Energy balance
E¿=Eout
ma1h1=mw hw+ma2
h2+ Qout
Qout=ma (h1−h2 )−mwhw
¿0.1037 (70−51 )−0.0003(77.98176)
¿1.947 kW
2.0 RESULTS AND SAMPLE OF CALCULATION
7.1 Results
Experiment
Reading
No ProcessSensible Heating Steam
Humidification
Cooling and
Dehumidification
1 kW 1.5 kW 1 kW 1.5 kW
T1 (TA d) 26.9 26.8 27.3 27.9 29.1 29.5
T2 (TA w) 22.2 22.2 22.6 23.4 23.5 23.4
T3 (TB d) 27.0 35.8 36.9 31.4 29.6 29.7
T4 (TB w) 23.0 26.5 27.3 31.2 24.6 24.5
T5 (TC d) 23.7 32.2 36.2 30.8 18.2 18.2
T6 (TC w) 22.4 24.7 25.4 30.6 17.6 17.4
T7 (TD d) 23.7 31.1 38.9 30.9 18.8 18.6
T8 (TD w) 22.5 24.4 26.2 30.7 18.2 18.0
T9 (T 1) X X X 10.7 11.1
T10 (T 2) X X X 71.4 78.5
T11 (T 3) X X X 44.9 45.2
T12 (T 4) X X X 6.3 6.6
Qp (W) X 1009.7 1009.7 X X
Qr (W) X 0 536.9 X X
Qb (W) X X 2742.9 X
Pevap (P 1) (kN/m2) X X X 209.0 211.7
Pcond (P 3) (kN/m2) X X X 1121.8 1134.0
ma (g/s) 103.2 99.9 99.4 100.7 100.8 103.7
mr (g/s) X X X 12.3 12.1
Time (s) X X X X 486
Drain Water (ml) X X X 100 ml
Table 7.1.1 : Results
7.2 Sample of Calculation:
Test 1 : No Process
ma=103.2 g/ [email protected] /s
Inlet Outlet
T dry=26.9℃ T dry=23.7℃
T wet=22.2℃ T wet=22.5℃
∅ i=76 % ∅ o=86 %
w i=15.5 x10−3kgH 2O/kgair wo=16.5 x10−3 kgH2O /kgair
Temperature drops at exit
∆T dry :26.9−23.7=3.2℃
Temperature rises at exit
∆T wet :22.5−22.2=0.3℃
Test 2 : Sensible Heating
1kW preheat
ma=99.9g /[email protected] kg/ s
Inlet Outlet
T dry=26.8℃ T dry=31.1℃
T wet=22.2℃ T wet=24.4℃
∅ i=67 % ∅ o=59 %
w i=15 x10−3kgH 2O/kgair wo=16.75 x10−3 kgH2O /kgair
Temperature rises at exit
∆T dry :31.1−26.8=4.3℃
∆T wet :24.4−22.2=2.2℃
1.5kW preheat
ma=99.9g /[email protected] kg/ s
Inlet Outlet
T dry=27.3℃ T dry=38.9℃
T wet=22.6℃ T wet=26.2℃
∅ i=68 % ∅ o=36 %
w i=15.25 x10−3 kgH 2O/kgair wo=15.75 x10−3 kgH2O /kgair
Temperature rises at exit
∆T dry :38.9−27.3=11.6℃
∆T wet :26.2−22.6=3.6℃
Test 3 : Steam Humidification
ma=100.7 g /[email protected] kg/ s
Inlet Outlet
T dry=27.9℃ T dry=30.9℃
T wet=23.4℃ T wet=30.7℃
∅ i=68% ∅ o=100%
w i=16.25 x10−3 kgH 2O/kgair wo=29 x10−3 kgH 2O /kgair
Temperature rises at exit
∆T dry :30.9−27.9=3℃
∆T wet :30.7−23.4=7.3℃
Dry air mass balance
ma1=ma2
=ma
∆ w=w2−w1
¿ (29 x10−3 )−(16.25 x10−3 )
¿12.75 x10−3kgH 2O/kgair
Water mass balance
ma2w2=ma1
w1+mw
mw=ma2w2−ma1
w1
¿ ma(w2−w1)
¿0.1007(12.75x 10−3)
¿1.2839 x10−3 kg /s
The relative humidity changes
∆∅=∅ o−∅ i
¿100 %−68 %
¿32%@0.32
Test 4 : Cooling and Dehumidification
ma=100.8 g/ [email protected] kg /s
Inlet Outlet
T dry=29.1℃ T dry=18.8℃
T wet=23.5℃ T wet=18.2℃
∅ i=63 % ∅ o=100%
w i=16 x10−3 kgH2O /kgair wo=13.75 x10−3 kgH2O /kgair
hi=70 kJ /kgair ho=54kJ /kgair
Temperature drops at exit
∆T dry :29.1−18.8=10.3℃
∆T wet :23.5−18.2=5.3℃
∆ w=w1−w2
¿ (16 x10−3 )−(13.75 x 10−3 )
¿2.25 x10−3kgH 2O/kgair
Water mass balance
ma1w1=ma2
w2+mw
mw=ma1w1−ma2
w2
¿ ma(w2−w1)
¿0.1008(2.25 x 10−3)
¿0.2268 x10−3kg /s
The relative humidity changes
∆∅=∅ o−∅ i
¿100 %−63 %
¿37%@0.37
Assumption:
T w=18.8℃
T h
15 62.982
18.8 hw
20 83.915
18.8−1520−15
=hw−62.982
83.815−62.982
hw=78.81508 kJ /kg
Energy balance
E¿=Eout
ma1h1=mw hw+ma2
h2+ Qout
Qout=ma (h1−h2 )−mwhw
¿0.1008 (70−54 )−0.0002(78.81508)
¿1.629kW
ma=103.7 g /[email protected] kg/ s
Inlet Outlet
T dry=29.5℃ T dry=18.6℃
T wet=23.4℃ T wet=18.0℃
∅ i=60% ∅ o=95%
w i=15.75 x10−3 kgH 2O/kgair wo=12.75 x10−3 kgH2O /kgair
hi=70kJ /kgair ho=51kJ /kgair
Temperature drops at exit
∆T dry :29.5−18.6=10.9℃
∆T wet :23.4−18.0=5.4℃
∆ w=w1−w2
¿ (15.75 x10−3 )−(12.75 x10−3 )
¿3 x10−3kgH 2O/kgair
Water mass balance
ma1w1=ma2
w2+mw
mw=ma1w1−ma2
w2
¿ ma(w2−w1)
¿0.1037(3x 10−3)
¿0.3111x 10−3 kg /s
The relative humidity changes
∆∅=∅ o−∅ i
¿95%−60 %
¿35 %@0.35
Assumption:
T w=18.6℃
T h
15 62.982
18.6 hw
20 83.915
18.6−1520−15
=hw−62.982
83.815−62.982
hw=77.98176 kJ /kg
Energy balance
E¿=Eout
ma1h1=mw hw+ma2
h2+ Qout
Qout=ma (h1−h2 )−mwhw
¿0.1037 (70−51 )−0.0003(77.98176)
¿1.947 kW