anup
17-03-2006, 05:43 PM
Dear Technocrats,
I am designing air source heat pump for water heating for Indian conditions
As a first step, the evaporator is designed. While designing, I have considered two ambient conditions, delta T across evaporator is 46.4 deg. F (8 deg.C.) and R.H. 25%
The inputs and output calculations are attached.
Kindly guide me to design it perfectly.
How much delta T should be designed for getting optimum COP?
If you face any problem whie reading below calculations, I have attached the same as an attachment.
Evaporator Design
Sr. No. Parameters Units Case 1 Case 2
a Input
1 Inlet Air Temp deg. F 89.6 68
2 Outlet Air temp deg. F 75.2 53.6
3 R.H. at inlet air temp considered 25% 25%
4 R.H. g/m3 33.83 17.3
kg/m3 0.03383 0.0173
5 Refrigerant type R 22 R22
6 Heat Load Kw 20.15 20.15
7 Air Flow CFM 3431 3711
m3/hr 5830 6305
8 LMTD deg. F 68.97 46.67
9 Tube Material Cu Cu
b Output
1 No. of tubes nos 120 180
2 Tube length mtr 1.2 1.2
3 Tube OD mm 12.7 12.7
4 Tube ID nos 8.5 8.5
5 No.of Fins/inch nos 13 13
6 No. of rows nos 3 3
7 No. of passes nos 14 14
I am designing air source heat pump for water heating for Indian conditions
As a first step, the evaporator is designed. While designing, I have considered two ambient conditions, delta T across evaporator is 46.4 deg. F (8 deg.C.) and R.H. 25%
The inputs and output calculations are attached.
Kindly guide me to design it perfectly.
How much delta T should be designed for getting optimum COP?
If you face any problem whie reading below calculations, I have attached the same as an attachment.
Evaporator Design
Sr. No. Parameters Units Case 1 Case 2
a Input
1 Inlet Air Temp deg. F 89.6 68
2 Outlet Air temp deg. F 75.2 53.6
3 R.H. at inlet air temp considered 25% 25%
4 R.H. g/m3 33.83 17.3
kg/m3 0.03383 0.0173
5 Refrigerant type R 22 R22
6 Heat Load Kw 20.15 20.15
7 Air Flow CFM 3431 3711
m3/hr 5830 6305
8 LMTD deg. F 68.97 46.67
9 Tube Material Cu Cu
b Output
1 No. of tubes nos 120 180
2 Tube length mtr 1.2 1.2
3 Tube OD mm 12.7 12.7
4 Tube ID nos 8.5 8.5
5 No.of Fins/inch nos 13 13
6 No. of rows nos 3 3
7 No. of passes nos 14 14