14
Performance Data
Performance Data
Calculation Steps
Interpolation
method can be used to get the total
cooling capacity,
TC
and sensible cooling capacity,
SC
and power input,
PI
at those temperatures which
are not stated out in the table. Extrapolation method
is not allowed to be used.
Example:
Indoor Condition:
25°C DB, 17°C WB
Outdoor Condition:
37°C DB
Fan Speed:
High
Solution:
Based on the Performance Table,
1. Refer to the Indoor DB column,
-
25°C
is located between 24°C & 27°C
for 16°C WB.
-
25°C
is located between 24°C & 27°C
for 19°C WB.
-Thus, Interpolation needs to be applied.
2. Refer to the Indoor WB column,
-
17°C
is located between 16°C & 19°C
for 25°C DB.
-Thus, Interpolation needs to be applied.
3. Refer to the Outdoor DB column,
-
37°C
is located between 35°C & 40°C.
-Thus, Interpolation needs to be applied.
1
st
Step
Interpolation of Indoor WB
Find TC, SC & PI
(a) Indoor:
25°C DB
, 16°C WB
Outdoor: 35°C DB
(b) Indoor:
25°C DB
, 19°C WB
Outdoor: 35°C DB
(c) Indoor:
25°C DB
, 16°C WB
Outdoor: 40°C DB
(d) Indoor:
25°C DB
, 19°C WB
Outdoor: 40°C DB
2
nd
Step
Interpolation of Indoor DB
Find TC, SC & PI
(a) Indoor: 25°C DB,
17°C WB
Outdoor: 35°C DB
(b) Indoor: 25°C DB,
17°C WB
Outdoor: 40°C DB
3
rd
Step
Interpolation of Outdoor DB
Find TC, SC & PI
(a) Indoor: 25°C DB, 17°C WB
Outdoor:
37°C DB
Details of Calculation:
1
st
Step:
To obtain the TC, SC & PI for
(a) Indoor Condition:
25°C DB, 16°C WB
Outdoor Condition:
35°C DB
EWB
EDB
Outdoor temperature
35°C
TC
SC
PI
16
24
2.33
2.32
0.68
25
x
1
y
1
z
1
27
2.40
2.40
0.68
By Interpolation Method
⇒
25°C – 24°C
=
x
1
– 2.33 kW
27°C – 24°C
2.40 kW – 2.33 kW
⇒
x
1
= 2.35 kW
Similarly
,
y
1
= 2.35 kW
z
1
= 0.68 kW
